using AcDream.App.UI;
using AcDream.App.UI.Layout;
using AcDream.Core.Chat;
using AcDream.UI.Abstractions;
using AcDream.UI.Abstractions.Panels.Chat;

namespace AcDream.App.Tests.UI.Layout;

/// <summary>
/// Dat-free conformance tests for the committed chat_21000006.json golden fixture.
/// Verifies that LayoutImporter.ImportInfos correctly resolves the BaseElement /
/// BaseLayoutId inheritance chain for the chat window (LayoutDesc 0x21000006).
/// </summary>
public class ChatLayoutConformanceTests
{
    private static (uint, int, int) NoTex(uint _) => (0, 0, 0);

    private static ElementInfo? Find(ElementInfo n, uint id)
    {
        if (n.Id == id) return n;
        foreach (var c in n.Children)
        {
            var f = Find(c, id);
            if (f is not null) return f;
        }
        return null;
    }

    [Fact]
    public void ChatFixture_ResolvesKnownElements()
    {
        var root = FixtureLoader.LoadChatInfos();
        Assert.NotNull(Find(root, 0x10000011u)); // transcript
        Assert.NotNull(Find(root, 0x10000016u)); // input
        Assert.NotNull(Find(root, 0x10000012u)); // scrollbar track
        Assert.NotNull(Find(root, 0x10000014u)); // channel menu
        Assert.NotNull(Find(root, 0x10000019u)); // send button
        Assert.NotNull(Find(root, 0x1000046Fu)); // max/min button
    }

    [Fact]
    public void ChatFixture_ResolvedTypes_MatchRetailRegistry()
    {
        var root = FixtureLoader.LoadChatInfos();
        Assert.Equal(6u,  Find(root, 0x10000014u)!.Type);  // Menu
        Assert.Equal(11u, Find(root, 0x10000012u)!.Type);  // Scrollbar
        Assert.Equal(1u,  Find(root, 0x10000019u)!.Type);  // Button (Send)
        Assert.Equal(1u,  Find(root, 0x1000046Fu)!.Type);  // Button (Max/Min)
        Assert.Equal(12u, Find(root, 0x10000011u)!.Type);  // Text/style-prototype (transcript)
        Assert.Equal(12u, Find(root, 0x10000016u)!.Type);  // Text/style-prototype (input)
    }

    [Fact]
    public void ChatFixture_BuildsSelectableTranscriptAndEditableInputInPlace()
    {
        var layout = FixtureLoader.LoadChat();

        var transcript = Assert.IsType<UiText>(layout.FindElement(0x10000011u));
        var input = Assert.IsType<UiField>(layout.FindElement(0x10000016u));

        Assert.True(transcript.Selectable);
        Assert.True(input.Selectable);
        Assert.True(input.OneLine);
        Assert.Equal(0x10000016u, input.DatElementId);
    }

    [Fact]
    public void ChatFixture_ScrollbarImportsInheritedMediaRoles()
    {
        var layout = FixtureLoader.LoadChat();
        var scrollbar = Assert.IsType<UiScrollbar>(layout.FindElement(0x10000012u));

        Assert.Equal(0x06004C5Fu, scrollbar.TrackSprite);
        Assert.Equal(0x06004C60u, scrollbar.ThumbTopSprite);
        Assert.Equal(0x06004C63u, scrollbar.ThumbSprite);
        Assert.Equal(0x06004C66u, scrollbar.ThumbBotSprite);
        Assert.Equal(0x06004C69u, scrollbar.UpSprite);
        Assert.Equal(0x06004C6Cu, scrollbar.DownSprite);
    }

    [Fact]
    public void ChatFixture_WindowRootCarriesRetailHeightConstraints()
    {
        var root = FixtureLoader.LoadChatInfos();
        var window = Find(root, 0x1000000Eu)!;

        Assert.True(window.TryGetEffectiveInteger(0x3Eu, out int minHeight));
        Assert.True(window.TryGetEffectiveInteger(0x3Cu, out int maxHeight));
        Assert.Equal(100, minHeight);
        Assert.Equal(360, maxHeight);
    }

    [Fact]
    public void ChatFixture_CroppedDockedRoot_ReflowsContentAcrossMountedWidth()
    {
        var infos = FixtureLoader.LoadChatInfos();
        var layout = LayoutImporter.Build(infos, NoTex, null);
        var controller = ChatWindowController.Bind(
            infos,
            layout,
            new ChatVM(new ChatLog()),
            () => NullCommandBus.Instance,
            null,
            null,
            NoTex);
        Assert.NotNull(controller);

        var root = controller!.Root;
        root.Width = 490;
        root.Height = 100;
        root.RebaseChildLayoutBaselines();
        root.Width = 615;

        var transcriptPanel = layout.FindElement(0x10000010u)!;
        var inputBar = layout.FindElement(0x10000013u)!;
        transcriptPanel.ApplyAnchor(root.Width, root.Height);
        inputBar.ApplyAnchor(root.Width, root.Height);

        Assert.Equal(615f, transcriptPanel.Width);
        Assert.Equal(615f, inputBar.Width);
    }

