Classe Lua Color

-------[Classe de Cores por Lynezx | rev 2 - 27/08/2016]-------
Color = {Random = function()
            return Color(math.random(0, 255), math.random(0, 255), math.random(0, 255));
      end,
      Error = function(codigo, parametro)
      local msgs = {"[Color Class] - Invalid hex parameter [%s].",
                  "[Color Class] - Invalid byte parameter [%s]. Value must be a number from 0 to 255.",
                  "[Color Class] - Invalid integer parameter [%s]. Value must be a number from 0 to 16777215.",
                  "[Color Class] - Invalid parameter for Color constructor [%s]. Value must be a hex string; a color integer; a R, G, B bytes sequence or nothing."
             };
            error(string.format((msgs[codigo] or "[Color Class] - Unknown error"), parametro or ""));
      end
};
setmetatable(Color, {
      __call = function(t, ...)
            local args = {...};
            local instancia = {
                  _int = 0,
                  _hex = "000000",
                  _r = 0,
                  _g = 0,
                  _b = 0
            };
            setmetatable(instancia, {
                  __index = function(self, k)
                        return rawget(self, '_' .. k);
                  end,
                  __newindex = function(self, k, v)
                        local alterado = false;
                        local val;
                        if (k == 'int') then
                              --Integer
                              if not(pcall((function()
                                    val = tonumber(v);
                              end))) or (val == nil or val < 0 or val > 0xffffff) then
                                    Color.Error(3, type(v) .. ' ' .. tostring(v));
                              end
                              rawset(self, '_int', val);
                              alterado = true;
                        elseif (k == 'hex') then
                              --Hex
                              if not(pcall((function()
                                    val = tonumber("0x" .. string.gsub(v, '#', '', 1));
                              end))) or val == nil then
                                    Color.Error(1, type(v) .. ' ' .. tostring(v));
                              end
                              rawset(self, '_int', val);
                              alterado = true;
                        elseif (k == 'r' or k == 'g' or k == 'b') then
                              --Byte
                              if not(pcall((function()
                                    val = tonumber(v);
                              end))) or (val == nil or val < 0 or val > 0xff) then
                                    Color.Error(2, type(v) .. ' ' .. tostring(v));
                              end
                              rawset(self, '_' .. k, val);
                              rawset(self, '_int', bit32.lshift(self.r, 16) + bit32.lshift(self.g, 8) + self.b);
                              alterado = true;
                        elseif not alterado then
                              rawset(self, k, val);
                        end
                        --Finalização
                        if alterado then
                              rawset(self, '_r', bit32.band(bit32.rshift(self.int, 16), 0xFF));
                              rawset(self, '_g', bit32.band(bit32.rshift(self.int, 8), 0xFF));
                              rawset(self, '_b', bit32.band(self.int, 0xFF));
                              rawset(self, '_hex', string.format('%02x%02x%02x', self.r, self.g, self.b));
                        end
                  end
            });
            if (#args == 1 and type(args[1]) == 'string') then
                  instancia.hex = args[1];
            elseif (#args == 1 and type(args[1]) == 'number') then
                  instancia.int = args[1];
            elseif (#args == 1 and type(args[1]) == 'table' and type(args[1].int) == 'number') then
                  instancia.int = args[1].int;
            elseif (#args == 1) then
                  Color.Error(4, type(args[1]) .. ' ' .. tostring(args[1]));
            elseif (#args == 3) then
                  instancia.r = args[1];
                  instancia.g = args[2];
                  instancia.b = args[3];
            end
            return instancia;
      end
});
Color.GAME_BACKGROUND = Color('6a7495');
Color.UI_BACKGROUND = Color('0e242d');
Color.UI_BACKGROUND2 = Color('1c3c41');
-------[Classe de Cores por Lynezx | rev 2 - 27/08/2016]-------