Core/Spells & Vehicles: Define and implement SPELL_ATTR6_CASTABLE_WHILE_ON_VEHICLE and VEHICLE_SEAT_FLAG_CAN_CAST_MOUNT_SPELL.

Research done by QAston

src/server/game/Entities/Vehicle/Vehicle.h

@@ -52,8 +52,9 @@ enum VehicleSeatFlags
     VEHICLE_SEAT_FLAG_HIDE_PASSENGER             = 0x00000200,           // Passenger is hidden
     VEHICLE_SEAT_FLAG_UNK11                      = 0x00000400,           // needed for CGCamera__SyncFreeLookFacing
     VEHICLE_SEAT_FLAG_CAN_CONTROL                = 0x00000800,           // Lua_UnitInVehicleControlSeat
+    VEHICLE_SEAT_FLAG_CAN_CAST_MOUNT_SPELL       = 0x00001000,           // Can cast spells with SPELL_AURA_MOUNTED from seat (possibly 4.x only, 0 seats on 3.3.5a)
     VEHICLE_SEAT_FLAG_UNCONTROLLED               = 0x00002000,           // can override !& VEHICLE_SEAT_FLAG_CAN_ENTER_OR_EXIT
-    VEHICLE_SEAT_FLAG_CAN_ATTACK                 = 0x00004000,           // Can attack, cast spells and use items from vehicle?
+    VEHICLE_SEAT_FLAG_CAN_ATTACK                 = 0x00004000,           // Can attack, cast spells and use items from vehicle
     VEHICLE_SEAT_FLAG_CAN_ENTER_OR_EXIT          = 0x02000000,           // Lua_CanExitVehicle - can enter and exit at free will
     VEHICLE_SEAT_FLAG_CAN_SWITCH                 = 0x04000000,           // Lua_CanSwitchVehicleSeats
     VEHICLE_SEAT_FLAG_CAN_CAST                   = 0x20000000,           // Lua_UnitHasVehicleUI
@@ -103,6 +104,7 @@ class Vehicle
 {
     friend class Unit;
     friend class WorldSession;
+    friend class Spell;
 
     public:
         explicit Vehicle(Unit* unit, VehicleEntry const* vehInfo, uint32 creatureEntry);

src/server/game/Miscellaneous/SharedDefines.h

@@ -491,7 +491,7 @@ enum SpellAttr6
     SPELL_ATTR6_UNK9                             = 0x00000200, //  9
     SPELL_ATTR6_CAN_TARGET_POSSESSED_FRIENDS     = 0x00000400, // 10 NYI!
     SPELL_ATTR6_NOT_IN_RAID_INSTANCE             = 0x00000800, // 11 not usable in raid instance
-    SPELL_ATTR6_UNK12                            = 0x00001000, // 12
+    SPELL_ATTR6_CASTABLE_WHILE_ON_VEHICLE        = 0x00001000, // 12 castable while caster is on vehicle
     SPELL_ATTR6_UNK13                            = 0x00002000, // 13
     SPELL_ATTR6_UNK14                            = 0x00004000, // 14
     SPELL_ATTR6_UNK15                            = 0x00008000, // 15 not set in 3.0.3

src/server/game/Spells/Spell.cpp

@@ -449,7 +449,7 @@ SpellValue::SpellValue(SpellInfo const* proto)
     AuraStackAmount = 1;
 }
 
-Spell::Spell(Unit* Caster, SpellInfo const *info, bool triggered, uint64 originalCasterGUID, bool skipCheck, bool castedClientside):
+Spell::Spell(Unit* Caster, SpellInfo const *info, bool triggered, uint64 originalCasterGUID, bool skipCheck):
 m_spellInfo(sSpellMgr->GetSpellForDifficultyFromSpell(info, Caster)),
 m_caster(Caster), m_spellValue(new SpellValue(m_spellInfo))
 {
@@ -4180,7 +4180,7 @@ void Spell::SendChannelStart(uint32 duration)
 {
     WorldObject* target = NULL;
 
-    // select first not resisted target from target list for _0_ effect
+    // select first not resisted target from target list for first available effect
     if (!m_UniqueTargetInfo.empty())
     {
         for (std::list<TargetInfo>::const_iterator itr = m_UniqueTargetInfo.begin(); itr != m_UniqueTargetInfo.end(); ++itr)
@@ -4722,6 +4722,33 @@ SpellCastResult Spell::CheckCast(bool strict)
             return SPELL_FAILED_MOVING;
     }
 
+    if (Vehicle* vehicle = m_caster->GetVehicle())
+    {
+        uint16 checkMask = 0;
+        for (uint8 effIndex = EFFECT_0; effIndex < MAX_SPELL_EFFECTS; ++effIndex)
+        {
+            SpellEffectInfo const* effInfo = &m_spellInfo->Effects[effIndex];
+            if (effInfo->ApplyAuraName == SPELL_AURA_MOD_SHAPESHIFT)
+            {
+                SpellShapeshiftEntry const* shapeShiftEntry = sSpellShapeshiftStore.LookupEntry(effInfo->MiscValue);
+                if (shapeShiftEntry && (shapeShiftEntry->flags1 & 1) == 0)  // unk flag
+                    checkMask |= VEHICLE_SEAT_FLAG_UNCONTROLLED;
+                break;
+            }
+        }
+
+        if (m_spellInfo->HasAura(SPELL_AURA_MOUNTED))
+            checkMask |= VEHICLE_SEAT_FLAG_CAN_CAST_MOUNT_SPELL;
+
+        if (!checkMask)
+            checkMask = VEHICLE_SEAT_FLAG_CAN_ATTACK;
+
+        VehicleSeatEntry const* vehicleSeat = vehicle->GetSeatForPassenger(m_caster);
+        if (!(m_spellInfo->AttributesEx6 & SPELL_ATTR6_CASTABLE_WHILE_ON_VEHICLE) && !(m_spellInfo->Attributes & SPELL_ATTR0_CASTABLE_WHILE_MOUNTED)
+            && (vehicleSeat->m_flags & checkMask) != checkMask)
+            return SPELL_FAILED_DONT_REPORT;
+    }
+
     Unit* target = m_targets.GetUnitTarget();
     // In pure self-cast spells, the client won't send any unit target
     if (!target && (m_targets.GetTargetMask() == TARGET_FLAG_SELF || m_targets.GetTargetMask() & TARGET_FLAG_UNIT_ALLY)) // TARGET_FLAG_SELF == 0, remember!

src/server/game/Spells/Spell.h

@@ -379,7 +379,7 @@ class Spell
 
         typedef std::set<Aura*> UsedSpellMods;
 
-        Spell(Unit* Caster, SpellInfo const *info, bool triggered, uint64 originalCasterGUID = 0, bool skipCheck = false, bool castedClientside = false);
+        Spell(Unit* Caster, SpellInfo const *info, bool triggered, uint64 originalCasterGUID = 0, bool skipCheck = false);
         ~Spell();
 
         void prepare(SpellCastTargets const* targets, AuraEffect const* triggeredByAura = NULL);