Vector3

module("Vector3", package.seeall)

local meta = {
  __index = {
    ObjectType = "Vector3";
    length = function(self)
      return math.sqrt(self.x * self.x + self.y * self.y + self.z * self.z)
    end;

    dot = function(self, vec3)
      return self.x * vec3.x + self.y * vec3.y + self.z * vec3.z
    end;

    cross = function(self, vec3)
      local x_ = self.y * vec3.z - self.z * vec3.y;
      local y_ = self.z * vec3.x - self.x * vec3.z;
      local z_ = self.x * vec3.y - self.y * vec3.x;

      return Vector3.new(x_, y_, z_);
    end;

    normalize = function(self)
      local length = self:length()

      return Vector3.new(self.x / length, self.y / length, self.z / length)
    end;

    inverse = function(self)
      return Vector3.new(self.x * -1, self.y * -1, self.z * -1)
    end;

    max = function(self)
      return math.max(self.x, math.max(self.y, self.z))
    end;

    lerp = function(self, vec3, factor)
      return vec3 - self * factor + self
    end;

    set = function(self, x, y, z)
      self.x = x
      self.y = y
      self.z = z
      return self
    end;

    setVec3 = function(self, vec3)
      self:set(vec3.x, vec3.y, vec3.z)
      return self
    end;
  };
  __newindex = function(self, k, v)
    if (k == "x" or k == "y" or k == "z") then
      self[k] = v
    else
      error("Vector3: The property '"..k.."' is locked.")
    end
  end;

  __add = function(a, b)
    if (type(b) == "number") then
      return Vector3.new(a.x + b, a.y + b, a.z + b)
    else
      return Vector3.new(a.x + b.x, a.y + b.y, a.z + b.z)
    end
  end;

  __sub = function(a, b)
    if (type(b) == "number") then
      return Vector3.new(a.x - b, a.y - b, a.z - b)
    else
      return Vector3.new(a.x - b.x, a.y - b.y, a.z - b.z)
    end
  end;

  __mul = function(a, b)
    if (type(b) == "number") then
      return Vector3.new(a.x * b, a.y * b, a.z * b)
    else
      return Vector3.new(a.x * b.x, a.y * b.y, a.z * b.z)
    end
  end;

  __div = function(a, b)
    if (type(b) == "number") then
      return Vector3.new(a.x / b, a.y / b, a.z / b)
    else
      return Vector3.new(a.x / b.x, a.y / b.y, a.z / b.z)
    end
  end;

  __mod = function(a, b)
    if (type(b) == "number") then
      return Vector3.new(a.x % b, a.y % b, a.z % b)
    else
      return Vector3.new(a.x % b.x, a.y % b.y, a.z % b.z)
    end
  end;

  __pow = function(a, b)
    if (type(b) == "number") then
      return Vector3.new(a.x ^ b, a.y ^ b, a.z ^ b)
    else
      return Vector3.new(a.x ^ b.x, a.y ^ b.y, a.z ^ b.z)
    end
  end;

  __tostring = function(self)
    return "("..self.x..", "..self.y..", "..self.z..")"
  end;

  __eq = function(a, b)
    if (a.x == b.x and a.y == b.y and a.z == b.z) then
      return true
    else
      return false
    end
  end;
}

function new(x, y, z)
  return setmetatable({x = x, y = y, z = z}, meta) --{} has public variables
end