import shutil
from pathlib import Path
from typing import List, Dict, Union, Tuple, Literal, Optional

import numpy as np
import gradio as gr
from gradio.components.base import Component
from ultralytics import YOLO

from utils import download_model, detect_image, detect_video, get_csv_annotate


# ======================= МОДЕЛЬ ===================================

MODELS_DIR = Path('models')
MODELS_DIR.mkdir(exist_ok=True)

MODELS = {
    'yolov8n.pt': 'https://github.com/ultralytics/assets/releases/download/v8.1.0/yolov8n.pt',
    'yolov8s.pt': 'https://github.com/ultralytics/assets/releases/download/v8.1.0/yolov8s.pt',
    'yolov8m.pt': 'https://github.com/ultralytics/assets/releases/download/v8.1.0/yolov8m.pt',
    'yolov8l.pt': 'https://github.com/ultralytics/assets/releases/download/v8.1.0/yolov8l.pt',
    'yolov8x.pt': 'https://github.com/ultralytics/assets/releases/download/v8.1.0/yolov8x.pt',
}
MODEL_NAMES = list(MODELS.keys())

model_path = download_model(MODEL_NAMES[0], MODELS_DIR, MODELS)
default_model = YOLO(model_path)

IMAGE_EXTENSIONS = ['.jpg', '.jpeg', '.png']
VIDEO_EXTENSIONS = ['.mp4', '.avi']


# =================== ДОП ФУНКЦИИ ИНТРЕФЕЙСА ==============================

def change_model(model_state: Dict[str, YOLO], model_name: str):
    progress = gr.Progress()
    progress(0.3, desc='Загрузка модели')
    model_path = download_model(model_name)
    progress(0.7, desc='Инициализация модели')
    model_state['model'] = YOLO(model_path)
    return f"Модель {model_name} инициализирована"


def detect(file_path: str, file_link: str, model_state: Dict[str, YOLO], conf: float, iou: float):
    model = model_state['model']
    if file_link:
        file_path = file_link

    file_ext = f'.{file_path.rsplit(".")[-1]}'
    if file_ext in IMAGE_EXTENSIONS:
        np_image = detect_image(file_path, model, conf, iou)
        return np_image, "Детекция завершена, открытие изображения..."
    elif file_ext in VIDEO_EXTENSIONS or 'youtube.com' in file_link:
        video_path = detect_video(file_path, model, conf, iou)
        return video_path, "Детекция завершена, конвертация и открытие видео..."
    else:
        gr.Info('Неверный формат изображения или видео...')
        return None, None

# =================== КОМПОНЕНТЫ ИНТРЕФЕЙСА ==============================

def get_output_media_components(detect_result: Optional[Union[np.ndarray, str, Path]] = None):
    visible = isinstance(detect_result, np.ndarray)
    image_output = gr.Image(
        value=detect_result if visible else None,
        type="numpy",
        width=640,
        height=480,
        visible=visible,
        label='Output',
        )
    visible = isinstance(detect_result, (str, Path))
    video_output = gr.Video(
        value=detect_result if visible else None,
        width=640,
        height=480,
        visible=visible,
        label='Output',
        )
    clear_btn = gr.Button(
        value='Clear',
        scale=0,
        visible=detect_result is not None,
        )
    return image_output, video_output, clear_btn


def get_download_csv_btn(csv_annotations_path: Optional[Path] = None):
    download_csv_btn = gr.DownloadButton(
        label='Скачать csv аннотации к видео',
        value=csv_annotations_path,
        scale=0,
        visible=csv_annotations_path is not None,
        )
    return download_csv_btn

# =================== ИНТЕРФЕЙС ПРИЛОЖЕНИЯ ==========================

css = '''
.gradio-container { width: 70% !important }
'''
with gr.Blocks(css=css) as demo:
    gr.HTML("""<h3 style='text-align: center'>YOLOv8 Detector</h3>""")
    
    model_state = gr.State({'model': default_model})
    detect_result = gr.State(None)
    csv_annotations_path = gr.State(None)

    with gr.Row():
        with gr.Column():
            file_path = gr.File(file_types=['image', 'video'], file_count='single', label='Выберите изображение или видео')
            file_link = gr.Textbox(label='Прямая ссылка на изображение или ссылка на YouTube')
            model_name = gr.Radio(choices=MODEL_NAMES, value=MODEL_NAMES[0], label='Модель YOLO')
            conf = gr.Slider(0, 1, value=0.5, step=0.05, label='Порог уверенности')
            iou = gr.Slider(0, 1, value=0.7, step=0.1, label='Порог IOU')
            status_message = gr.Textbox(value='Готово к работе', label='Статус')
            detect_btn = gr.Button('Detect', interactive=True)

        with gr.Column():
            image_output, video_output, clear_btn = get_output_media_components()
            download_csv_btn = get_download_csv_btn()

    model_name.change(
        fn=lambda: gr.update(interactive=False),
        inputs=None,
        outputs=[detect_btn],
    ).then(
        fn=change_model,
        inputs=[model_state, model_name],
        outputs=[status_message],
    ).success(
        fn=lambda: gr.update(interactive=True),
        inputs=None,
        outputs=[detect_btn],
    )

    detect_btn.click(
        fn=detect,
        inputs=[file_path, file_link, model_state, conf, iou],
        outputs=[detect_result, status_message],
    ).success(
        fn=get_output_media_components,
        inputs=[detect_result],
        outputs=[image_output, video_output, clear_btn],
    ).then(
        fn=lambda: 'Готово к работе',
        inputs=None,
        outputs=[status_message],
    ).then(
        fn=get_csv_annotate,
        inputs=[detect_result],
        outputs=[csv_annotations_path],
    ).success(
        fn=get_download_csv_btn,
        inputs=[csv_annotations_path],
        outputs=[download_csv_btn],
    )

    def clear_results_dir(detect_result):
        if isinstance(detect_result, Path):
            shutil.rmtree(detect_result.parent, ignore_errors=True)

    clear_components = [image_output, video_output, clear_btn, download_csv_btn]
    clear_btn.click(
        fn=lambda: [gr.update(visible=False) for _ in range(len(clear_components))],
        inputs=None,
        outputs=clear_components,
    ).then(
        fn=clear_results_dir,
        inputs=[detect_result],
        outputs=None,
    ).then(
        fn=lambda: (None, None),
        inputs=None,
        outputs=[detect_result, csv_annotations_path]
        )

    gr.HTML("""<h3 style='text-align: center'>
    <a href="https://github.com/sergey21000/yolo-detector" target='_blank'>GitHub Page</a></h3>
    """)
    
demo.launch(server_name='0.0.0.0')  # debug=True