Dalamud/Dalamud/Interface/Internal/Windows/IMEWindow.cs

using System.Numerics;

using Dalamud.Game.ClientState.Keys;
using Dalamud.Game.Gui.Internal;
using Dalamud.Interface.Windowing;
using ImGuiNET;

namespace Dalamud.Interface.Internal.Windows;

/// <summary>
/// A window for displaying IME details.
/// </summary>
internal unsafe class ImeWindow : Window
{
    private const int ImePageSize = 9;

    /// <summary>
    /// Initializes a new instance of the <see cref="ImeWindow"/> class.
    /// </summary>
    public ImeWindow()
        : base("Dalamud IME", ImGuiWindowFlags.NoTitleBar | ImGuiWindowFlags.NoFocusOnAppearing | ImGuiWindowFlags.AlwaysAutoResize | ImGuiWindowFlags.NoBackground)
    {
        this.Size = new Vector2(100, 200);
        this.SizeCondition = ImGuiCond.FirstUseEver;

        this.RespectCloseHotkey = false;
    }

    /// <inheritdoc/>
    public override void Draw()
    {
        if (this.IsOpen && Service<KeyState>.Get()[VirtualKey.SHIFT]) Service<DalamudInterface>.Get().CloseImeWindow();
        var ime = Service<DalamudIME>.GetNullable();

        if (ime == null || !ime.IsEnabled)
        {
            ImGui.Text("IME is unavailable.");
            return;
        }

        // ImGui.Text($"{ime.GetCursorPos()}");
        // ImGui.Text($"{ImGui.GetWindowViewport().WorkSize}");
    }

    /// <inheritdoc/>
    public override void PostDraw()
    {
        if (this.IsOpen && Service<KeyState>.Get()[VirtualKey.SHIFT]) Service<DalamudInterface>.Get().CloseImeWindow();
        var ime = Service<DalamudIME>.GetNullable();

        if (ime == null || !ime.IsEnabled)
            return;

        var maxTextWidth = 0f;
        var textHeight = ImGui.CalcTextSize(ime.ImmComp).Y;

        var native = ime.ImmCandNative;
        var totalIndex = native.Selection + 1;
        var totalSize = native.Count;

        var pageStart = native.PageStart;
        var pageIndex = (pageStart / ImePageSize) + 1;
        var pageCount = (totalSize / ImePageSize) + 1;
        var pageInfo = $"{totalIndex}/{totalSize} ({pageIndex}/{pageCount})";

        // Calc the window size
        for (var i = 0; i < ime.ImmCand.Count; i++)
        {
            var textSize = ImGui.CalcTextSize($"{i + 1}. {ime.ImmCand[i]}");
            maxTextWidth = maxTextWidth > textSize.X ? maxTextWidth : textSize.X;
        }

        maxTextWidth = maxTextWidth > ImGui.CalcTextSize(pageInfo).X ? maxTextWidth : ImGui.CalcTextSize(pageInfo).X;
        maxTextWidth = maxTextWidth > ImGui.CalcTextSize(ime.ImmComp).X ? maxTextWidth : ImGui.CalcTextSize(ime.ImmComp).X;

        var imeWindowWidth = maxTextWidth + (2 * ImGui.GetStyle().WindowPadding.X);
        var imeWindowHeight = (textHeight * (ime.ImmCand.Count + 2)) + (5 * (ime.ImmCand.Count - 1)) + (2 * ImGui.GetStyle().WindowPadding.Y);

        // Calc the window pos
        var cursorPos = ime.GetCursorPos();
        var imeWindowMinPos = new Vector2(cursorPos.X, cursorPos.Y);
        var imeWindowMaxPos = new Vector2(imeWindowMinPos.X + imeWindowWidth, imeWindowMinPos.Y + imeWindowHeight);
        var gameWindowSize = ImGui.GetWindowViewport().WorkSize;

        var offset = new Vector2(
            imeWindowMaxPos.X - gameWindowSize.X > 0 ? imeWindowMaxPos.X - gameWindowSize.X : 0,
            imeWindowMaxPos.Y - gameWindowSize.Y > 0 ? imeWindowMaxPos.Y - gameWindowSize.Y : 0);
        imeWindowMinPos -= offset;
        imeWindowMaxPos -= offset;

        var nextDrawPosY = imeWindowMinPos.Y;
        var drawAreaPosX = imeWindowMinPos.X + ImGui.GetStyle().WindowPadding.X;

        // Draw the ime window
        var drawList = ImGui.GetForegroundDrawList();
        // Draw the background rect
        drawList.AddRectFilled(imeWindowMinPos, imeWindowMaxPos, ImGui.GetColorU32(ImGuiCol.WindowBg), ImGui.GetStyle().WindowRounding);
        // Add component text
        drawList.AddText(new Vector2(drawAreaPosX, nextDrawPosY), ImGui.GetColorU32(ImGuiCol.Text), ime.ImmComp);
        nextDrawPosY += textHeight + ImGui.GetStyle().ItemSpacing.Y;
        // Add separator
        drawList.AddLine(new Vector2(drawAreaPosX, nextDrawPosY), new Vector2(drawAreaPosX + maxTextWidth, nextDrawPosY), ImGui.GetColorU32(ImGuiCol.Separator));
        // Add candidate words
        for (var i = 0; i < ime.ImmCand.Count; i++)
        {
            var selected = i == (native.Selection % ImePageSize);
            var color = ImGui.GetColorU32(ImGuiCol.Text);
            if (selected)
                color = ImGui.GetColorU32(ImGuiCol.NavHighlight);

            drawList.AddText(new Vector2(drawAreaPosX, nextDrawPosY), color, $"{i + 1}. {ime.ImmCand[i]}");
            nextDrawPosY += textHeight + ImGui.GetStyle().ItemSpacing.Y;
        }

        // Add separator
        drawList.AddLine(new Vector2(drawAreaPosX, nextDrawPosY), new Vector2(drawAreaPosX + maxTextWidth, nextDrawPosY), ImGui.GetColorU32(ImGuiCol.Separator));
        // Add pages infomation
        drawList.AddText(new Vector2(drawAreaPosX, nextDrawPosY), ImGui.GetColorU32(ImGuiCol.Text), pageInfo);
    }
}