// Copyright (c) Six Labors.
// Licensed under the Six Labors Split License.

using System.Collections.Generic;
using System.Numerics;

namespace SixLabors.ImageSharp.Drawing {
  /// <summary>
  /// A path that is always empty.
  /// </summary>
  public sealed class EmptyPath : IPath
  {
      private static readonly LinearGeometry EmptyGeometry = new(
          new LinearGeometryInfo
          {
              Bounds = RectangleF.Empty,
              ContourCount = 0,
              PointCount = 0,
              SegmentCount = 0,
              NonHorizontalSegmentCountPixelBoundary = 0,
              NonHorizontalSegmentCountPixelCenter = 0
          },
          [],
          []);

      private EmptyPath(PathTypes pathType) => this.PathType = pathType;

      /// <summary>
      /// Gets the closed path instance of the empty path
      /// </summary>
      public static EmptyPath ClosedPath { get; } = new(PathTypes.Closed);

      /// <summary>
      /// Gets the open path instance of the empty path
      /// </summary>
      public static EmptyPath OpenPath { get; } = new(PathTypes.Open);

      /// <inheritdoc />
      public PathTypes PathType { get; }

      /// <inheritdoc />
      public RectangleF Bounds => RectangleF.Empty;

      /// <inheritdoc />
      public IPath AsClosedPath() => ClosedPath;

      /// <inheritdoc />
      public IEnumerable<ISimplePath> Flatten() => [];

      /// <inheritdoc />
      public LinearGeometry ToLinearGeometry(Vector2 scale) => EmptyGeometry;

      /// <inheritdoc />
      public IPath Transform(Matrix4x4 matrix) => this;
  }
}