// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
#nullable disable
 
using System.Threading;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.CSharp.Extensions;
using Xunit;
 
namespace Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.Extensions
{
    public class SyntaxTreeExtensionsTests
    {
        private static void VerifyWholeLineIsActive(SyntaxTree tree, int lineNumber)
        {
            var line = tree.GetText().Lines[lineNumber];
            for (var pos = line.Start; pos < line.EndIncludingLineBreak; pos++)
            {
                Assert.False(tree.IsInInactiveRegion(pos, CancellationToken.None));
            }
        }
 
        private static void VerifyWholeLineIsInactive(SyntaxTree tree, int lineNumber)
        {
            var line = tree.GetText().Lines[lineNumber];
            for (var pos = line.Start; pos < line.EndIncludingLineBreak; pos++)
            {
                Assert.True(tree.IsInInactiveRegion(pos, CancellationToken.None));
            }
        }
 
        [Fact]
        public void SimpleInactive()
        {
            var code = @"#if false
This is inactive
#else
// This is active
#endif
";
            var tree = CSharpSyntaxTree.ParseText(code);
            VerifyWholeLineIsActive(tree, 0);
            VerifyWholeLineIsInactive(tree, 1);
            VerifyWholeLineIsActive(tree, 2);
            VerifyWholeLineIsActive(tree, 3);
            VerifyWholeLineIsActive(tree, 4);
        }
 
        [Fact]
        public void InactiveEof()
        {
            var code = @"#if false
This is inactive
";
            var tree = CSharpSyntaxTree.ParseText(code);
            VerifyWholeLineIsActive(tree, 0);
            VerifyWholeLineIsInactive(tree, 1);
        }
 
        [Fact]
        public void InactiveEof2()
        {
            var code = @"#if false
This is inactive
#endif
// This is active
";
 
            var tree = CSharpSyntaxTree.ParseText(code);
            VerifyWholeLineIsActive(tree, 0);
            VerifyWholeLineIsInactive(tree, 1);
            VerifyWholeLineIsActive(tree, 2);
            VerifyWholeLineIsActive(tree, 3);
        }
    }
}