// 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.
 
#if HAS_IOPERATION
 
namespace Analyzer.Utilities.Lightup
{
    using System;
    using System.Collections.Immutable;
    using System.Diagnostics.CodeAnalysis;
    using Microsoft.CodeAnalysis;
 
    [SuppressMessage("Performance", "CA1815:Override equals and operator equals on value types", Justification = "Not a comparable instance.")]
    internal readonly struct ICollectionExpressionOperationWrapper : IOperationWrapper
    {
        internal const string WrappedTypeName = "Microsoft.CodeAnalysis.Operations.ICollectionExpressionOperation";
        private static readonly Type? WrappedType = OperationWrapperHelper.GetWrappedType(typeof(ICollectionExpressionOperationWrapper));
 
        private static readonly Func<IOperation, ImmutableArray<IOperation>> ElementsAccessor = LightupHelpers.CreateOperationPropertyAccessor<IOperation, ImmutableArray<IOperation>>(WrappedType, nameof(Elements), fallbackResult: default);
 
        private ICollectionExpressionOperationWrapper(IOperation operation)
        {
            WrappedOperation = operation;
        }
 
        public IOperation WrappedOperation { get; }
        public ITypeSymbol? Type => WrappedOperation.Type;
        public ImmutableArray<IOperation> Elements => ElementsAccessor(WrappedOperation);
 
        public static ICollectionExpressionOperationWrapper FromOperation(IOperation operation)
        {
            if (operation == null)
            {
                return default;
            }
 
            if (!IsInstance(operation))
            {
                throw new InvalidCastException($"Cannot cast '{operation.GetType().FullName}' to '{WrappedTypeName}'");
            }
 
            return new ICollectionExpressionOperationWrapper(operation);
        }
 
        public static bool IsInstance(IOperation operation)
        {
            return operation != null && LightupHelpers.CanWrapOperation(operation, WrappedType);
        }
    }
}
 
#endif