#!/usr/bin/env python3
"""
Compatibility shim: CoreVideoProcessor

Bridges the legacy import `from processing.video.video_processor import CoreVideoProcessor`
to the modern pipeline functions living in `utils.cv_processing` and models in `core.models`.
"""

from __future__ import annotations

from dataclasses import dataclass
from typing import Optional, Dict, Any, Tuple, Callable

import cv2
import numpy as np
import time
import threading

from utils.logger import get_logger
from core.models import ModelManager

# ← these funcs are the ones you showed (in utils/cv_processing.py)
from utils.cv_processing import (
    segment_person_hq,
    refine_mask_hq,
    replace_background_hq,
    create_professional_background,
    validate_video_file,
)

@dataclass
class ProcessorConfig:
    background_preset: str = "minimalist"   # key in PROFESSIONAL_BACKGROUNDS
    write_fps: Optional[float] = None       # None -> keep source fps

class CoreVideoProcessor:
    """
    Minimal, safe implementation used by core/app.py.
    It relies on ModelManager (SAM2 + MatAnyone) and your cv_processing helpers.
    Now supports live progress + cancel/stop.
    """

    def __init__(self, config: Optional[ProcessorConfig] = None, models: Optional[ModelManager] = None):
        self.log = get_logger(f"{__name__}.CoreVideoProcessor")
        self.config = config or ProcessorConfig()
        self.models = models or ModelManager()
        try:
            self.models.load_all()
        except Exception as e:
            self.log.warning(f"Model load issue (will use fallbacks if needed): {e}")

    # --- single-frame API (useful for images or per-frame video loop) ---
    def process_frame(self, frame: np.ndarray, background: np.ndarray) -> Dict[str, Any]:
        """Return dict with composited frame + mask; always succeeds with fallbacks."""
        predictor = None
        try:
            sam2_model = self.models.get_sam2()
            if sam2_model is not None:
                if hasattr(sam2_model, 'predictor'):
                    predictor = sam2_model.predictor
                elif hasattr(sam2_model, 'set_image'):
                    predictor = sam2_model
                elif isinstance(sam2_model, dict) and 'model' in sam2_model:
                    self.log.warning("SAM2 loaded as dict format, not directly usable")
                    predictor = None
            if predictor is None:
                self.log.debug("SAM2 predictor not available, will use fallback")
        except Exception as e:
            self.log.warning(f"SAM2 predictor unavailable: {e}")

        # 1) segment
        mask = segment_person_hq(frame, predictor, fallback_enabled=True)

        # 2) refine
        matanyone = None
        try:
            matanyone_model = self.models.get_matanyone()
            if matanyone_model is not None:
                matanyone = matanyone_model
        except Exception as e:
            self.log.warning(f"MatAnyone unavailable: {e}")

        mask_refined = refine_mask_hq(frame, mask, matanyone, fallback_enabled=True)

        # 3) composite
        out = replace_background_hq(frame, mask_refined, background, fallback_enabled=True)

        return {"frame": out, "mask": mask_refined}

    # --- simple video API (covers typical usage in older core/app.py code) ---
    def process_video(
        self,
        input_path: str,
        output_path: str,
        bg_config: Optional[Dict[str, Any]] = None,
        progress_callback: Optional[Callable[[int, int, float], None]] = None,  # <-- ADDED
        stop_event: Optional[threading.Event] = None   # <-- ADDED
    ) -> Dict[str, Any]:
        """
        Process a full video with live progress and optional stop.
        progress_callback: function(current_frame, total_frames, fps)
        stop_event: threading.Event() - if set(), abort processing.
        Returns: dict with stats.
        """
        ok, msg = validate_video_file(input_path)
        if not ok:
            raise ValueError(f"Invalid video: {msg}")
        self.log.info(f"Video validation: {msg}")

        cap = cv2.VideoCapture(input_path)
        if not cap.isOpened():
            raise RuntimeError(f"Could not open video: {input_path}")

        width  = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
        height = int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))
        fps    = cap.get(cv2.CAP_PROP_FPS)
        total_frames = int(cap.get(cv2.CAP_PROP_FRAME_COUNT))
        fps_out = self.config.write_fps or (fps if fps and fps > 0 else 25.0)

        fourcc = cv2.VideoWriter_fourcc(*"mp4v")
        writer = cv2.VideoWriter(output_path, fourcc, fps_out, (width, height))

        # Build background (once)
        from utils.cv_processing import PROFESSIONAL_BACKGROUNDS
        preset = self.config.background_preset
        cfg = bg_config or PROFESSIONAL_BACKGROUNDS.get(preset, PROFESSIONAL_BACKGROUNDS["minimalist"])
        background = create_professional_background(cfg, width, height)

        frame_count = 0
        start_time = time.time()
        try:
            while True:
                ret, frame = cap.read()
                if not ret:
                    break

                # --- CANCEL SUPPORT ---
                if stop_event is not None and stop_event.is_set():
                    self.log.info("Processing stopped by user request")  # <-- CHANGED
                    break

                res = self.process_frame(frame, background)
                writer.write(res["frame"])
                frame_count += 1

                # --- LIVE PROGRESS ---
                if progress_callback:
                    elapsed = time.time() - start_time
                    fps_live = frame_count / elapsed if elapsed > 0 else 0
                    progress_callback(
                        frame_count,
                        total_frames,
                        fps_live
                    )
        finally:
            cap.release()
            writer.release()

        self.log.info(f"Processed {frame_count} frames → {output_path}")
        return {
            "frames": frame_count,
            "width": width,
            "height": height,
            "fps_out": fps_out
        }

# Backward-compat export name
VideoProcessor = CoreVideoProcessor