// 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 FromKeywordRecommenderTests : 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 TestNotInEmptyStatement()
    {
        await VerifyAbsenceAsync(AddInsideMethod(
@"$$"));
    }
 
    [Fact]
    public async Task TestInEmptySpace()
    {
        await VerifyKeywordAsync(AddInsideMethod(
@"var v = $$"));
    }
 
    [Fact]
    public async Task TestAfterIdentifier()
    {
        await VerifyKeywordAsync(AddInsideMethod(
@"var v = a$$"));
    }
 
    [Fact]
    public async Task TestNestedInQueryExpression()
    {
        await VerifyKeywordAsync(AddInsideMethod(
@"var q = from x in $$"));
    }
 
    [Fact]
    public async Task TestAfterFrom()
    {
        await VerifyKeywordAsync(AddInsideMethod(
            """
            var v = from x in y
                      $$
            """));
    }
 
    [Fact]
    public async Task TestAfterPreviousClause()
    {
        await VerifyKeywordAsync(AddInsideMethod(
            """
            var v = from x in y
                      where x > y
                      $$
            """));
    }
 
    [Fact]
    public async Task TestAfterPreviousContinuationClause()
    {
        await VerifyKeywordAsync(AddInsideMethod(
            """
            var v = from x in y
                      group x by y into g
                      $$
            """));
    }
 
    [Fact]
    public async Task TestNotAfterFrom1()
    {
        await VerifyAbsenceAsync(AddInsideMethod(
@"var v = from $$"));
    }
 
    [Fact]
    public async Task TestNotAfterFrom2()
    {
        await VerifyAbsenceAsync(AddInsideMethod(
            """
            var v = from a in y
                      from $$
            """));
    }
 
    [Fact]
    public async Task TestBetweenClauses()
    {
        await VerifyKeywordAsync(AddInsideMethod(
            """
            var v = from x in y
                      $$
                      from z in w
            """));
    }
 
    [Fact]
    public async Task TestContinueInSelect()
    {
        await VerifyKeywordAsync(AddInsideMethod(
            """
            var v = from x in y
                      select $$
            """));
    }
 
    [Fact]
    public async Task TestBetweenTokens()
    {
        await VerifyKeywordAsync(AddInsideMethod(
@"var v =$$;"));
    }
 
    [Fact]
    public async Task TestNotInDeclaration()
    {
        await VerifyAbsenceAsync(AddInsideMethod(
@"int $$"));
    }
 
    [Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/538264")]
    public async Task TestNotInEnumMemberInitializer1()
    {
        await VerifyAbsenceAsync(
            """
            enum E {
                a = $$
            }
            """);
    }
 
    [Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/538264")]
    public async Task TestNotInConstMemberInitializer1()
    {
        await VerifyAbsenceAsync(
            """
            class E {
                const int a = $$
            }
            """);
    }
 
    [Fact, WorkItem("http://vstfdevdiv:8080/DevDiv2/DevDiv/_workitems/edit/538264")]
    public async Task TestInMemberInitializer1()
    {
        await VerifyKeywordAsync(
            """
            class E {
                int a = $$
            }
            """);
    }
 
    [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/544219")]
    public async Task TestNotInObjectInitializerMemberContext()
    {
        await VerifyAbsenceAsync("""
            class C
            {
                public int x, y;
                void M()
                {
                    var c = new C { x = 2, y = 3, $$
            """);
    }
 
    [Fact]
    public async Task TestNotAfterOutInArgument()
    {
        var experimentalFeatures = new System.Collections.Generic.Dictionary<string, string>(); // no experimental features to enable
        await VerifyAbsenceAsync("""
            class C
            {
                void M(out int x) { x = 42; }
 
                void N()
                {
                    M(out var $$
            """, options: Options.Regular.WithFeatures(experimentalFeatures), scriptOptions: Options.Script.WithFeatures(experimentalFeatures));
    }
 
    #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
}