using System;
using System.IO;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Media;

namespace FreedomFighter;

/// <summary>
/// Replacement for TOmegaMusic: a flat list of "songs" where some entries are
/// streamed music (mp3 via MediaPlayer) and some are sound effects (wav).
/// Indices mirror OmegaMusic1.Songs in GameU.dfm.
/// </summary>
public class MusicManager
{
    public class Entry
    {
        readonly MusicManager _mgr;
        public string Name = "";
        public Song? Song;              // streamed music
        public SoundEffect? Effect;     // wav sfx
        public int Volume = 100;        // 0..100, Omega convention

        public Entry(MusicManager mgr) => _mgr = mgr;

        public void Play()
        {
            if (Song != null)
            {
                MediaPlayer.Volume = Volume / 100f;
                MediaPlayer.Play(Song);
                _mgr._current = this;
            }
            else if (Effect != null)
            {
                Effect.Play(Volume / 100f, 0, 0);
                Volume = 100;   // one-shot volume, like the original's per-play setting
            }
        }

        public void Stop()
        {
            if (Song != null && _mgr._current == this)
            {
                MediaPlayer.Stop();
                _mgr._current = null;
            }
        }

        /// <summary>Playback position in seconds (original used this in the intro).</summary>
        public double Position => Song != null && _mgr._current == this
            ? MediaPlayer.PlayPosition.TotalSeconds : 0;
    }

    Entry? _current;
    public Entry[] Songs = [];

    public void Load(string contentDir)
    {
        MediaPlayer.IsRepeating = true;   // OmegaMusic1.Loop was called every menu frame

        // Index order mirrors OmegaMusic1.Songs in GameU.dfm.
        // [1] 'Level test.mp3' is lost — Track06.mp3 substitutes.
        // [3] gameover was a MIDI (Nazi_Rap.mid); MonoGame has no MIDI playback, so it is silent.
        (string name, string? file)[] entries =
        [
            ("level1", @"music\white light.mp3"),
            ("level2", @"music\Track06.mp3"),
            ("level3", @"music\G2 Final.mp3"),
            ("gameover", null),
            ("title", @"music\Main Menu 2.mp3"),
            ("fire1", @"sfx\fire1.wav"),
            ("reload", @"sfx\reload.wav"),
            ("thump", @"sfx\thump1.wav"),
            ("beep", @"sfx\beep.wav"),
            ("credits", @"music\G8 Final.mp3"),
            ("hit", @"sfx\hit4.wav"),
            ("explosion", @"sfx\explode2.wav"),
            ("level4", @"music\Thunderization.mp3"),
            ("missile", @"sfx\missile.wav"),
            ("intro", @"music\Intro.mp3"),
        ];

        Songs = new Entry[entries.Length];
        for (int i = 0; i < entries.Length; i++)
        {
            var e = new Entry(this) { Name = entries[i].name };
            var file = entries[i].file;
            if (file != null)
            {
                string path = Path.Combine(contentDir, file);
                if (File.Exists(path))
                {
                    try
                    {
                        if (path.EndsWith(".wav", StringComparison.OrdinalIgnoreCase))
                        {
                            using var fs = File.OpenRead(path);
                            e.Effect = SoundEffect.FromStream(fs);
                        }
                        else
                        {
                            e.Song = Song.FromUri(entries[i].name, new Uri(path, UriKind.Absolute));
                        }
                    }
                    catch (Exception ex)
                    {
                        Console.WriteLine($"Audio load failed for {file}: {ex.Message}");
                    }
                }
            }
            Songs[i] = e;
        }
    }
}