Monogame-Extended/tests/MonoGame.Extended.Tests/Tilemaps/TilemapObjects/TilemapPolygonObjectTests.cs

using System;
using System.Linq;
using Microsoft.Xna.Framework;
using MonoGame.Extended.Tilemaps;

namespace MonoGame.Extended.Tests;

public sealed class TilemapPolygonObjectTests
{
    [Fact]
    public void Constructor_SetsProperties()
    {
        var points = new Vector2[]
        {
            new(0, 0),
            new(10, 0),
            new(10, 10),
            new(0, 10)
        };

        var obj = new TilemapPolygonObject(1, new Vector2(5, 5), points);

        Assert.Equal(1, obj.Id);
        Assert.Equal(new Vector2(5, 5), obj.Position);
        Assert.Equal(points, obj.Points);
    }

    [Fact]
    public void WorldPoints_TransformsPointsToWorldCoordinates()
    {
        var points = new Vector2[]
        {
            new(0, 0),
            new(10, 0),
            new(10, 10)
        };
        var obj = new TilemapPolygonObject(1, new Vector2(5, 5), points);

        var worldPoints = obj.WorldPoints.ToList();

        Assert.Equal(3, worldPoints.Count);
        Assert.Equal(new Vector2(5, 5), worldPoints[0]);
        Assert.Equal(new Vector2(15, 5), worldPoints[1]);
        Assert.Equal(new Vector2(15, 15), worldPoints[2]);
    }

    [Fact]
    public void Bounds_CalculatesMinimumEnclosingRectangle()
    {
        var points = new Vector2[]
        {
            new(0, 0),
            new(20, 0),
            new(10, 15)
        };
        var obj = new TilemapPolygonObject(1, new Vector2(10, 10), points);

        var bounds = obj.Bounds;

        // World points: (10,10), (30,10), (20,25)
        // Min: (10,10), Max: (30,25)
        Assert.Equal(10, bounds.X);
        Assert.Equal(10, bounds.Y);
        Assert.Equal(20, bounds.Width);
        Assert.Equal(15, bounds.Height);
    }

    [Fact]
    public void Bounds_WithEmptyPoints_ReturnsZeroSizeAtPosition()
    {
        var obj = new TilemapPolygonObject(1, new Vector2(10, 20), Array.Empty<Vector2>());

        var bounds = obj.Bounds;

        Assert.Equal(10, bounds.X);
        Assert.Equal(20, bounds.Y);
        Assert.Equal(0, bounds.Width);
        Assert.Equal(0, bounds.Height);
    }

    [Fact]
    public void Points_CanBeModified()
    {
        var obj = new TilemapPolygonObject(1, new Vector2(0, 0), new Vector2[] { new(0, 0) });
        var newPoints = new Vector2[] { new(5, 5), new(10, 10) };

        obj.Points = newPoints;

        Assert.Equal(newPoints, obj.Points);
                // Act
    }
}