using System;
using Paca.Core;
using Xunit;

namespace Paca.Tests.Core;

public class VideoSpriteSheetGeneratorGateTests
{
    [Fact]
    public void Gate325_VideoSpriteSheetGenerator_ConfigComputesDimensions_Accurately()
    {
        var config = new SpriteSheetConfig(Columns: 5, Rows: 5, ThumbWidth: 160, ThumbHeight: 90, IntervalSec: 5);

        Assert.Equal(25, config.TotalTilesPerSheet);
        Assert.Equal(800, config.SheetWidth);  // 5 * 160
        Assert.Equal(450, config.SheetHeight); // 5 * 90
    }

    [Fact]
    public void Gate326_VideoSpriteSheetGenerator_BuildsFfmpegFilterArgs_Correctly()
    {
        var config = new SpriteSheetConfig(5, 5, 160, 90, 10);
        var cmd = VideoSpriteSheetGenerator.BuildFfmpegSpriteCommandLine("C:\\vid.mp4", "C:\\sprite.jpg", config);

        Assert.Contains("-i \"C:\\vid.mp4\"", cmd);
        Assert.Contains("-vf \"fps=1/10,scale=160:90,tile=5x5\"", cmd);
        Assert.Contains("-frames:v 1", cmd);
        Assert.EndsWith("\"C:\\sprite.jpg\" -y", cmd);
    }

    [Fact]
    public void Gate327_VideoSpriteSheetGenerator_GeneratesValidWebVttHeaderAndTimestamps()
    {
        var config = new SpriteSheetConfig(5, 5, 160, 90, 5);
        var vtt = VideoSpriteSheetGenerator.GenerateVttMapping("sprite.jpg", totalDurationSec: 25.0, config);

        Assert.StartsWith("WEBVTT", vtt.TrimStart());
        Assert.Contains("00:00:00.000 --> 00:00:05.000", vtt);
        Assert.Contains("00:00:05.000 --> 00:00:10.000", vtt);
        Assert.Contains("00:00:20.000 --> 00:00:25.000", vtt);
    }

    [Fact]
    public void Gate328_VideoSpriteSheetGenerator_CalculatesGridCoordinatesAndLineBreaks()
    {
        var config = new SpriteSheetConfig(Columns: 3, Rows: 3, ThumbWidth: 100, ThumbHeight: 50, IntervalSec: 1);
        var vtt = VideoSpriteSheetGenerator.GenerateVttMapping("sheet.jpg", totalDurationSec: 5.0, config);

        // Tile 0: row 0, col 0 -> 0,0,100,50
        Assert.Contains("sheet.jpg#xywh=0,0,100,50", vtt);
        // Tile 1: row 0, col 1 -> 100,0,100,50
        Assert.Contains("sheet.jpg#xywh=100,0,100,50", vtt);
        // Tile 2: row 0, col 2 -> 200,0,100,50
        Assert.Contains("sheet.jpg#xywh=200,0,100,50", vtt);
        // Tile 3: row 1, col 0 -> 0,50,100,50 (wrapped down to row 1)
        Assert.Contains("sheet.jpg#xywh=0,50,100,50", vtt);
    }
}