Rainbow Tag

/// Struct defining a rainbow tag, [rb].
struct rainbowtag: bbcode_tag {
  void init() { }
  string get_replacement(PurpleConversation*, PurpleAccount*, int, string content, string, string) {
    char colors[10] = { '4', '7', '8', '3', '2', '6' };
    string res = "\00304"; int color = 0;
    for (const char* uc = content.c_str(); *uc; ) {
      const char *ucf = uc; uc = g_utf8_next_char(uc);
      res += string(ucf,uc);
      gunichar c = g_utf8_get_char(ucf);
      if (!g_unichar_isspace(c)) {
        res += "\0030", res += colors[++color % 6];
      }
    }
    return res;
  }
  rainbowtag(): bbcode_tag("rb",false) {}
};