import os
import re
import subprocess
import logging

from aniworld.models import Anime
from aniworld.config import PROVIDER_HEADERS, INVALID_PATH_CHARS
from aniworld.parser import arguments

# Configure logging
logging.basicConfig(
    filename="download.log",
    level=logging.INFO,
    format="%(asctime)s - %(levelname)s - %(message)s"
)

# Read timeout from environment variable, default to 600 seconds (10 minutes)
timeout = int(os.getenv("DOWNLOAD_TIMEOUT", 600))

def download(anime: Anime):  # pylint: disable=too-many-branches
    for episode in anime:
        sanitized_anime_title = ''.join(
            char for char in anime.title if char not in INVALID_PATH_CHARS
        )

        if episode.season == 0:
            output_file = (
                f"{sanitized_anime_title} - "
                f"Movie {episode.episode:02} - "
                f"({anime.language}).mp4"
            )
        else:
            output_file = (
                f"{sanitized_anime_title} - "
                f"S{episode.season:02}E{episode.episode:03} - "
                f"({anime.language}).mp4"
            )

        output_path = os.path.join(anime.output_directory, output_file)
        os.makedirs(os.path.dirname(output_path), exist_ok=True)

        logging.info(f"Preparing to download: {output_path}")

        command = [
            "yt-dlp",
            episode.get_direct_link(anime.provider, anime.language),
            "--fragment-retries", "infinite",
            "--concurrent-fragments", "4",
            "-o", output_path,
            "--quiet",
            "--no-warnings",
            "--progress"
        ]

        if anime.provider in PROVIDER_HEADERS:
            for header in PROVIDER_HEADERS[anime.provider]:
                command.extend(["--add-header", header])

        if arguments.only_command:
            logging.info(
                f"{anime.title} - S{episode.season}E{episode.episode} - ({anime.language}): "
                f"{' '.join(str(item) if item is not None else '' for item in command)}"
            )
            continue

        try:

            logging.info(f"Starting download to {output_path}...")
            subprocess.run(command, check=True, timeout=timeout)
            logging.info(f"Download completed: {output_path}")
        except subprocess.TimeoutExpired:
            logging.error(f"Download timed out after {timeout} seconds: {' '.join(str(item) for item in command)}")
        except subprocess.CalledProcessError:
            logging.error(f"Error running command: {' '.join(str(item) for item in command)}")
        except KeyboardInterrupt:
            logging.warning("Download interrupted by user.")
            output_dir = os.path.dirname(output_path)
            is_empty = True

            for file_name in os.listdir(output_dir):
                if re.search(r'\.(part|ytdl|part-Frag\d+)$', file_name):
                    os.remove(os.path.join(output_dir, file_name))
                else:
                    is_empty = False

            if is_empty or not os.listdir(output_dir):
                os.rmdir(output_dir)
                logging.info(f"Removed empty download directory: {output_dir}")