app.py

import streamlit as st
import tensorflow as tf
from tensorflow.keras.models import Model
from tensorflow.keras.layers import *
from tensorflow.keras.optimizers import Adam
import cv2
import os
import numpy as np
import matplotlib.pyplot as plt
from PIL import Image
import io
import base64
import tempfile
import zipfile
import random
import time
import rasterio
from rasterio.errors import RasterioIOError
import h5py
import json

# Set page configuration
st.set_page_config(
    page_title="SAR Image Colorization",
    page_icon="🛰",
    layout="wide"
)


def display_image(image_path):
    """Display an image with proper handling for different formats"""
    try:
        if os.path.exists(image_path):
            if image_path.lower().endswith(('.tif', '.tiff')):
                # Use rasterio for TIF files
                try:
                    with rasterio.open(image_path) as src:
                        img_data = src.read(1)  # Read first band for single-band images
                        
                        # For multi-band images
                        if src.count > 1:
                            # For RGB images
                            if src.count >= 3:
                                img_data = np.dstack([src.read(i) for i in range(1, 4)])
                            else:
                                # For 2-band images, duplicate the second band
                                img_data = np.dstack([src.read(1), src.read(2), src.read(2)])
                        else:
                            # For single-band images, create an RGB image
                            img_data = np.dstack([img_data, img_data, img_data])
                        
                        # Normalize for display
                        if img_data.dtype != np.uint8:
                            img_data = (img_data - np.min(img_data)) / (np.max(img_data) - np.min(img_data)) * 255
                            img_data = img_data.astype(np.uint8)
                        
                        st.image(img_data, use_container_width=True)
                except Exception as rasterio_error:
                    # Fall back to PIL
                    try:
                        img = Image.open(image_path)
                        st.image(img, use_container_width=True)
                    except Exception as pil_error:
                        st.error(f"Failed to load image: {str(pil_error)}")
            else:
                # Use PIL for other formats
                img = Image.open(image_path)
                st.image(img, use_container_width=True)
        else:
            st.info(f"Image file not found: {image_path}")
    except Exception as e:
        st.error(f"Error loading image: {str(e)}")

# ==================== UTILITY FUNCTIONS ====================

# GPU setup for SAR to Optical Translation
@st.cache_resource
def setup_gpu():
    gpus = tf.config.experimental.list_physical_devices('GPU')
    if gpus:
        for gpu in gpus:
            tf.config.experimental.set_memory_growth(gpu, True)
        return f"GPU setup complete. Found {len(gpus)} GPU(s)."
    return "No GPUs found. Running on CPU."

# ESA WorldCover colors dictionary - used in multiple functions
def get_esa_colors():
    return {
        0: [0, 100, 0],     # Trees - Dark green
        1: [255, 165, 0],   # Shrubland - Orange
        2: [144, 238, 144], # Grassland - Light green
        3: [255, 255, 0],   # Cropland - Yellow
        4: [255, 0, 0],     # Built-up - Red
        5: [139, 69, 19],   # Bare - Brown
        6: [255, 255, 255], # Snow - White
        7: [0, 0, 255],     # Water - Blue
        8: [0, 139, 139],   # Wetland - Dark cyan
        9: [0, 255, 0],     # Mangroves - Bright green
        10: [220, 220, 220] # Moss - Light grey
    }

# When visualizing ground truth, use the same color mapping as for predictions
def visualize_with_ground_truth(sar_image, ground_truth, prediction):
    """Visualize SAR image with ground truth and prediction using ESA WorldCover colors"""
    # ESA WorldCover colors
    colors = get_esa_colors()
    
    # Convert prediction to color image
    pred_class = np.argmax(prediction[0], axis=-1)
    colored_pred = np.zeros((pred_class.shape[0], pred_class.shape[1], 3), dtype=np.uint8)
    
    for class_idx, color in colors.items():
        colored_pred[pred_class == class_idx] = color
    
    # Convert ground truth to color image using the same color scheme
    gt_class = ground_truth[:,:,0].astype(np.int32)
    
    # Normalize ground truth to match prediction classes if needed
    if np.max(gt_class) > 10:  # If using ESA WorldCover values
        # Map ESA values to 0-10 indices
        gt_mapped = np.zeros_like(gt_class)
        class_values = sorted(st.session_state.segmentation.class_definitions.values())
        for i, val in enumerate(class_values):
            gt_mapped[gt_class == val] = i
        gt_class = gt_mapped
    
    colored_gt = np.zeros((gt_class.shape[0], gt_class.shape[1], 3), dtype=np.uint8)
    
    for class_idx, color in colors.items():
        colored_gt[gt_class == class_idx] = color
    
    # Create overlay for SAR with prediction
    sar_rgb = np.repeat(sar_image[:, :, 0:1], 3, axis=2)
    # Normalize to 0-255 for visualization
    sar_rgb = ((sar_rgb + 1) / 2 * 255).astype(np.uint8)
    
    overlay = cv2.addWeighted(
        sar_rgb,
        0.7,
        colored_pred,
        0.3,
        0
    )
    
    # Set background color based on theme
    bg_color = '#0a0a1f' if st.session_state.theme == 'dark' else '#ffffff'
    text_color = 'white' if st.session_state.theme == 'dark' else 'black'
    
    # Create figure
    fig, axes = plt.subplots(1, 4, figsize=(16, 4))
    
    # Original SAR
    axes[0].imshow(sar_rgb, cmap='gray')
    axes[0].set_title('Original SAR', color=text_color)
    axes[0].axis('off')
    
    # Ground Truth
    axes[1].imshow(colored_gt)
    axes[1].set_title('Ground Truth', color=text_color)
    axes[1].axis('off')
    
    # Prediction
    axes[2].imshow(colored_pred)
    axes[2].set_title('Prediction', color=text_color)
    axes[2].axis('off')
    
    # Overlay
    axes[3].imshow(overlay)
    axes[3].set_title('Colorized Output', color=text_color)
    axes[3].axis('off')
    
    # Set background color
    fig.patch.set_facecolor(bg_color)
    for ax in axes:
        ax.set_facecolor(bg_color)
    
    plt.tight_layout()
    
    # Convert plot to image
    buf = io.BytesIO()
    plt.savefig(buf, format='png', facecolor=bg_color, bbox_inches='tight')
    buf.seek(0)
    plt.close(fig)
    
    return buf, colored_gt, colored_pred, overlay


# Load models for SAR to Optical Translation
@st.cache_resource
def load_models(unet_weights_path, generator_path=None):
    # Load U-Net model
    unet = get_unet(input_shape=(256, 256, 1), classes=11)
    unet.load_weights(unet_weights_path)
    
    # Load generator model if path is provided
    generator = None
    if generator_path:
        try:
            generator = tf.keras.models.load_model(generator_path)
        except Exception as e:
            st.error(f"Error loading generator model: {e}")
    
    return unet, generator

# Preprocess SAR data for SAR to Optical Translation
def preprocess_sar_for_optical(sar_data):
    """Preprocess SAR data"""
    # Data is assumed to be in dB scale
    sar_clipped = np.clip(sar_data, -50, 20)
    sar_normalized = (sar_clipped - np.min(sar_clipped)) / (np.max(sar_clipped) - np.min(sar_clipped)) * 2 - 1
    return sar_normalized

# Load SAR image for SAR to Optical Translation
def load_sar_image(file, img_size=(256, 256)):
    # Create a temporary file to save the uploaded file
    with tempfile.NamedTemporaryFile(delete=False, suffix='.tif') as tmp_file:
        tmp_file.write(file.getbuffer())
        tmp_file_path = tmp_file.name
    
    try:
        with rasterio.open(tmp_file_path) as src:
            image = src.read(1)
            image = cv2.resize(image, img_size)
            image = np.expand_dims(image, axis=-1)
            
            # Preprocess the image
            image = preprocess_sar_for_optical(image)
            return np.expand_dims(image, axis=0), image
    except Exception as e:
        st.error(f"Error loading SAR image: {e}")
        return None, None
    finally:
        # Clean up the temporary file
        os.unlink(tmp_file_path)

# Process image with models for SAR to Optical Translation
def process_image(sar_image, unet_model, generator_model=None):
    # Get segmentation using U-Net
    seg_mask = unet_model.predict(sar_image)
    
    # Generate optical using segmentation if generator is available
    colorized = None
    if generator_model:
        colorized = generator_model.predict([sar_image, seg_mask])
        colorized = colorized[0]

    return seg_mask[0], colorized

# Visualize results for SAR to Optical Translation
def visualize_results(sar_image, seg_mask, colorized=None):
    # ESA WorldCover colors
    colors = get_esa_colors()
    
    # Convert prediction to color image
    pred_class = np.argmax(seg_mask, axis=-1)
    colored_pred = np.zeros((pred_class.shape[0], pred_class.shape[1], 3), dtype=np.uint8)
    
    for class_idx, color in colors.items():
        colored_pred[pred_class == class_idx] = color
    
    # Create overlay
    sar_rgb = np.repeat(sar_image[:, :, 0:1], 3, axis=2)
    # Normalize to 0-255 for visualization
    sar_rgb = ((sar_rgb + 1) / 2 * 255).astype(np.uint8)
    
    overlay = cv2.addWeighted(
        sar_rgb,
        0.7,
        colored_pred,
        0.3,
        0
    )
    
    return sar_rgb, colored_pred, overlay, colorized


# Load model with weights - handles different model loading scenarios
def load_model_with_weights(model_path):
    """Load a model directly from an H5 file, preserving the original architecture"""
    # If model_path is a filename without path, prepend the models directory
    if not os.path.dirname(model_path) and not model_path.startswith('models/'):
        model_path = os.path.join('models', os.path.basename(model_path))
        
    try:
        # Try to load the complete model (architecture + weights)
        # For Keras 3 compatibility
        import tensorflow as tf
        keras_version = tf.keras.__version__[0]
        
        if keras_version == '3':
            # For Keras 3, try to load with custom_objects to handle compatibility issues
            custom_objects = {
                'BilinearUpsampling': BilinearUpsampling  # Make sure this class is defined
            }
            model = tf.keras.models.load_model(model_path, compile=False, custom_objects=custom_objects)
        else:
            # For older Keras versions
            model = tf.keras.models.load_model(model_path, compile=False)
            
        print("Loaded complete model with architecture")
        return model
    except Exception as e:
        print(f"Could not load complete model: {str(e)}")
        print("Attempting to load just the weights into a matching architecture...")
               
        # Try to inspect the model file to determine architecture
        try:
            with h5py.File(model_path, 'r') as f:
                model_config = None
                if 'model_config' in f.attrs:
                    model_config = json.loads(f.attrs['model_config'].decode('utf-8'))
                           
                # If we found a model config, try to recreate it
                if model_config:
                    try:
                        model = tf.keras.models.model_from_json(json.dumps(model_config))
                        model.load_weights(model_path)
                        print("Successfully loaded model from config and weights")
                        return model
                    except Exception as e2:
                        print(f"Failed to load from config: {str(e2)}")
        except Exception as e3:
            print(f"Failed to inspect model file: {str(e3)}")
            
        # If all else fails, create a new model and try to load weights
        try:
            # Create a new model based on the model_type in session state
            if st.session_state.segmentation.model_type == 'unet':
                model = get_unet(
                    input_shape=(256, 256, 1),
                    drop_rate=0.3,
                    classes=11
                )
            elif st.session_state.segmentation.model_type == 'deeplabv3plus':
                model = DeepLabV3Plus(
                    input_shape=(256, 256, 1),
                    classes=11
                )
            elif st.session_state.segmentation.model_type == 'segnet':
                model = SegNet(
                    input_shape=(256, 256, 1),
                    classes=11
                )
            
            # Try to load weights with skip_mismatch
            model.load_weights(model_path, by_name=True, skip_mismatch=True)
            print("Created new model and loaded compatible weights")
            return model
        except Exception as e4:
            print(f"Failed to create new model and load weights: {str(e4)}")
               
        # If all else fails, return None
        return None

# Create a legend for the land cover classes
def create_legend():
    """Create a legend for the land cover classes"""
    colors = {
        'Trees': [0, 100, 0],
        'Shrubland': [255, 165, 0],
        'Grassland': [144, 238, 144],
        'Cropland': [255, 255, 0],
        'Built-up': [255, 0, 0],
        'Bare': [139, 69, 19],
        'Snow': [255, 255, 255],
        'Water': [0, 0, 255],
        'Wetland': [0, 139, 139],
        'Mangroves': [0, 255, 0],
        'Moss': [220, 220, 220]
    }
    
    # Set background color based on theme
    bg_color = '#0a0a1f' if st.session_state.theme == 'dark' else '#ffffff'
    text_color = 'white' if st.session_state.theme == 'dark' else 'black'
    
    fig, ax = plt.subplots(figsize=(8, 4))
    fig.patch.set_facecolor(bg_color)
    ax.set_facecolor(bg_color)
    
    # Create color patches
    for i, (class_name, color) in enumerate(colors.items()):
        ax.add_patch(plt.Rectangle((0, i), 0.5, 0.8, color=[c/255 for c in color]))
        ax.text(0.7, i + 0.4, class_name, color=text_color, fontsize=12)
    
    ax.set_xlim(0, 3)
    ax.set_ylim(-0.5, len(colors) - 0.5)
    ax.set_title('Land Cover Classes', color=text_color, fontsize=14)
    ax.axis('off')
    
    buf = io.BytesIO()
    plt.savefig(buf, format='png', facecolor=bg_color, bbox_inches='tight')
    buf.seek(0)
    plt.close(fig)
    
    return buf


# Visualize segmentation prediction
# Update the visualize_prediction function to support both themes
def visualize_prediction(prediction, original_sar, figsize=(10, 4)):
    """Visualize segmentation prediction with ESA WorldCover colors"""
    # ESA WorldCover colors
    colors = get_esa_colors()
    
    # Convert prediction to color image
    pred_class = np.argmax(prediction[0], axis=-1)
    colored_pred = np.zeros((pred_class.shape[0], pred_class.shape[1], 3), dtype=np.uint8)
    
    for class_idx, color in colors.items():
        colored_pred[pred_class == class_idx] = color
    
    # Create overlay
    sar_rgb = cv2.cvtColor(original_sar[:,:,0], cv2.COLOR_GRAY2RGB)
    overlay = cv2.addWeighted(sar_rgb, 0.7, colored_pred, 0.3, 0)
    
    # Create figure
    fig, axes = plt.subplots(1, 3, figsize=figsize)
    
    # Set background color based on theme
    bg_color = '#0a0a1f' if st.session_state.theme == 'dark' else '#ffffff'
    text_color = 'white' if st.session_state.theme == 'dark' else 'black'
    
    # Original SAR
    axes[0].imshow(original_sar[:,:,0], cmap='gray')
    axes[0].set_title('Original SAR', color=text_color)
    axes[0].axis('off')
    
    # Prediction
    axes[1].imshow(colored_pred)
    axes[1].set_title('Prediction', color=text_color)
    axes[1].axis('off')
    
    # Overlay
    axes[2].imshow(overlay)
    axes[2].set_title('Colorized Output', color=text_color)
    axes[2].axis('off')
    
    # Set background color
    fig.patch.set_facecolor(bg_color)
    for ax in axes:
        ax.set_facecolor(bg_color)
    
    plt.tight_layout()
    
    # Convert plot to image
    buf = io.BytesIO()
    plt.savefig(buf, format='png', facecolor=bg_color, bbox_inches='tight')
    buf.seek(0)
    plt.close(fig)
    return buf

# ==================== MODEL DEFINITIONS ====================

# Define the U-Net model
def get_unet(input_shape=(256, 256, 1), drop_rate=0.3, classes=11):
    inputs = Input(input_shape)
    
