// 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.
 
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.Test.Utilities;
using Roslyn.Test.Utilities;
using Xunit;
 
namespace Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.Recommendations;
 
[Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
public sealed class NullKeywordRecommenderTests : KeywordRecommenderTests
{
    [Fact]
    public async Task TestAtRoot_Interactive()
    {
        await VerifyKeywordAsync(SourceCodeKind.Script,
@"$$");
    }
 
    [Fact]
    public async Task TestAfterClass_Interactive()
    {
        await VerifyKeywordAsync(SourceCodeKind.Script,
            """
            class C { }
            $$
            """);
    }
 
    [Fact]
    public async Task TestAfterGlobalStatement()
    {
        await VerifyKeywordAsync(
            """
            System.Console.WriteLine();
            $$
            """);
    }
 
    [Fact]
    public async Task TestAfterGlobalVariableDeclaration_Interactive()
    {
        await VerifyKeywordAsync(SourceCodeKind.Script,
            """
            int i = 0;
            $$
            """);
    }
 
    [Fact]
    public async Task TestNotInUsingAlias()
    {
        await VerifyAbsenceAsync(
@"using Goo = $$");
    }
 
    [Fact]
    public async Task TestNotInGlobalUsingAlias()
    {
        await VerifyAbsenceAsync(
@"global using Goo = $$");
    }
 
    [Fact]
    public async Task TestInEmptyStatement()
    {
        await VerifyKeywordAsync(AddInsideMethod(
@"$$"));
    }
 
    [Fact]
    public async Task TestInExpression()
    {
        await VerifyKeywordAsync(AddInsideMethod(
@"var q = $$"));
    }
 
    [Fact]
    public async Task TestNotInPPIf()
    {
        await VerifyAbsenceAsync(
@"#if $$");
    }
 
    [Fact]
    public async Task TestNotInPPIf_Or()
    {
        await VerifyAbsenceAsync(
@"#if a || $$");
    }
 
    [Fact]
    public async Task TestNotInPPIf_And()
    {
        await VerifyAbsenceAsync(
@"#if a && $$");
    }
 
    [Fact]
    public async Task TestNotInPPIf_Not()
    {
        await VerifyAbsenceAsync(
@"#if ! $$");
    }
 
    [Fact]
    public async Task TestNotInPPIf_Paren()
    {
        await VerifyAbsenceAsync(
@"#if ( $$");
    }
 
    [Fact]
    public async Task TestNotInPPIf_Equals()
    {
        await VerifyAbsenceAsync(
@"#if a == $$");
    }
 
    [Fact]
    public async Task TestNotInPPIf_NotEquals()
    {
        await VerifyAbsenceAsync(
@"#if a != $$");
    }
 
    [Fact]
    public async Task TestNotInPPElIf()
    {
        await VerifyAbsenceAsync(
            """
            #if true
            #elif $$
            """);
    }
 
    [Fact]
    public async Task TestNotInPPelIf_Or()
    {
        await VerifyAbsenceAsync(
            """
            #if true
            #elif a || $$
            """);
    }
 
    [Fact]
    public async Task TestNotInPPElIf_And()
    {
        await VerifyAbsenceAsync(
            """
            #if true
            #elif a && $$
            """);
    }
 
    [Fact]
    public async Task TestNotInPPElIf_Not()
    {
        await VerifyAbsenceAsync(
            """
            #if true
            #elif ! $$
            """);
    }
 
    [Fact]
    public async Task TestNotInPPElIf_Paren()
    {
        await VerifyAbsenceAsync(
            """
            #if true
            #elif ( $$
            """);
    }
 
    [Fact]
    public async Task TestNotInPPElIf_Equals()
    {
        await VerifyAbsenceAsync(
            """
            #if true
            #elif a == $$
            """);
    }
 
    [Fact]
    public async Task TestNotInPPElIf_NotEquals()
    {
        await VerifyAbsenceAsync(
            """
            #if true
            #elif a != $$
            """);
    }
 
    [Fact]
    public async Task TestNotAfterUnaryOperator()
    {
        await VerifyAbsenceAsync(
            """
            class C {
               public static bool operator $$
            """);
    }
 
    [Fact]
    public async Task TestNotAfterImplicitOperator()
    {
        await VerifyAbsenceAsync(
            """
            class C {
               public static implicit operator $$
            """);
    }
 
    [Fact]
    public async Task TestNotAfterExplicitOperator()
    {
        await VerifyAbsenceAsync(
            """
            class C {
               public static implicit operator $$
            """);
    }
 
    [Fact]
    public async Task TestAfterCastInField()
    {
        await VerifyKeywordAsync(
            """
            class C {
               public static readonly ImmutableList<T> Empty = new ImmutableList<T>((Segment)$$
            """);
    }
 
    [Fact]
    public async Task TestInTernary()
    {
        await VerifyKeywordAsync(AddInsideMethod(
            """
            SyntaxKind kind = caseOrDefaultKeywordOpt == $$ ? SyntaxKind.GotoStatement :
                            caseOrDefaultKeyword.Kind == SyntaxKind.CaseKeyword ? SyntaxKind.GotoCaseStatement : SyntaxKind.GotoDefaultStatement;
            """));
    }
 
