' 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.Threading
Imports Microsoft.CodeAnalysis.Options
Imports Microsoft.CodeAnalysis.PooledObjects
Imports Microsoft.CodeAnalysis.Simplification
Imports Microsoft.CodeAnalysis.VisualBasic.Syntax
 
Namespace Microsoft.CodeAnalysis.VisualBasic.Simplification
    Partial Friend Class VisualBasicMiscellaneousReducer
        Inherits AbstractVisualBasicReducer
 
        Private Shared ReadOnly s_pool As ObjectPool(Of IReductionRewriter) =
            New ObjectPool(Of IReductionRewriter)(Function() New Rewriter(s_pool))
 
        Private Shared ReadOnly s_simplifyParameter As Func(Of ParameterSyntax, SemanticModel, SimplifierOptions, CancellationToken, ParameterSyntax) = AddressOf SimplifyParameter
 
        Public Sub New()
            MyBase.New(s_pool)
        End Sub
 
        Public Overrides Function IsApplicable(options As VisualBasicSimplifierOptions) As Boolean
            Return True
        End Function
 
        Private Shared Function SimplifyParameter(
            parameter As ParameterSyntax,
            semanticModel As SemanticModel,
            options As SimplifierOptions,
            cancellationToken As CancellationToken
        ) As ParameterSyntax
            If parameter.CanRemoveAsClause(semanticModel, cancellationToken) Then
                Dim newParameter = parameter.WithAsClause(Nothing).NormalizeWhitespace()
                newParameter = SimplificationHelpers.CopyAnnotations(parameter, newParameter).WithoutAnnotations(Simplifier.Annotation)
                Return newParameter
            End If
 
            Return parameter
        End Function
 
        Private Shared ReadOnly s_simplifyInvocationExpression As Func(Of InvocationExpressionSyntax, SemanticModel, SimplifierOptions, CancellationToken, SyntaxNode) = AddressOf SimplifyInvocationExpression
 
        Private Shared Function SimplifyInvocationExpression(
            invocationExpression As InvocationExpressionSyntax,
            semanticModel As SemanticModel,
            options As SimplifierOptions,
            cancellationToken As CancellationToken
        ) As InvocationExpressionSyntax
 
            If invocationExpression.CanRemoveEmptyArgumentList(semanticModel) Then
                Dim resultNode = invocationExpression _
                    .WithArgumentList(Nothing) _
                    .WithTrailingTrivia(invocationExpression.GetTrailingTrivia())
 
                resultNode = SimplificationHelpers.CopyAnnotations(invocationExpression, resultNode)
 
                Return resultNode
            End If
 
            ' We don't know how to simplify this.
            Return invocationExpression
        End Function
 
        Private Shared ReadOnly s_simplifyObjectCreationExpression As Func(Of ObjectCreationExpressionSyntax, SemanticModel, SimplifierOptions, CancellationToken, SyntaxNode) = AddressOf SimplifyObjectCreationExpression
 
        Private Shared Function SimplifyObjectCreationExpression(
            objectCreationExpression As ObjectCreationExpressionSyntax,
            semanticModel As SemanticModel,
            options As SimplifierOptions,
            cancellationToken As CancellationToken
        ) As ObjectCreationExpressionSyntax
 
            If objectCreationExpression.CanRemoveEmptyArgumentList() Then
                Dim resultNode = objectCreationExpression _
                    .WithArgumentList(Nothing) _
                    .WithTrailingTrivia(objectCreationExpression.GetTrailingTrivia())
 
                resultNode = SimplificationHelpers.CopyAnnotations(objectCreationExpression, resultNode)
 
                Return resultNode
            End If
 
            ' We don't know how to simplify this.
            Return objectCreationExpression
        End Function
    End Class
End Namespace