    # Encoder
    conv1_1 = Conv2D(64, 3, activation='relu', padding='same', kernel_initializer='he_normal')(inputs)
    batch1_1 = BatchNormalization()(conv1_1)
    conv1_2 = Conv2D(64, 3, activation='relu', padding='same', kernel_initializer='he_normal')(batch1_1)
    batch1_2 = BatchNormalization()(conv1_2)
    pool1 = MaxPooling2D(pool_size=(2, 2))(batch1_2)

    conv2_1 = Conv2D(128, 3, activation='relu', padding='same', kernel_initializer='he_normal')(pool1)
    batch2_1 = BatchNormalization()(conv2_1)
    conv2_2 = Conv2D(128, 3, activation='relu', padding='same', kernel_initializer='he_normal')(batch2_1)
    batch2_2 = BatchNormalization()(conv2_2)
    pool2 = MaxPooling2D(pool_size=(2, 2))(batch2_2)

    conv3_1 = Conv2D(256, 3, activation='relu', padding='same', kernel_initializer='he_normal')(pool2)
    batch3_1 = BatchNormalization()(conv3_1)
    conv3_2 = Conv2D(256, 3, activation='relu', padding='same', kernel_initializer='he_normal')(batch3_1)
    batch3_2 = BatchNormalization()(conv3_2)
    pool3 = MaxPooling2D(pool_size=(2, 2))(batch3_2)

    conv4_1 = Conv2D(512, 3, activation='relu', padding='same', kernel_initializer='he_normal')(pool3)
    batch4_1 = BatchNormalization()(conv4_1)
    conv4_2 = Conv2D(512, 3, activation='relu', padding='same', kernel_initializer='he_normal')(batch4_1)
    batch4_2 = BatchNormalization()(conv4_2)
    drop4 = Dropout(drop_rate)(batch4_2)
    pool4 = MaxPooling2D(pool_size=(2, 2))(drop4)

    # Bridge
    conv5_1 = Conv2D(1024, 3, activation='relu', padding='same', kernel_initializer='he_normal')(pool4)
    batch5_1 = BatchNormalization()(conv5_1)
    conv5_2 = Conv2D(1024, 3, activation='relu', padding='same', kernel_initializer='he_normal')(batch5_1)
    batch5_2 = BatchNormalization()(conv5_2)
    drop5 = Dropout(drop_rate)(batch5_2)

    # Decoder
    up6 = Conv2D(512, 2, activation='relu', padding='same')(UpSampling2D(size=(2, 2))(drop5))
    merge6 = concatenate([drop4, up6])
    conv6_1 = Conv2D(512, 3, activation='relu', padding='same', kernel_initializer='he_normal')(merge6)
    batch6_1 = BatchNormalization()(conv6_1)
    conv6_2 = Conv2D(512, 3, activation='relu', padding='same', kernel_initializer='he_normal')(batch6_1)
    batch6_2 = BatchNormalization()(conv6_2)

    up7 = Conv2D(256, 2, activation='relu', padding='same')(UpSampling2D(size=(2, 2))(batch6_2))
    merge7 = concatenate([batch3_2, up7])
    conv7_1 = Conv2D(256, 3, activation='relu', padding='same', kernel_initializer='he_normal')(merge7)
    batch7_1 = BatchNormalization()(conv7_1)
    conv7_2 = Conv2D(256, 3, activation='relu', padding='same', kernel_initializer='he_normal')(batch7_1)
    batch7_2 = BatchNormalization()(conv7_2)

    up8 = Conv2D(128, 2, activation='relu', padding='same')(UpSampling2D(size=(2, 2))(batch7_2))
    merge8 = concatenate([batch2_2, up8])
    conv8_1 = Conv2D(128, 3, activation='relu', padding='same', kernel_initializer='he_normal')(merge8)
    batch8_1 = BatchNormalization()(conv8_1)
    conv8_2 = Conv2D(128, 3, activation='relu', padding='same', kernel_initializer='he_normal')(batch8_1)
    batch8_2 = BatchNormalization()(conv8_2)

    up9 = Conv2D(64, 2, activation='relu', padding='same')(UpSampling2D(size=(2, 2))(batch8_2))
    merge9 = concatenate([batch1_2, up9])
    conv9_1 = Conv2D(64, 3, activation='relu', padding='same', kernel_initializer='he_normal')(merge9)
    batch9_1 = BatchNormalization()(conv9_1)
    conv9_2 = Conv2D(64, 3, activation='relu', padding='same', kernel_initializer='he_normal')(batch9_1)
    batch9_2 = BatchNormalization()(conv9_2)

    outputs = Conv2D(classes, 1, activation='softmax')(batch9_2)

    model = Model(inputs=inputs, outputs=outputs)
    model.compile(optimizer=Adam(learning_rate=1e-4),
                 loss='categorical_crossentropy',
                 metrics=['accuracy'])
    
    return model

# Custom upsampling layer for dynamic resizing
class BilinearUpsampling(Layer):
    def __init__(self, size=(1, 1), **kwargs):
        super(BilinearUpsampling, self).__init__(**kwargs)
        self.size = size

    def call(self, inputs):
        return tf.image.resize(inputs, self.size, method='bilinear')
   
    def compute_output_shape(self, input_shape):
        return (input_shape[0], self.size[0], self.size[1], input_shape[3])
       
    def get_config(self):
        config = super(BilinearUpsampling, self).get_config()
        config.update({'size': self.size})
        return config

# DeepLabV3+ model definition
def DeepLabV3Plus(input_shape=(256, 256, 1), classes=11, output_stride=16):
    """
    DeepLabV3+ model with Xception backbone
   
    Args:
        input_shape: Shape of input images
        classes: Number of classes for segmentation
        output_stride: Output stride for dilated convolutions (16 or 8)
       
    Returns:
        model: DeepLabV3+ model
    """
    # Input layer
    inputs = Input(input_shape)
   
    # Ensure we're using the right dilation rates based on output_stride
    if output_stride == 16:
        atrous_rates = (6, 12, 18)
    elif output_stride == 8:
        atrous_rates = (12, 24, 36)
    else:
        raise ValueError("Output stride must be 8 or 16")
   
    # === ENCODER (BACKBONE) ===
    # Entry block
    x = Conv2D(32, 3, strides=(2, 2), padding='same', use_bias=False)(inputs)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
   
    x = Conv2D(64, 3, padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
   
    # Xception-like blocks with dilated convolutions
    # Block 1
    residual = Conv2D(128, 1, strides=(2, 2), padding='same', use_bias=False)(x)
    residual = BatchNormalization()(residual)
   
    x = SeparableConv2D(128, 3, padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = SeparableConv2D(128, 3, padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = MaxPooling2D(3, strides=(2, 2), padding='same')(x)
    x = Add()([x, residual])
   
    # Block 2
    residual = Conv2D(256, 1, strides=(2, 2), padding='same', use_bias=False)(x)
    residual = BatchNormalization()(residual)
   
    x = Activation('relu')(x)
    x = SeparableConv2D(256, 3, padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = SeparableConv2D(256, 3, padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = MaxPooling2D(3, strides=(2, 2), padding='same')(x)
    x = Add()([x, residual])
   
    # Save low_level_features for skip connection (1/4 of input size)
    low_level_features = x  
   
    # Block 3
    residual = Conv2D(728, 1, strides=(2, 2), padding='same', use_bias=False)(x)
    residual = BatchNormalization()(residual)
   
    x = Activation('relu')(x)
    x = SeparableConv2D(728, 3, padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = SeparableConv2D(728, 3, padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = MaxPooling2D(3, strides=(2, 2), padding='same')(x)
    x = Add()([x, residual])
   
    # Middle flow - modified with dilated convolutions
    for i in range(16):
        residual = x
       
        x = Activation('relu')(x)
        x = SeparableConv2D(728, 3, padding='same', dilation_rate=2, use_bias=False)(x)
        x = BatchNormalization()(x)
        x = Activation('relu')(x)
        x = SeparableConv2D(728, 3, padding='same', dilation_rate=2, use_bias=False)(x)
        x = BatchNormalization()(x)
        x = Activation('relu')(x)
        x = SeparableConv2D(728, 3, padding='same', dilation_rate=2, use_bias=False)(x)
        x = BatchNormalization()(x)
       
        x = Add()([x, residual])
   
    # Exit flow (modified)
    x = Activation('relu')(x)
    x = SeparableConv2D(728, 3, padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = SeparableConv2D(1024, 3, padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
   
    # === ASPP (Atrous Spatial Pyramid Pooling) ===
    # 1x1 convolution branch
    aspp_out1 = Conv2D(256, 1, padding='same', use_bias=False)(x)
    aspp_out1 = BatchNormalization()(aspp_out1)
    aspp_out1 = Activation('relu')(aspp_out1)
   
    # 3x3 dilated convolution branches with different rates
    aspp_out2 = Conv2D(256, 3, padding='same', dilation_rate=atrous_rates[0], use_bias=False)(x)
    aspp_out2 = BatchNormalization()(aspp_out2)
    aspp_out2 = Activation('relu')(aspp_out2)
   
    aspp_out3 = Conv2D(256, 3, padding='same', dilation_rate=atrous_rates[1], use_bias=False)(x)
    aspp_out3 = BatchNormalization()(aspp_out3)
    aspp_out3 = Activation('relu')(aspp_out3)
   
    aspp_out4 = Conv2D(256, 3, padding='same', dilation_rate=atrous_rates[2], use_bias=False)(x)
    aspp_out4 = BatchNormalization()(aspp_out4)
    aspp_out4 = Activation('relu')(aspp_out4)
   
    # Global pooling branch
    # Global pooling branch
    aspp_out5 = GlobalAveragePooling2D()(x)
    aspp_out5 = Reshape((1, 1, 1024))(aspp_out5)  # Use 1024 to match x's channels
    aspp_out5 = Conv2D(256, 1, padding='same', use_bias=False)(aspp_out5)
    aspp_out5 = BatchNormalization()(aspp_out5)
    aspp_out5 = Activation('relu')(aspp_out5)
   
    # Get current shape of x
    _, height, width, _ = tf.keras.backend.int_shape(x)
    aspp_out5 = UpSampling2D(size=(height, width), interpolation='bilinear')(aspp_out5)
   
    # Concatenate all ASPP branches
    aspp_out = Concatenate()([aspp_out1, aspp_out2, aspp_out3, aspp_out4, aspp_out5])
   
    # Project ASPP output to 256 filters
    aspp_out = Conv2D(256, 1, padding='same', use_bias=False)(aspp_out)
    aspp_out = BatchNormalization()(aspp_out)
    aspp_out = Activation('relu')(aspp_out)
   
    # === DECODER ===
    # Process low-level features from Block 2 (1/4 size)
    low_level_features = Conv2D(48, 1, padding='same', use_bias=False)(low_level_features)
    low_level_features = BatchNormalization()(low_level_features)
    low_level_features = Activation('relu')(low_level_features)
   
    # Upsample ASPP output by 4x to match low level features size
    # Get shapes for verification
    low_level_shape = tf.keras.backend.int_shape(low_level_features)
   
    # Upsample to match low_level_features shape
    x = UpSampling2D(size=(low_level_shape[1] // tf.keras.backend.int_shape(aspp_out)[1],
                          low_level_shape[2] // tf.keras.backend.int_shape(aspp_out)[2]),
                   interpolation='bilinear')(aspp_out)
   
    # Concatenate with low-level features
    x = Concatenate()([x, low_level_features])
   
    # Final convolutions
    x = Conv2D(256, 3, padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
   
    x = Conv2D(256, 3, padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
   
    # Calculate upsampling size to original input size
    x_shape = tf.keras.backend.int_shape(x)
    upsampling_size = (input_shape[0] // x_shape[1], input_shape[1] // x_shape[2])
   
    # Upsample to original size
    x = UpSampling2D(size=upsampling_size, interpolation='bilinear')(x)
   
    # Final segmentation output
    outputs = Conv2D(classes, 1, padding='same', activation='softmax')(x)
   
    model = Model(inputs=inputs, outputs=outputs)
    model.compile(optimizer=Adam(learning_rate=1e-4),
                 loss='categorical_crossentropy',
                 metrics=['accuracy'])
   
    return model

# SegNet model definition
def SegNet(input_shape=(256, 256, 1), classes=11):
    """
    SegNet model for semantic segmentation
    
    Args:
        input_shape: Shape of input images
        classes: Number of classes for segmentation
        
    Returns:
        model: SegNet model
    """
    # Input layer
    inputs = Input(input_shape)
    
    # === ENCODER ===
    # Encoder block 1
    x = Conv2D(64, (3, 3), padding='same', use_bias=False)(inputs)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(64, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    # Regular MaxPooling without indices
    x = MaxPooling2D(pool_size=(2, 2), strides=(2, 2), padding='same')(x)
    
    # Encoder block 2
    x = Conv2D(128, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(128, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = MaxPooling2D(pool_size=(2, 2), strides=(2, 2), padding='same')(x)
    
    # Encoder block 3
    x = Conv2D(256, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(256, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(256, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = MaxPooling2D(pool_size=(2, 2), strides=(2, 2), padding='same')(x)
    
    # Encoder block 4
    x = Conv2D(512, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(512, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(512, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = MaxPooling2D(pool_size=(2, 2), strides=(2, 2), padding='same')(x)
    
    # Encoder block 5
    x = Conv2D(512, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(512, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(512, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = MaxPooling2D(pool_size=(2, 2), strides=(2, 2), padding='same')(x)
    
    # === DECODER ===
    # Using UpSampling2D instead of MaxUnpooling since TensorFlow doesn't support it
    
    # Decoder block 5
    x = UpSampling2D(size=(2, 2))(x)
    x = Conv2D(512, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(512, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(512, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    
    # Decoder block 4
    x = UpSampling2D(size=(2, 2))(x)
    x = Conv2D(512, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(512, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(256, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    
    # Decoder block 3
    x = UpSampling2D(size=(2, 2))(x)
    x = Conv2D(256, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(256, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(128, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    
    # Decoder block 2
    x = UpSampling2D(size=(2, 2))(x)
    x = Conv2D(128, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(64, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    
    # Decoder block 1
    x = UpSampling2D(size=(2, 2))(x)
    x = Conv2D(64, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    x = Conv2D(64, (3, 3), padding='same', use_bias=False)(x)
    x = BatchNormalization()(x)
    x = Activation('relu')(x)
    
    # Output layer
    outputs = Conv2D(classes, (1, 1), padding='same', activation='softmax')(x)
    
    model = Model(inputs=inputs, outputs=outputs)
    
    return model

# ==================== SAR SEGMENTATION CLASS ====================

class SARSegmentation:
    def __init__(self, img_rows=256, img_cols=256, drop_rate=0.5, model_type='unet'):
        self.img_rows = img_rows
        self.img_cols = img_cols
        self.drop_rate = drop_rate
        self.num_channels = 1  # Single-pol SAR
        self.model = None
        self.model_type = model_type.lower()
       
        # ESA WorldCover class definitions
        self.class_definitions = {
            'trees': 10,
            'shrubland': 20,
            'grassland': 30,
            'cropland': 40,
            'built_up': 50,
            'bare': 60,
            'snow': 70,
            'water': 80,
            'wetland': 90,
            'mangroves': 95,
            'moss': 100
        }
        self.num_classes = len(self.class_definitions)
       
