using System.Collections.Generic;
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>
/// Smoke tests for <see cref="ChatWindowController.Bind"/> — no dats, no GL.
///
/// Building the Type-12 "skipped" elements via the pure <see cref="LayoutImporter"/>
/// path is the correct approach: we build a synthetic info tree that reflects the
/// real chat layout hierarchy (root → transcript panel + input bar as Type-3
/// containers, with Type-12 children for transcript + input, plus a Type-3 track
/// and menu), call <see cref="LayoutImporter.Build"/> to get the widget tree
/// (Type-12 children skipped, Type-3 parents created), then call
/// <see cref="ChatWindowController.Bind"/> which reads rects from the info tree
/// and places behavioral widgets under the parent containers.
/// </summary>
public class ChatWindowControllerTests
{
    // ── Null-resolve helper (no GL needed) ─────────────────────────────────
    private static (uint, int, int) NoTex(uint _) => (0u, 0, 0);

    // ── Capture bus — records every Publish call ────────────────────────────
    private sealed class CaptureBus : ICommandBus
    {
        public readonly List<object> Published = new();
        public void Publish<T>(T cmd) where T : notnull => Published.Add(cmd!);
    }

    // ── Synthetic element tree matching the real chat layout topology ────────

    /// <summary>
    /// Build a minimal synthetic ElementInfo tree that mirrors the real chat
    /// layout (0x21000006) with enough fidelity for Bind to succeed:
    ///   root (Type-3)
    ///     transcriptPanel (Type-3) [0x10000010]
    ///       transcript    (Type-12, no media) [0x10000011]  ← skipped by factory
    ///       track         (Type-3)  [0x10000012]
    ///     inputBar        (Type-3) [0x10000013]
    ///       menu          (Type-3)  [0x10000014]
    ///       input         (Type-12, no media) [0x10000016]  ← skipped by factory
    ///       send          (Type-3)  [0x10000019]
    ///     maxmin          (Type-3) [0x1000046F]
    /// </summary>
    private static (ElementInfo rootInfo, ImportedLayout layout, ChatVM vm) BuildTestTree()
    {
        var transcriptNode = new ElementInfo
        {
            Id = 0x10000011u, Type = 12,  // Type-12, no media → skipped by factory
            X = 16, Y = 0, Width = 458, Height = 74,
        };
        var trackNode = new ElementInfo
        {
            Id = 0x10000012u, Type = 3,
            X = 474, Y = 6, Width = 16, Height = 68,
        };
        var transcriptPanel = new ElementInfo
        {
            Id = 0x10000010u, Type = 3, X = 0, Y = 9, Width = 490, Height = 74,
        };
        transcriptPanel.Children.Add(transcriptNode);
        transcriptPanel.Children.Add(trackNode);

        var menuNode = new ElementInfo
        {
            Id = 0x10000014u, Type = 3, X = 0, Y = 0, Width = 46, Height = 17,
        };
        var inputNode = new ElementInfo
        {
            Id = 0x10000016u, Type = 12,  // Type-12, no media → skipped by factory
            X = 46, Y = 0, Width = 398, Height = 17,
        };
        var sendNode = new ElementInfo
        {
            Id = 0x10000019u, Type = 3, X = 444, Y = 0, Width = 46, Height = 17,
        };
        var inputBar = new ElementInfo
        {
            Id = 0x10000013u, Type = 3, X = 0, Y = 83, Width = 490, Height = 17,
        };
        inputBar.Children.Add(menuNode);
        inputBar.Children.Add(inputNode);
        inputBar.Children.Add(sendNode);

        var maxMinNode = new ElementInfo
        {
            Id = 0x1000046Fu, Type = 3, X = 474, Y = 0, Width = 16, Height = 16,
        };

        var root = new ElementInfo
        {
            Id = 0x1000000Eu, Type = 3, Width = 490, Height = 100,
        };
        root.Children.Add(transcriptPanel);
        root.Children.Add(inputBar);
        root.Children.Add(maxMinNode);

        var layout = LayoutImporter.Build(root, NoTex, null);
        var vm = new ChatVM(new ChatLog());
        return (root, layout, vm);
    }

