using System.ComponentModel;
using System.IO;
using System.Runtime.CompilerServices;

namespace Futonizer.Models;

/// <summary>
/// Represents one external subtitle file that was drag-and-dropped in and
/// matched to a <see cref="QueuedFileItem"/> by episode (e.g. "S04E06", or
/// just a bare episode number like "06"), to be muxed in as an additional
/// subtitle track when the file is processed.
/// </summary>
public class ExternalSubtitleTrack : INotifyPropertyChanged
{
    private bool _isDefault;

    public string FilePath { get; }
    public string FileName => Path.GetFileName(FilePath);

    /// <summary>Uppercased extension without the dot, e.g. "SRT", "ASS", "SUP".</summary>
    public string FormatDisplay => Path.GetExtension(FilePath).TrimStart('.').ToUpperInvariant();

    /// <summary>ISO 639-2 language code detected from the filename, or "und" if unknown.</summary>
    public string Language { get; init; } = "und";

    /// <summary>Track name to embed in the output file; may be empty.</summary>
    public string TrackName { get; init; } = string.Empty;

    public bool Forced { get; init; }
    public bool HearingImpaired { get; init; }

    /// <summary>
    /// Whether this is the subtitle track flagged default in the output.
    /// Exactly one external subtitle per file should have this set at a time.
    /// </summary>
    public bool IsDefault
    {
        get => _isDefault;
        set
        {
            if (_isDefault == value) return;
            _isDefault = value;
            OnPropertyChanged();
        }
    }

    /// <summary>Short "FORMAT · LANG" label shown as a chip in the UI.</summary>
    public string LanguageDisplay => $"{FormatDisplay} · {(string.Equals(Language, "und", StringComparison.OrdinalIgnoreCase) ? "UND" : Language.ToUpperInvariant())}";

    public ExternalSubtitleTrack(string filePath)
    {
        FilePath = filePath;
    }

    public event PropertyChangedEventHandler? PropertyChanged;

    private void OnPropertyChanged([CallerMemberName] string? name = null)
        => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
}