// Copyright (c) AlphaSierraPapa for the SharpDevelop Team
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy of this
// software and associated documentation files (the "Software"), to deal in the Software
// without restriction, including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
// to whom the Software is furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all copies or
// substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.

using System;
using System.Linq;
using ICSharpCode.NRefactory.Semantics;
using ICSharpCode.NRefactory.TypeSystem.Implementation;
using NUnit.Framework;

namespace ICSharpCode.NRefactory.CSharp.Resolver
{
	[TestFixture]
	public class LambdaTests : ResolverTestBase
	{
		[Test]
		public void SimpleLambdaTest()
		{
			string program = @"using System;
class TestClass {
	static void Main() {
		Test(i => Console.WriteLine(i));
	}
	public void Test(Action<int> ac) { ac(42); }
}";
			var lrr = Resolve<LocalResolveResult>(program.Replace("(i)", "($i$)"));
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
			
			lrr = Resolve<LocalResolveResult>(program.Replace("i =>", "$i$ =>"));
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaInConstructorTest()
		{
			string program = @"using System;
class TestClass {
	static void Main() {
		TestClass t = new TestClass(i => Console.WriteLine($i$));
	}
	public TestClass(Action<int> ac) { ac(42); }
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaInGenericConstructorTest()
		{
			string program = @"using System;
class TestClass {
	static void Main() {
		var t = new SomeClass<string>(i => Console.WriteLine($i$));
	}
}
class SomeClass<T> {
	public SomeClass(Action<T> ac) { }
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.String", lrr.Type.ReflectionName);
		}
		
		#region Lambda In Array Initializer
		[Test]
		public void LambdaInArrayInitializer1()
		{
			string program = @"using System;
class TestClass {
	static void Main() {
		Converter<int, string>[] arr = {
			i => $i$.ToString()
		};
	}
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaInArrayInitializer2()
		{
			string program = @"using System;
class TestClass {
	static void Main() {
		a = new Converter<int, string>[] {
			i => $i$.ToString()
		};
	}
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaInArrayInitializer3()
		{
			string program = @"using System;
class TestClass {
	Converter<int, string>[] field = new Converter<int, string>[] {
		i => $i$.ToString()
	};
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaInArrayInitializer4()
		{
			string program = @"using System;
class TestClass {
	Converter<int, string>[] field = {
		i => $i$.ToString()
	};
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaIn2DArrayInitializer()
		{
			string program = @"using System;
class TestClass {
	static void Main() {
		Converter<int, string>[,] arr = {
			{ i => $i$.ToString() }
		};
	}
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaInInferred2DArrayInitializer()
		{
			string program = @"using System;
class TestClass {
	static void Main() {
		var c = new [,] { { null, (Converter<int, string>)null }, { a => $a$.ToString(), b => b.ToString() }};
	}
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		#endregion
		
		#region Lambda In Collection Initializer
		[Test]
		public void LambdaInCollectionInitializer1()
		{
			string program = @"using System; using System.Collections.Generic;
class TestClass {
	static void Main() {
		a = new List<Converter<int, string>> {
			i => $i$.ToString()
		};
	}
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaInCollectionInitializer2()
		{
			string program = @"using System; using System.Collections.Generic;
class TestClass {
	static void Main() {
		a = new Dictionary<Func<char, string>, Converter<int, string>> {
			{ i => $i$.ToString(), i => i.ToString() }
		};
	}
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Char", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaInCollectionInitializer3()
		{
			string program = @"using System; using System.Collections.Generic;
class TestClass {
	static void Main() {
		a = new Dictionary<Func<char, string>, Converter<int, string>> {
			{ i => i.ToString(), $i$ => i.ToString() }
		};
	}
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		#endregion
		
		[Test]
		public void LambdaInObjectInitializerTest()
		{
			string program = @"using System;
class X {
	void SomeMethod() {
		Helper h = new Helper {
			F = i => $i$.ToString()
		};
	}
}
class Helper {
	public Converter<int, string> F;
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaExpressionInCastExpression()
		{
			string program = @"using System;
static class TestClass {
	static void Main(string[] args) {
		var f = (Func<int, string>) ( i => $i$ );
	}
	public delegate R Func<T, R>(T arg);
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaExpressionInDelegateCreateExpression()
		{
			string program = @"using System;
static class TestClass {
	static void Main(string[] args) {
		var f = new Func<int, string>( i => $i$ );
	}
	public delegate R Func<T, R>(T arg);
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaExpressionInReturnStatement()
		{
			string program = @"using System;
static class TestClass {
	static Converter<int, string> GetToString() {
		return i => $i$.ToString();
	}
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaExpressionInReturnStatementInStatementLambda()
		{
			string program = @"using System;
static class TestClass {
	static void SomeMethod() {
		Func<Func<string, string>> getStringTransformer = () => {
			return s => $s$.ToUpper();
		};
	}
	public delegate R Func<T, R>(T arg);
	public delegate R Func<R>();
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.String", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaExpressionInReturnStatementInAnonymousMethod()
		{
			string program = @"using System;
static class TestClass {
	static void SomeMethod() {
		Func<Func<string, string>> getStringTransformer = delegate {
			return s => $s$.ToUpper();
		};
	}
	public delegate R Func<T, R>(T arg);
	public delegate R Func<R>();
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.String", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void CurriedLambdaExpressionInCastExpression()
		{
			string program = @"using System;
static class TestClass {
	static void Main(string[] args) {
		var f = (Func<char, Func<string, int>>) ( a => b => 0 );
	}
	public delegate R Func<T, R>(T arg);
}";
			var lrr = Resolve<LocalResolveResult>(program.Replace("a =>", "$a$ =>"));
			Assert.AreEqual("System.Char", lrr.Type.ReflectionName);
			
