xs_obj.script

local type, tostring, sprintf
    = type, tostring, string.format

--[[-----------------------------------------------------------------------\--
    :: Class: XsObj
--\\-----------------------------------------------------------------------]]--

-- TODO Maybe abandon luabind classes altogether?
-- Debugging would be easier, since tables can be compared. And it should
-- be possible to implement a OO-system that mimics luabind.
class "XsObj"

    --[[-------------------------------------------------------------------\--
        :: Fields: Static
    --\\-------------------------------------------------------------------]]--

    local __xs_uid = 0

    --[[-------------------------------------------------------------------\--
        :: Constructor / Finalizer
    --\\-------------------------------------------------------------------]]--

    function XsObj:__init(cls)
        if type(cls) ~= "string" or cls:len() == 0 then
            abort("[XsObj:__init]: Invalid argument #1; expected the name of subclass.")
        end

        __xs_uid = __xs_uid + 1

        self.__uid = __xs_uid
        self.__cls = cls
    end

    --[[-------------------------------------------------------------------\--
        :: Methods: Overloads
    --\\-------------------------------------------------------------------]]--

    -- TODO Move and rename to xs_utils.equals making it a more useful utility.
    function XsObj:__eq(L, R)
        local xL = type(L) == "userdata"
        local xR = type(R) == "userdata"
        if xL and xR then
            -- XsObj
            xL = type(L.__uid) == "number"
            xR = type(R.__uid) == "number"
            if xL and xR then
                return L.__uid == R.__uid
            elseif xL or xR then
                return false
            else
                -- game_object
                xL = type(L.clsid) == "function"
                xR = type(R.clsid) == "function"
                if xL and xR then
                    return L:clsid() == R:clsid() and L:id() == R:id()
                elseif xL or xR then
                    return false
                else
                    abort("[XsObj.__eq]: Unable to determine object equality.")
                end
            end
        elseif xL or xR then
            return false
        else
            return L == R
        end
    end

    function XsObj:__tostring()
        return sprintf("%s [%08X]", self.__cls, self.__uid)
    end

    function XsObj:__add(L, R)
        self:failFromCall("__add")
    end

    function XsObj:__sub(L, R)
        self:failFromCall("__sub")
    end

    function XsObj:__mul(L, R)
        self:failFromCall("__mul")
    end

    function XsObj:__div(L, R)
        self:failFromCall("__div")
    end

    function XsObj:__pow(L, R)
        self:failFromCall("__pow")
    end

    function XsObj:__lt(L, R)
        self:failFromCall("__lt")
    end

    function XsObj:__le(L, R)
        self:failFromCall("__le")
    end

    function XsObj:__call()
        self:failFromCall("__call")
    end

    function XsObj:__unm(obj)
        self:failFromCall("__unm")
    end

    function XsObj:__len(obj)
        self:failFromCall("__len")
    end

    --[[-------------------------------------------------------------------\--
        :: Methods: Private
    --\\-------------------------------------------------------------------]]--

    function XsObj:failFromCall(func)
        abort("[%s:%s]: Unsupported operator/function call.", self.__cls, func)
    end

    --[[-------------------------------------------------------------------\--
        :: Methods: Public
    --\\-------------------------------------------------------------------]]--