#!/usr/bin/env python

from __future__ import annotations

import argparse
import functools
import os
import pathlib
import sys
import tarfile
import urllib
from typing import Callable

sys.path.insert(0, 'anime_face_landmark_detection')

import cv2
import gradio as gr
import huggingface_hub
import numpy as np
import PIL.Image
import torch
import torchvision.transforms as T
from CFA import CFA

TOKEN = os.environ['TOKEN']

MODEL_REPO = 'hysts/anime_face_landmark_detection'
MODEL_FILENAME = 'checkpoint_landmark_191116.pth'

NUM_LANDMARK = 24
CROP_SIZE = 128


def parse_args() -> argparse.Namespace:
    parser = argparse.ArgumentParser()
    parser.add_argument('--device', type=str, default='cpu')
    parser.add_argument('--theme', type=str)
    parser.add_argument('--live', action='store_true')
    parser.add_argument('--share', action='store_true')
    parser.add_argument('--port', type=int)
    parser.add_argument('--disable-queue',
                        dest='enable_queue',
                        action='store_false')
    parser.add_argument('--allow-flagging', type=str, default='never')
    parser.add_argument('--allow-screenshot', action='store_true')
    return parser.parse_args()


def load_sample_image_paths() -> list[pathlib.Path]:
    image_dir = pathlib.Path('images')
    if not image_dir.exists():
        dataset_repo = 'hysts/sample-images-TADNE'
        path = huggingface_hub.hf_hub_download(dataset_repo,
                                               'images.tar.gz',
                                               repo_type='dataset',
                                               use_auth_token=TOKEN)
        with tarfile.open(path) as f:
            f.extractall()
    return sorted(image_dir.glob('*'))


def load_face_detector() -> cv2.CascadeClassifier:
    url = 'https://raw.githubusercontent.com/nagadomi/lbpcascade_animeface/master/lbpcascade_animeface.xml'
    path = pathlib.Path('lbpcascade_animeface.xml')
    if not path.exists():
        urllib.request.urlretrieve(url, path.as_posix())
    return cv2.CascadeClassifier(path.as_posix())


def load_landmark_detector(device: torch.device) -> torch.nn.Module:
    path = huggingface_hub.hf_hub_download(MODEL_REPO,
                                           MODEL_FILENAME,
                                           use_auth_token=TOKEN)
    model = CFA(output_channel_num=NUM_LANDMARK + 1, checkpoint_name=path)
    model.to(device)
    model.eval()
    return model


@torch.inference_mode()
def detect(image, face_detector: cv2.CascadeClassifier, device: torch.device,
           transform: Callable,
           landmark_detector: torch.nn.Module) -> np.ndarray:
    image = cv2.imread(image.name)
    gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
    preds = face_detector.detectMultiScale(gray,
                                           scaleFactor=1.1,
                                           minNeighbors=5,
                                           minSize=(24, 24))

    image_h, image_w = image.shape[:2]
    pil_image = PIL.Image.fromarray(image[:, :, ::-1].copy())

    res = image.copy()
    for x_orig, y_orig, w_orig, h_orig in preds:

        x0 = round(max(x_orig - w_orig / 8, 0))
        x1 = round(min(x_orig + w_orig * 9 / 8, image_w))
        y0 = round(max(y_orig - h_orig / 4, 0))
        y1 = y_orig + h_orig
        w = x1 - x0
        h = y1 - y0

        temp = pil_image.crop((x0, y0, x1, y1))
        temp = temp.resize((CROP_SIZE, CROP_SIZE), PIL.Image.BICUBIC)
        data = transform(temp)
        data = data.to(device).unsqueeze(0)

        heatmaps = landmark_detector(data)
        heatmaps = heatmaps[-1].cpu().numpy()[0]

        cv2.rectangle(res, (x0, y0), (x1, y1), (0, 255, 0), 2)

        for i in range(NUM_LANDMARK):
            heatmap = cv2.resize(heatmaps[i], (CROP_SIZE, CROP_SIZE),
                                 interpolation=cv2.INTER_CUBIC)
            pty, ptx = np.unravel_index(np.argmax(heatmap), heatmap.shape)
            pt_crop = np.round(np.array([ptx * w, pty * h]) /
                               CROP_SIZE).astype(int)
            pt = np.array([x0, y0]) + pt_crop
            cv2.circle(res, tuple(pt), 2, (0, 0, 255), cv2.FILLED)

    res = cv2.cvtColor(res, cv2.COLOR_BGR2RGB)
    return res


def main():
    gr.close_all()

    args = parse_args()
    device = torch.device(args.device)

    image_paths = load_sample_image_paths()
    examples = [[path.as_posix()] for path in image_paths]

    face_detector = load_face_detector()
    landmark_detector = load_landmark_detector(device)
    transform = T.Compose([
        T.ToTensor(),
        T.Normalize(mean=[0.5, 0.5, 0.5], std=[0.5, 0.5, 0.5]),
    ])

    func = functools.partial(detect,
                             face_detector=face_detector,
                             device=device,
                             transform=transform,
                             landmark_detector=landmark_detector)
    func = functools.update_wrapper(func, detect)

    repo_url = 'https://github.com/kanosawa/anime_face_landmark_detection'
    title = 'kanosawa/anime_face_landmark_detection'
    description = f'A demo for {repo_url}'
    article = None

    gr.Interface(
        func,
        gr.inputs.Image(type='file', label='Input'),
        gr.outputs.Image(label='Output'),
        theme=args.theme,
        title=title,
        description=description,
        article=article,
        examples=examples,
        allow_screenshot=args.allow_screenshot,
        allow_flagging=args.allow_flagging,
        live=args.live,
    ).launch(
        enable_queue=args.enable_queue,
        server_port=args.port,
        share=args.share,
    )


if __name__ == '__main__':
    main()