// ****************************************************************
// This is free software licensed under the NUnit license. You
// may obtain a copy of the license as well as information regarding
// copyright ownership at http://nunit.org.
// ****************************************************************

using System;
using System.IO;
using System.ComponentModel;
using NUnit.Framework.Constraints;

namespace NUnit.Framework
{
	/// <summary>
	/// Summary description for FileAssert.
	/// </summary>
	public class FileAssert
	{
		#region Equals and ReferenceEquals

		/// <summary>
		/// The Equals method throws an AssertionException. This is done 
		/// to make sure there is no mistake by calling this function.
		/// </summary>
		/// <param name="a"></param>
		/// <param name="b"></param>
		[EditorBrowsable(EditorBrowsableState.Never)]
		public static new bool Equals(object a, object b)
		{
			throw new AssertionException("Assert.Equals should not be used for Assertions");
		}

		/// <summary>
		/// override the default ReferenceEquals to throw an AssertionException. This 
		/// implementation makes sure there is no mistake in calling this function 
		/// as part of Assert. 
		/// </summary>
		/// <param name="a"></param>
		/// <param name="b"></param>
		public static new void ReferenceEquals(object a, object b)
		{
			throw new AssertionException("Assert.ReferenceEquals should not be used for Assertions");
		}

		#endregion
				
		#region Constructor

		/// <summary>
		/// We don't actually want any instances of this object, but some people
		/// like to inherit from it to add other static methods. Hence, the
		/// protected constructor disallows any instances of this object. 
		/// </summary>
		protected FileAssert() {}

		#endregion

		#region AreEqual

		#region Streams
		
		/// <summary>
		/// Verifies that two Streams are equal.  Two Streams are considered
		/// equal if both are null, or if both have the same value byte for byte.
		/// If they are not equal an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The expected Stream</param>
		/// <param name="actual">The actual Stream</param>
		/// <param name="message">The message to display if Streams are not equal</param>
		/// <param name="args">Arguments to be used in formatting the message</param>
		static public void AreEqual(Stream expected, Stream actual, string message, params object[] args)
		{
			Assert.That( actual, new EqualConstraint( expected ), message, args );
		}

		/// <summary>
		/// Verifies that two Streams are equal.  Two Streams are considered
		/// equal if both are null, or if both have the same value byte for byte.
		/// If they are not equal an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The expected Stream</param>
		/// <param name="actual">The actual Stream</param>
		/// <param name="message">The message to display if objects are not equal</param>
		static public void AreEqual(Stream expected, Stream actual, string message) 
		{
			AreEqual(expected, actual, message, null);
		}

		/// <summary>
		/// Verifies that two Streams are equal.  Two Streams are considered
		/// equal if both are null, or if both have the same value byte for byte.
		/// If they are not equal an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The expected Stream</param>
		/// <param name="actual">The actual Stream</param>
		static public void AreEqual(Stream expected, Stream actual) 
		{
			AreEqual(expected, actual, string.Empty, null);
		}

		#endregion

		#region FileInfo
		/// <summary>
		/// Verifies that two files are equal.  Two files are considered
		/// equal if both are null, or if both have the same value byte for byte.
		/// If they are not equal an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">A file containing the value that is expected</param>
		/// <param name="actual">A file containing the actual value</param>
		/// <param name="message">The message to display if Streams are not equal</param>
		/// <param name="args">Arguments to be used in formatting the message</param>
		static public void AreEqual(FileInfo expected, FileInfo actual, string message, params object[] args)
		{
			using (FileStream exStream = expected.OpenRead())
			{
				using (FileStream acStream = actual.OpenRead())
				{
					AreEqual(exStream,acStream,message,args);
				}
			}
		}

		/// <summary>
		/// Verifies that two files are equal.  Two files are considered
		/// equal if both are null, or if both have the same value byte for byte.
		/// If they are not equal an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">A file containing the value that is expected</param>
		/// <param name="actual">A file containing the actual value</param>
		/// <param name="message">The message to display if objects are not equal</param>
		static public void AreEqual(FileInfo expected, FileInfo actual, string message) 
		{
			AreEqual(expected, actual, message, null);
		}

		/// <summary>
		/// Verifies that two files are equal.  Two files are considered
		/// equal if both are null, or if both have the same value byte for byte.
		/// If they are not equal an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">A file containing the value that is expected</param>
		/// <param name="actual">A file containing the actual value</param>
		static public void AreEqual(FileInfo expected, FileInfo actual) 
		{
			AreEqual(expected, actual, string.Empty, null);
		}

		#endregion

		#region String
		/// <summary>
		/// Verifies that two files are equal.  Two files are considered
		/// equal if both are null, or if both have the same value byte for byte.
		/// If they are not equal an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The path to a file containing the value that is expected</param>
		/// <param name="actual">The path to a file containing the actual value</param>
		/// <param name="message">The message to display if Streams are not equal</param>
		/// <param name="args">Arguments to be used in formatting the message</param>
		static public void AreEqual(string expected, string actual, string message, params object[] args)
		{
			using (FileStream exStream = File.OpenRead(expected))
			{
				using (FileStream acStream = File.OpenRead(actual))
				{
					AreEqual(exStream,acStream,message,args);
				}
			}
		}