			lrr = Resolve<LocalResolveResult>(program.Replace("b =>", "$b$ =>"));
			Assert.AreEqual("System.String", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaExpressionInVariableInitializer()
		{
			string program = @"using System;
static class TestClass {
	static void Main() {
		Func<int, string> f = $i$ => i.ToString();
	}
	public delegate R Func<T, R>(T arg);
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaExpressionInVariableAssignment()
		{
			string program = @"using System;
static class TestClass {
	static void Main() {
		Func<int, string> f;
 		f = $i$ => i.ToString();
	}
	public delegate R Func<T, R>(T arg);
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void LambdaInDelegateCall()
		{
			string program = @"using System;
class TestClass {
	static void Main() {
		Func<Func<int, string>, char> f;
		f($i$ => i.ToString());
	}
	public delegate R Func<T, R>(T arg);
}";
			var lrr = Resolve<LocalResolveResult>(program);
			Assert.AreEqual("System.Int32", lrr.Type.ReflectionName);
		}
		
		[Test]
		public void ConvertAllInGenericMethod()
		{
			string program = @"using System;
class TestClass {
	static void Method<T>(System.Collections.Generic.List<T> list) {
		$list.ConvertAll(x => (int)x)$;
	}
}";
			var rr = Resolve<CSharpInvocationResolveResult>(program);
			Assert.IsFalse(rr.IsError);
			SpecializedMethod m = (SpecializedMethod)rr.Member;
			Assert.AreEqual("System.Int32", m.TypeArguments[0].ReflectionName);
			Assert.AreEqual("System.Converter`2[[``0],[System.Int32]]", m.Parameters[0].Type.ReflectionName);
			
			var crr = (ConversionResolveResult)rr.Arguments[0];
			Assert.IsTrue(crr.Conversion.IsAnonymousFunctionConversion);
			Assert.AreEqual("System.Converter`2[[``0],[System.Int32]]", crr.Type.ReflectionName);
		}
		
		[Test]
		public void AnonymousMethodWithoutParameterList()
		{
			string program = @"using System;
class TestClass {
	event EventHandler Ev = $delegate {}$;
}";
			var rr = Resolve<LambdaResolveResult>(program);
			Assert.IsFalse(rr.IsError);
			Assert.IsFalse(rr.HasParameterList);
		}
		
		[Test]
		public void NonVoidMethodInActionLambdaIsValidConversion()
		{
			string program = @"using System;
class TestClass {
	void Run(Action a) { }
	int M() {
		Run(() => $M()$);
	}
}";
			var c = GetConversion(program);
			Assert.IsTrue(c.IsValid);
		}
		
		[Test]
		public void NonVoidMethodInImplicitlyTypedActionLambdaIsValidConversion()
		{
			string program = @"using System;
class TestClass {
	void Run(Action<string> a) { }
	int M() {
		Run(x => $M()$);
	}
}";
			var c = GetConversion(program);
			Assert.IsTrue(c.IsValid);
		}
		
		[Test]
		public void RaisePropertyChanged_WithExpressionLambda()
		{
			string program = @"using System;
using System.Linq.Expressions;
class Test {
	void RaisePropertyChanged<T>(Expression<Func<T>> propertyExpression) {}
	void RaisePropertyChanged(string propertyName) {}
	string MyProperty { get {} }
	void Test() {
		$RaisePropertyChanged(() => MyProperty)$;
	}
}";
			var rr = Resolve<CSharpInvocationResolveResult>(program);
			Assert.IsFalse(rr.IsError);
			Assert.AreEqual("propertyExpression", rr.Member.Parameters.Single().Name);
		}
		
		/* TODO write test for this
class A
{
    static void Foo(string x, Action<Action> y) { Console.WriteLine(1); }
    static void Foo(object x, Func<Func<int>, int> y) { Console.WriteLine(2); }

    static void Main()
    {
        Foo(null, x => x()); // Prints 1
        Foo(null, x => (x())); // Prints 2
    }
}
		 */
	}
}