using System.Diagnostics.CodeAnalysis;
using ADOFAIRenderer.Util;
using MelonLoader;
using O5Kit.Core;
using TMPro;

namespace ADOFAIRenderer.UI;

using UnityEngine;

/// <summary>
/// Assets loaded from the mod's embedded asset bundles (fonts and the color conversion compute shader).
/// <para>
/// <see cref="Load"/> is called once from <c>RenderMod.OnInitializeMelon</c>; the fields stay <c>null</c> until then.
/// Bundles are obtained from <c>BundleLoader.GetBundle</c> by name ("fonts", "shaders"). Main thread only.
/// </para>
/// </summary>
[SuppressMessage("ReSharper", "MemberCanBePrivate.Global")]
internal static class ModAssets
{
    /// <summary>
    /// Loads the font and shader bundles and the assets inside them, logging after each bundle.
    /// Exceptions from bundle or asset loading are not caught here and propagate to the caller.
    /// </summary>
    public static void Load()
    {
        FontBundle = BundleLoader.GetBundle("fonts");
        NanumSquareNeoNormal = FontBundle.LoadAsset<TMP_FontAsset>("NanumSquareNeoOTF-Bd SDF");
        NanumSquareNeoBold = FontBundle.LoadAsset<TMP_FontAsset>("NanumSquareNeoOTF-Eb SDF");
        Melon<RenderMod>.Logger.Msg("Fonts loaded successfully.");
            
        ShaderBundle = BundleLoader.GetBundle("shaders");
        ColorConversionShader = ShaderBundle.LoadAsset<ComputeShader>("ColorConversion");
        Melon<RenderMod>.Logger.Msg("Shader loaded successfully.");
    }

    /// <summary>Asset bundle "fonts" holding the TextMeshPro font assets.</summary>
    public static AssetBundle FontBundle = null!;
    /// <summary>Asset bundle "shaders" holding the compute shaders.</summary>
    public static AssetBundle ShaderBundle = null!;

    /// <summary>
    /// NanumSquare Neo, asset "NanumSquareNeoOTF-Bd SDF" (Bd = Bold weight). Used as the regular UI font of the mod
    /// (O5Kit <see cref="RendererFontProvider.Regular"/>, DebugMonitorUI text).
    /// </summary>
    public static TMP_FontAsset NanumSquareNeoNormal = null!;
    /// <summary>
    /// NanumSquare Neo, asset "NanumSquareNeoOTF-Eb SDF" (Eb = ExtraBold weight). Used as the O5Kit medium font
    /// (<see cref="RendererFontProvider.Medium"/>).
    /// </summary>
    public static TMP_FontAsset NanumSquareNeoBold = null!;

    /// <summary>
    /// Compute shader "ColorConversion" that converts captured frames to the encoder's YUV pixel format on the GPU
    /// (used by FrameReader).
    /// </summary>
    public static ComputeShader ColorConversionShader = null!;
}

/// <summary>
/// O5Kit font provider for the mod's UI: the bundled NanumSquare Neo fonts for regular and medium text, and O5Kit's
/// default monospace font.
/// </summary>
internal sealed class RendererFontProvider : IFontProvider
{
    /// <summary>O5Kit default provider, used only for <see cref="Monospace"/>.</summary>
    private static readonly DefaultFontProvider DefaultFontProvider = new();
    private bool _disposed;

    /// <summary>Regular text font: <see cref="ModAssets.NanumSquareNeoNormal"/>.</summary>
    public TMP_FontAsset Regular => ModAssets.NanumSquareNeoNormal;
    /// <summary>Medium (emphasis) text font: <see cref="ModAssets.NanumSquareNeoBold"/>.</summary>
    public TMP_FontAsset Medium => ModAssets.NanumSquareNeoBold;
    /// <summary>Monospace font (e.g. hex color input): O5Kit's default monospace font.</summary>
    public TMP_FontAsset Monospace => DefaultFontProvider.Monospace;

    /// <summary>
    /// Marks the provider disposed. The font assets belong to <see cref="ModAssets"/> and are not unloaded.
    /// </summary>
    public void Dispose()
    {
        if (_disposed) return;
        _disposed = true;
    }
}

/// <summary>
/// Owner of the mod's O5Kit UI: the shared <see cref="O5Context"/> (config, theme, fonts) and the window manager
/// with its canvas.
/// <para>
/// Added once by <c>RenderMod.OnInitializeMelon</c> to a GameObject kept across scene loads. Other UI code reads
/// <see cref="Context"/> and <see cref="WindowManager"/> through the static <see cref="Instance"/>.
/// <see cref="Update"/> drives O5Kit's per-frame work (object ticks, tooltip, keyboard shortcuts). Main thread only.
/// </para>
/// </summary>
internal class RendererUIManager : MonoBehaviour
{
    /// <summary>The single instance, assigned in <see cref="Awake"/>.</summary>
    public static RendererUIManager Instance = null!;