		/// <summary>
		/// Verifies that two files are equal.  Two files are considered
		/// equal if both are null, or if both have the same value byte for byte.
		/// If they are not equal an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The path to a file containing the value that is expected</param>
		/// <param name="actual">The path to a file containing the actual value</param>
		/// <param name="message">The message to display if objects are not equal</param>
		static public void AreEqual(string expected, string actual, string message) 
		{
			AreEqual(expected, actual, message, null);
		}

		/// <summary>
		/// Verifies that two files are equal.  Two files are considered
		/// equal if both are null, or if both have the same value byte for byte.
		/// If they are not equal an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The path to a file containing the value that is expected</param>
		/// <param name="actual">The path to a file containing the actual value</param>
		static public void AreEqual(string expected, string actual) 
		{
			AreEqual(expected, actual, string.Empty, null);
		}

		#endregion

		#endregion

		#region AreNotEqual

		#region Streams
		/// <summary>
		/// Asserts that two Streams are not equal. If they are equal
		/// an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The expected Stream</param>
		/// <param name="actual">The actual Stream</param>
		/// <param name="message">The message to be displayed when the two Stream are the same.</param>
		/// <param name="args">Arguments to be used in formatting the message</param>
		static public void AreNotEqual( Stream expected, Stream actual, string message, params object[] args)
		{
			Assert.That( actual, new NotConstraint( new EqualConstraint( expected ) ), message, args );
		}

		/// <summary>
		/// Asserts that two Streams are not equal. If they are equal
		/// an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The expected Stream</param>
		/// <param name="actual">The actual Stream</param>
		/// <param name="message">The message to be displayed when the Streams are the same.</param>
		static public void AreNotEqual(Stream expected, Stream actual, string message) 
		{
			AreNotEqual(expected, actual, message, null);
		}
   
		/// <summary>
		/// Asserts that two Streams are not equal. If they are equal
		/// an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The expected Stream</param>
		/// <param name="actual">The actual Stream</param>
		static public void AreNotEqual(Stream expected, Stream actual) 
		{
			AreNotEqual(expected, actual, string.Empty, null);
		}
		#endregion
		
		#region FileInfo
		/// <summary>
		/// Asserts that two files are not equal. If they are equal
		/// an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">A file containing the value that is expected</param>
		/// <param name="actual">A file containing the actual value</param>
		/// <param name="message">The message to display if Streams are not equal</param>
		/// <param name="args">Arguments to be used in formatting the message</param>
		static public void AreNotEqual(FileInfo expected, FileInfo actual, string message, params object[] args)
		{
			using (FileStream exStream = expected.OpenRead())
			{
				using (FileStream acStream = actual.OpenRead())
				{
					AreNotEqual(exStream,acStream,message,args);
				}
			}
		}

		/// <summary>
		/// Asserts that two files are not equal. If they are equal
		/// an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">A file containing the value that is expected</param>
		/// <param name="actual">A file containing the actual value</param>
		/// <param name="message">The message to display if objects are not equal</param>
		static public void AreNotEqual(FileInfo expected, FileInfo actual, string message) 
		{
			AreNotEqual(expected, actual, message, null);
		}

		/// <summary>
		/// Asserts that two files are not equal. If they are equal
		/// an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">A file containing the value that is expected</param>
		/// <param name="actual">A file containing the actual value</param>
		static public void AreNotEqual(FileInfo expected, FileInfo actual) 
		{
			AreNotEqual(expected, actual, string.Empty, null);
		}

		#endregion
		
		#region String
		/// <summary>
		/// Asserts that two files are not equal. If they are equal
		/// an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The path to a file containing the value that is expected</param>
		/// <param name="actual">The path to a file containing the actual value</param>
		/// <param name="message">The message to display if Streams are not equal</param>
		/// <param name="args">Arguments to be used in formatting the message</param>
		static public void AreNotEqual(string expected, string actual, string message, params object[] args)
		{
			using (FileStream exStream = File.OpenRead(expected))
			{
				using (FileStream acStream = File.OpenRead(actual))
				{
					AreNotEqual(exStream,acStream,message,args);
				}
			}
		}

		/// <summary>
		/// Asserts that two files are not equal. If they are equal
		/// an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The path to a file containing the value that is expected</param>
		/// <param name="actual">The path to a file containing the actual value</param>
		/// <param name="message">The message to display if objects are not equal</param>
		static public void AreNotEqual(string expected, string actual, string message) 
		{
			AreNotEqual(expected, actual, message, null);
		}

		/// <summary>
		/// Asserts that two files are not equal. If they are equal
		/// an <see cref="AssertionException"/> is thrown.
		/// </summary>
		/// <param name="expected">The path to a file containing the value that is expected</param>
		/// <param name="actual">The path to a file containing the actual value</param>
		static public void AreNotEqual(string expected, string actual) 
		{
			AreNotEqual(expected, actual, string.Empty, null);
		}

		#endregion

		#endregion
	}
}