using TinyTUI.Rendering;
using TinyTUI.Terminal.Images;
using TinyTUI.Tests.TestInfrastructure;
using TinyTUI.Text;

namespace TinyTUI.Tests.Rendering;

public sealed class DifferentialRendererTests
{
    private static readonly RenderPipelineOptions TestOptions = new()
    {
        ThrowOnWidthOverflow = true,
        UseSynchronizedOutput = false,
    };

    [Fact]
    public void FirstRenderCapturesVisibleViewportAndLineResets()
    {
        var output = new VirtualTerminalOutput(20, 3);
        var renderer = CreateRenderer(output);

        renderer.Render(["Line 0", "Line 1", "Line 2", "Line 3"], output.Size);

        Assert.Equal(1, renderer.FullRedrawCount);
        Assert.Equal(new RenderViewportState(1, 3, 4, 4), renderer.ViewportState);
        Assert.Contains("Line 1\e[0m\e]8;;\a", output.Buffer.ToString(), StringComparison.Ordinal);
        Assert.DoesNotContain("Line 0", output.Buffer.ToString(), StringComparison.Ordinal);
    }

    [Fact]
    public void DiffRenderOnlyMovesAndClearsChangedRows()
    {
        var output = new VirtualTerminalOutput(20, 4);
        var renderer = CreateRenderer(output);
        renderer.Render(["Header", "Working...", "Footer"], output.Size);
        output.ClearWrites();

        renderer.Render(["Header", "Working /", "Footer"], output.Size);

        Assert.Equal(1, renderer.DifferentialRedrawCount);
        Assert.Contains("\e[2;1H\e[2KWorking /", output.Buffer.ToString(), StringComparison.Ordinal);
        Assert.DoesNotContain("\e[1;1H\e[2KHeader", output.Buffer.ToString(), StringComparison.Ordinal);
    }

    [Fact]
    public void ResizeAndShrinkForceFullRedrawsToClearStaleRows()
    {
        var output = new VirtualTerminalOutput(20, 5);
        var renderer = CreateRenderer(output);
        renderer.Render(["Line 0", "Line 1", "Line 2", "Line 3"], output.Size);

        output.Resize(20, 6);
        output.ClearWrites();
        renderer.Render(["Line 0", "Line 1", "Line 2", "Line 3"], output.Size);
        Assert.Equal(2, renderer.FullRedrawCount);
        Assert.True(output.Contains("\e[2J\e[H"));

        output.ClearWrites();
        renderer.Render(["Line 0"], output.Size);
        Assert.Equal(3, renderer.FullRedrawCount);
        Assert.True(output.Contains("\e[2J\e[H"));
    }

    [Fact]
    public void CursorMarkerMovesHardwareCursorAndCanShowCursor()
    {
        var output = new VirtualTerminalOutput(20, 4);
        var renderer = new DifferentialRenderer(
            output,
            new TerminalTextMeasurer(),
            new RenderPipelineOptions
            {
                ThrowOnWidthOverflow = true,
                UseSynchronizedOutput = false,
                ShowHardwareCursor = true,
            });

        renderer.Render([$"ab{CursorMarker.Marker}cd"], output.Size);

        Assert.True(output.Contains("\e[1;3H"));
        Assert.True(output.Contains("\e[?25h"));
    }

    [Fact]
    public void ChangedKittyImageIsDeletedBeforeReplacementLine()
    {
        var output = new VirtualTerminalOutput(20, 4);
        var renderer = CreateRenderer(output);
        var kittyLine = "\e_Ga=T,f=100,q=2,C=1,c=1,r=1,i=42;AAAA\e\\";

        renderer.Render([kittyLine], output.Size);
        output.ClearWrites();
        renderer.Render(["changed"], output.Size);

        var writes = output.Buffer.ToString();
        var deleteIndex = writes.IndexOf(TerminalImageService.DeleteKittyImage(42), StringComparison.Ordinal);
        var changedIndex = writes.IndexOf("changed", StringComparison.Ordinal);
        Assert.True(deleteIndex >= 0);
        Assert.True(changedIndex >= 0);
        Assert.True(deleteIndex < changedIndex);
    }

    [Fact]
    public void LongITerm2ImageLineBypassesTextWidthOverflow()
    {
        var output = new VirtualTerminalOutput(20, 5);
        var renderer = CreateRenderer(output);
        var imageLine = $"Read image file \e]1337;File=inline=1:{new string('A', 200)}\a";

        // 图像协议本身可能很长 但渲染器应按图像行处理而不是按可见文本宽度报错
        renderer.Render([imageLine], output.Size);
        renderer.Render(["plain"], output.Size);

        Assert.Contains("plain", output.Buffer.ToString(), StringComparison.Ordinal);
    }

    private static DifferentialRenderer CreateRenderer(VirtualTerminalOutput output)
        => new(output, new TerminalTextMeasurer(), TestOptions);
}