    /// <summary>Shared O5Kit context used to build every mod window and dialog.</summary>
    public static O5Context Context => Instance._context;
    /// <summary>Window manager whose canvas holds the mod windows (e.g. RenderConfigWindow).</summary>
    public O5WindowManager WindowManager => _windowManager;

    private O5Context _context = null!;
    private O5WindowManager _windowManager = null!;

    /// <summary>
    /// Creates the O5Kit context with the mod theme and fonts, then the window manager and its canvas
    /// ("RendererMod_Canvas"), and lowers that canvas's sorting order to <see cref="WindowCanvasSortingOrder"/>.
    /// </summary>
    private void Awake() {
        Instance = this;

        // O5Kit config: UI scale 1.0, middle click resets a control to its default value, slider drag sensitivity 1.0.
        // Theme: O5Kit's dark theme with the mod colors. Colors are RGBA 0..1; the accent color
        // (1.000, 0.294, 0.079) is orange-red (#FF4B14 approx.). Sizes are canvas units: corner radius 12,
        // outline width 2, control height 40, body font 18, H1 font 48.
        _context = new O5Context(
            config: new O5Config {
                UIScale = 1.0f,
                MiddleClickToDefault = true,
                SliderSensitivity = 1.0f
            },
            theme: O5Theme.Dark with
            {
                PanelBG = new Color(0.067f, 0.067f, 0.067f, 1f),
                TopBar = new Color(0f, 0f, 0f, 0.6f),
                MenuBG = new Color(0f, 0f, 0f, 0.6f),
                MenuHover = new Color(1.000f, 0.294f, 0.079f, .6f),
                ObjectBG = new Color(0f, 0f, 0f, 1f),
                ObjectButton = new Color(0f, 0f, 0f, 1f),
                ObjectActive = new Color(1.000f, 0.294f, 0.079f, 1f),
                ObjectActiveBright = new Color(1.000f, 0.294f, 0.079f, 1f),
                ControlOutlineIdle = new Color(1f, 1f, 1f, 0.4f),
                ButtonHover = new Color(0.133f, 0.133f, 0.133f, 1.0f),
                ControlOutlineHover = new Color(1f, 1f, 1f, 0.4f),
                CardHeader = new Color(0.157f, 0f, 0f, 1f),
                CardPanel = new Color(0, 0, 0, 0f),
                SoftRed = new Color(1.000f, 0.576f, 0.590f, 1f),
                MathOk = new Color(0.408f, 0.827f, 0.569f, 1f),
                MathWarn = new Color(0.964f, 0.647f, 0.315f, 1f),
                MathErr = new Color(1.000f, 0.576f, 0.590f, 1f),
                CornerRadius = 12, OutlineWidth = 2, ControlHeight = 40, FontSizeBody = 18, FontSizeH1 = 48,
                Outline = new Color(1f, 1f, 1f, 0.2f),
                TextDimAlpha = 1f
            },
            fonts: new RendererFontProvider()
        );
        
        _windowManager = O5WindowManager.Create(_context, transform, "RendererMod_Canvas");

        // The O5Kit canvas is created with sortingOrder 32767. It is lowered so that the dialogs of
        // CommonWarningDialogUI (32766) are drawn above the windows of this manager.
        var windowCanvas = transform.Find("RendererMod_Canvas")?.GetComponent<Canvas>();
        if (windowCanvas != null) windowCanvas.sortingOrder = WindowCanvasSortingOrder;
    }
    
    /// <summary>
    /// Sorting order of the window canvas: below CommonWarningDialogUI (32766) and FFmpegDownloadUI (32767), above the
    /// render overlays (DebugMonitorUI 9999, EscapeHandlerUI 10000).
    /// </summary>
    private const int WindowCanvasSortingOrder = 32000;

    /// <summary>Runs O5Kit's per-frame updates: object ticks, tooltip, and keyboard shortcut handling.</summary>
    private void Update() {
        O5Object.TickAll();
        Context.Tooltip.Tick();
        O5Kit.Input.O5ShortcutManager.HandleUpdate();
    }
    
    /// <summary>Disposes the window manager, then the context.</summary>
    private void OnDestroy() {
        _windowManager.Dispose();
        _context.Dispose();
    }
}