// 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.
 
namespace Roslyn.LanguageServer.Protocol
{
    using System;
    using System.Text.Json.Serialization;
 
    /// <summary>
    /// Represents a parameter of a callable-signature. A parameter can 
    /// have a label and documentation.
    /// <para>
    /// See the <see href="https://microsoft.github.io/language-server-protocol/specifications/specification-current/#parameterInformation">Language Server Protocol specification</see> for additional information.
    /// </para>
    /// </summary>
    [JsonConverter(typeof(ParameterInformationConverter))]
    internal class ParameterInformation
    {
        /// <summary>
        /// The label of this parameter information.
        /// <para>
        /// Either a string or an inclusive start and exclusive end offsets within
        /// its containing signature label (see <see cref="SignatureInformation.Label"/>).
        /// The offsets are based on a UTF-16 string representation, like <see cref="Position"/> and
        /// <see cref="Range"/>.
        /// </para>
        /// <para>
        /// Note*: a label of type <see langword="string"/> should be a substring of its containing
        /// signature label. Its intended use case is to highlight the parameter
        /// label part in the <see cref="SignatureInformation.Label"/>.
        /// </para>
        /// </summary>
        [JsonPropertyName("label")]
        public SumType<string, Tuple<int, int>> Label
        {
            get;
            set;
        }
 
        /// <summary>
        /// Human-readable documentation of the parameter. Will be shown in the UI but can be omitted.
        /// </summary>
        [JsonPropertyName("documentation")]
        [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
        public SumType<string, MarkupContent>? Documentation
        {
            get;
            set;
        }
    }
}