using CanonSharp.Combinator;
using CanonSharp.Combinator.Abstractions;
using CanonSharp.Common.Scanner;

namespace CanonSharp.Tests.Utils;

public abstract class ParserTestsBase
{
    protected static void ValidateSuccessfulResult<T>(Parser<char, T> parser, T value, string source)
    {
        StringReadState state = new(source);

        ParseResult<char, T> result = parser.Parse(state);
        Assert.Equal(value, result.Value);
    }

    protected static void ValidateSuccessfulResult<T>(
        Parser<char, IEnumerable<T>> parser,
        IEnumerable<T> values, string source)
    {
        StringReadState state = new(source);

        ParseResult<char, IEnumerable<T>> result = parser.Parse(state);

        foreach ((T actual, T except) in result.Value.Zip(values))
        {
            Assert.Equal(except, actual);
        }
    }

    protected static FailedResult<char, T> ValidateFailedResult<T>(Parser<char, T> parser, string source)
    {
        StringReadState state = new(source);

        ParseResult<char, T> result = parser.Parse(state);
        Assert.ThrowsAny<ParseException>(() =>
        {
            _ = result.Value;
        });

        return (FailedResult<char, T>)result;
    }
}