// ArraySegmentTest.cs - NUnit Test Cases for the System.ArraySegment class
//
// Ankit Jain  <jankit@novell.com>
// Raja R Harinath  <rharinath@novell.com>
// Jensen Somers <jensen.somers@gmail.com>
// Marek Safar (marek.safar@gmail.com)
// 
// Copyright (C) 2006 Novell, Inc (http://www.novell.com)
// Copyright (C) 2012 Xamarin, Inc (http://www.xamarin.com)
// 

using NUnit.Framework;
using System;
using System.Collections.Generic;

namespace MonoTests.System
{
	[TestFixture]
	public class ArraySegmentTest
	{
		[Test]
		public void CtorTest1 ()
		{
			byte[] b_arr = new byte[4096];
			Array arr;

			ArraySegment<byte> seg = new ArraySegment<byte> (b_arr, 0, b_arr.Length);
			Assert.AreEqual (seg.Count, b_arr.Length, "#1");
			Assert.AreEqual (seg.Offset, 0, "#2");

			arr = seg.Array;
			Assert.AreEqual (arr.Length, 4096, "#5");

			seg = new ArraySegment<byte> (b_arr, 100, b_arr.Length - 100);
			Assert.AreEqual (seg.Count, b_arr.Length - 100, "#3");
			Assert.AreEqual (seg.Offset, 100, "#4");

			arr = seg.Array;
			Assert.AreEqual (arr.Length, 4096, "#5");
		}

		[Test]
		public void CtorTest2 ()
		{
			byte[] b_arr = new byte[4096];
			ArraySegment<byte> seg = new ArraySegment<byte> (b_arr);
			Assert.AreEqual (seg.Count, b_arr.Length, "#6");
			Assert.AreEqual (seg.Offset, 0, "#7");

			Array arr = seg.Array;
			Assert.AreEqual (arr.Length, 4096, "#8");
		}

		[Test]
		public void CtorTest3 ()
		{
			EmptyArraySegTest (0);
			EmptyArraySegTest (10);
		}

		private void EmptyArraySegTest (int len)
		{
			byte[] b_arr = new byte[len];

			ArraySegment<byte> seg = new ArraySegment<byte> (b_arr, 0, b_arr.Length);

			Assert.AreEqual (seg.Count, b_arr.Length, "#1 [array len {0}] ", len);
			Assert.AreEqual (seg.Offset, 0, "#2 [array len {0}] ", len);
			Array arr = seg.Array;
			Assert.AreEqual (arr.Length, len, "#3 [array len {0}] ", len);

			seg = new ArraySegment<byte> (b_arr, b_arr.Length, 0);
			Assert.AreEqual (seg.Count, 0, "#4 [array len {0}] ", len);
			Assert.AreEqual (seg.Offset, b_arr.Length, "#5 [array len {0}] ", len);
			arr = seg.Array;
			Assert.AreEqual (arr.Length, len, "#6 [array len {0}] ", len);

			seg = new ArraySegment<byte> (b_arr);
			Assert.AreEqual (seg.Count, b_arr.Length, "#7 [array len {0}] ", len);
			Assert.AreEqual (seg.Offset, 0, "#8 [array len {0}] ", len);
			arr = seg.Array;
			Assert.AreEqual (arr.Length, len, "#9 [array len {0}] ", len);
		}

		[Test]
		[ExpectedException (typeof (ArgumentException))]
		public void CtorErrorTest ()
		{
			byte[] arr = new byte[4096];
			ArraySegment<byte> seg = new ArraySegment<byte> (arr, 1, arr.Length);
		}

		[Test]
		[ExpectedException (typeof (ArgumentException))]
		public void CtorErrorTest2 ()
		{
			byte[] arr = new byte[4096];
			ArraySegment<byte> seg = new ArraySegment<byte> (arr, 0, arr.Length + 2);
		}

		[Test]
		[ExpectedException (typeof (ArgumentOutOfRangeException))]
		public void CtorErrorTest3 ()
		{
			byte[] arr = new byte[4096];
			ArraySegment<byte> seg = new ArraySegment<byte> (arr, -1, arr.Length);
		}

		[Test]
		[ExpectedException (typeof (ArgumentOutOfRangeException))]
		public void CtorErrorTest4 ()
		{
			byte[] arr = new byte[4096];
			ArraySegment<byte> seg = new ArraySegment<byte> (arr, 2, -1);
		}

		[Test]
		[ExpectedException (typeof (ArgumentException))]
		public void CtorErrorTest5 ()
		{
			byte[] arr = new byte[4096];
			ArraySegment<byte> seg = new ArraySegment<byte> (arr, 0, arr.Length + 2);
		}

