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

namespace System.Net.ServerSentEvents
{
    /// <summary>Provides options for parsing server-sent events.</summary>
    /// <typeparam name="T">Specifies the type of data parsed from an event.</typeparam>
    public sealed class SseParserOptions<T>
    {
        /// <summary>Initializes a new instance of the <see cref="SseParserOptions{T}"/> class.</summary>
        /// <param name="itemParser">The parser to use to transform each payload of bytes into a data element.</param>
        /// <exception cref="ArgumentNullException"><paramref name="itemParser"/> is null.</exception>
        public SseParserOptions(SseItemParser<T> itemParser)
        {
            ThrowHelper.ThrowIfNull(itemParser, nameof(itemParser));

            ItemParser = itemParser;
        }

        /// <summary>Gets the parser to use to transform each payload of bytes into a data element.</summary>
        public SseItemParser<T> ItemParser { get; }

        /// <summary>Gets or sets the maximum buffer size requested from the underlying allocator, or -1 to use the default limit.</summary>
        /// <exception cref="ArgumentOutOfRangeException">The value set is less than -1.</exception>
        /// <remarks>The limit is enforced on a best-effort basis. The permitted memory consumption may be several times higher than the configured limit. Values smaller than the internal minimum buffer size are treated as that minimum.</remarks>
        public int MaxBufferSize
        {
            get => _maxBufferSize;
            set
            {
                if (value < -1)
                {
                    ThrowHelper.ThrowArgumentOutOfRangeException(nameof(value));
                }

                _maxBufferSize = value;
            }
        }

        private int _maxBufferSize = -1;
    }
}