using CanonSharp.Combinator.Abstractions;

namespace CanonSharp.Combinator.Parsers.Bases;

/// <summary>
/// 单子解析器
/// </summary>
/// <param name="parser">上游解析器</param>
/// <param name="next">下游解析器生成函数</param>
/// <typeparam name="TToken">输入流类型</typeparam>
/// <typeparam name="TIntermediate">上游解析器结果类型</typeparam>
/// <typeparam name="T">下游解析器结果类型</typeparam>
internal sealed class BindParser<TToken, TIntermediate, T>(
    IParser<TToken, TIntermediate> parser,
    Func<TIntermediate, IParser<TToken, T>> next) : IParser<TToken, T>
{
    public IParseResult<TToken, TResult> Run<TState, TResult>(TState state,
        Func<IParseResult<TToken, T>, IParseResult<TToken, TResult>> continuation)
        where TState : IReadState<TToken, TState>
        => parser.Run(state, result => result.Next(next, continuation));
}