[7980] Implement item use target requirements store and check (new table item_required_target). Author: NoFantasy

Signed-off-by: VladimirMangos <vladimir@getmangos.com>

    * Also implement this table reload
    * Static Spell::SendCastResult function for call not from spell code.
      Can be also used in scripts where need send explicitly spell cast error to client.

--HG--
branch : trunk

src/game/Item.cpp

@@ -776,6 +776,23 @@ bool Item::IsFitToSpellRequirements(SpellEntry const* spellInfo) const
     return true;
 }
 
+bool Item::IsTargetValidForItemUse(Unit* pUnitTarget)
+{
+    ItemRequiredTargetMapBounds bounds = objmgr.GetItemRequiredTargetMapBounds(GetProto()->ItemId);
+
+    if (bounds.first == bounds.second)
+        return true;
+
+    if (!pUnitTarget)
+        return false;
+
+    for(ItemRequiredTargetMap::const_iterator itr = bounds.first; itr != bounds.second; ++itr)
+        if(itr->second.IsFitToRequirements(pUnitTarget))
+            return true;
+
+    return false;
+}
+
 void Item::SetEnchantment(EnchantmentSlot slot, uint32 id, uint32 duration, uint32 charges)
 {
     // Better lost small time at check in comparison lost time at item save to DB.
@@ -982,3 +999,16 @@ bool Item::IsBindedNotWith( Player const* player ) const
         return objmgr.GetPlayerAccountIdByGUID(GetOwnerGUID()) != player->GetSession()->GetAccountId();
     }
 }
+
+bool ItemRequiredTarget::IsFitToRequirements( Unit* pUnitTarget ) const
+{
+    switch(m_uiType)
+    {
+        case ITEM_TARGET_TYPE_CREATURE:
+            return pUnitTarget->isAlive();
+        case ITEM_TARGET_TYPE_DEAD:
+            return !pUnitTarget->isAlive();
+        default:
+            return false;
+    }
+}