using CanonSharp.Combinator.Abstractions;

namespace CanonSharp.Combinator.Parsers;

/// <summary>
/// 解析器原型基类
/// 实际上就是处理了一个后继调用
/// </summary>
/// <typeparam name="TToken">输入流类型</typeparam>
/// <typeparam name="T">解析结果的类型</typeparam>
public abstract class PrimitiveParser<TToken, T> : Parser<TToken, T>
{
    /// <summary>
    /// 运行解析器 返回解析结果
    /// </summary>
    /// <param name="state">当前输入流的状态</param>
    /// <typeparam name="TState">输入流状态的类型</typeparam>
    /// <returns>解析结果</returns>
    protected abstract ParseResult<TToken, T> Run<TState>(TState state)
        where TState : IReadState<TToken, TState>;

    internal sealed override ParseResult<TToken, TResult> Run<TState, TResult>(TState state,
        Func<ParseResult<TToken, T>, ParseResult<TToken, TResult>> continuation)
        => continuation(Run(state));
}