    [Fact]
    public void ChatFixture_ChannelCaptionWidth_SurvivesImportedLayoutPass()
    {
        var infos = FixtureLoader.LoadChatInfos();
        var layout = LayoutImporter.Build(infos, NoTex, null);
        var controller = ChatWindowController.Bind(
            infos,
            layout,
            new ChatVM(new ChatLog()),
            () => NullCommandBus.Instance,
            null,
            null,
            NoTex);
        Assert.NotNull(controller);

        controller!.Menu.OnSelect!.Invoke(ChatChannelKind.General);
        float fittedWidth = controller.Menu.Width;
        controller.Menu.ApplyAnchor(controller.Menu.Parent!.Width, controller.Menu.Parent.Height);

        Assert.True(fittedWidth > 46f);
        Assert.Equal(fittedWidth, controller.Menu.Width);
        Assert.Equal(controller.Menu.Left + fittedWidth, controller.Input.Left);
    }

    [Fact]
    public void ChatMaximize_ResizesOuterFrameByHalfParent_AndRestores()
    {
        var infos = FixtureLoader.LoadChatInfos();
        var layout = LayoutImporter.Build(infos, NoTex, null);
        var controller = ChatWindowController.Bind(
            infos,
            layout,
            new ChatVM(new ChatLog()),
            () => NullCommandBus.Instance,
            null,
            null,
            NoTex)!;
        var root = new UiRoot { Width = 800, Height = 600 };
        RetailWindowHandle handle = RetailWindowFrame.Mount(
            root,
            controller.Root,
            NoTex,
            new RetailWindowFrame.Options
            {
                WindowName = WindowNames.Chat,
                Chrome = RetailWindowChrome.NineSlice,
                Left = 12f,
                Top = 390f,
                ContentWidth = 490f,
                ContentHeight = controller.Root.Height,
                RebaseContentLayout = true,
                DatConstraintSource = controller.DatWindowInfo,
                MinWidth = 200f,
            });
        controller.AttachWindow(handle);
        var maxMin = Assert.IsType<UiButton>(layout.FindElement(0x1000046Fu));

        maxMin.OnClick!();

        Assert.True(controller.IsMaximized);
        Assert.Equal(90f, handle.Top);
        Assert.Equal(370f, handle.Height); // DAT max 360 + 2*5px shared chrome
        Assert.Equal(RetailUiStateIds.Maximized, maxMin.ActiveRetailStateId);
        controller.Root.ApplyAnchor(handle.Width, handle.Height);
        Assert.Equal(360f, controller.Root.Height);

        maxMin.OnClick!();

        Assert.False(controller.IsMaximized);
        Assert.Equal(390f, handle.Top);
        Assert.Equal(110f, handle.Height);
        Assert.Equal(RetailUiStateIds.Minimized, maxMin.ActiveRetailStateId);
    }

    [Fact]
    public void MountedChatScrollbar_ButtonsAndThumbDragDriveTranscriptModel()
    {
        var infos = FixtureLoader.LoadChatInfos();
        var layout = LayoutImporter.Build(infos, NoTex, null);
        var controller = ChatWindowController.Bind(
            infos,
            layout,
            new ChatVM(new ChatLog()),
            () => NullCommandBus.Instance,
            null,
            null,
            NoTex)!;
        var root = new UiRoot { Width = 800, Height = 600 };
        RetailWindowHandle handle = RetailWindowFrame.Mount(
            root,
            controller.Root,
            NoTex,
            new RetailWindowFrame.Options
            {
                WindowName = WindowNames.Chat,
                Chrome = RetailWindowChrome.NineSlice,
                Left = 10f,
                Top = 440f,
                ContentWidth = 490f,
                ContentHeight = controller.Root.Height,
                RebaseContentLayout = true,
                DatConstraintSource = controller.DatWindowInfo,
                MinWidth = 200f,
            });
        controller.AttachWindow(handle);

        UiScrollbar bar = controller.Scrollbar;
        UiScrollable scroll = controller.Transcript.Scroll;
        scroll.LineHeight = 16;
        scroll.SetExtents(contentHeight: 400, viewHeight: 50, preserveEnd: true);
        Assert.Equal(350, scroll.ScrollY);

        var screen = bar.ScreenPosition;
        int centerX = (int)(screen.X + bar.Width / 2f);

        // Top/decrement button.
        int upY = (int)(screen.Y + 8f);
        root.OnMouseDown(UiMouseButton.Left, centerX, upY);
        root.OnMouseUp(UiMouseButton.Left, centerX, upY);
        Assert.Equal(334, scroll.ScrollY);

        // Re-layout must retain the position chosen through the scrollbar.
        scroll.SetExtents(contentHeight: 400, viewHeight: 50, preserveEnd: true);
        Assert.Equal(334, scroll.ScrollY);

        // Drag the thumb toward the top of the track.
        float trackTop = 16f;
        float trackLength = bar.Height - 32f;
        var (thumbY, thumbHeight) = UiScrollbar.ThumbRect(scroll, trackTop, trackLength);
        int dragStartY = (int)(screen.Y + thumbY + thumbHeight / 2f);
        int dragEndY = (int)(screen.Y + trackTop + thumbHeight / 2f);
        root.OnMouseDown(UiMouseButton.Left, centerX, dragStartY);
        root.OnMouseMove(centerX, dragEndY);
        root.OnMouseUp(UiMouseButton.Left, centerX, dragEndY);

        Assert.True(scroll.ScrollY < 334);
        int draggedPosition = scroll.ScrollY;
        scroll.SetExtents(contentHeight: 400, viewHeight: 50, preserveEnd: true);
        Assert.Equal(draggedPosition, scroll.ScrollY);
    }
}