    [Fact]
    public async Task TestInForMiddle()
    {
        await VerifyKeywordAsync(AddInsideMethod(
@"for (int i = 0; $$"));
    }
 
    [Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/538804")]
    public async Task TestNotInTypeOf()
    {
        await VerifyAbsenceAsync(AddInsideMethod(
@"typeof($$"));
    }
 
    [Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/538804")]
    public async Task TestNotInDefault()
    {
        await VerifyAbsenceAsync(AddInsideMethod(
@"default($$"));
    }
 
    [Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/538804")]
    public async Task TestNotInSizeOf()
    {
        await VerifyAbsenceAsync(AddInsideMethod(
@"sizeof($$"));
    }
 
    [Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/541670")]
    public async Task TestInReferenceSwitch()
    {
        await VerifyKeywordAsync(AddInsideMethod(
            """
            switch ("goo")
                    {
                        case $$
                    }
            """));
    }
 
    [Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/543766")]
    public async Task TestNotInDefaultParameterValue()
    {
        await VerifyKeywordAsync(
@"class C { void Goo(string[] args = $$");
    }
 
    [Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/544219")]
    public async Task TestNotInObjectInitializerMemberContext()
    {
        await VerifyAbsenceAsync("""
            class C
            {
                public int x, y;
                void M()
                {
                    var c = new C { x = 2, y = 3, $$
            """);
    }
 
    [Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/546938")]
    public async Task TestNotInCrefContext()
    {
        await VerifyAbsenceAsync("""
            class Program
            {
                /// <see cref="$$">
                static void Main(string[] args)
                {
 
                }
            }
            """);
    }
 
    [Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/546955")]
    public async Task TestInCrefContextNotAfterDot()
    {
        await VerifyAbsenceAsync("""
            /// <see cref="System.$$" />
            class C { }
            """);
    }
 
    [Fact]
    public async Task TestAfterIs()
        => await VerifyKeywordAsync(AddInsideMethod(@"if (x is $$"));
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/25293")]
    public async Task TestAfterIs_BeforeExpression()
    {
        await VerifyKeywordAsync(AddInsideMethod("""
            int x;
            int y = x is $$ Method();
            """));
    }
 
    [Fact]
    public async Task TestAfterLambdaOpenParen()
    {
        await VerifyKeywordAsync(
@"var lam = ($$");
    }
 
    [Fact]
    public async Task TestAfterLambdaComma()
    {
        await VerifyKeywordAsync(
@"var lam = (int i, $$");
    }
 
    [Fact]
    public async Task TestLambdaDefaultParameterValue()
    {
        await VerifyKeywordAsync(
@"var lam = (int i = $$");
    }
 
    #region Collection expressions
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70677")]
    public async Task TestInCollectionExpressions_BeforeFirstElementToVar()
    {
        await VerifyKeywordAsync(AddInsideMethod(
            """
            var x = [$$
            """));
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70677")]
    public async Task TestInCollectionExpressions_BeforeFirstElementToReturn()
    {
        await VerifyKeywordAsync(
            """
            class C
            {
                IEnumerable<string> M() => [$$
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70677")]
    public async Task TestInCollectionExpressions_AfterFirstElementToVar()
    {
        await VerifyKeywordAsync(AddInsideMethod(
            """
            var x = [new object(), $$
            """));
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70677")]
    public async Task TestInCollectionExpressions_AfterFirstElementToReturn()
    {
        await VerifyKeywordAsync(
            """
            class C
            {
                IEnumerable<string> M() => [string.Empty, $$
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70677")]
    public async Task TestInCollectionExpressions_SpreadBeforeFirstElementToReturn()
    {
        await VerifyKeywordAsync(
            """
            class C
            {
                IEnumerable<string> M() => [.. $$
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70677")]
    public async Task TestInCollectionExpressions_SpreadAfterFirstElementToReturn()
    {
        await VerifyKeywordAsync(
            """
            class C
            {
                IEnumerable<string> M() => [string.Empty, .. $$
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70677")]
    public async Task TestInCollectionExpressions_ParenAtFirstElementToReturn()
    {
        await VerifyKeywordAsync(
            """
            class C
            {
                IEnumerable<string> M() => [($$
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70677")]
    public async Task TestInCollectionExpressions_ParenAfterFirstElementToReturn()
    {
        await VerifyKeywordAsync(
            """
            class C
            {
                IEnumerable<string> M() => [string.Empty, ($$
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70677")]
    public async Task TestInCollectionExpressions_ParenSpreadAtFirstElementToReturn()
    {
        await VerifyKeywordAsync(
            """
            class C
            {
                IEnumerable<string> M() => [.. ($$
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70677")]
    public async Task TestInCollectionExpressions_ParenSpreadAfterFirstElementToReturn()
    {
        await VerifyKeywordAsync(
            """
            class C
            {
                IEnumerable<string> M() => [string.Empty, .. ($$
            }
            """);
    }
 
    #endregion
}