using System.Drawing;
using Microsoft.VisualStudio.TestTools.UnitTesting;

namespace Sacs.UnitTests.Net.Standard.Base.Generic
{
	[TestClass]
	public class ObjectReferences_Tester
	{
		//-------------------------------------------------------------------
		[TestMethod]
		public void ObjectReferences_ChangeValuesOnReferencedObject ()
		{
			// size2 starts as a reference to size1.
			Size size1 = new Size(10, 20);
			Size size2 = size1;
			Size size3 = new Size(10, 20);
			Assert.AreEqual(size1, size2);
			Assert.AreEqual(size1, size3);
			Assert.AreEqual(size2, size3);
			// Change size1 values - doesn't change size2.
			size1.Width = 100;
			size1.Height = 200;
			Assert.AreNotEqual(size1, size2);
			Assert.AreNotEqual(size1, size3);
			Assert.AreEqual(size2, size3);
		}
		[TestMethod]
		public void ObjectReferences_ChangeValuesOnObjectReference ()
		{
			// size2 starts as a reference to size1.
			Size size1 = new Size(10, 20);
			Size size2 = size1;
			Size size3 = new Size(10, 20);
			Assert.AreEqual(size1, size2);
			Assert.AreEqual(size1, size3);
			Assert.AreEqual(size2, size3);
			// Change size2 values - doesn't change size1.
			size2.Width = 100;
			size2.Height = 200;
			Assert.AreNotEqual(size1, size2);
			Assert.AreEqual(size1, size3);
			Assert.AreNotEqual(size2, size3);
		}
		//-------------------------------------------------------------------
		// Modify class value.
		class TestData
		{
			public int a = 0;
			public int B { get; set; }
			public Size size1 = new Size(10,20);
			public Size Size2 { get; set; } = new Size(30, 40);
		}
		[TestMethod]
		public void ObjectReferences_ChangeClassValues ()
		{
			TestData td1 = new TestData();
			TestData td2 = td1;
			Assert.AreEqual(td1, td2);
			td1.a++;  // td2 is still a reference to td1 with the same values.
			Assert.AreEqual(td1, td2);
			Assert.AreEqual(td1.a, td2.a);
			Assert.AreEqual(td1.B, td2.B);
			Assert.AreEqual(td1.size1, td2.size1);
			Assert.AreEqual(td1.Size2, td2.Size2);
			td1.B++;  // td2 is still a reference to td1 with the same values.
			Assert.AreEqual(td1, td2);
			Assert.AreEqual(td1.a, td2.a);
			Assert.AreEqual(td1.B, td2.B);
			Assert.AreEqual(td1.size1, td2.size1);
			Assert.AreEqual(td1.Size2, td2.Size2);
			td1.size1.Width += 10;  // td2 is still a reference to td1 with the same values.
			Assert.AreEqual(td1, td2);
			Assert.AreEqual(td1.a, td2.a);
			Assert.AreEqual(td1.B, td2.B);
			Assert.AreEqual(td1.size1, td2.size1);
			Assert.AreEqual(td1.Size2, td2.Size2);
			td1.Size2 = new Size(td1.Size2.Width, td1.Size2.Height + 10);  // td2 is still a reference to td1 with the same values.
			Assert.AreEqual(td1, td2);
			Assert.AreEqual(td1.a, td2.a);
			Assert.AreEqual(td1.B, td2.B);
			Assert.AreEqual(td1.size1, td2.size1);
			Assert.AreEqual(td1.Size2, td2.Size2);
		}
		//-------------------------------------------------------------------
	}
}