import cv2
import yt_dlp
import numpy as np
import json
import time
import base64

_snapshot_cache = {}
CACHE_TTL = 10

def capture_stream_snapshot(youtube_url, output_file="snapshot.jpg", toBuffer=False):
    # 1. Configure yt-dlp to get the direct stream URL
    ydl_opts = {
        "format": "best",
        "quiet": True,
        "no_warnings": True,
    }

    with yt_dlp.YoutubeDL(ydl_opts) as ydl:
        try:
            info = ydl.extract_info(youtube_url, download=False)
            stream_url = info["url"]
        except Exception as e:
            print(f"Error extracting info: {e}")
            return None

    # 2. Use OpenCV to capture a frame from the stream URL
    try:
        cap = cv2.VideoCapture(stream_url)
    except Exception as e:
        print(f"Error opening VideoCapture: {e}")
        return None

    if not cap.isOpened():
        print("Error: Could not open video stream.")
        return None

    # Read a single frame
    success, frame = cap.read()

    if success:
        if toBuffer:
            # Encode frame as JPEG to memory buffer
            ret, buf = cv2.imencode(".jpg", frame)
            if ret:
                cap.release()
                return buf.tobytes()
            else:
                cap.release()
                return None
        else:
            # 3. Save the frame as an image
            cv2.imwrite(output_file, frame)
            cap.release()
            return True
    else:
        print("Error: Could not read frame from stream.")
        cap.release()
        return None


# Shsf Handler
def main(args):
    route = args.get("route", "")
    
    # Handle /app/{id}.jpg
    if route.startswith("app/") and route.endswith(".jpg"):
        url_id = route.split("/")[-1].replace(".jpg", "")
        now = time.time()
        
        if url_id in _snapshot_cache:
            ts, encoded = _snapshot_cache[url_id]
            if now - ts < CACHE_TTL:
                return {
                    "_shsf": "v1", # Changed to v1 for simpler binary response if v2 is picky
                    "_code": 200,
                    "_res": encoded,
                    "_is_base64": True,
                    "_headers": { "Content-Type": "image/jpeg", "X-Cache": "HIT" }
                }
        
        # Cache miss
        yt_url = f"https://www.youtube.com/watch?v={url_id}"
        image_bytes = capture_stream_snapshot(yt_url, toBuffer=True)
        if image_bytes:
            encoded_content = base64.b64encode(image_bytes).decode('utf-8')
            _snapshot_cache[url_id] = (now, encoded_content)
            return {
                "_shsf": "v1",
                "_code": 200,
                "_res": encoded_content,
                "_is_base64": True,
                "_headers": { "Content-Type": "image/jpeg", "X-Cache": "MISS" }
            }

    if route == "snapshot":
        url = args.get("body", "")
        try:
            url = json.loads(url)
        except json.JSONDecodeError:
            return {
                "_shsf": "v2",
                "_code": 400,
                "_res": {"message": "Invalid JSON input."},
                "_headers": { "Content-Type": "application/json" },
            }
        url = url.get("url", "")
        if not url:
            return {
                "_shsf": "v2",
                "_code": 400,
                "_res": {"message": "URL not provided."},
                "_headers": { "Content-Type": "application/json" },
            }
        
        try:
            image_bytes = capture_stream_snapshot(url, toBuffer=True)
            if image_bytes:
                encoded_content = base64.b64encode(image_bytes).decode('utf-8')
                return {
                    "_shsf": "v2",
                    "_code": 200,
                    "_res": { "message": "done", "buffer": encoded_content },
                    "_headers": { "Content-Type": "application/json" },
                }
        except Exception as e:
            return {
                "_shsf": "v2",
                "_code": 500,
                "_res": {"message": str(e)},
                "_headers": { "Content-Type": "application/json" },
            }
        
        return {
            "_shsf": "v2",
            "_code": 500,
            "_res": {"message": "Could not capture snapshot."},
            "_headers": { "Content-Type": "application/json" },
        }

    elif route == "health":
        return {
            "_shsf": "v2",
            "_code": 200,
            "_res": {"message": "Service is healthy."},
            "cache_size": len(_snapshot_cache),
            "_headers": { "Content-Type": "application/json" },
        }
    
    elif route == "default": # UI Route
        try:
            with open("/app/ui.html", "r") as f:
                content = f.read()
            return {
                "_shsf": "v2",
                "_code": 200,
                "_res": content,
                "_headers": { "Content-Type": "text/html" },
            }
        except Exception as e:
            return {
                "_shsf": "v2",
                "_code": 404,
                "_res": {"message": "UI file not found or error."},
            }
        
if __name__ == "__main__":
    print("running stream-shot")