namespace HeuristicLab.BenchmarkSuite {
  using System;
  using System.Collections.Generic;
  using System.Globalization;
  using System.IO;
  using System.Linq;

  public static class ExampleArgumentConverter {
    private static readonly char[] ArrayValueSeparator = { ' ', ';' };
    private static readonly char[] ArraySymbolTrim = { '[', ']', '(', ')' };

    public static double[] ConvertDoubles(string[] input) {
      return input.Select(ConvertDouble).ToArray();
    }

    public static double[] ConvertDoubles(string input) {
      return ConvertMultiple(input, str => double.Parse(str, NumberStyles.Float, CultureInfo.InvariantCulture));
    }

    public static double ConvertDouble(string input) {
      return double.Parse(input, CultureInfo.InvariantCulture);
    }

    public static long[] ConvertIntegers(string[] input) {
      return input.Select(ConvertInteger).ToArray();
    }

    public static long[] ConvertIntegers(string input) {
      return ConvertMultiple(input, long.Parse);
    }

    public static long ConvertInteger(string input) {

      return string.IsNullOrEmpty(input) ? default(long) : long.Parse(input);
    }

    public static string[] ConvertStringVector(string input) {
      var length = input.Length - 1;
      var strs = new List<string>();

      for (var i = 1; i < length; i++) {
        // collect string
        var c = input[i];

        if (c == ' ') continue;
        if (c != '\"') throw new InvalidDataException("Unable to parse string vector");

        var start = i + 1;
        do {
          i++;
          c = input[i];
        } while (i < length - 1  &&
               !(c == '\"' && input[i + 1] == ' ') &&
               !(i == length - 2 && c == '\"' && input[i + 1] == ']'));


        var str = input.Substring(start, i - start);
        strs.Add(str);
      }

      return strs.ToArray();
    }

    public static T[] ConvertMultiple<T>(string input, Func<string, T> converter) {
      return input
       .Trim(ArraySymbolTrim)
       .Split(ArrayValueSeparator)
       .Where(s => !string.IsNullOrWhiteSpace(s))
       .Select(converter)
       .ToArray();
    }

    public static IEnumerable<string> SplitByNewLine(string input) {
      return input.Split(new[] { Environment.NewLine, "\n", "\r\n" }, StringSplitOptions.None);
    }

    private static string[] trueFormats = { "true", "t", "1" };
    private static string[] falseFormats = { "false", "f", "0" };

    public static bool ConvertBoolean(string input) {
      var str = input.ToLower();

      if (trueFormats.Contains(str)) return true;
      if (falseFormats.Contains(str)) return false;
      throw new InvalidDataException(string.Format("Unable to parse {0} as boolean", str));
    }

    public static bool[] ConvertBooleans(string input) {
      return input
        .Trim(ArraySymbolTrim)
        .Split(ArrayValueSeparator)
        .Where(s => !string.IsNullOrWhiteSpace(s))
        .Select(ConvertBoolean)
        .ToArray();
    }
  }
}