// 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.Collections.Generic;
using Microsoft.CodeAnalysis.Diagnostics;
using Microsoft.CodeAnalysis.Editing;
using Microsoft.CodeAnalysis.Formatting;
using Microsoft.CodeAnalysis.Operations;
using Microsoft.CodeAnalysis.Shared.Extensions;
using Roslyn.Utilities;
 
namespace Microsoft.CodeAnalysis.PopulateSwitch;
 
internal abstract class AbstractPopulateSwitchExpressionCodeFixProvider<
    TExpressionSyntax, TSwitchSyntax, TSwitchArmSyntax, TMemberAccessExpressionSyntax>
    : AbstractPopulateSwitchCodeFixProvider<
        ISwitchExpressionOperation, TSwitchSyntax, TSwitchArmSyntax, TMemberAccessExpressionSyntax>
    where TExpressionSyntax : SyntaxNode
    where TSwitchSyntax : TExpressionSyntax
    where TSwitchArmSyntax : SyntaxNode
    where TMemberAccessExpressionSyntax : TExpressionSyntax
{
    protected AbstractPopulateSwitchExpressionCodeFixProvider()
        : base(IDEDiagnosticIds.PopulateSwitchExpressionDiagnosticId)
    {
    }
 
    protected sealed override void FixOneDiagnostic(
        Document document, SyntaxEditor editor, SemanticModel semanticModel,
        bool addCases, bool addDefaultCase, bool onlyOneDiagnostic,
        bool hasMissingCases, bool hasMissingDefaultCase,
        TSwitchSyntax switchNode, ISwitchExpressionOperation switchExpression)
    {
        var newSwitchNode = UpdateSwitchNode(
            editor, semanticModel, addCases, addDefaultCase,
            hasMissingCases, hasMissingDefaultCase,
            switchNode, switchExpression).WithAdditionalAnnotations(Formatter.Annotation);
 
        editor.ReplaceNode(switchNode, newSwitchNode);
    }
 
    protected sealed override ITypeSymbol GetSwitchType(ISwitchExpressionOperation switchExpression)
        => switchExpression.Value.Type ?? throw ExceptionUtilities.Unreachable();
 
    protected sealed override ICollection<ISymbol> GetMissingEnumMembers(ISwitchExpressionOperation switchOperation)
        => PopulateSwitchExpressionHelpers.GetMissingEnumMembers(switchOperation);
 
    protected override bool HasNullSwitchArm(ISwitchExpressionOperation switchOperation)
        => PopulateSwitchExpressionHelpers.HasNullSwitchArm(switchOperation);
 
    protected static TExpressionSyntax Exception(SyntaxGenerator generator, Compilation compilation)
        => (TExpressionSyntax)generator.CreateThrowNotImplementedExpression(compilation);
 
    protected sealed override int InsertPosition(ISwitchExpressionOperation switchExpression)
    {
        // If the last section has a default label, then we want to be above that.
        // Otherwise, we just get inserted at the end.
 
        var arms = switchExpression.Arms;
        return arms.Length > 0 && PopulateSwitchExpressionHelpers.IsDefault(arms[^1])
            ? arms.Length - 1
            : arms.Length;
    }
}