using System.Collections.Frozen;
using System.Collections.Generic;

namespace AcDream.Core.Audio;

/// <summary>
/// Retail's <c>AdminEnvirons</c> code → interface <see cref="SoundId"/> table,
/// from the switch in <c>CPlayerSystem::Handle_Admin__Environs</c> @
/// <c>0x0055DE20</c> (<c>0x0055E07F..0x0055E2C7</c>). Each case plays
/// <c>SoundManager::PlaySoundFromCenter(Sound_UI_*, GetUISoundTable())</c> after
/// checking that the local player physics object and the UI table both exist.
///
/// <para>
/// This is what players remember as dungeon "music": the server drives the
/// chanting, drums, whispers and thunder through these codes. It is not a music
/// system — retail has none — but it is the atmosphere channel.
/// </para>
///
/// <para>
/// <b>An explicit table, deliberately.</b> The environ code and the SoundType
/// differ by 0x11 for most of the run, but NOT uniformly: codes <c>0x73</c> and
/// <c>0x74</c> have no case at all (retail falls through and plays nothing), so
/// <c>0x75</c> lands on <c>UI_Squeal</c> (0x84) rather than the 0x86 arithmetic
/// would give. Retail's switch is explicit; porting it as an offset would
/// mis-map every code from <c>0x75</c> up.
/// </para>
/// </summary>
public static class EnvironSoundCueMap
{
    private static readonly FrozenDictionary<uint, SoundId> Map =
        new Dictionary<uint, SoundId>
        {
            [0x65u] = SoundId.UI_Roar,
            [0x66u] = SoundId.UI_Bell,
            [0x67u] = SoundId.UI_Chant1,
            [0x68u] = SoundId.UI_Chant2,
            [0x69u] = SoundId.UI_DarkWhispers1,
            [0x6Au] = SoundId.UI_DarkWhispers2,
            [0x6Bu] = SoundId.UI_DarkLaugh,
            [0x6Cu] = SoundId.UI_DarkWind,
            [0x6Du] = SoundId.UI_DarkSpeech,
            [0x6Eu] = SoundId.UI_Drums,
            [0x6Fu] = SoundId.UI_GhostSpeak,
            [0x70u] = SoundId.UI_Breathing,
            [0x71u] = SoundId.UI_Howl,
            [0x72u] = SoundId.UI_LostSouls,
            // 0x73 and 0x74: no case in retail's switch — nothing plays.
            [0x75u] = SoundId.UI_Squeal,
            [0x76u] = SoundId.UI_Thunder1,
            [0x77u] = SoundId.UI_Thunder2,
            [0x78u] = SoundId.UI_Thunder3,
            [0x79u] = SoundId.UI_Thunder4,
            [0x7Au] = SoundId.UI_Thunder5,
            [0x7Bu] = SoundId.UI_Thunder6,
        }.ToFrozenDictionary();

    /// <summary>
    /// Map an <c>AdminEnvirons</c> change type to its interface sound, or false
    /// when retail's switch has no case for it (including <c>0x73</c>/<c>0x74</c>
    /// inside the run, and every code outside it).
    /// </summary>
    public static bool TryGetSound(uint changeType, out SoundId sound) =>
        Map.TryGetValue(changeType, out sound);

    /// <summary>Every code retail has a case for. Diagnostic and test use.</summary>
    public static IReadOnlyCollection<uint> Codes => Map.Keys;
}