        # Class colors for visualization
        self.class_colors = get_esa_colors()

    def load_sar_data(self, file_path_or_bytes, is_bytes=False):
        """Load SAR data from file path or bytes"""
        try:
            if is_bytes:
                # Create a temporary file to use with rasterio
                with tempfile.NamedTemporaryFile(suffix='.tif', delete=False) as tmp:
                    tmp.write(file_path_or_bytes)
                    tmp_path = tmp.name
            
                try:
                    with rasterio.open(tmp_path) as src:
                        sar_data = src.read(1)  # Read single band
                        sar_data = np.expand_dims(sar_data, axis=-1)
                except Exception as e:
                    # If rasterio fails, try PIL
                    img = Image.open(tmp_path).convert('L')
                    sar_data = np.array(img)
                    sar_data = np.expand_dims(sar_data, axis=-1)
                    
                # Clean up the temporary file
                os.unlink(tmp_path)
            else:
                try:
                    with rasterio.open(file_path_or_bytes) as src:
                        sar_data = src.read(1)  # Read single band
                        sar_data = np.expand_dims(sar_data, axis=-1)
                except RasterioIOError:
                    # Try to open as a regular image if rasterio fails
                    img = Image.open(file_path_or_bytes).convert('L')
                    sar_data = np.array(img)
                    sar_data = np.expand_dims(sar_data, axis=-1)
        
            # Resize if needed
            if sar_data.shape[:2] != (self.img_rows, self.img_cols):
                sar_data = cv2.resize(sar_data, (self.img_cols, self.img_rows))
                sar_data = np.expand_dims(sar_data, axis=-1)
        
            return sar_data
        except Exception as e:
            raise ValueError(f"Failed to load SAR data: {str(e)}")

    def preprocess_sar(self, sar_data):
        """Preprocess SAR data"""
        # Check if data is already normalized (0-255 range)
        if np.max(sar_data) <= 255 and np.min(sar_data) >= 0:
            # Normalize to -1 to 1 range
            sar_normalized = (sar_data / 127.5) - 1
        else:
            # Assume it's in dB scale
            sar_clipped = np.clip(sar_data, -50, 20)
            sar_normalized = (sar_clipped - np.min(sar_clipped)) / (np.max(sar_clipped) - np.min(sar_clipped)) * 2 - 1
        
        return sar_normalized

    def one_hot_encode(self, labels):
        """Convert ESA WorldCover labels to one-hot encoded format"""
        encoded = np.zeros((labels.shape[0], labels.shape[1], self.num_classes))
        
        for i, value in enumerate(sorted(self.class_definitions.values())):
            encoded[:, :, i] = (labels == value)
        
        return encoded

    def load_trained_model(self, model_path):
        """Load a trained model from file"""
        try:
            # If model_path is a filename without path, prepend the models directory
            if not os.path.dirname(model_path) and not model_path.startswith('models/'):
                model_path = os.path.join('models', os.path.basename(model_path))
                
            # First try to load the complete model
            self.model = load_model_with_weights(model_path)
                    
            if self.model is not None:
                has_dilated_convs = False
                for layer in self.model.layers:
                    if 'conv' in layer.name.lower() and hasattr(layer, 'dilation_rate'):
                        if isinstance(layer.dilation_rate, (list, tuple)):
                            if any(rate > 1 for rate in layer.dilation_rate):
                                has_dilated_convs = True
                                break
                        elif layer.dilation_rate > 1:
                            has_dilated_convs = True
                            break
                            
                if has_dilated_convs:
                    self.model_type = 'deeplabv3plus'
                    print("Detected DeepLabV3+ model")
                # Check for SegNet architecture (typically has 5 encoder and 5 decoder blocks)
                elif len([l for l in self.model.layers if isinstance(l, MaxPooling2D)]) >= 5:
                    self.model_type = 'segnet'
                    print("Detected SegNet model")
                else:
                    self.model_type = 'unet'
                    print("Detected U-Net model")
                    
            if self.model is None:
                # If that fails, try to create a model with the expected architecture
                if self.model_type == 'unet':
                    self.model = get_unet(
                        input_shape=(self.img_rows, self.img_cols, self.num_channels),
                        drop_rate=self.drop_rate,
                        classes=self.num_classes
                    )
                elif self.model_type == 'deeplabv3plus':
                    self.model = DeepLabV3Plus(
                        input_shape=(self.img_rows, self.img_cols, self.num_channels),
                        classes=self.num_classes
                    )
                elif self.model_type == 'segnet':
                    self.model = SegNet(
                        input_shape=(self.img_rows, self.img_cols, self.num_channels),
                        classes=self.num_classes
                    )
                else:
                    raise ValueError(f"Model type {self.model_type} not supported")
                                    
                # Try to load weights, allowing for mismatch
                self.model.load_weights(model_path, by_name=True, skip_mismatch=True)
                                
                # Check if any weights were loaded
                if not any(np.any(w) for w in self.model.get_weights()):
                    raise ValueError("No weights were loaded. The model architecture is incompatible.")
        except Exception as e:
            raise ValueError(f"Failed to load model: {str(e)}")

    def predict(self, sar_data):
        """Predict segmentation for new SAR data"""
        if self.model is None:
            raise ValueError("Model not trained. Call train() first or load a trained model.")
        
        # Preprocess input data
        sar_processed = self.preprocess_sar(sar_data)
        
        # Ensure correct shape
        if len(sar_processed.shape) == 3:
            sar_processed = np.expand_dims(sar_processed, axis=0)
        
        # Make prediction
        prediction = self.model.predict(sar_processed)
        return prediction

    def get_colored_prediction(self, prediction):
        """Convert prediction to colored image"""
        pred_class = np.argmax(prediction[0], axis=-1)
        colored_pred = np.zeros((pred_class.shape[0], pred_class.shape[1], 3), dtype=np.uint8)
        
        for class_idx, color in self.class_colors.items():
            colored_pred[pred_class == class_idx] = color
        
        return colored_pred, pred_class

# ==================== UI SETUP AND STYLING ====================

# Initialize session state variables
# Initialize session state variables
if 'app_mode' not in st.session_state:
    st.session_state.app_mode = "SAR Colorization"
if 'model_loaded' not in st.session_state:
    st.session_state.model_loaded = False
if 'segmentation' not in st.session_state:
    st.session_state.segmentation = SARSegmentation(img_rows=256, img_cols=256)
if 'processed_images' not in st.session_state:
    st.session_state.processed_images = []
if 'theme' not in st.session_state:
    st.session_state.theme = "dark"  # Default theme
# Apply a single consistent style for the entire app
def set_app_style(app_mode):
    if app_mode == "SAR Colorization":
        # Dark theme styling for SAR Colorization
        st.markdown(
            """
            <style>
            .stApp {
                background-color: #0a0a1f;
                color: white;
            }
            
            .main {
                background-image: url("https://images.unsplash.com/photo-1451187580459-43490279c0fa?ixlib=rb-1.2.1&auto=format&fit=crop&w=1352&q=80");
                background-size: cover;
                background-position: center;
                background-repeat: no-repeat;
                background-attachment: fixed;
                position: relative;
            }
            
            .main::before {
                content: "";
                position: absolute;
                top: 0;
                left: 0;
                width: 100%;
                height: 100%;
                background-color: rgba(10, 10, 31, 0.7);
                backdrop-filter: blur(5px);
                z-index: -1;
            }
            
            /* Rest of your dark theme CSS */
            /* ... */
            </style>
            """,
            unsafe_allow_html=True
        )
    elif app_mode == "SAR to Optical Translation":
        # Light theme styling for SAR to Optical Translation
        st.markdown(
            """
            <style>
            .stApp {
                background-color: #f8f9fa;
                color: #333;
            }
            
            .main {
                background-image: url("https://images.unsplash.com/photo-1451187580459-43490279c0fa?ixlib=rb-1.2.1&auto=format&fit=crop&w=1352&q=80");
                background-size: cover;
                background-position: center;
                background-repeat: no-repeat;
                background-attachment: fixed;
                position: relative;
            }
            
            .main::before {
                content: "";
                position: absolute;
                top: 0;
                left: 0;
                width: 100%;
                height: 100%;
                background-color: rgba(248, 249, 250, 0.7);
                backdrop-filter: blur(5px);
                z-index: -1;
            }
            
            /* Adjust text colors for light theme */
            h1, h2, h3, h4, h5, h6 {
                color: #333 !important;
            }
            
            p, span, div, label {
                color: #333 !important;
            }
            
            /* Adjust card styling for light theme */
            .card {
                background-color: rgba(255, 255, 255, 0.7) !important;
                border: 1px solid rgba(147, 51, 234, 0.3) !important;
            }
            
            /* Adjust metric card styling for light theme */
            .metric-card {
                background-color: rgba(255, 255, 255, 0.7) !important;
            }
            
            .metric-value {
                color: #7c3aed !important;
            }
            
            .metric-label {
                color: #333 !important;
            }
            
            /* Rest of your light theme adjustments */
            /* ... */
            </style>
            """,
            unsafe_allow_html=True
        )
    
# Create twinkling stars
def create_stars_html(num_stars=100):
    stars_html = """<div class="stars">"""
    for i in range(num_stars):
        size = random.uniform(1, 3)
        top = random.uniform(0, 100)
        left = random.uniform(0, 100)
        duration = random.uniform(3, 8)
        opacity = random.uniform(0.2, 0.8)
        
        stars_html += f"""
        <div class="star" style="
            width: {size}px;
            height: {size}px;
            top: {top}%;
            left: {left}%;
            --duration: {duration}s;
            --opacity: {opacity};
        "></div>
        """
    stars_html += "</div>"
    return stars_html

# Add logo
def add_logo(logo_path='assets/logo2.png'):
    try:
        with open(logo_path, "rb") as img_file:
            logo_base64 = base64.b64encode(img_file.read()).decode()
            st.markdown(
                f"""<div style="position: absolute; top: 0.5rem; left: 1rem; z-index: 999;">
                <img src="data:image/png;base64,{logo_base64}" width="150px"></div>""", 
                unsafe_allow_html=True
            )
    except FileNotFoundError:
        st.warning(f"Logo file not found: {logo_path}")

# ==================== MAIN APP LOGIC ====================

# Add stars to background
st.markdown(create_stars_html(), unsafe_allow_html=True)


# Add app mode selector to sidebar
with st.sidebar:
    st.image('assets/logo2.png', width=150)
    
    # Add the mode selector
    st.title("Applications")
    app_mode = st.radio(
        "Select Application",
        ["SAR Colorization", "SAR to Optical Translation"]
    )
    # Make sure this line is present to update the session state
    st.session_state.app_mode = app_mode
    # Add theme selector
    st.markdown("---")
    st.title("Appearance")
    theme = st.radio(
        "Select Theme",
        ["Dark", "Light"]
    )
    set_app_style(st.session_state.app_mode)
    # Make sure theme is properly stored in lowercase
    if theme.lower() != st.session_state.theme:
        st.session_state.theme = theme.lower()
        st.rerun()  # Force a rerun to apply the new theme
    
    st.markdown("---")

    # Sidebar content for SAR Colorization app
    if st.session_state.app_mode == "SAR Colorization":
        st.title("About")
        st.markdown("""
        ### SAR Image Colorization
        
        This application uses deep learning models to segment and colorize Synthetic Aperture Radar (SAR) images into land cover classes.
        
        #### Features:
        - Load pre-trained U-Net,DeepLabV3+ or SegNet models
        - Process single SAR images
        - Batch process multiple images
        - Visualize Pixel Level Classification with ESA WorldCover color scheme
        
        #### Developed by:
        Varun & Mokshyagna
        (NRSC, ISRO)
        
        #### Technologies:
        - TensorFlow/Keras
        - Streamlit
        - Rasterio
        - OpenCV
        
        #### Version:
        1.0.0
        """)
    # Sidebar content for the SAR to Optical app
    elif st.session_state.app_mode == "SAR to Optical Translation":
        st.header("Model Configuration")
        
        # Predefined model paths
        unet_weights_path = "models/unet_model.h5"
        generator_path = "models/final_generator.keras"
        
        # Display the paths that will be used
        st.info(f"U-Net Weights Path: {unet_weights_path}")
        
        use_generator = st.checkbox("Use Generator Model for Colorization", value=True)
        if use_generator:
            st.info(f"Generator Model Path: {generator_path}")
        else:
            generator_path = None
        
        # Load models button
        if st.button("Load Models"):
            with st.spinner("Loading models..."):
                gpu_status = setup_gpu()
                st.info(gpu_status)
                
                try:
                    unet_model, generator_model = load_models(unet_weights_path, generator_path if use_generator else None)
                    st.session_state['unet_model'] = unet_model
                    st.session_state['generator_model'] = generator_model
                    st.success("Models loaded successfully!")
                except Exception as e:
                    st.error(f"Error loading models: {e}")

        # Class information
        st.header("ESA WorldCover Classes")
        class_info = {
            'Trees': [0, 100, 0],
            'Shrubland': [255, 165, 0],
            'Grassland': [144, 238, 144],
            'Cropland': [255, 255, 0],
            'Built-up': [255, 0, 0],
            'Bare': [139, 69, 19],
            'Snow': [255, 255, 255],
            'Water': [0, 0, 255],
            'Wetland': [0, 139, 139],
            'Mangroves': [0, 255, 0],
            'Moss': [220, 220, 220]
        }
        
        for class_name, color in class_info.items():
            st.markdown(
                f'<div style="display: flex; align-items: center;">'
                f'<div style="width: 20px; height: 20px; background-color: rgb({color[0]}, {color[1]}, {color[2]}); margin-right: 10px;"></div>'
                f'<span>{class_name}</span>'
                f'</div>',
                unsafe_allow_html=True
            )
    
    st.markdown("---")
    st.markdown("© 2025 | All Rights Reserved")

# Main content area - conditional rendering based on app mode
if st.session_state.app_mode == "SAR Colorization":
    # SAR Colorization app
    st.markdown("""
    <div style="text-align: center; margin-bottom: 2rem; position: relative; z-index: 100;">
        <h1 style="color: #a78bfa; font-size: 3rem; font-weight: bold; text-shadow: 0 0 10px rgba(167, 139, 250, 0.5);">
            SAR Image Colorization
        </h1>
        <p style="color: #bfdbfe; font-size: 1.2rem;">
            Pixel Level Classification of Synthetic Aperture Radar images into land cover classes with deep learning
        </p>
    </div>
    """, unsafe_allow_html=True)

    # Create a card container
    st.markdown("<div class='card'>", unsafe_allow_html=True)

    # Create tabs
    # Create tabs
    tab1, tab2, tab3, tab4 = st.tabs(["📥 Load Model", "🖼️ Process Single Image", "📁 Process Multiple Images", "🔍 Sample Images"])


    # Tab 1: Load Model
    with tab1:
        st.markdown("<h3 style='color: #a78bfa;'>Load Segmentation Model</h3>", unsafe_allow_html=True)
        
        # Add model type selection
        model_type = st.selectbox(
            "Select model architecture",
            ["U-Net", "DeepLabV3+", "SegNet"],
            index=0,
            help="Select the architecture of the model to load"
        )
        
        # Update the model type in the segmentation object
        st.session_state.segmentation.model_type = model_type.lower().replace('-', '')
        
        # Define predefined model paths based on selected architecture
        model_paths = {
            "unet": "models/unet_model.h5",
            "deeplabv3+": "models/deeplabv3plus_model.h5",  # Add this key to match the session state
            "deeplabv3plus": "models/deeplabv3plus_model.h5",  # Keep this as a fallback
            "segnet": "models/segnet_model.h5"
        }
        
        selected_model_path = model_paths[st.session_state.segmentation.model_type]
        
        # Display the path that will be used
        st.info(f"Model will be loaded from: {selected_model_path}")
        
        # Load model button
        if st.button("Load Model", key="load_model_btn"):
            with st.spinner(f"Loading {model_type} model..."):
                try:
                    # Load the model from the predefined path
                    st.session_state.segmentation.load_trained_model(selected_model_path)
                    st.session_state.model_loaded = True
                    st.success("Model loaded successfully!")
                except Exception as e:
                    st.error(f"Error loading model: {str(e)}")
        
        # Display model information if loaded
        if st.session_state.model_loaded:
            st.markdown("<div class='card'>", unsafe_allow_html=True)
            st.markdown("<h4 style='color: #a78bfa;'>Model Information</h4>", unsafe_allow_html=True)
            
            col1, col2, col3 = st.columns(3)
            with col1:
                st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                # Display the correct model architecture based on the detected model type
                model_arch_map = {
                    'unet': "U-Net",
                    'deeplabv3plus': "DeepLabV3+",
                    'segnet': "SegNet"
                }
                model_arch = model_arch_map.get(st.session_state.segmentation.model_type, "Unknown")
                st.markdown(f"<p class='metric-value'>{model_arch}</p>", unsafe_allow_html=True)
                st.markdown("<p class='metric-label'>Architecture</p>", unsafe_allow_html=True)
                st.markdown("</div>", unsafe_allow_html=True)
            
            with col2:
                st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                st.markdown("<p class='metric-value'>11</p>", unsafe_allow_html=True)
                st.markdown("<p class='metric-label'>Land Cover Classes</p>", unsafe_allow_html=True)
                st.markdown("</div>", unsafe_allow_html=True)
            
            with col3:
                st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                st.markdown("<p class='metric-value'>256 x 256</p>", unsafe_allow_html=True)
                st.markdown("<p class='metric-label'>Input Size</p>", unsafe_allow_html=True)
                st.markdown("</div>", unsafe_allow_html=True)
            
            # Display legend
            st.markdown("<h4 style='color: #a78bfa; margin-top: 20px;'>Land Cover Classes</h4>", unsafe_allow_html=True)
            legend_img = create_legend()
            st.image(legend_img, use_container_width=True)
            
            st.markdown("</div>", unsafe_allow_html=True)
        else:
            st.info("Please load a model to continue.")

