using ChunkyImageLib.DataHolders;
using SkiaSharp;

namespace ChunkyImageLib.Operations;

internal class ClearRegionOperation : IDrawOperation
{
    Vector2i pos;
    Vector2i size;

    public bool IgnoreEmptyChunks => true;

    public ClearRegionOperation(Vector2i pos, Vector2i size)
    {
        this.pos = pos;
        this.size = size;
    }

    public void DrawOnChunk(Chunk chunk, Vector2i chunkPos)
    {
        Vector2i convPos = OperationHelper.ConvertForResolution(pos, chunk.Resolution);
        Vector2i convSize = OperationHelper.ConvertForResolution(size, chunk.Resolution);

        chunk.Surface.SkiaSurface.Canvas.Save();
        chunk.Surface.SkiaSurface.Canvas.ClipRect(SKRect.Create(convPos - chunkPos.Multiply(chunk.PixelSize), convSize));
        chunk.Surface.SkiaSurface.Canvas.Clear();
        chunk.Surface.SkiaSurface.Canvas.Restore();
    }

    public HashSet<Vector2i> FindAffectedChunks()
    {
        return OperationHelper.FindChunksFullyInsideRectangle(pos, size, ChunkPool.FullChunkSize);
    }
    public void Dispose() { }
}