import logging
import shutil
import tempfile
import subprocess
from pathlib import Path
from moviepy.editor import VideoFileClip
import gradio as gr
import requests
from urllib.parse import urlparse

logging.basicConfig(level=logging.INFO)

def download_file(url, destination):
    """Downloads a file from a url to a destination."""
    response = requests.get(url)
    response.raise_for_status()
    with open(destination, 'wb') as f:
        f.write(response.content)

def get_input_path(video_file, video_url, temp_dir):
    """Returns the path to the video file, downloading it if necessary."""
    if video_file is not None:
        return Path(video_file.name)
    elif video_url:
        url_path = urlparse(video_url).path
        file_name = Path(url_path).name
        destination = temp_dir / file_name
        download_file(video_url, destination)
        return destination
    else:
        raise ValueError("No input was provided.")

def get_output_path(input_path, temp_dir, res):
    """Returns the path to the output file, creating it if necessary."""
    output_path = temp_dir / (Path(input_path).stem + f"_{res}.m3u8")
    return output_path

def get_aspect_ratio(input_path, aspect_ratio):
    """Returns the aspect ratio of the video, calculating it if necessary."""
    if aspect_ratio is not None:
        return aspect_ratio
    video = VideoFileClip(str(input_path))
    return f"{video.size[0]}:{video.size[1]}"

def create_master_playlist(output_paths, temp_dir):
    """Creates a master playlist .m3u8 file that includes all other .m3u8 files."""
    master_playlist_path = temp_dir / "master_playlist.m3u8"
    with open(master_playlist_path, 'w') as f:
        f.write("#EXTM3U\n")
        for path in output_paths:
            f.write(f"#EXT-X-STREAM-INF:BANDWIDTH={1000*1000},RESOLUTION={path.stem.split('_')[-1]}\n")
            f.write(f"{path.name}\n")
    return master_playlist_path

def convert_video(video_file, quality, aspect_ratio, video_url):
    standard_resolutions = [4320, 2160, 1440, 1080, 720, 480, 360, 240, 144]  # 8K, 4K, 2K, Full HD, HD, SD in pixels

    with tempfile.TemporaryDirectory() as temp_dir:
        temp_dir = Path(temp_dir)
        input_path = get_input_path(video_file, video_url, temp_dir)

        aspect_ratio = get_aspect_ratio(input_path, aspect_ratio)

        video = VideoFileClip(str(input_path))
        original_height = video.size[1]

        output_paths = []  # Define output_paths as an empty list

        for res in standard_resolutions:
            # Skip if resolution is higher than original
            if res > original_height:
                continue

            scale = "-1:" + str(res)  # we scale the height to res and keep aspect ratio
            output_path = get_output_path(input_path, temp_dir, str(res) + 'p')  # pass the resolution to create a unique output file

            ffmpeg_command = [
                "ffmpeg", "-i", str(input_path), "-c:v", "libx264", "-crf", str(quality),
                "-vf", f"scale={scale}:force_original_aspect_ratio=decrease,pad=ceil(iw/2)*2:ceil(ih/2)*2",
                "-hls_time", "10", "-hls_playlist_type", "vod", "-hls_segment_filename",
                str(temp_dir / f"{output_path.stem}_%03d.ts"), str(output_path)
            ]

            logging.info("Running ffmpeg command: " + ' '.join(ffmpeg_command))
            subprocess.run(ffmpeg_command, check=True)

            output_paths.append(output_path)  # Append each completed output file to the output_paths list

        master_playlist_path = create_master_playlist(output_paths, temp_dir)
        output_paths.append(master_playlist_path)

    return output_paths  # Return the list of completed output files

video_file = gr.inputs.File(label="Upload video file")
quality = gr.inputs.Slider(18, 28, 1, 23, label="Video quality (18-28, lower is better)")
aspect_ratio = gr.inputs.Textbox("16:9", label="Aspect ratio (width:height)")
video_url = gr.inputs.Textbox(label="Or enter video URL")

iface = gr.Interface(
    convert_video,
    [video_file, quality, aspect_ratio, video_url],
    gr.outputs.File(label="Download video file(s)"),
    title="Video Transcoder",
    description="Transcodes a video file or URL to multiple resolutions for adaptive streaming. Higher quality values reduce the video bitrate."
)

iface.launch()