using System;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;

namespace DeukBot4.MessageHandlers.CommandHandler.RequestStructure
{
    public static class ParameterMatcher
    {
        public enum ParameterType
        {
            Word,
            Number,
            Remainder,
        }

        public static string[] GenerateRegex(Command command)
        {
            var arr = new string[command.ParameterTypes.Length];
            for (var index = 0; index < command.ParameterTypes.Length; index++)
            {
                var commandParameterType = command.ParameterTypes[index];

                var builder              = new StringBuilder();
                builder.Append(GetParameterRegex(commandParameterType[index]));
                arr[index] = builder.ToString();
            }
            return arr;
        }

        private static string GetParameterRegex(ParameterType type)
        {
            switch (type)
            {
                case ParameterType.Word:
                    return " *(\\w+)";
                case ParameterType.Number:
                    return " *(\\d+)";
                case ParameterType.Remainder:
                    return " *(.*)";
                default:
                    throw new ArgumentOutOfRangeException(nameof(type), type, null);
            }
        }

        public static RequestParameter[] GetParameterValues(Command command, string parameterString)
        {
            foreach (var pattern in command.ParametersMatchers)
            {
                var matches = Regex.Match(parameterString, pattern);
                if (matches.Success)
                {
                    return matches.Groups.Skip(1).Select(x => new RequestParameter(x.Value)).ToArray();
                }
            }
            return new RequestParameter[0];
        }
    }
}