explain item qualities better

diff --git a/ArtifactMenu.lua b/ArtifactMenu.lua
index 4be4b4c..b418bb5 100644
--- a/ArtifactMenu.lua
+++ b/ArtifactMenu.lua
@@ -11,14 +11,23 @@ local function openOffhandSockets()
 end

 function SlashCmdList.ARTIFACTMENU(msg, editBox)
-    local ARTIFACT = 6; -- http://wowprogramming.com/docs/api_types#itemQuality
+    -- http://wowprogramming.com/docs/api_types#itemQuality
+    local QUALITY = {}
+    QUALITY.POOR = 0;
+    QUALITY.COMMON = 1;
+    QUALITY.UNCOMMON = 2;
+    QUALITY.RARE = 3;
+    QUALITY.EPIC = 4;
+    QUALITY.LEGENDARY = 5;
+    QUALITY.ARTIFACT = 6;
+    QUALITY.HEIRLOOM = 7;
     local equippedWeapon = GetInventoryItemID("player", GetInventorySlotInfo("MainHandSlot"));
     if equippedWeapon == nil then
         print("You do not have any weapons equipped.");
         return
     end
     name, link, quality, iLvl, reqLvl, class, subclass, maxStack, equipSlot, texture, vendorSellPrice = GetItemInfo(equippedWeapon);
-    if quality == ARTIFACT then
+    if quality == QUALITY["ARTIFACT"] then
         openWeaponSockets();
     else
         print("You do not have an Artifact Weapon equipped yet.");