import os
from typing import List
from app.utils.logger import logger

def load_local_playlist(playlist_path: str) -> List[str]:
    """
    Load a local playlist from a m3u or m3u8 file.
    Skip # comments and empty lines.

    Args:
        playlist_path (str): The path to the playlist file.

    Returns:
        list: A list of songs in the playlist.
    """
    try:
        result = []
        with open(playlist_path, 'r', encoding="utf-8") as file:
            for line in file:
                line = line.strip()
                if not line:
                    # Skip empty lines
                    continue
                if line.startswith('#'):
                    # Skip comments
                    continue
                result.append(line)
        logger.info(f"Loaded {len(result)} songs from the playlist: {playlist_path}")
        return result
    except FileNotFoundError:
        logger.error(f"Error: The file {playlist_path} does not exist.")
        return []
    except Exception as e:
        logger.error(f"An error occurred while loading the playlist: {e}")
        return []


def scan_local_playlists(base_path: str) -> list[dict]:
    """Scan a directory for playlist files and return their basic info.

    Args:
        base_path: Directory that contains playlist files.

    Returns:
        A list of dictionaries with ``name`` and ``track_count`` keys.
    """

    playlists: list[dict] = []
    if not base_path:
        logger.warning("No base path provided for local playlists scan.")
        return playlists

    absolute_path = os.path.abspath(base_path)
    if not os.path.isdir(absolute_path):
        logger.warning(f"Playlist path does not exist or is not a directory: {absolute_path}")
        return playlists

    for entry in os.scandir(absolute_path):
        if not entry.is_file():
            continue
        if not entry.name.lower().endswith((".m3u", ".m3u8")):
            continue
        tracks = load_local_playlist(entry.path)
        playlists.append({"name": entry.name, "track_count": len(tracks)})

    playlists.sort(key=lambda item: item["name"].lower())
    logger.info(f"Found {len(playlists)} playlists under {absolute_path}.")
    return playlists
def write_local_playlist(playlist_path: str, tracks: List[str]) -> bool:
    """
    Write a list of tracks to a local playlist file.

    Args:
        playlist_path (str): The path to the playlist file.
        tracks (list): A list of songs to write to the playlist.

    Returns:
        bool: True if successful, False otherwise.
    """
    try:
        with open(playlist_path, 'w', encoding="utf-8") as file:
            file.write("#EXTM3U\n")
            for track in tracks:
                file.write(f"{track}\n")
        logger.info(f"Written {len(tracks)} songs to the playlist: {playlist_path}")
        return True
    except Exception as e:
        logger.error(f"An error occurred while writing the playlist {playlist_path}: {e}")
        return False


def delete_local_playlist(playlist_path: str) -> bool:
    """
    Delete a local playlist file.

    Args:
        playlist_path (str): The path to the playlist file.

    Returns:
        bool: True if successful, False otherwise.
    """
    try:
        if os.path.exists(playlist_path):
            os.remove(playlist_path)
            logger.info(f"Deleted playlist: {playlist_path}")
            return True
        else:
            logger.warning(f"Playlist not found for deletion: {playlist_path}")
            return False
    except Exception as e:
        logger.error(f"An error occurred while deleting the playlist {playlist_path}: {e}")
        return False