' 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.
 
Imports System.Collections.Immutable
Imports System.Threading
Imports Microsoft.CodeAnalysis.Completion.Providers
Imports Microsoft.CodeAnalysis.VisualBasic.Extensions.ContextQuery
 
Namespace Microsoft.CodeAnalysis.VisualBasic.Completion.KeywordRecommenders.PreprocessorDirectives
    ''' <summary>
    ''' Recommends the "#ElseIf" preprocessor directive
    ''' </summary>
    Friend Class ElseIfDirectiveKeywordRecommender
        Inherits AbstractKeywordRecommender
 
        Private Shared ReadOnly s_keywords As ImmutableArray(Of RecommendedKeyword) =
            ImmutableArray.Create(New RecommendedKeyword("#ElseIf", VBFeaturesResources.Introduces_a_condition_in_an_SharpIf_statement_that_is_tested_if_the_previous_conditional_test_evaluates_to_False))
 
        Protected Overrides Function RecommendKeywords(context As VisualBasicSyntaxContext, cancellationToken As CancellationToken) As ImmutableArray(Of RecommendedKeyword)
            If context.IsPreprocessorStartContext OrElse context.IsWithinPreprocessorContext Then
                Dim innermostKind = context.SyntaxTree.GetInnermostIfPreprocessorKind(context.Position, cancellationToken)
 
                If innermostKind.HasValue AndAlso innermostKind.Value <> SyntaxKind.ElseDirectiveTrivia Then
                    Return s_keywords
                End If
            End If
 
            Return ImmutableArray(Of RecommendedKeyword).Empty
        End Function
    End Class
End Namespace