    // ── Test 1: Bind returns non-null with the minimal tree ──────────────────

    [Fact]
    public void Bind_Returns_NonNull_OnValidTree()
    {
        var (rootInfo, layout, vm) = BuildTestTree();
        var bus = new CaptureBus();

        var ctrl = ChatWindowController.Bind(rootInfo, layout, vm, bus, null, null, NoTex);

        Assert.NotNull(ctrl);
    }

    // ── Test 2: Transcript is placed as a child of the transcript panel ──────

    [Fact]
    public void Bind_Transcript_IsChildOfTranscriptPanel()
    {
        var (rootInfo, layout, vm) = BuildTestTree();
        var bus = new CaptureBus();

        var ctrl = ChatWindowController.Bind(rootInfo, layout, vm, bus, null, null, NoTex);

        Assert.NotNull(ctrl);
        var panel = layout.FindElement(0x10000010u);
        Assert.NotNull(panel);
        // The transcript widget must be a child of the transcript panel.
        Assert.Contains(ctrl!.Transcript, panel!.Children);
    }

    // ── Test 3: Input is placed as a child of the input bar ─────────────────

    [Fact]
    public void Bind_Input_IsChildOfInputBar()
    {
        var (rootInfo, layout, vm) = BuildTestTree();
        var bus = new CaptureBus();

        var ctrl = ChatWindowController.Bind(rootInfo, layout, vm, bus, null, null, NoTex);

        Assert.NotNull(ctrl);
        var bar = layout.FindElement(0x10000013u);
        Assert.NotNull(bar);
        Assert.Contains(ctrl!.Input, bar!.Children);
    }

    // ── Test 4: Input.OnSubmit publishes SendChatCmd via the capture bus ─────

    [Fact]
    public void Bind_InputSubmit_PublishesSendChatCmd()
    {
        var (rootInfo, layout, vm) = BuildTestTree();
        var bus = new CaptureBus();

        var ctrl = ChatWindowController.Bind(rootInfo, layout, vm, bus, null, null, NoTex);

        Assert.NotNull(ctrl);
        ctrl!.Input.OnSubmit!.Invoke("hello world");

        // ChatCommandRouter.Submit should have published a SendChatCmd.
        Assert.Single(bus.Published);
        var cmd = Assert.IsType<SendChatCmd>(bus.Published[0]);
        Assert.Equal("hello world", cmd.Text);
    }

    // ── Test 5: Channel change updates the channel used by subsequent submits ─

    [Fact]
    public void Bind_ChannelChange_UpdatesSubmitChannel()
    {
        var (rootInfo, layout, vm) = BuildTestTree();
        var bus = new CaptureBus();

        var ctrl = ChatWindowController.Bind(rootInfo, layout, vm, bus, null, null, NoTex);

        Assert.NotNull(ctrl);
        // Switch channel to General.
        ctrl!.Menu.OnChannelChanged!.Invoke(ChatChannelKind.General);
        ctrl.Input.OnSubmit!.Invoke("hey all");

        Assert.Single(bus.Published);
        var cmd = Assert.IsType<SendChatCmd>(bus.Published[0]);
        Assert.Equal(ChatChannelKind.General, cmd.Channel);
    }

    // ── Test 6: Bind returns null when required elements are absent ──────────

    [Fact]
    public void Bind_Returns_Null_WhenTranscriptPanelMissing()
    {
        // Build a layout that is missing the transcript panel entirely.
        var root = new ElementInfo { Id = 0x1000000Eu, Type = 3, Width = 490, Height = 100 };
        // No children → TranscriptPanelId and InputBarId are absent from the widget tree.

        var layout = LayoutImporter.Build(root, NoTex, null);
        var vm = new ChatVM(new ChatLog());
        var bus = new CaptureBus();

        var ctrl = ChatWindowController.Bind(root, layout, vm, bus, null, null, NoTex);

        Assert.Null(ctrl);
    }
}