    # Tab 2: Process Single Image
    with tab2:
        st.markdown("<h3 style='color: #a78bfa;'>Process Single SAR Image</h3>", unsafe_allow_html=True)
        
        if not st.session_state.model_loaded:
            st.warning("Please load a model in the 'Load Model' tab first.")
        else:
            st.markdown("<div class='upload-box'>", unsafe_allow_html=True)
            col1, col2 = st.columns(2)
            
            with col1:
                uploaded_file = st.file_uploader(
                    "Upload a SAR image (.tif or common image formats)", 
                    type=["tif", "tiff", "png", "jpg", "jpeg"],
                    key="single_sar_uploader"
                )
            
            with col2:
                # Add ground truth upload option
                ground_truth_file = st.file_uploader(
                    "Upload ground truth (optional)", 
                    type=["tif", "tiff", "png", "jpg", "jpeg"],
                    key="single_gt_uploader"
                )
                
            st.markdown("</div>", unsafe_allow_html=True)
            
            if uploaded_file is not None:
                if st.button("Process Image", key="process_single_btn"):
                    with st.spinner("Processing image..."):
                        # Load and process the image
                        try:
                            sar_data = st.session_state.segmentation.load_sar_data(uploaded_file.getvalue(), is_bytes=True)
                            
                            # Normalize for visualization
                            sar_normalized = sar_data.copy()
                            min_val = np.min(sar_normalized)
                            max_val = np.max(sar_normalized)
                            sar_normalized = ((sar_normalized - min_val) / (max_val - min_val) * 255).astype(np.uint8)
                            
                            # Make prediction
                            prediction = st.session_state.segmentation.predict(sar_data)
                            
                            # Process ground truth if provided
                            if ground_truth_file is not None:
                                try:
                                    # Load ground truth
                                    gt_data = st.session_state.segmentation.load_sar_data(ground_truth_file.getvalue(), is_bytes=True)
                                    
                                    # Ensure SAR is properly normalized for visualization
                                    if np.max(sar_normalized) > 1 or np.min(sar_normalized) < 0:
                                        # If it's in 0-255 range, normalize to -1 to 1
                                        sar_for_viz = (sar_normalized.astype(np.float32) / 127.5) - 1
                                    else:
                                        # It's already normalized properly
                                        sar_for_viz = sar_normalized
                                    
                                    # Create visualization with ground truth using ESA WorldCover colors
                                    result_buf, colored_gt, colored_pred, overlay = visualize_with_ground_truth(
                                        sar_for_viz, 
                                        gt_data, 
                                        prediction
                                    )
                                    
                                    # Display results with metrics
                                    st.markdown("<h4 style='color: #a78bfa;'>Segmentation Results with Ground Truth</h4>", unsafe_allow_html=True)
                                    st.image(result_buf, use_container_width=True)
                                    
                                    # Calculate metrics
                                    pred_class = np.argmax(prediction[0], axis=-1)
                                    gt_class = gt_data[:,:,0].astype(np.int32)
                                    
                                    # Normalize ground truth to match prediction classes if needed
                                    if np.max(gt_class) > 10:  # If using ESA WorldCover values
                                        # Map ESA values to 0-10 indices
                                        gt_mapped = np.zeros_like(gt_class)
                                        class_values = sorted(st.session_state.segmentation.class_definitions.values())
                                        for i, val in enumerate(class_values):
                                            gt_mapped[gt_class == val] = i
                                        gt_class = gt_mapped
                                    
                                    accuracy = np.mean(pred_class == gt_class) * 100
                                    
                                    # Display metrics
                                    st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                                    st.markdown(f"<p class='metric-value'>{accuracy:.2f}%</p>", unsafe_allow_html=True)
                                    st.markdown("<p class='metric-label'>Pixel Accuracy</p>", unsafe_allow_html=True)
                                    st.markdown("</div>", unsafe_allow_html=True)
                                    
                                    # Add download button for the result
                                    btn = st.download_button(
                                        label="Download Result",
                                        data=result_buf,
                                        file_name="segmentation_result_with_gt.png",
                                        mime="image/png",
                                        key="download_single_result_with_gt"
                                    )
                                except Exception as e:
                                    st.error(f"Error processing ground truth: {str(e)}")
                                    # Fall back to regular visualization without ground truth
                                    result_img = visualize_prediction(prediction, np.expand_dims(sar_normalized, axis=-1))
                                    st.markdown("<h4 style='color: #a78bfa;'>Segmentation Results</h4>", unsafe_allow_html=True)
                                    st.image(result_img, use_container_width=True)
                                    
                                    # Add download button for the result
                                    btn = st.download_button(
                                        label="Download Result",
                                        data=result_img,
                                        file_name="segmentation_result.png",
                                        mime="image/png",
                                        key="download_single_result"
                                    )
                            else:
                                # Regular visualization without ground truth
                                result_img = visualize_prediction(prediction, np.expand_dims(sar_normalized, axis=-1))
                                st.markdown("<h4 style='color: #a78bfa;'>Segmentation Results</h4>", unsafe_allow_html=True)
                                st.image(result_img, use_container_width=True)
                                
                                # Add download button for the result
                                btn = st.download_button(
                                    label="Download Result",
                                    data=result_img,
                                    file_name="segmentation_result.png",
                                    mime="image/png",
                                    key="download_single_result"
                                )
                        except Exception as e:
                            st.error(f"Error processing image: {str(e)}")

    # Tab 3: Process Multiple Images
    with tab3:
        st.markdown("<h3 style='color: #a78bfa;'>Process Multiple SAR Images</h3>", unsafe_allow_html=True)
        
        if not st.session_state.model_loaded:
            st.warning("Please load a model in the 'Load Model' tab first.")
        else:
            st.markdown("<div class='upload-box'>", unsafe_allow_html=True)
            
            # Add option for ground truth
            use_gt = st.checkbox("Include ground truth data", value=False)
            
            col1, col2 = st.columns(2)
            
            with col1:
                uploaded_files = st.file_uploader(
                    "Upload SAR images or a ZIP file containing images", 
                    type=["tif", "tiff", "png", "jpg", "jpeg", "zip"], 
                    accept_multiple_files=True,
                    key="batch_sar_uploader"
                )
            
            # Add ground truth uploader if option is selected
            gt_files = None
            if use_gt:
                with col2:
                    gt_files = st.file_uploader(
                        "Upload ground truth images or a ZIP file (must match SAR filenames)", 
                        type=["tif", "tiff", "png", "jpg", "jpeg", "zip"], 
                        accept_multiple_files=True,
                        key="batch_gt_uploader"
                    )
                    st.info("Ground truth filenames should match SAR image filenames")
            
            st.markdown("</div>", unsafe_allow_html=True)
            
            col1, col2 = st.columns([3, 1])
            
            with col1:
                max_images = st.slider("Maximum number of images to display", min_value=1, max_value=20, value=10)
            
            with col2:
                st.markdown("<br>", unsafe_allow_html=True)
                process_btn = st.button("Process Images", key="process_multi_btn")
            
            if process_btn and uploaded_files:
                # Clear previous results
                st.session_state.processed_images = []
                
                # Process uploaded files
                with st.spinner("Processing images..."):
                    # Create a temporary directory to extract zip files if needed
                    with tempfile.TemporaryDirectory() as temp_dir:
                        # Process each uploaded file
                        sar_image_files = []
                        gt_image_files = {}  # Dictionary to map SAR filenames to GT filenames
                        
                        # Process SAR files
                        for uploaded_file in uploaded_files:
                            if uploaded_file.name.lower().endswith('.zip'):
                                # Extract zip file
                                zip_path = os.path.join(temp_dir, uploaded_file.name)
                                with open(zip_path, 'wb') as f:
                                    f.write(uploaded_file.getvalue())
                                
                                with zipfile.ZipFile(zip_path, 'r') as zip_ref:
                                    zip_ref.extractall(os.path.join(temp_dir, 'sar'))
                                
                                # Find all image files in the extracted directory
                                for root, _, files in os.walk(os.path.join(temp_dir, 'sar')):
                                    for file in files:
                                        if file.lower().endswith(('.tif', '.tiff', '.png', '.jpg', '.jpeg')):
                                            sar_image_files.append(os.path.join(root, file))
                            else:
                                # Save the file to temp directory
                                file_path = os.path.join(temp_dir, 'sar', uploaded_file.name)
                                os.makedirs(os.path.dirname(file_path), exist_ok=True)
                                with open(file_path, 'wb') as f:
                                    f.write(uploaded_file.getvalue())
                                sar_image_files.append(file_path)
                        
                        # Process ground truth files if provided
                        if use_gt and gt_files:
                            for gt_file in gt_files:
                                if gt_file.name.lower().endswith('.zip'):
                                    # Extract zip file
                                    zip_path = os.path.join(temp_dir, gt_file.name)
                                    with open(zip_path, 'wb') as f:
                                        f.write(gt_file.getvalue())
                                    
                                    with zipfile.ZipFile(zip_path, 'r') as zip_ref:
                                        zip_ref.extractall(os.path.join(temp_dir, 'gt'))
                                    
                                    # Find all image files in the extracted directory
                                    for root, _, files in os.walk(os.path.join(temp_dir, 'gt')):
                                        for file in files:
                                            if file.lower().endswith(('.tif', '.tiff', '.png', '.jpg', '.jpeg')):
                                                # Map GT file to SAR file by filename
                                                gt_path = os.path.join(root, file)
                                                gt_image_files[os.path.basename(file)] = gt_path
                                else:
                                    # Save the file to temp directory
                                    file_path = os.path.join(temp_dir, 'gt', gt_file.name)
                                    os.makedirs(os.path.dirname(file_path), exist_ok=True)
                                    with open(file_path, 'wb') as f:
                                        f.write(gt_file.getvalue())
                                    gt_image_files[os.path.basename(gt_file.name)] = file_path
                        
                        # If there are too many images, randomly select a subset
                        if len(sar_image_files) > max_images:
                            st.info(f"Found {len(sar_image_files)} images. Randomly selecting {max_images} images to display.")
                            sar_image_files = random.sample(sar_image_files, max_images)
                        
                        # Process each image
                        progress_bar = st.progress(0)
                        
                        # Track overall metrics if ground truth is provided
                        if use_gt and gt_image_files:
                            overall_accuracy = []
                        
                        for i, image_path in enumerate(sar_image_files):
                            try:
                                # Update progress
                                progress_bar.progress((i + 1) / len(sar_image_files))
                                
                                # Load and process the SAR image
                                sar_data = st.session_state.segmentation.load_sar_data(image_path)
                                
                                # Normalize for visualization
                                sar_normalized = sar_data.copy()
                                min_val = np.min(sar_normalized)
                                max_val = np.max(sar_normalized)
                                sar_normalized = ((sar_normalized - min_val) / (max_val - min_val) * 255).astype(np.uint8)
                                
                                # Make prediction
                                prediction = st.session_state.segmentation.predict(sar_data)
                                
                                # Check if we have a matching ground truth file
                                image_basename = os.path.basename(image_path)
                                has_gt = image_basename in gt_image_files
                                
                                if has_gt and use_gt:
                                    # Load ground truth
                                    gt_path = gt_image_files[image_basename]
                                    gt_data = st.session_state.segmentation.load_sar_data(gt_path)
                                    
                                    if np.max(sar_normalized) > 1 or np.min(sar_normalized) < 0:
                                        # If it's in 0-255 range, normalize to -1 to 1
                                        sar_for_viz = (sar_normalized.astype(np.float32) / 127.5) - 1
                                    else:
                                        # It's already normalized properly
                                        sar_for_viz = sar_normalized

                                    # Create visualization with ground truth using ESA WorldCover colors
                                    result_buf, colored_gt, colored_pred, overlay = visualize_with_ground_truth(
                                        sar_for_viz,
                                        gt_data,
                                        prediction
                                    )
                                    
                                    # Calculate metrics
                                    pred_class = np.argmax(prediction[0], axis=-1)
                                    gt_class = gt_data[:,:,0].astype(np.int32)
                                    
                                    # Normalize ground truth to match prediction classes if needed
                                    if np.max(gt_class) > 10:  # If using ESA WorldCover values
                                        # Map ESA values to 0-10 indices
                                        gt_mapped = np.zeros_like(gt_class)
                                        class_values = sorted(st.session_state.segmentation.class_definitions.values())
                                        for i, val in enumerate(class_values):
                                            gt_mapped[gt_class == val] = i
                                        gt_class = gt_mapped
                                    
                                    accuracy = np.mean(pred_class == gt_class) * 100
                                    overall_accuracy.append(accuracy)
                                    
                                    # Add to processed images with metrics
                                    st.session_state.processed_images.append({
                                        'filename': os.path.basename(image_path),
                                        'result': result_buf,
                                        'accuracy': accuracy
                                    })
                                else:
                                    # Regular visualization without ground truth
                                    result_img = visualize_prediction(prediction, np.expand_dims(sar_normalized, axis=-1))
                                    
                                    # Add to processed images
                                    st.session_state.processed_images.append({
                                        'filename': os.path.basename(image_path),
                                        'result': result_img
                                    })
                            except Exception as e:
                                st.error(f"Error processing {os.path.basename(image_path)}: {str(e)}")
                        
                        # Clear progress bar
                        progress_bar.empty()
                
                # Display results
                if st.session_state.processed_images:
                    st.markdown("<h4 style='color: #a78bfa;'>Segmentation Results</h4>", unsafe_allow_html=True)
                    
                    # Display overall metrics if ground truth was provided
                    if use_gt and 'overall_accuracy' in locals() and overall_accuracy:
                        avg_accuracy = np.mean(overall_accuracy)
                        st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                        st.markdown(f"<p class='metric-value'>{avg_accuracy:.2f}%</p>", unsafe_allow_html=True)
                        st.markdown("<p class='metric-label'>Average Pixel Accuracy</p>", unsafe_allow_html=True)
                        st.markdown("</div>", unsafe_allow_html=True)
                    
                    # Create a zip file with all results
                    zip_buffer = io.BytesIO()
                    with zipfile.ZipFile(zip_buffer, 'w') as zip_file:
                        for i, img_data in enumerate(st.session_state.processed_images):
                            zip_file.writestr(f"result_{i+1}_{img_data['filename']}.png", img_data['result'].getvalue())
                    
                    # Add download button for all results
                    st.download_button(
                        label="Download All Results",
                        data=zip_buffer.getvalue(),
                        file_name="segmentation_results.zip",
                        mime="application/zip",
                        key="download_all_results"
                    )
                    
                    # Display each result
                    for i, img_data in enumerate(st.session_state.processed_images):
                        st.markdown(f"<h5 style='color: #bfdbfe;'>Image: {img_data['filename']}</h5>", unsafe_allow_html=True)
                        
                        # Display accuracy if available
                        if 'accuracy' in img_data:
                            st.markdown(f"<p style='color: #a78bfa;'>Pixel Accuracy: {img_data['accuracy']:.2f}%</p>", unsafe_allow_html=True)
                        
                        st.image(img_data['result'], use_container_width=True)
                        st.markdown("<hr style='border-color: rgba(147, 51, 234, 0.3);'>", unsafe_allow_html=True)
                else:
                    st.warning("No images were successfully processed.")
            elif process_btn:
                st.warning("Please upload at least one image file or ZIP archive.")

