namespace Server.Misc
{
  public static class NameVerification
  {
    public static readonly char[] SpaceDashPeriodQuote =
    {
      ' ', '-', '.', '\''
    };

    public static readonly char[] Empty = new char[0];

    public static string[] StartDisallowed{ get; } =
    {
      "seer",
      "counselor",
      "gm",
      "admin",
      "lady",
      "lord"
    };

    public static string[] Disallowed{ get; } =
    {
      "jigaboo",
      "chigaboo",
      "wop",
      "kyke",
      "kike",
      "tit",
      "spic",
      "prick",
      "piss",
      "lezbo",
      "lesbo",
      "felatio",
      "dyke",
      "dildo",
      "chinc",
      "chink",
      "cunnilingus",
      "cum",
      "cocksucker",
      "cock",
      "clitoris",
      "clit",
      "ass",
      "hitler",
      "penis",
      "nigga",
      "nigger",
      "klit",
      "kunt",
      "jiz",
      "jism",
      "jerkoff",
      "jackoff",
      "goddamn",
      "fag",
      "blowjob",
      "bitch",
      "asshole",
      "dick",
      "pussy",
      "snatch",
      "cunt",
      "twat",
      "shit",
      "fuck",
      "tailor",
      "smith",
      "scholar",
      "rogue",
      "novice",
      "neophyte",
      "merchant",
      "medium",
      "master",
      "mage",
      "lb",
      "journeyman",
      "grandmaster",
      "fisherman",
      "expert",
      "chef",
      "carpenter",
      "british",
      "blackthorne",
      "blackthorn",
      "beggar",
      "archer",
      "apprentice",
      "adept",
      "gamemaster",
      "frozen",
      "squelched",
      "invulnerable",
      "osi",
      "origin"
    };

    public static void Initialize()
    {
      CommandSystem.Register("ValidateName", AccessLevel.Administrator, ValidateName_OnCommand);
    }

    [Usage("ValidateName")]
    [Description("Checks the result of NameValidation on the specified name.")]
    public static void ValidateName_OnCommand(CommandEventArgs e)
    {
      if (Validate(e.ArgString, 2, 16, true, false, true, 1, SpaceDashPeriodQuote))
        e.Mobile.SendMessage(0x59, "That name is considered valid.");
      else
        e.Mobile.SendMessage(0x22, "That name is considered invalid.");
    }

    public static bool Validate(string name, int minLength, int maxLength, bool allowLetters, bool allowDigits,
      bool noExceptionsAtStart, int maxExceptions, char[] exceptions) =>
      Validate(name, minLength, maxLength, allowLetters, allowDigits, noExceptionsAtStart, maxExceptions,
        exceptions, Disallowed, StartDisallowed);

    public static bool Validate(string name, int minLength, int maxLength, bool allowLetters, bool allowDigits,
      bool noExceptionsAtStart, int maxExceptions, char[] exceptions, string[] disallowed, string[] startDisallowed)
    {
      if (name == null || name.Length < minLength || name.Length > maxLength)
        return false;

      int exceptCount = 0;

      name = name.ToLower();

      if (!allowLetters || !allowDigits ||
          exceptions.Length > 0 && (noExceptionsAtStart || maxExceptions < int.MaxValue))
        for (int i = 0; i < name.Length; ++i)
        {
          char c = name[i];

          if (c >= 'a' && c <= 'z')
          {
            if (!allowLetters)
              return false;

            exceptCount = 0;
          }
          else if (c >= '0' && c <= '9')
          {
            if (!allowDigits)
              return false;

            exceptCount = 0;
          }
          else if (exceptCount++ == maxExceptions || exceptions.All(exception => exception != c) ||
                   i == 0 && noExceptionsAtStart)
            return false;
        }

      for (int i = 0; i < disallowed.Length; ++i)
      {
        int indexOf = name.IndexOf(disallowed[i]);

        if (indexOf == -1)
          continue;

        bool badPrefix = indexOf == 0;

        for (int j = 0; !badPrefix && j < exceptions.Length; ++j)
          badPrefix = name[indexOf - 1] == exceptions[j];

        if (!badPrefix)
          continue;

        bool badSuffix = indexOf + disallowed[i].Length >= name.Length;

        for (int j = 0; !badSuffix && j < exceptions.Length; ++j)
          badSuffix = name[indexOf + disallowed[i].Length] == exceptions[j];

        if (badSuffix)
          return false;
      }

      return startDisallowed.All(t => !name.StartsWith(t));
    }
  }
}