// <copyright file="SizeTests.cs" company="James Jackson-South">
// Copyright (c) James Jackson-South and contributors.
// Licensed under the Apache License, Version 2.0.
// </copyright>

namespace ImageSharp.Tests
{
    using System;
    using System.Globalization;
    using System.Reflection;
    using Xunit;

    public class SizeFTests
    {
        [Fact]
        public void DefaultConstructorTest()
        {
            Assert.Equal(SizeF.Empty, new SizeF());
        }

        [Theory]
        [InlineData(float.MaxValue, float.MinValue)]
        [InlineData(float.MinValue, float.MinValue)]
        [InlineData(float.MaxValue, float.MaxValue)]
        [InlineData(0, 0)]
        public void NonDefaultConstructorAndDimensionsTest(float width, float height)
        {
            var s1 = new SizeF(width, height);
            var p1 = new PointF(width, height);
            var s2 = new SizeF(s1);

            Assert.Equal(s1, s2);
            Assert.Equal(s1, new SizeF(p1));
            Assert.Equal(s2, new SizeF(p1));

            Assert.Equal(width, s1.Width);
            Assert.Equal(height, s1.Height);

            s1.Width = 10;
            Assert.Equal(10, s1.Width);

            s1.Height = -10.123f;
            Assert.Equal(-10.123, s1.Height, 3);
        }

        [Fact]
        public void IsEmptyDefaultsTest()
        {
            Assert.True(SizeF.Empty.IsEmpty);
            Assert.True(new SizeF().IsEmpty);
            Assert.True(new SizeF(0, 0).IsEmpty);
        }

        [Theory]
        [InlineData(float.MaxValue, float.MinValue)]
        [InlineData(float.MinValue, float.MinValue)]
        [InlineData(float.MaxValue, float.MaxValue)]
        public void IsEmptyRandomTest(float width, float height)
        {
            Assert.False(new SizeF(width, height).IsEmpty);
        }

        [Theory]
        [InlineData(float.MaxValue, float.MinValue)]
        [InlineData(float.MinValue, float.MinValue)]
        [InlineData(float.MaxValue, float.MaxValue)]
        [InlineData(0, 0)]
        public void ArithmeticTest(float width, float height)
        {
            var s1 = new SizeF(width, height);
            var s2 = new SizeF(height, width);
            var addExpected = new SizeF(width + height, width + height);
            var subExpected = new SizeF(width - height, height - width);

            Assert.Equal(addExpected, s1 + s2);
            Assert.Equal(addExpected, SizeF.Add(s1, s2));

            Assert.Equal(subExpected, s1 - s2);
            Assert.Equal(subExpected, SizeF.Subtract(s1, s2));
        }

        [Theory]
        [InlineData(float.MaxValue, float.MinValue)]
        [InlineData(float.MinValue, float.MinValue)]
        [InlineData(float.MaxValue, float.MaxValue)]
        [InlineData(0, 0)]
        public void EqualityTest(float width, float height)
        {
            var sLeft = new SizeF(width, height);
            var sRight = new SizeF(height, width);

            if (width == height)
            {
                Assert.True(sLeft == sRight);
                Assert.False(sLeft != sRight);
                Assert.True(sLeft.Equals(sRight));
                Assert.True(sLeft.Equals((object)sRight));
                Assert.Equal(sLeft.GetHashCode(), sRight.GetHashCode());
                return;
            }

            Assert.True(sLeft != sRight);
            Assert.False(sLeft == sRight);
            Assert.False(sLeft.Equals(sRight));
            Assert.False(sLeft.Equals((object)sRight));
        }

        [Fact]
        public static void EqualityTest_NotSizeF()
        {
            var size = new SizeF(0, 0);
            Assert.False(size.Equals(null));
            Assert.False(size.Equals(0));

            // If SizeF implements IEquatable<SizeF> (e.g in .NET Core), then classes that are implicitly
            // convertible to SizeF can potentially be equal.
            // See https://github.com/dotnet/corefx/issues/5255.
            bool expectsImplicitCastToSizeF = typeof(IEquatable<SizeF>).IsAssignableFrom(size.GetType());
            Assert.Equal(expectsImplicitCastToSizeF, size.Equals(new Size(0, 0)));

            Assert.False(size.Equals((object)new Size(0, 0))); // No implicit cast
        }

        [Fact]
        public static void GetHashCodeTest()
        {
            var size = new SizeF(10, 10);
            Assert.Equal(size.GetHashCode(), new SizeF(10, 10).GetHashCode());
            Assert.NotEqual(size.GetHashCode(), new SizeF(20, 10).GetHashCode());
            Assert.NotEqual(size.GetHashCode(), new SizeF(10, 20).GetHashCode());
        }

        [Theory]
        [InlineData(float.MaxValue, float.MinValue)]
        [InlineData(float.MinValue, float.MinValue)]
        [InlineData(float.MaxValue, float.MaxValue)]
        [InlineData(0, 0)]
        public void ConversionTest(float width, float height)
        {
            var s1 = new SizeF(width, height);
            var p1 = (PointF)s1;
            var s2 = new Size(unchecked((int)width), unchecked((int)height));

            Assert.Equal(new PointF(width, height), p1);
            Assert.Equal(p1, (PointF)s1);
            Assert.Equal(s2, (Size)s1);
        }

        [Fact]
        public void ToStringTest()
        {
            var sz = new SizeF(10, 5);
            Assert.Equal(string.Format(CultureInfo.CurrentCulture, "SizeF [ Width={0}, Height={1} ]", sz.Width, sz.Height), sz.ToString());
        }

        [Fact]
        public void ToStringTestEmpty()
        {
            var sz = new SizeF(0, 0);
            Assert.Equal("SizeF [ Empty ]", sz.ToString());
        }
    }
}