#!/usr/bin/env python3
"""
Download Swedish auto-generated subtitles from YouTube videos using yt-dlp.
"""
import subprocess
import sys
import platform

def get_url_from_dialog():
    """
    Show a macOS dialog to get the YouTube URL.
    Uses osascript (AppleScript) - similar to zenity on Linux or prompt() in HTML.

    Returns:
        str: The URL entered by the user, or None if cancelled
    """
    if platform.system() != 'Darwin':
        print("Error: Dialog is only supported on macOS", file=sys.stderr)
        return None

    # AppleScript to show a text input dialog
    applescript = '''
    display dialog "Enter YouTube URL:" default answer "" with title "Download Swedish Subtitles" buttons {"Cancel", "OK"} default button "OK"
    set userInput to text returned of result
    return userInput
    '''

    try:
        result = subprocess.run(
            ['osascript', '-e', applescript],
            capture_output=True,
            text=True,
            check=True
        )
        return result.stdout.strip()
    except subprocess.CalledProcessError:
        # User cancelled or error occurred
        return None

def clean_subtitles(srt_content):
    """
    Clean SRT subtitle content by removing timestamps, unwrapping lines, and removing duplicates.

    Args:
        srt_content: Raw SRT subtitle content

    Returns:
        Cleaned text content with timestamps removed and duplicates filtered
    """
    lines = srt_content.strip().split('\n')
    text_lines = []
    seen_lines = set()

    for line in lines:
        line = line.strip()

        # Skip empty lines, sequence numbers, and timestamp lines
        if not line:
            continue
        if line.isdigit():
            continue
        if '-->' in line:
            continue

        # Skip duplicate lines (auto-generated subtitles often repeat)
        if line in seen_lines:
            continue

        seen_lines.add(line)
        text_lines.append(line)

    # Join all lines with spaces to unwrap
    return ' '.join(text_lines)

def download_subtitles(url):
    """
    Download auto-generated Swedish subtitles from a YouTube video or playlist.

    Args:
        url: YouTube video or playlist URL
    """
    import os
    import glob

    try:
        # Get video ID to construct subtitle filename
        # Download subtitles to current directory, then read and delete
        cmd = [
            'yt-dlp',
            '--write-auto-sub',
            '--sub-lang', 'sv',
            '--skip-download',
            '--convert-subs', 'srt',
            '-o', '%(id)s.%(ext)s',
            url
        ]

        print(f"Downloading subtitles...", file=sys.stderr)
        result = subprocess.run(cmd, capture_output=True, text=True, check=True)

        # Find the generated .srt file
        srt_files = glob.glob('*.sv.srt')

        if srt_files:
            subtitle_file = srt_files[0]
            print(f"Reading subtitles from: {subtitle_file}", file=sys.stderr)

            # Read, clean and print the subtitle file
            with open(subtitle_file, 'r', encoding='utf-8') as f:
                raw_content = f.read()
                cleaned_content = clean_subtitles(raw_content)
                print(cleaned_content)

            # Clean up the subtitle file
            os.remove(subtitle_file)
            print(f"Cleaned up: {subtitle_file}", file=sys.stderr)
        else:
            print("Error: No Swedish subtitles found for this video", file=sys.stderr)
            print("Available subtitle languages might not include Swedish auto-generated", file=sys.stderr)
            sys.exit(1)

    except subprocess.CalledProcessError as e:
        print(f"Error running yt-dlp: {e}", file=sys.stderr)
        if e.stderr:
            print(e.stderr, file=sys.stderr)
        sys.exit(1)
    except FileNotFoundError:
        print("Error: yt-dlp not found. Please install it first:", file=sys.stderr)
        print("  pip install yt-dlp", file=sys.stderr)
        sys.exit(1)
    except Exception as e:
        print(f"Unexpected error: {e}", file=sys.stderr)
        import traceback
        traceback.print_exc()
        sys.exit(1)

if __name__ == '__main__':
    url = None

    # Get URL from command line argument or dialog
    if len(sys.argv) == 2:
        url = sys.argv[1]
    elif len(sys.argv) == 1:
        # No argument provided - show dialog (macOS only)
        if platform.system() == 'Darwin':
            url = get_url_from_dialog()
            if not url:
                print("No URL provided. Exiting.", file=sys.stderr)
                sys.exit(1)
        else:
            print("Usage: python download-subs.py <youtube_url>", file=sys.stderr)
            sys.exit(1)
    else:
        print("Usage: python download-subs.py [youtube_url]", file=sys.stderr)
        print("  If no URL is provided on macOS, a dialog will appear.", file=sys.stderr)
        sys.exit(1)

    download_subtitles(url)