    # Tab 4: Sample Images
    with tab4:
        st.markdown("<h3 style='color: #a78bfa;'>Sample Images</h3>", unsafe_allow_html=True)
        
        if not st.session_state.model_loaded:
            st.warning("Please load a model in the 'Load Model' tab first.")
        else:
            st.markdown("<div class='card'>", unsafe_allow_html=True)
            
            # Get list of sample images
            import os
            sample_dir = "samples/SAR"
            if os.path.exists(sample_dir):
                sample_files = [f for f in os.listdir(sample_dir) if f.endswith(('.tif', '.tiff', '.png', '.jpg', '.jpeg'))]
            else:
                os.makedirs(sample_dir, exist_ok=True)
                os.makedirs("samples/OPTICAL", exist_ok=True)
                os.makedirs("samples/LABELS", exist_ok=True)
                sample_files = []
            
            if sample_files:
                # Create a dropdown to select sample images
                selected_sample = st.selectbox(
                    "Select a sample image",
                    sample_files,
                    key="sample_selector"
                )
                
                # Display the selected sample
                col1, col2, col3 = st.columns(3)
                
                with col1:
                    st.subheader("SAR Image")
                    sar_path = os.path.join("samples/SAR", selected_sample)
                    display_image(sar_path)

                                        
                with col2:
                    st.subheader("Optical Image (Ground Truth)")
                    # Try to find matching optical image
                    opt_path = os.path.join("samples/OPTICAL", selected_sample)
                    if os.path.exists(opt_path):
                        display_image(opt_path)
                    else:
                        st.info("No matching optical image found")
                #
                # Add this debugging code where you're trying to load the label image
                with col3:
                    st.subheader("Label Image")
                    samples_dir = "samples"
                    
                    # Try multiple possible label directories
                    possible_label_dirs = [
                        os.path.join(samples_dir, "labels"),
                        os.path.join(samples_dir, "label"),
                        os.path.join(samples_dir, "LABELS"),
                        os.path.join(samples_dir, "LABEL"),
                        os.path.join(samples_dir, "Labels"),
                        os.path.join(samples_dir, "Label"),
                        os.path.join(samples_dir, "gt"),
                        os.path.join(samples_dir, "GT"),
                        os.path.join(samples_dir, "ground_truth"),
                        os.path.join(samples_dir, "groundtruth")
                    ]
                    
                    # Try to find the label file
                    label_path = None
                    base_name = os.path.splitext(selected_sample)[0]
                    
                    # Try different extensions in all possible directories
                    for dir_path in possible_label_dirs:
                        if not os.path.exists(dir_path):
                            continue
                            
                        # Try exact match first
                        exact_path = os.path.join(dir_path, selected_sample)
                        if os.path.exists(exact_path):
                            label_path = exact_path
                            break
                            
                        # Try different extensions
                        for ext in ['.tif', '.tiff', '.png', '.jpg', '.jpeg', '.TIF', '.TIFF', '.PNG', '.JPG', '.JPEG']:
                            test_path = os.path.join(dir_path, base_name + ext)
                            if os.path.exists(test_path):
                                label_path = test_path
                                break
                                
                        # Try case-insensitive match
                        if not label_path:
                            for file in os.listdir(dir_path):
                                if os.path.splitext(file)[0].lower() == base_name.lower():
                                    label_path = os.path.join(dir_path, file)
                                    break
                        
                        if label_path:
                            break
                    
                    # Display the label image if found
                    # Replace the current label display code with this
                    if label_path and os.path.exists(label_path):
                        try:
                            # For ESA WorldCover labels, we need special handling
                            if label_path.lower().endswith(('.tif', '.tiff')):
                                with rasterio.open(label_path) as src:
                                    label_data = src.read(1)  # Read first band
                                    
                                    # Convert ESA WorldCover labels to colored image
                                    colors = get_esa_colors()  # This function should be defined in your code
                                    colored_label = np.zeros((label_data.shape[0], label_data.shape[1], 3), dtype=np.uint8)
                                    
                                    # Map ESA values to colors
                                    for class_idx, color in colors.items():
                                        # If using ESA WorldCover values (10, 20, 30, etc.)
                                        if np.max(label_data) > 10:
                                            # Map ESA values to 0-10 indices
                                            class_values = sorted(st.session_state.segmentation.class_definitions.values())
                                            for i, val in enumerate(class_values):
                                                if class_idx == i:
                                                    colored_label[label_data == val] = color
                                        else:
                                            # Direct mapping if values are already 0-10
                                            colored_label[label_data == class_idx] = color
                                    
                                    st.image(colored_label, use_container_width=True)
                            else:
                                # For regular image formats
                                display_image(label_path)
                        except Exception as e:
                            st.error(f"Error displaying label image: {str(e)}")
                            # Fallback to regular display
                            display_image(label_path)
                    else:
                        st.info("No matching label image found")


                # Add a button to process the selected sample
                if st.button("Process Selected Sample", key="process_sample_btn"):
                    with st.spinner("Processing sample image..."):
                        try:
                            # Load and process the SAR image
                            sar_data = st.session_state.segmentation.load_sar_data(sar_path)
                            
                            # Normalize for visualization
                            sar_normalized = sar_data.copy()
                            min_val = np.min(sar_normalized)
                            max_val = np.max(sar_normalized)
                            sar_normalized = ((sar_normalized - min_val) / (max_val - min_val) * 255).astype(np.uint8)
                            
                            # Make prediction
                            prediction = st.session_state.segmentation.predict(sar_data)
                            
                            # Check if label image exists for comparison
                            if os.path.exists(label_path):
                                # Load label image as ground truth
                                gt_data = st.session_state.segmentation.load_sar_data(label_path)
                                
                                # Ensure SAR is properly normalized for visualization
                                if np.max(sar_normalized) > 1 or np.min(sar_normalized) < 0:
                                    # If it's in 0-255 range, normalize to -1 to 1
                                    sar_for_viz = (sar_normalized.astype(np.float32) / 127.5) - 1
                                else:
                                    # It's already normalized properly
                                    sar_for_viz = sar_normalized
                                
                                # Create visualization with ground truth using ESA WorldCover colors
                                result_buf, colored_gt, colored_pred, overlay = visualize_with_ground_truth(
                                    sar_for_viz, 
                                    gt_data, 
                                    prediction
                                )
                                
                                # Display results with metrics
                                st.markdown("<h4 style='color: #a78bfa;'>Segmentation Results with Ground Truth</h4>", unsafe_allow_html=True)
                                st.image(result_buf, use_container_width=True)
                                
                                # Calculate metrics
                                pred_class = np.argmax(prediction[0], axis=-1)
                                gt_class = gt_data[:,:,0].astype(np.int32)
                                
                                # Normalize ground truth to match prediction classes if needed
                                if np.max(gt_class) > 10:  # If using ESA WorldCover values
                                    # Map ESA values to 0-10 indices
                                    gt_mapped = np.zeros_like(gt_class)
                                    class_values = sorted(st.session_state.segmentation.class_definitions.values())
                                    for i, val in enumerate(class_values):
                                        gt_mapped[gt_class == val] = i
                                    gt_class = gt_mapped
                                
                                accuracy = np.mean(pred_class == gt_class) * 100
                                
                                # Display metrics
                                st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                                st.markdown(f"<p class='metric-value'>{accuracy:.2f}%</p>", unsafe_allow_html=True)
                                st.markdown("<p class='metric-label'>Pixel Accuracy</p>", unsafe_allow_html=True)
                                st.markdown("</div>", unsafe_allow_html=True)
                                
                                # Add download button for the result
                                btn = st.download_button(
                                    label="Download Result",
                                    data=result_buf,
                                    file_name=f"sample_result_{selected_sample}.png",
                                    mime="image/png",
                                    key="download_sample_result_with_gt"
                                )
                            else:
                                # Regular visualization without ground truth
                                result_img = visualize_prediction(prediction, np.expand_dims(sar_normalized, axis=-1))
                                st.markdown("<h4 style='color: #a78bfa;'>Segmentation Results</h4>", unsafe_allow_html=True)
                                st.image(result_img, use_container_width=True)
                                
                                # Add download button for the result
                                btn = st.download_button(
                                    label="Download Result",
                                    data=result_img,
                                    file_name=f"sample_result_{selected_sample}.png",
                                    mime="image/png",
                                    key="download_sample_result"
                                )
                        except Exception as e:
                            st.error(f"Error processing sample image: {str(e)}")
            else:
                st.info("No sample images found. Please add some images to the 'samples/SAR' directory.")
            
            

    # Close the card container
    st.markdown("</div>", unsafe_allow_html=True)

elif st.session_state.app_mode == "SAR to Optical Translation":
    # SAR to Optical Translation app
    st.markdown("""
    <div style="text-align: center; margin-bottom: 2rem; position: relative; z-index: 100;">
        <h1 style="color: #a78bfa; font-size: 3rem; font-weight: bold; text-shadow: 0 0 10px rgba(167, 139, 250, 0.5);">
            SAR to Optical Translation
        </h1>
        <p style="color: #bfdbfe; font-size: 1.2rem;">
            Convert Synthetic Aperture Radar images to optical-like imagery using deep learning
        </p>
    </div>
    """, unsafe_allow_html=True)
    
    # Create a card container
    st.markdown("<div class='card'>", unsafe_allow_html=True)
    
    # Check if models are loaded
    models_loaded = 'unet_model' in st.session_state
    
    if not models_loaded:
        st.warning("Please load the models from the sidebar first.")
    else:
        st.success("Models loaded successfully! You can now process SAR images.")
        
        # Create tabs for single image and batch processing
        # Create tabs for single image and batch processing
        tab1, tab2, tab3 = st.tabs(["Process Single Image", "Batch Processing", "Sample Images"])

        
        with tab1:
            st.markdown("<h3 style='color: #a78bfa;'>Upload SAR Image</h3>", unsafe_allow_html=True)
            
            # Create two columns for SAR and optional ground truth
            # Create two columns for SAR and optional ground truth
            col1, col2 = st.columns(2)
            
            with col1:
                st.markdown("<div class='upload-box'>", unsafe_allow_html=True)
                uploaded_file = st.file_uploader(
                    "Upload a SAR image (.tif or common image formats)", 
                    type=["tif", "tiff", "png", "jpg", "jpeg"],
                    key="sar_optical_uploader"
                )
                st.markdown("</div>", unsafe_allow_html=True)
            
            # Add ground truth upload option
            with col2:
                st.markdown("<div class='upload-box'>", unsafe_allow_html=True)
                gt_file = st.file_uploader(
                    "Upload ground truth optical image (optional)", 
                    type=["tif", "tiff", "png", "jpg", "jpeg"],
                    key="optical_gt_uploader"
                )
                st.markdown("</div>", unsafe_allow_html=True)
            
            if uploaded_file is not None:
                # Process button
                if st.button("Generate Optical-like Image", key="generate_optical_btn"):
                    with st.spinner("Processing image..."):
                        try:
                            # Load and process the SAR image
                            sar_batch, sar_image = load_sar_image(uploaded_file)
                            
                            if sar_batch is not None:
                                # Process with models
                                seg_mask, colorized = process_image(
                                    sar_batch,
                                    st.session_state['unet_model'],
                                    st.session_state.get('generator_model')
                                )
                                
                                # Visualize results
                                sar_rgb, colored_pred, overlay, colorized_img = visualize_results(
                                    sar_image, seg_mask, colorized
                                )
                                
                                # Display results
                                st.header("Results")
                                
                                # If ground truth is provided, include it in visualization
                                if gt_file is not None:
                                    try:
                                        # Load ground truth image
                                        with tempfile.NamedTemporaryFile(delete=False, suffix='.tif') as tmp_file:
                                            tmp_file.write(gt_file.getbuffer())
                                            tmp_file_path = tmp_file.name

                                        try:
                                            # Try to open with rasterio
                                            with rasterio.open(tmp_file_path) as src:
                                                gt_image = src.read()
                                                # Debug info
                                                st.info(f"Ground truth shape: {gt_image.shape}, dtype: {gt_image.dtype}, min: {np.min(gt_image)}, max: {np.max(gt_image)}")
                                                
                                                if gt_image.shape[0] == 3:  # RGB image
                                                    gt_image = np.transpose(gt_image, (1, 2, 0))
                                                else:  # Single band
                                                    gt_image = src.read(1)
                                                    # Check if the image is all zeros or all ones
                                                    if np.all(gt_image == 0) or np.all(gt_image == 1):
                                                        st.warning("Ground truth image appears to be blank (all zeros or ones)")
                                                    
                                                    # Convert to RGB for display
                                                    gt_image = np.expand_dims(gt_image, axis=-1)
                                                    gt_image = np.repeat(gt_image, 3, axis=-1)
                                        except Exception as rasterio_error:
                                            st.warning(f"Rasterio failed: {str(rasterio_error)}. Trying PIL...")
                                            try:
                                                # If rasterio fails, try PIL
                                                gt_image = np.array(Image.open(tmp_file_path).convert('RGB'))
                                                # Debug info
                                                st.info(f"Ground truth shape (PIL): {gt_image.shape}, dtype: {gt_image.dtype}, min: {np.min(gt_image)}, max: {np.max(gt_image)}")
                                                
                                                # Check if the image is all white
                                                if np.all(gt_image > 250):
                                                    st.warning("Ground truth image appears to be all white")
                                            except Exception as pil_error:
                                                st.error(f"Both rasterio and PIL failed to load the ground truth: {str(pil_error)}")
                                                raise

                                        # Clean up the temporary file
                                        os.unlink(tmp_file_path)

                                        # Resize if needed
                                        if gt_image.shape[:2] != (256, 256):
                                            gt_image = cv2.resize(gt_image, (256, 256))

