using System;
using Paca.Mobile.Core;
using Xunit;

namespace Paca.Tests.Core;

public class ThumbnailScrubberPreviewGateTests
{
    [Fact]
    public void Gate241_ThumbnailScrubberPreview_CalculatesTimestamp_AndFormatsProperly()
    {
        Assert.Equal("00:45", ThumbnailScrubberPreview.FormatTimestamp(45.2));
        Assert.Equal("01:01:05", ThumbnailScrubberPreview.FormatTimestamp(3665.0));
        Assert.Equal("00:00", ThumbnailScrubberPreview.FormatTimestamp(0));
    }

    [Fact]
    public void Gate242_ThumbnailScrubberPreview_CalculatesThumbnailUrl_WithSeekQuery()
    {
        var preview = new ThumbnailScrubberPreview("media-123", totalDurationSec: 200.0);
        var url = preview.GetPreviewUrlForRatio(0.5); // 100s

        Assert.Contains("/api/library/media-123/thumb", url);
        Assert.Contains("t=100", url);
    }

    [Fact]
    public void Gate243_ThumbnailScrubberPreview_ClampsSeekPositionWithinBounds()
    {
        var preview = new ThumbnailScrubberPreview("media-999", totalDurationSec: 100.0);

        // Underflow clamp
        var underflowTime = preview.GetClampedSeekTime(-0.1);
        Assert.Equal(0.0, underflowTime);

        // Overflow clamp
        var overflowTime = preview.GetClampedSeekTime(1.5);
        Assert.Equal(100.0, overflowTime);
    }

    [Fact]
    public void Gate244_ThumbnailScrubberPreview_LruCache_EvictsOldestWhenLimitReached()
    {
        var cache = new ScrubberPreviewCache(capacity: 3);

        cache.Put("t=10", new byte[] { 1 });
        cache.Put("t=20", new byte[] { 2 });
        cache.Put("t=30", new byte[] { 3 });

        Assert.True(cache.TryGet("t=10", out _));
        Assert.True(cache.TryGet("t=20", out _));
        Assert.True(cache.TryGet("t=30", out _));

        // Add 4th item, oldest accessed was t=10 before t=20/t=30, now add t=40
        cache.Put("t=40", new byte[] { 4 });

        Assert.Equal(3, cache.Count);
        // t=40 is in cache
        Assert.True(cache.TryGet("t=40", out _));
    }
}