using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace GpsClient2 {
    public static class StringExtensions {
        private const string Pattern = @"(\d{2})(\d{2})(\d{2})[.\d{2}]?";

        public static TimeSpan ToTimeSpan(this string inputString) {
            var regexMatch = Regex.Match(inputString, Pattern);
            return regexMatch.Groups.Count == 0 ? TimeSpan.Zero : new TimeSpan(0, int.Parse(regexMatch.Groups[1].Value), int.Parse(regexMatch.Groups[2].Value), int.Parse(regexMatch.Groups[3].Value));
        }

        public static double ToCoordinates(this string inputString, string cardinalDirection, CoordinateType coordinateType) {
            if (string.IsNullOrEmpty(inputString)) return 0.0d;

            var degreeCharacters = coordinateType == CoordinateType.Latitude ? 2 : 3;

            var degree = inputString.Substring(0, degreeCharacters).ToDouble();
            degree += inputString.Substring(degreeCharacters).ToDouble() / 60;

            if (!double.IsNaN(degree) && (cardinalDirection == "S" || cardinalDirection == "W")) {
                degree *= -1;
            }
            return degree;
        }

        public static int ToInteger(this string inputString) {
            return !string.IsNullOrEmpty(inputString) ? int.Parse(inputString, CultureInfo.InvariantCulture) : 0;
        }

        public static double ToDouble(this string inputString) {
            return !string.IsNullOrEmpty(inputString) ? double.Parse(inputString, CultureInfo.InvariantCulture) : double.NaN;
        }

        public static float ToFloat(this string inputString) {
            return !string.IsNullOrEmpty(inputString) ? float.Parse(inputString, CultureInfo.InvariantCulture) : float.NaN;
        }

        public static bool ToBoolean(this string inputString, string validValue) {
            return inputString == validValue;
        }

        public static string RemoveAfter(this string inputString, string charValue) {
            var index = inputString.IndexOf(charValue, StringComparison.Ordinal);
            return index > 0 ? inputString.Substring(0, index) : inputString;
        }
    }
}