                                        # Normalize if needed - make sure values are in 0-255 range for display
                                        if gt_image.dtype != np.uint8:
                                            if np.max(gt_image) > 1.0 and np.max(gt_image) <= 255:
                                                gt_image = gt_image.astype(np.uint8)
                                            elif np.max(gt_image) <= 1.0:
                                                gt_image = (gt_image * 255).astype(np.uint8)
                                            else:
                                                # Scale to 0-255
                                                gt_min, gt_max = np.min(gt_image), np.max(gt_image)
                                                gt_image = ((gt_image - gt_min) / (gt_max - gt_min) * 255).astype(np.uint8)

                                        
                                        # Create 4-panel visualization with ground truth
                                        fig, axes = plt.subplots(1, 4, figsize=(16, 4))
                                        
                                        # Original SAR
                                        axes[0].imshow(sar_rgb, cmap='gray')
                                        axes[0].set_title('Original SAR', color='white')
                                        axes[0].axis('off')
                                        
                                        # Ground Truth
                                        axes[1].imshow(gt_image)
                                        axes[1].set_title('Ground Truth', color='white')
                                        axes[1].axis('off')
                                        
                                        # Segmentation
                                        axes[2].imshow(colored_pred)
                                        axes[2].set_title('Segmentation', color='white')
                                        axes[2].axis('off')
                                        
                                        # Generated Image
                                        if colorized_img is not None:
                                            # Convert from -1,1 to 0,1 range
                                            colorized_display = (colorized_img * 0.5) + 0.5
                                            axes[3].imshow(colorized_display)
                                        else:
                                            axes[3].imshow(overlay)
                                        axes[3].set_title('Generated Image', color='white')
                                        axes[3].axis('off')
                                        
                                        # Set dark background
                                        fig.patch.set_facecolor('#0a0a1f')
                                        for ax in axes:
                                            ax.set_facecolor('#0a0a1f')
                                        
                                        plt.tight_layout()
                                        
                                        # Display the figure
                                        st.pyplot(fig)
                                        
                                        # Calculate metrics if ground truth is provided
                                        if colorized_img is not None:
                                            # Normalize both images to 0-1 range for comparison
                                            colorized_norm = (colorized_img * 0.5) + 0.5
                                            gt_norm = gt_image.astype(np.float32) / 255.0
                                            
                                            # Calculate PSNR
                                            mse = np.mean((colorized_norm - gt_norm) ** 2)
                                            psnr = 20 * np.log10(1.0 / np.sqrt(mse))
                                            
                                            # Calculate SSIM
                                            from skimage.metrics import structural_similarity as ssim

                                            try:
                                                # Check image dimensions and set appropriate window size
                                                min_dim = min(colorized_norm.shape[0], colorized_norm.shape[1])
                                                win_size = min(7, min_dim - (min_dim % 2) + 1)  # Ensure it's odd and smaller than min dimension
                                                
                                                ssim_value = ssim(
                                                    colorized_norm, 
                                                    gt_norm, 
                                                    win_size=win_size,  # Explicitly set window size
                                                    channel_axis=2,     # Specify channel axis for RGB images
                                                    data_range=1.0
                                                )
                                            except Exception as e:
                                                st.warning(f"Could not calculate SSIM: {str(e)}")
                                                ssim_value = 0.0  # Default value if calculation fails

                                            
                                            # Display metrics
                                            col1, col2 = st.columns(2)
                                            with col1:
                                                st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                                                st.markdown(f"<p class='metric-value'>{psnr:.2f}</p>", unsafe_allow_html=True)
                                                st.markdown("<p class='metric-label'>PSNR (dB)</p>", unsafe_allow_html=True)
                                                st.markdown("</div>", unsafe_allow_html=True)
                                            
                                            with col2:
                                                st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                                                st.markdown(f"<p class='metric-value'>{ssim_value:.4f}</p>", unsafe_allow_html=True)
                                                st.markdown("<p class='metric-label'>SSIM</p>", unsafe_allow_html=True)
                                                st.markdown("</div>", unsafe_allow_html=True)
                                    except Exception as e:
                                        st.error(f"Error processing ground truth: {str(e)}")
                                        # Fall back to regular visualization
                                        col1, col2, col3 = st.columns(3)
                                        
                                        with col1:
                                            st.subheader("Original SAR Image")
                                            st.image(sar_rgb, use_container_width=True)
                                        
                                        with col2:
                                            st.subheader("Predicted Segmentation")
                                            st.image(colored_pred, use_container_width=True)
                                        
                                        with col3:
                                            st.subheader("Colorized SAR")
                                            st.image(overlay, use_container_width=True)
                                else:
                                    # Regular 3-panel visualization without ground truth
                                    col1, col2, col3 = st.columns(3)
                                    
                                    with col1:
                                        st.subheader("Original SAR Image")
                                        st.image(sar_rgb, use_container_width=True)
                                    
                                    with col2:
                                        st.subheader("Predicted Segmentation")
                                        st.image(colored_pred, use_container_width=True)
                                    
                                    with col3:
                                        st.subheader("Colorized SAR")
                                        st.image(overlay, use_container_width=True)
                                
                                # Display colorized image if available
                                if colorized_img is not None:
                                    st.header("Translated Optical Image")
                                    # Convert from -1,1 to 0,1 range
                                    colorized_display = (colorized_img * 0.5) + 0.5
                                    
                                    # Create a figure with controlled size
                                    fig, ax = plt.subplots(figsize=(6, 6))
                                    ax.imshow(colorized_display)
                                    ax.axis('off')
                                    
                                    # Use the figure for display instead of direct image
                                    st.pyplot(fig, use_container_width=False)
                                    
                                    # Add download buttons
                                    col1, col2 = st.columns(2)
                                    
                                    with col1:
                                        # Save segmentation image
                                        seg_buf = io.BytesIO()
                                        plt.imsave(seg_buf, colored_pred, format='png')
                                        seg_buf.seek(0)
                                        
                                        st.download_button(
                                            label="Download Segmentation",
                                            data=seg_buf,
                                            file_name="segmentation.png",
                                            mime="image/png",
                                            key="download_seg"
                                        )
                                    
                                    with col2:
                                        # Save generated image
                                        gen_buf = io.BytesIO()
                                        plt.imsave(gen_buf, colorized_display, format='png')
                                        gen_buf.seek(0)
                                        
                                        st.download_button(
                                            label="Download Optical-like Image",
                                            data=gen_buf,
                                            file_name="optical_like.png",
                                            mime="image/png",
                                            key="download_optical"
                                        )
                        except Exception as e:
                            st.error(f"Error processing image: {str(e)}")
        
        # Batch processing tab
        with tab2:
            st.markdown("<h3 style='color: #a78bfa;'>Batch Process SAR Images</h3>", unsafe_allow_html=True)
            
            st.markdown("<div class='upload-box'>", unsafe_allow_html=True)
            
            # Add option for ground truth
            use_gt = st.checkbox("Include ground truth data", value=False)
            
            col1, col2 = st.columns(2)
            
            with col1:
                batch_files = st.file_uploader(
                    "Upload SAR images or a ZIP file containing images", 
                    type=["tif", "tiff", "png", "jpg", "jpeg", "zip"], 
                    accept_multiple_files=True,
                    key="batch_sar_optical_uploader"
                )
            
            # Add ground truth uploader if option is selected
            batch_gt_files = None
            if use_gt:
                with col2:
                    batch_gt_files = st.file_uploader(
                        "Upload ground truth optical images or a ZIP file (must match SAR filenames)", 
                        type=["tif", "tiff", "png", "jpg", "jpeg", "zip"], 
                        accept_multiple_files=True,
                        key="batch_optical_gt_uploader"
                    )
                    st.info("Ground truth filenames should match SAR image filenames")
            
            st.markdown("</div>", unsafe_allow_html=True)
            
            col1, col2 = st.columns([3, 1])
            
            with col1:
                max_images = st.slider("Maximum number of images to display", min_value=1, max_value=20, value=5)
            
            with col2:
                st.markdown("<br>", unsafe_allow_html=True)
                batch_process_btn = st.button("Process Images", key="batch_process_btn")
            
            if batch_process_btn and batch_files:
                # Clear previous results
                if 'batch_results' not in st.session_state:
                    st.session_state.batch_results = []
                else:
                    st.session_state.batch_results = []
                
                # Process uploaded files
                with st.spinner("Processing images..."):
                    # Create a temporary directory to extract zip files if needed
                    with tempfile.TemporaryDirectory() as temp_dir:
                        # Process each uploaded file
                        sar_image_files = []
                        gt_image_files = {}  # Dictionary to map SAR filenames to GT filenames
                        
                        # Process SAR files
                        for uploaded_file in batch_files:
                            if uploaded_file.name.lower().endswith('.zip'):
                                # Extract zip file
                                zip_path = os.path.join(temp_dir, uploaded_file.name)
                                with open(zip_path, 'wb') as f:
                                    f.write(uploaded_file.getvalue())
                                
                                with zipfile.ZipFile(zip_path, 'r') as zip_ref:
                                    zip_ref.extractall(os.path.join(temp_dir, 'sar'))
                                
                                # Find all image files in the extracted directory
                                for root, _, files in os.walk(os.path.join(temp_dir, 'sar')):
                                    for file in files:
                                        if file.lower().endswith(('.tif', '.tiff', '.png', '.jpg', '.jpeg')):
                                            sar_image_files.append(os.path.join(root, file))
                            else:
                                # Save the file to temp directory
                                file_path = os.path.join(temp_dir, 'sar', uploaded_file.name)
                                os.makedirs(os.path.dirname(file_path), exist_ok=True)
                                with open(file_path, 'wb') as f:
                                    f.write(uploaded_file.getvalue())
                                sar_image_files.append(file_path)
                        
                        # Process ground truth files if provided
                        if use_gt and batch_gt_files:
                            for gt_file in batch_gt_files:
                                if gt_file.name.lower().endswith('.zip'):
                                    # Extract zip file
                                    zip_path = os.path.join(temp_dir, gt_file.name)
                                    with open(zip_path, 'wb') as f:
                                        f.write(gt_file.getvalue())
                                    
                                    with zipfile.ZipFile(zip_path, 'r') as zip_ref:
                                        zip_ref.extractall(os.path.join(temp_dir, 'gt'))
                                    
                                    # Find all image files in the extracted directory
                                    for root, _, files in os.walk(os.path.join(temp_dir, 'gt')):
                                        for file in files:
                                            if file.lower().endswith(('.tif', '.tiff', '.png', '.jpg', '.jpeg')):
                                                # Map GT file to SAR file by filename
                                                gt_path = os.path.join(root, file)
                                                gt_image_files[os.path.basename(file)] = gt_path
                                else:
                                    # Save the file to temp directory
                                    file_path = os.path.join(temp_dir, 'gt', gt_file.name)
                                    os.makedirs(os.path.dirname(file_path), exist_ok=True)
                                    with open(file_path, 'wb') as f:
                                        f.write(gt_file.getvalue())
                                    gt_image_files[os.path.basename(gt_file.name)] = file_path
                        
                        # If there are too many images, randomly select a subset
                        if len(sar_image_files) > max_images:
                            st.info(f"Found {len(sar_image_files)} images. Randomly selecting {max_images} images to display.")
                            sar_image_files = random.sample(sar_image_files, max_images)
                        
                        # Process each image
                        progress_bar = st.progress(0)
                        
                        # Track overall metrics if ground truth is provided
                        if use_gt and gt_image_files:
                            overall_psnr = []
                            overall_ssim = []
                        
                        for i, image_path in enumerate(sar_image_files):
                            try:
                                # Update progress
                                progress_bar.progress((i + 1) / len(sar_image_files))
                                
                                # Load and process the SAR image
                                with open(image_path, 'rb') as f:
                                    file_bytes = f.read()
                                
                                sar_batch, sar_image = load_sar_image(io.BytesIO(file_bytes))
                                
                                if sar_batch is not None:
                                    # Process with models
                                    seg_mask, colorized = process_image(
                                        sar_batch,
                                        st.session_state['unet_model'],
                                        st.session_state.get('generator_model')
                                    )
                                    
                                    # Visualize results
                                    sar_rgb, colored_pred, overlay, colorized_img = visualize_results(
                                        sar_image, seg_mask, colorized
                                    )
                                    
                                    # Check if we have a matching ground truth file
                                    image_basename = os.path.basename(image_path)
                                    has_gt = image_basename in gt_image_files
                                    
                                    if has_gt and use_gt:
                                        # Load ground truth
                                        gt_path = gt_image_files[image_basename]
                                        try:
                                            # Try to open with rasterio
                                            with rasterio.open(gt_path) as src:
                                                gt_image = src.read()
                                                
                                                if gt_image.shape[0] == 3:  # RGB image
                                                    gt_image = np.transpose(gt_image, (1, 2, 0))
                                                else:  # Single band
                                                    gt_image = src.read(1)
                                                    
                                                    # Convert to RGB for display
                                                    gt_image = np.expand_dims(gt_image, axis=-1)
                                                    gt_image = np.repeat(gt_image, 3, axis=-1)
                                        except Exception as rasterio_error:
                                            try:
                                                # If rasterio fails, try PIL
                                                gt_image = np.array(Image.open(gt_path).convert('RGB'))
                                            except Exception as pil_error:
                                                st.error(f"Both rasterio and PIL failed to load the ground truth: {str(pil_error)}")
                                                raise

                                        # Resize if needed
                                        if gt_image.shape[:2] != (256, 256):
                                            gt_image = cv2.resize(gt_image, (256, 256))

                                        # Normalize if needed - make sure values are in 0-255 range for display
                                        if gt_image.dtype != np.uint8:
                                            if np.max(gt_image) > 1.0 and np.max(gt_image) <= 255:
                                                gt_image = gt_image.astype(np.uint8)
                                            elif np.max(gt_image) <= 1.0:
                                                gt_image = (gt_image * 255).astype(np.uint8)
                                            else:
                                                # Scale to 0-255
                                                gt_min, gt_max = np.min(gt_image), np.max(gt_image)
                                                gt_image = ((gt_image - gt_min) / (gt_max - gt_min) * 255).astype(np.uint8)

                                        
                                        # Create visualization with ground truth
                                        fig, axes = plt.subplots(1, 4, figsize=(16, 4))
                                        
                                        # Original SAR
                                        axes[0].imshow(sar_rgb, cmap='gray')
                                        axes[0].set_title('Original SAR', color='white')
                                        axes[0].axis('off')
                                        
                                        # Ground Truth
                                        axes[1].imshow(gt_image)
                                        axes[1].set_title('Ground Truth', color='white')
                                        axes[1].axis('off')
                                        
                                        # Segmentation
                                        axes[2].imshow(colored_pred)
                                        axes[2].set_title('Segmentation', color='white')
                                        axes[2].axis('off')
                                        
                                        # Generated Image
                                        if colorized_img is not None:
                                            # Convert from -1,1 to 0,1 range
                                            colorized_display = (colorized_img * 0.5) + 0.5
                                            axes[3].imshow(colorized_display)
                                        else:
                                            axes[3].imshow(overlay)
                                        axes[3].set_title('Generated Image', color='white')
                                        axes[3].axis('off')
                                        
                                        # Set dark background
                                        fig.patch.set_facecolor('#0a0a1f')
                                        for ax in axes:
                                            ax.set_facecolor('#0a0a1f')
                                        
                                        plt.tight_layout()
                                        
                                        # Convert plot to image
                                        result_buf = io.BytesIO()
                                        plt.savefig(result_buf, format='png', facecolor='#0a0a1f', bbox_inches='tight')
                                        result_buf.seek(0)
                                        plt.close(fig)
                                        