		[Test]
		[ExpectedException (typeof (ArgumentNullException))]
		public void CtorNullTest1 ()
		{
			ArraySegment<byte> seg = new ArraySegment<byte> (null, 0, 1);
		}

		[Test]
		[ExpectedException (typeof (ArgumentNullException))]
		public void CtorNullTest2 ()
		{
			ArraySegment<byte> seg = new ArraySegment<byte> (null);
		}

		[Test]
		public void TestArraySegmentEqual ()
		{
			string[] myArr_1 = { "The", "good" };
			string[] myArr_2 = { "The", "good" };

			ArraySegment<string> myArrSeg_1 = new ArraySegment<string> (myArr_1);
			ArraySegment<string> myArrSeg_2 = new ArraySegment<string> (myArr_2);

			// Should return true.
			Assert.AreEqual (myArrSeg_1.Equals (myArrSeg_1), true);

			// Should return false. Allthough the strings are the same.
			Assert.AreEqual (myArrSeg_1.Equals (myArrSeg_2), false);
			Assert.AreEqual (myArrSeg_1 == myArrSeg_2, false);

			// Should return true.
			Assert.AreEqual (myArrSeg_1 != myArrSeg_2, true);
		}

#if NET_4_5
		[Test]
		public void IList_NotSupported ()
		{
			var array = new long[] { 1, 2, 3, 4, 5, 6, -10 };

			IList<long> s = new ArraySegment<long> (array, 2, 3);

			try {
				s.Add (1);
				Assert.Fail ("#1");
			} catch (NotSupportedException) {
			}

			try {
				s.Clear ();
				Assert.Fail ("#2");
			} catch (NotSupportedException) {
			}

			try {
				s.Remove (3);
				Assert.Fail ("#3");
			} catch (NotSupportedException) {
			}

			try {
				s.RemoveAt (3);
				Assert.Fail ("#4");
			} catch (NotSupportedException) {
			}

			try {
				s.Insert (2, 3);
				Assert.Fail ("#5");
			} catch (NotSupportedException) {
			}
		}

		[Test]
		public void IList_GetEnumerator ()
		{
			var array = new long[] { 1, 2, 3, 4, 5, 6, -10 };

			IList<long> s = new ArraySegment<long> (array, 2, 3);

			long total = 0;
			int count = 0;
			foreach (var i in s) {
				count++;
				total += i;
			}

			Assert.AreEqual (3, count, "#1");
			Assert.AreEqual (12, total, "#2");
		}

		[Test]
		public void IList_IndexOf ()
		{
			var array = new long[] { 1, 2, 3, 4, 5, 6, -10 };

			IList<long> s = new ArraySegment<long> (array, 2, 3);
			Assert.AreEqual (-1, s.IndexOf (2), "#1");
			Assert.AreEqual (1, s.IndexOf (4), "#2");
		}

		[Test]
		public void IList_Contains ()
		{
			var array = new long[] { 1, 2, 3, 4, 5, 6, -10 };

			IList<long> s = new ArraySegment<long> (array, 2, 3);
			Assert.IsFalse (s.Contains (2), "#1");
			Assert.IsTrue (s.Contains (4), "#2");
		}

		[Test]
		public void IList_CopyTo ()
		{
			var array = new long[] { 1, 2, 3, 4, 5, 6, -10 };

			IList<long> s = new ArraySegment<long> (array, 2, 3);
			long[] target = new long[s.Count];
			s.CopyTo (target, 0);

			Assert.AreEqual (3, target[0], "#1");
			Assert.AreEqual (4, target[1], "#2");
		}

		[Test]
		public void IList_Indexer ()
		{
			var array = new long[] { 1, 2, 3, 4, 5, 6, -10 };

			IList<long> s = new ArraySegment<long> (array, 2, 3);
			Assert.AreEqual (3, s[0], "#1");
			Assert.AreEqual (4, s[1], "#2");

			// LAMESPEC: I have not idea why is this allowed on ReadOnly array
			Assert.IsTrue (s.IsReadOnly, "#3");
			s[1] = -3;
			Assert.AreEqual (-3, s[1], "#2a");
		}

		[Test]
		[ExpectedException (typeof (ArgumentOutOfRangeException))]
		public void IList_IndexerErrorTest1 ()
		{
			byte[] arr = new byte[4];
			IList<byte> seg = new ArraySegment<byte> (arr, 1, 2);
			seg[-1] = 3;
		}

		[Test]
		[ExpectedException (typeof (ArgumentOutOfRangeException))]
		public void IList_IndexerErrorTest2 ()
		{
			byte[] arr = new byte[4];
			IList<byte> seg = new ArraySegment<byte> (arr);
			seg[4] = 3;
		}
#endif
	}
}