// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using System.IO.Pipelines;

#nullable enable

namespace Microsoft.AspNetCore.Connections
{
    internal sealed class CompletionPipeReader : PipeReader
    {
        private readonly PipeReader _inner;

        public bool IsCompleted { get; private set; }
        public Exception? CompleteException { get; private set; }
        public bool IsCompletedSuccessfully => IsCompleted && CompleteException == null;

        public CompletionPipeReader(PipeReader inner)
        {
            _inner = inner;
        }

        public override void AdvanceTo(SequencePosition consumed)
        {
            _inner.AdvanceTo(consumed);
        }

        public override void AdvanceTo(SequencePosition consumed, SequencePosition examined)
        {
            _inner.AdvanceTo(consumed, examined);
        }

        public override ValueTask CompleteAsync(Exception? exception = null)
        {
            IsCompleted = true;
            CompleteException = exception;
            return _inner.CompleteAsync(exception);
        }

        public override void Complete(Exception? exception = null)
        {
            IsCompleted = true;
            CompleteException = exception;
            _inner.Complete(exception);
        }

        public override void CancelPendingRead()
        {
            _inner.CancelPendingRead();
        }

        public override ValueTask<ReadResult> ReadAsync(CancellationToken cancellationToken = default)
        {
            return _inner.ReadAsync(cancellationToken);
        }

        public override bool TryRead(out ReadResult result)
        {
            return _inner.TryRead(out result);
        }

        public void Reset()
        {
            IsCompleted = false;
            CompleteException = null;
        }
    }
}