                                        # Calculate metrics if colorized image is available
                                        metrics = {'psnr': 0.0, 'ssim': 0.0}  # Default values
                                        if colorized_img is not None:
                                            try:
                                                # Normalize both images to 0-1 range for comparison
                                                colorized_norm = (colorized_img * 0.5) + 0.5
                                                gt_norm = gt_image.astype(np.float32) / 255.0
                                                
                                                # Calculate PSNR
                                                mse = np.mean((colorized_norm - gt_norm) ** 2)
                                                if mse > 0:
                                                    psnr = 20 * np.log10(1.0 / np.sqrt(mse))
                                                    metrics['psnr'] = psnr
                                                    overall_psnr.append(psnr)
                                                
                                                # Calculate SSIM with explicit window size
                                                from skimage.metrics import structural_similarity as ssim
                                                
                                                # Check image dimensions and set appropriate window size
                                                min_dim = min(colorized_norm.shape[0], colorized_norm.shape[1])
                                                win_size = min(7, min_dim - (min_dim % 2) + 1)  # Ensure it's odd and smaller than min dimension
                                                
                                                ssim_value = ssim(
                                                    colorized_norm, 
                                                    gt_norm, 
                                                    win_size=win_size,  # Explicitly set window size
                                                    channel_axis=2,     # Specify channel axis for RGB images
                                                    data_range=1.0
                                                )
                                                metrics['ssim'] = ssim_value
                                                overall_ssim.append(ssim_value)
                                            except Exception as e:
                                                st.warning(f"Could not calculate metrics for {os.path.basename(image_path)}: {str(e)}")

                                        
                                        # Save generated image for download
                                        gen_buf = io.BytesIO()
                                        if colorized_img is not None:
                                            plt.imsave(gen_buf, colorized_display, format='png')
                                        else:
                                            plt.imsave(gen_buf, overlay, format='png')
                                        gen_buf.seek(0)
                                        
                                        # Add to batch results
                                        st.session_state.batch_results.append({
                                            'filename': os.path.basename(image_path),
                                            'result': result_buf,
                                            'generated': gen_buf,
                                            'metrics': metrics
                                        })
                                    else:
                                        # Regular visualization without ground truth
                                        fig, axes = plt.subplots(1, 3, figsize=(12, 4))
                                        
                                        # Original SAR
                                        axes[0].imshow(sar_rgb, cmap='gray')
                                        axes[0].set_title('Original SAR', color='white')
                                        axes[0].axis('off')
                                        
                                        # Segmentation
                                        axes[1].imshow(colored_pred)
                                        axes[1].set_title('Segmentation', color='white')
                                        axes[1].axis('off')
                                        
                                        # Generated Image
                                        if colorized_img is not None:
                                            # Convert from -1,1 to 0,1 range
                                            colorized_display = (colorized_img * 0.5) + 0.5
                                            axes[2].imshow(colorized_display)
                                        else:
                                            axes[2].imshow(overlay)
                                        axes[2].set_title('Generated Image', color='white')
                                        axes[2].axis('off')
                                        
                                        # Set dark background
                                        fig.patch.set_facecolor('#0a0a1f')
                                        for ax in axes:
                                            ax.set_facecolor('#0a0a1f')
                                        
                                        plt.tight_layout()
                                        
                                        # Convert plot to image
                                        result_buf = io.BytesIO()
                                        plt.savefig(result_buf, format='png', facecolor='#0a0a1f', bbox_inches='tight')
                                        result_buf.seek(0)
                                        plt.close(fig)
                                        
                                        # Save generated image for download
                                        gen_buf = io.BytesIO()
                                        if colorized_img is not None:
                                            plt.imsave(gen_buf, colorized_display, format='png')
                                        else:
                                            plt.imsave(gen_buf, overlay, format='png')
                                        gen_buf.seek(0)
                                        
                                        # Add to batch results
                                        st.session_state.batch_results.append({
                                            'filename': os.path.basename(image_path),
                                            'result': result_buf,
                                            'generated': gen_buf
                                        })
                            except Exception as e:
                                st.error(f"Error processing {os.path.basename(image_path)}: {str(e)}")
                        
                        # Clear progress bar
                        progress_bar.empty()
                
                # Display results
                if st.session_state.batch_results:
                    st.markdown("<h4 style='color: #a78bfa;'>Translation Results</h4>", unsafe_allow_html=True)
                    
                    # Display overall metrics if ground truth was provided
                    if use_gt and 'overall_psnr' in locals() and overall_psnr:
                        avg_psnr = np.mean(overall_psnr)
                        avg_ssim = np.mean(overall_ssim)
                        
                        col1, col2 = st.columns(2)
                        with col1:
                            st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                            st.markdown(f"<p class='metric-value'>{avg_psnr:.2f}</p>", unsafe_allow_html=True)
                            st.markdown("<p class='metric-label'>Average PSNR (dB)</p>", unsafe_allow_html=True)
                            st.markdown("</div>", unsafe_allow_html=True)
                        
                        with col2:
                            st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                            st.markdown(f"<p class='metric-value'>{avg_ssim:.4f}</p>", unsafe_allow_html=True)
                            st.markdown("<p class='metric-label'>Average SSIM</p>", unsafe_allow_html=True)
                            st.markdown("</div>", unsafe_allow_html=True)
                    
                    # Create a zip file with all results
                    zip_buffer = io.BytesIO()
                    with zipfile.ZipFile(zip_buffer, 'w') as zip_file:
                        for i, result in enumerate(st.session_state.batch_results):
                            # Add visualization
                            zip_file.writestr(f"result_{i+1}_{result['filename']}.png", result['result'].getvalue())
                            # Add generated image
                            zip_file.writestr(f"generated_{i+1}_{result['filename']}.png", result['generated'].getvalue())
                    
                    # Add download button for all results
                    st.download_button(
                        label="Download All Results",
                        data=zip_buffer.getvalue(),
                        file_name="translation_results.zip",
                        mime="application/zip",
                        key="download_all_translation_results"
                    )
                    
                    # Display each result
                    for i, result in enumerate(st.session_state.batch_results):
                        st.markdown(f"<h5 style='color: #bfdbfe;'>Image: {result['filename']}</h5>", unsafe_allow_html=True)
                        
                        # Display metrics if available
                        if 'metrics' in result:
                            col1, col2 = st.columns(2)
                            with col1:
                                st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                                if 'psnr' in result['metrics']:
                                    st.markdown(f"<p class='metric-value'>{result['metrics']['psnr']:.2f}</p>", unsafe_allow_html=True)
                                else:
                                    st.markdown("<p class='metric-value'>N/A</p>", unsafe_allow_html=True)
                                st.markdown("<p class='metric-label'>PSNR (dB)</p>", unsafe_allow_html=True)
                                st.markdown("</div>", unsafe_allow_html=True)
                            
                            with col2:
                                st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                                if 'ssim' in result['metrics']:
                                    st.markdown(f"<p class='metric-value'>{result['metrics']['ssim']:.4f}</p>", unsafe_allow_html=True)
                                else:
                                    st.markdown("<p class='metric-value'>N/A</p>", unsafe_allow_html=True)
                                st.markdown("<p class='metric-label'>SSIM</p>", unsafe_allow_html=True)
                                st.markdown("</div>", unsafe_allow_html=True)

                        
                        st.image(result['result'], use_container_width=True)
                        
                        # Add download button for individual result
                        col1, col2 = st.columns(2)
                        with col1:
                            st.download_button(
                                label="Download Visualization",
                                data=result['result'].getvalue(),
                                file_name=f"result_{result['filename']}.png",
                                mime="image/png",
                                key=f"download_viz_{i}"
                            )
                        
                        with col2:
                            st.download_button(
                                label="Download Generated Image",
                                data=result['generated'].getvalue(),
                                file_name=f"generated_{result['filename']}.png",
                                mime="image/png",
                                key=f"download_gen_{i}"
                            )
                        
                        st.markdown("<hr style='border-color: rgba(147, 51, 234, 0.3);'>", unsafe_allow_html=True)
                else:
                    st.warning("No images were successfully processed.")
            elif batch_process_btn:
                st.warning("Please upload at least one image file or ZIP archive.")
        # Tab 3: Sample Images
        with tab3:
            st.markdown("<h3 style='color: #a78bfa;'>Sample Images</h3>", unsafe_allow_html=True)
            st.markdown("<div class='card'>", unsafe_allow_html=True)
            
            # Get list of sample images
            import os
            sample_dir = "samples/SAR"
            if os.path.exists(sample_dir):
                sample_files = [f for f in os.listdir(sample_dir) if f.endswith(('.tif', '.tiff', '.png', '.jpg', '.jpeg'))]
            else:
                os.makedirs(sample_dir, exist_ok=True)
                os.makedirs("samples/OPTICAL", exist_ok=True)
                os.makedirs("samples/LABELS", exist_ok=True)
                sample_files = []
            
            if sample_files and 'unet_model' in st.session_state:
                # Create a dropdown to select sample images
                selected_sample = st.selectbox(
                    "Select a sample image",
                    sample_files,
                    key="optical_sample_selector"
                )
                
                # Display the selected sample
                col1, col2 = st.columns(2)
                
                with col1:
                    st.subheader("SAR Image")
                    sar_path = os.path.join("samples/SAR", selected_sample)
                    display_image(sar_path)


                with col2:
                    st.subheader("Optical Image (Ground Truth)")
                    # Try to find matching optical image
                    opt_path = os.path.join("samples/OPTICAL", selected_sample)
                    if os.path.exists(opt_path):
                        display_image(opt_path)
                    else:
                        st.info("No matching optical image found")
                
                # Add a button to process the selected sample
                if st.button("Generate Optical-like Image", key="process_optical_sample_btn"):
                    with st.spinner("Processing sample image..."):
                        try:
                            # Load the SAR image
                            with open(sar_path, 'rb') as f:
                                file_bytes = f.read()
                            
                            sar_batch, sar_image = load_sar_image(io.BytesIO(file_bytes))
                            
                            if sar_batch is not None:
                                # Process with models
                                seg_mask, colorized = process_image(
                                    sar_batch,
                                    st.session_state['unet_model'],
                                    st.session_state.get('generator_model')
                                )
                                
                                # Visualize results
                                sar_rgb, colored_pred, overlay, colorized_img = visualize_results(
                                    sar_image, seg_mask, colorized
                                )
                                
                                # Check if ground truth exists
                                has_gt = os.path.exists(opt_path)
                                
                                if has_gt:
                                    # Load ground truth
                                    try:
                                        # Try to open with rasterio
                                        with rasterio.open(opt_path) as src:
                                            gt_image = src.read()
                                            
                                            if gt_image.shape[0] == 3:  # RGB image
                                                gt_image = np.transpose(gt_image, (1, 2, 0))
                                            else:  # Single band
                                                gt_image = src.read(1)
                                                
                                                # Convert to RGB for display
                                                # Convert to RGB for display
                                                gt_image = np.expand_dims(gt_image, axis=-1)
                                                gt_image = np.repeat(gt_image, 3, axis=-1)
                                    except Exception as rasterio_error:
                                        try:
                                            # If rasterio fails, try PIL
                                            gt_image = np.array(Image.open(opt_path).convert('RGB'))
                                        except Exception as pil_error:
                                            st.error(f"Both rasterio and PIL failed to load the ground truth: {str(pil_error)}")
                                            raise

                                    # Resize if needed
                                    if gt_image.shape[:2] != (256, 256):
                                        gt_image = cv2.resize(gt_image, (256, 256))

                                    # Normalize if needed - make sure values are in 0-255 range for display
                                    if gt_image.dtype != np.uint8:
                                        if np.max(gt_image) > 1.0 and np.max(gt_image) <= 255:
                                            gt_image = gt_image.astype(np.uint8)
                                        elif np.max(gt_image) <= 1.0:
                                            gt_image = (gt_image * 255).astype(np.uint8)
                                        else:
                                            # Scale to 0-255
                                            gt_min, gt_max = np.min(gt_image), np.max(gt_image)
                                            gt_image = ((gt_image - gt_min) / (gt_max - gt_min) * 255).astype(np.uint8)
                                    
                                    # Create 4-panel visualization with ground truth
                                    fig, axes = plt.subplots(1, 4, figsize=(16, 4))
                                    
                                    # Original SAR
                                    axes[0].imshow(sar_rgb, cmap='gray')
                                    axes[0].set_title('Original SAR', color='white')
                                    axes[0].axis('off')
                                    
                                    # Ground Truth
                                    axes[1].imshow(gt_image)
                                    axes[1].set_title('Ground Truth', color='white')
                                    axes[1].axis('off')
                                    
                                    # Segmentation
                                    axes[2].imshow(colored_pred)
                                    axes[2].set_title('Segmentation', color='white')
                                    axes[2].axis('off')
                                    
                                    # Generated Image
                                    if colorized_img is not None:
                                        # Convert from -1,1 to 0,1 range
                                        colorized_display = (colorized_img * 0.5) + 0.5
                                        axes[3].imshow(colorized_display)
                                    else:
                                        axes[3].imshow(overlay)
                                    axes[3].set_title('Generated Image', color='white')
                                    axes[3].axis('off')
                                    
                                    # Set dark background
                                    fig.patch.set_facecolor('#0a0a1f')
                                    for ax in axes:
                                        ax.set_facecolor('#0a0a1f')
                                    
                                    plt.tight_layout()
                                    
                                    # Display the figure
                                    st.pyplot(fig)
                                    
                                    # Calculate metrics if colorized image is available
                                    if colorized_img is not None:
                                        # Normalize both images to 0-1 range for comparison
                                        colorized_norm = (colorized_img * 0.5) + 0.5
                                        gt_norm = gt_image.astype(np.float32) / 255.0
                                        
                                        # Calculate PSNR
                                        mse = np.mean((colorized_norm - gt_norm) ** 2)
                                        psnr = 20 * np.log10(1.0 / np.sqrt(mse))
                                        
                                        # Calculate SSIM
                                        from skimage.metrics import structural_similarity as ssim

                                        try:
                                            # Check image dimensions and set appropriate window size
                                            min_dim = min(colorized_norm.shape[0], colorized_norm.shape[1])
                                            win_size = min(7, min_dim - (min_dim % 2) + 1)  # Ensure it's odd and smaller than min dimension
                                            
                                            ssim_value = ssim(
                                                colorized_norm, 
                                                gt_norm, 
                                                win_size=win_size,  # Explicitly set window size
                                                channel_axis=2,     # Specify channel axis for RGB images
                                                data_range=1.0
                                            )
                                        except Exception as e:
                                            st.warning(f"Could not calculate SSIM: {str(e)}")
                                            ssim_value = 0.0  # Default value if calculation fails
                                        
                                        # Display metrics
                                        col1, col2 = st.columns(2)
                                        with col1:
                                            st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                                            st.markdown(f"<p class='metric-value'>{psnr:.2f}</p>", unsafe_allow_html=True)
                                            st.markdown("<p class='metric-label'>PSNR (dB)</p>", unsafe_allow_html=True)
                                            st.markdown("</div>", unsafe_allow_html=True)
                                        
                                        with col2:
                                            st.markdown("<div class='metric-card'>", unsafe_allow_html=True)
                                            st.markdown(f"<p class='metric-value'>{ssim_value:.4f}</p>", unsafe_allow_html=True)
                                            st.markdown("<p class='metric-label'>SSIM</p>", unsafe_allow_html=True)
                                            st.markdown("</div>", unsafe_allow_html=True)
                                else:
                                    # Regular 3-panel visualization without ground truth
                                    col1, col2, col3 = st.columns(3)
                                    
                                    with col1:
                                        st.subheader("Original SAR Image")
                                        st.image(sar_rgb, use_container_width=True)
                                    
                                    with col2:
                                        st.subheader("Predicted Segmentation")
                                        st.image(colored_pred, use_container_width=True)
                                    
                                    with col3:
                                        st.subheader("Colorized SAR")
                                        if colorized_img is not None:
                                            # Convert from -1,1 to 0,1 range
                                            colorized_display = (colorized_img * 0.5) + 0.5
                                            st.image(colorized_display, use_container_width=True)
                                        else:
                                            st.image(overlay, use_container_width=True)
                                
                                # Add download buttons
                                col1, col2 = st.columns(2)
                                
                                with col1:
                                    # Save segmentation image
                                    seg_buf = io.BytesIO()
                                    plt.imsave(seg_buf, colored_pred, format='png')
                                    seg_buf.seek(0)
                                    
                                    st.download_button(
                                        label="Download Segmentation",
                                        data=seg_buf,
                                        file_name=f"sample_segmentation_{selected_sample}.png",
                                        mime="image/png",
                                        key="download_sample_seg"
                                    )
                                
                                with col2:
                                    # Save generated image
                                    gen_buf = io.BytesIO()
                                    if colorized_img is not None:
                                        plt.imsave(gen_buf, (colorized_img * 0.5) + 0.5, format='png')
                                    else:
                                        plt.imsave(gen_buf, overlay, format='png')
                                    gen_buf.seek(0)
                                    
                                    st.download_button(
                                        label="Download Optical-like Image",
                                        data=gen_buf,
                                        file_name=f"sample_optical_{selected_sample}.png",
                                        mime="image/png",
                                        key="download_sample_optical"
                                    )
                        except Exception as e:
                            st.error(f"Error processing sample image: {str(e)}")
            elif not sample_files:
                st.info("No sample images found. Please add some images to the 'samples/SAR' directory.")
            else:
                st.warning("Please load the models from the sidebar first.")
            


