using CanonSharp.Combinator.Abstractions;

namespace CanonSharp.Combinator.Results;

/// <summary>
/// 消息类型的失败解析结果
/// </summary>
/// <param name="message">解析失败的消息</param>
/// <param name="state">当前读取的状态</param>
/// <typeparam name="TToken">输入流的类型</typeparam>
/// <typeparam name="TState">读取状态类型</typeparam>
/// <typeparam name="T">解析结果的类型</typeparam>
internal sealed class FailedResultWithMessage<TToken, TState, T>(string message, TState state)
    : IFailedResult<TToken, T>
    where TState : IReadState<TToken, TState>
{
    public IReadState<TToken> State => state;

    public string Message => message;

    public IFailedResult<TToken, TNext> Convert<TNext>()
    {
        return new FailedResultWithMessage<TToken, TState, TNext>(message, state);
    }

    public override string ToString() => $"Parse failed: {Message}.";
}