from flask import Flask, request, jsonify
from pytubefix import YouTube
import re

app = Flask(__name__)

def download_video(url, resolution):
    try:
        yt = YouTube(url, use_po_token=True)
        stream = yt.streams.filter(progressive=True, file_extension='mp4', resolution=resolution).first()
        if stream:
            stream.download()
            return True, None
        else:
            return False, f"{resolution}のストリームが見つかりませんでした。利用可能: {[s.resolution for s in yt.streams.filter(progressive=True, file_extension='mp4')]}"
    except Exception as e:
        print(f"[Download Error] {e}")  # ← ここでログを確認
        return False, str(e)


def get_video_info(url):
    try:
        yt = YouTube(url, use_po_token=True)
        video_info = {
            "title": yt.title,
            "author": yt.author,
            "length": yt.length,
            "views": yt.views,
            "description": yt.description,
            "publish_date": yt.publish_date.isoformat() if yt.publish_date else None
        }
        return video_info, None
    except Exception as e:
        print(f"[Video Info Error] {e}")
        return None, str(e)


def is_valid_youtube_url(url):
    pattern = r"^(https?://)?(www\.)?(youtube\.com/watch\?v=|youtu\.be/)[\w-]+(&\S*)?$"
    return re.match(pattern, url) is not None

@app.route('/download', methods=['GET'])
def download_by_resolution():
    url = request.args.get('url')
    resolution = request.args.get('resolution', '720p')

    if not url:
        return jsonify({"error": "'url' パラメーターが必要です。"}), 400

    if not is_valid_youtube_url(url):
        return jsonify({"error": "無効なYouTube URLです。"}), 400

    success, error_message = download_video(url, resolution)

    if success:
        return jsonify({"message": f"{resolution}の動画を正常にダウンロードしました。"}), 200
    else:
        return jsonify({"error": error_message}), 500

@app.route('/video_info', methods=['GET'])
def video_info():
    url = request.args.get('url')

    if not url:
        return jsonify({"error": "'url' パラメーターが必要です。"}), 400

    if not is_valid_youtube_url(url):
        return jsonify({"error": "無効なYouTube URLです。"}), 400

    info, error_message = get_video_info(url)

    if info:
        return jsonify(info), 200
    else:
        return jsonify({"error": error_message}), 500

if __name__ == '__main__':
    app.run(debug=True, host="0.0.0.0", port=7860)