    # Close the card container
    st.markdown("</div>", unsafe_allow_html=True)

# Footer
st.markdown("""
<div style="text-align: center; margin-top: 2rem; padding: 1rem; background-color: rgba(0, 0, 0, 0.3); border-radius: 0.5rem;">
    <p style="color: #bfdbfe; font-size: 0.9rem;">
        SAR IMAGE PROCESSING | VARUN & MOKSHYAGNA
    </p>
</div>
""", unsafe_allow_html=True)
# ==================== UTILITY FUNCTIONS ====================

def create_stars_html():
    """Create twinkling stars effect for background"""
    stars_html = """
    <div class="stars">
    """
    for i in range(100):
        size = random.uniform(1, 3)
        top = random.uniform(0, 100)
        left = random.uniform(0, 100)
        duration = random.uniform(3, 8)
        opacity = random.uniform(0.2, 0.8)
        
        stars_html += f"""
        <div class="star" style="
            width: {size}px;
            height: {size}px;
            top: {top}%;
            left: {left}%;
            --duration: {duration}s;
            --opacity: {opacity};
        "></div>
        """
    stars_html += "</div>"
    return stars_html

# This function is called at the beginning of the app to set up the page
# Update the setup_page_style function to support both themes
def setup_page_style():
    """Set up the page style with CSS based on selected theme"""
    
    # Common CSS for both themes
    common_css = """
    /* Create twinkling stars effect */
    @keyframes twinkle {
        0%, 100% { opacity: 0.2; }
        50% { opacity: 1; }
    }
    
    .stars {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        pointer-events: none;
        z-index: -1;
    }
    
    .star {
        position: absolute;
        background-color: white;
        border-radius: 50%;
        animation: twinkle var(--duration) infinite;
        opacity: var(--opacity);
    }
    
    /* Tab styling */
    .stTabs [data-baseweb="tab-list"] {
        gap: 24px !important;
        border-radius: 0.5rem;
        padding: 0.8rem;
        margin-bottom: 3rem !important;
        display: flex;
        justify-content: center !important;
        width: 100%;
    }

    .stTabs [data-baseweb="tab"] {
        height: 5rem !important;
        white-space: pre-wrap;
        border-radius: 0.5rem;
        font-weight: 600 !important;
        font-size: 1.6rem !important;
        padding: 0 25px !important;
        display: flex;
        align-items: center;
        justify-content: center;
        min-width: 200px !important;
    }
    
    /* Add more space between tab panels */
    .stTabs [data-baseweb="tab-panel"] {
        padding-top: 3rem !important;
        padding-bottom: 3rem !important;
    }
    
    /* Button styling */
    .stButton>button {
        border: none;
        border-radius: 0.5rem;
        padding: 0.8rem 1.5rem !important;
        font-weight: 500;
        font-size: 1.2rem !important;
        margin-top: 1.5rem !important;
        margin-bottom: 1.5rem !important;
    }
    
    /* Spacing */
    .element-container {
        margin-bottom: 2.5rem !important;
    }
    
    h3 {
        margin-top: 3rem !important;
        margin-bottom: 2rem !important;
        font-size: 1.8rem !important;
    }
    
    h4 {
        margin-top: 2.5rem !important;
        margin-bottom: 1.5rem !important;
        font-size: 1.5rem !important;
    }
    
    h5 {
        margin-top: 2rem !important;
        margin-bottom: 1.5rem !important;
        font-size: 1.3rem !important;
    }
    
    img {
        margin-top: 1.5rem !important;
        margin-bottom: 2.5rem !important;
    }
    
    .stProgress > div {
        margin-top: 2rem !important;
        margin-bottom: 2rem !important;
    }
    
    .stSlider {
        padding-top: 1.5rem !important;
        padding-bottom: 2.5rem !important;
    }
    
    .row-widget {
        margin-top: 1.5rem !important;
        margin-bottom: 2.5rem !important;
    }
    """
    
    # Dark theme CSS
    dark_css = """
    .stApp {
        background-color: #0a0a1f;
        color: white;
    }
    
    .main {
        background-image: url("https://images.unsplash.com/photo-1451187580459-43490279c0fa?ixlib=rb-1.2.1&auto=format&fit=crop&w=1352&q=80");
        background-size: cover;
        background-position: center;
        background-repeat: no-repeat;
        background-attachment: fixed;
        position: relative;
    }
    
    .main::before {
        content: "";
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background-color: rgba(10, 10, 31, 0.7);
        backdrop-filter: blur(5px);
        z-index: -1;
    }
    
    /* Title styling */
    h1.title {
        background: linear-gradient(to right, #a78bfa, #ec4899, #3b82f6);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
        color: transparent;
        font-size: 3rem !important;
        font-weight: bold !important;
        text-align: center !important;
        margin-bottom: 0.5rem !important;
        display: block !important;
        position: relative !important;
        z-index: 10 !important;
    }
    
    p.subtitle {
        color: #bfdbfe !important;
        font-size: 1.2rem !important;
        text-align: center !important;
        margin-bottom: 2rem !important;
        position: relative !important;
        z-index: 10 !important;
    }
    
    /* Tab styling */
    .stTabs [data-baseweb="tab-list"] {
        background-color: rgba(0, 0, 0, 0.3);
    }
    
    .stTabs [data-baseweb="tab"] {
        background-color: transparent;
        color: white;
    }
    
    .stTabs [aria-selected="true"] {
        background-color: rgba(147, 51, 234, 0.5) !important;
        transform: scale(1.05);
        transition: all 0.2s ease;
    }
    
    /* Card and box styling */
    .upload-box {
        border: 2px dashed rgba(147, 51, 234, 0.5);
        border-radius: 1rem;
        padding: 4rem !important;
        text-align: center;
        margin-bottom: 3rem !important;
    }
    
    .card {
        background-color: rgba(0, 0, 0, 0.3);
        border: 1px solid rgba(147, 51, 234, 0.3);
        border-radius: 1rem;
        padding: 2.5rem !important;
        backdrop-filter: blur(10px);
        margin-bottom: 3rem !important;
    }
    
    /* Button styling */
    .stButton>button {
        background: linear-gradient(to right, #7c3aed, #2563eb);
        color: white;
    }
    
    .stButton>button:hover {
        background: linear-gradient(to right, #6d28d9, #1d4ed8);
    }
    
    .download-btn {
        background-color: #2563eb !important;
    }
    
    .stSlider>div>div>div {
        background-color: #7c3aed;
    }
    
    /* Metrics styling */
    .plot-container {
        background-color: rgba(0, 0, 0, 0.3);
        border-radius: 1rem;
        padding: 2rem !important;
        margin-bottom: 3rem !important;
    }
    
    .metric-card {
        background-color: rgba(0, 0, 0, 0.3);
        border: 1px solid rgba(147, 51, 234, 0.3);
        border-radius: 0.5rem;
        padding: 1.5rem !important;
        text-align: center;
        margin-bottom: 2rem !important;
    }
    
    .metric-value {
        font-size: 2rem !important;
        font-weight: bold;
        color: #a78bfa;
    }
    
    .metric-label {
        font-size: 1.1rem !important;
        color: #bfdbfe;
    }
    
    /* Form elements */
    .stFileUploader > div {
        background-color: rgba(0, 0, 0, 0.3) !important;
        border: 1px dashed rgba(147, 51, 234, 0.5) !important;
        padding: 2rem !important;
        margin-bottom: 2rem !important;
    }
    
    .stSelectbox > div > div {
        background-color: rgba(0, 0, 0, 0.3) !important;
        border: 1px solid rgba(147, 51, 234, 0.3) !important;
    }
    """
    
    # Light theme CSS
    # Light theme CSS - simplified with cream/whitish background and no background image
    # Light theme CSS - keeps dark background but uses light text
    light_css = """
        /* Keep the same dark background */
        .stApp {
            background-color: #0a0a1f;
        }
        
        .main {
            background-image: url("https://images.unsplash.com/photo-1451187580459-43490279c0fa?ixlib=rb-1.2.1&auto=format&fit=crop&w=1352&q=80");
            background-size: cover;
            background-position: center;
            background-repeat: no-repeat;
            background-attachment: fixed;
            position: relative;
        }
        
        .main::before {
            content: "";
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: rgba(10, 10, 31, 0.7);
            backdrop-filter: blur(5px);
            z-index: -1;
        }
        
        /* Make all text white/light */
        p, span, label, div, h1, h2, h3, h4, h5, h6, li {
            color: white !important;
        }
        
        /* Title styling - brighter gradient for better visibility */
        h1.title {
            background: linear-gradient(to right, #d8b4fe, #f9a8d4, #93c5fd);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            color: transparent;
            font-size: 3rem !important;
            font-weight: bold !important;
            text-align: center !important;
            margin-bottom: 0.5rem !important;
            display: block !important;
            position: relative !important;
            z-index: 10 !important;
        }
        
        p.subtitle {
            color: #e0e7ff !important; /* Lighter purple */
            font-size: 1.2rem !important;
            text-align: center !important;
            margin-bottom: 2rem !important;
            position: relative !important;
            z-index: 10 !important;
        }
        
        /* Tab styling - brighter for better visibility */
        .stTabs [data-baseweb="tab-list"] {
            background-color: rgba(0, 0, 0, 0.3);
        }
        
        .stTabs [data-baseweb="tab"] {
            background-color: transparent;
            color: white !important;
        }
        
        .stTabs [aria-selected="true"] {
            background-color: rgba(167, 139, 250, 0.5) !important; /* Brighter purple */
            transform: scale(1.05);
            transition: all 0.2s ease;
        }
        
        /* Card and box styling - brighter borders */
        .upload-box {
            border: 2px dashed rgba(167, 139, 250, 0.7); /* Brighter purple */
            border-radius: 1rem;
            padding: 4rem !important;
            text-align: center;
            margin-bottom: 3rem !important;
        }
        
        .card {
            background-color: rgba(0, 0, 0, 0.3);
            border: 1px solid rgba(167, 139, 250, 0.5); /* Brighter purple */
            border-radius: 1rem;
            padding: 2.5rem !important;
            backdrop-filter: blur(10px);
            margin-bottom: 3rem !important;
        }
        
        /* Button styling - brighter gradient */
        .stButton>button {
            background: linear-gradient(to right, #a78bfa, #60a5fa);
            color: white;
        }
        
        .stButton>button:hover {
            background: linear-gradient(to right, #8b5cf6, #3b82f6);
        }
        
        .download-btn {
            background-color: #60a5fa !important;
        }
        
        .stSlider>div>div>div {
            background-color: #a78bfa;
        }
        
        /* Metrics styling - brighter accents */
        .plot-container {
            background-color: rgba(0, 0, 0, 0.3);
            border-radius: 1rem;
            padding: 2rem !important;
            margin-bottom: 3rem !important;
        }
        
        .metric-card {
            background-color: rgba(0, 0, 0, 0.3);
            border: 1px solid rgba(167, 139, 250, 0.5); /* Brighter purple */
            border-radius: 0.5rem;
            padding: 1.5rem !important;
            text-align: center;
            margin-bottom: 2rem !important;
        }
        
        .metric-value {
            font-size: 2rem !important;
            font-weight: bold;
            color: #d8b4fe; /* Brighter purple */
        }
        
        .metric-label {
            font-size: 1.1rem !important;
            color: #e0e7ff; /* Lighter purple */
        }
        
        /* Form elements - brighter borders */
        .stFileUploader > div {
            background-color: rgba(0, 0, 0, 0.3) !important;
            border: 1px dashed rgba(167, 139, 250, 0.7) !important; /* Brighter purple */
            padding: 2rem !important;
            margin-bottom: 2rem !important;
        }
        
        .stSelectbox > div > div {
            background-color: rgba(0, 0, 0, 0.3) !important;
            border: 1px solid rgba(167, 139, 250, 0.5) !important; /* Brighter purple */
        }
        
        /* Make sure all text inputs have white text */
        input, textarea {
            color: white !important;
        }
        
        /* Ensure sidebar text is white */
        .css-1d391kg, .css-1lcbmhc {
            color: white !important;
        }
        
        /* Make sure plot text is visible on dark background */
        .js-plotly-plot .plotly .main-svg text {
            fill: white !important;
        }
        
        /* Keep stars visible in light theme */
        .star {
            background-color: white;
            opacity: 0.8;
        }
        
        /* Make sure all streamlit elements have white text */
        .stMarkdown, .stText, .stCode, .stTextInput, .stTextArea, .stSelectbox, .stMultiselect, 
        .stSlider, .stCheckbox, .stRadio, .stNumber, .stDate, .stTime, .stDateInput, .stTimeInput {
            color: white !important;
        }
        
        /* Ensure dropdown options are visible */
        .stSelectbox ul li {
            color: black !important;
        }
        """

    
    # Apply the appropriate CSS based on the selected theme
    # Apply the appropriate CSS based on the selected theme
    if st.session_state.theme == "dark":
        st.markdown(f"<style>{common_css}{dark_css}</style>", unsafe_allow_html=True)
    else:
        st.markdown(f"<style>{common_css}{light_css}</style>", unsafe_allow_html=True)

# ==================== MAIN EXECUTION ====================

if __name__ == "__main__":
    # Set up page style
    setup_page_style()
    
    # Initialize GPU if available
    setup_gpu()
    
    # Initialize session state variables
    if 'app_mode' not in st.session_state:
        st.session_state.app_mode = "SAR Colorization"
    if 'model_loaded' not in st.session_state:
        st.session_state.model_loaded = False
    if 'segmentation' not in st.session_state:
        st.session_state.segmentation = SARSegmentation(img_rows=256, img_cols=256)
    if 'processed_images' not in st.session_state:
        st.session_state.processed_images = []