[3.3.5] CastSpell unclusterfucking (that's a word now) (#21123)

Core/Spell: The giant CastSpell unclusterfucking (that's a word now) of this generation.

- CastSpell now always takes three arguments - target, spellId, and a struct containing extra arguments
- This struct (CastSpellExtraArgs, see SpellDefines.h) serves as a conglomerate of every previous combination of the 20 billion different CastSpell overloads, all merged into one
  - It has some great utility constructors - check them out! All of these can be used to implicitly construct the ExtraArgs object.
- A gajillion refactors to make everything behave the way it always has

(cherry picked from commit d507a7e3388382960108b24143da48e5f912b4a7)

8 files changed, 23 insertions, 16 deletions

diff --git a/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_anetheron.cpp b/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_anetheron.cpp
index 92866ee6db0..3843e0f8bfd 100644
--- a/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_anetheron.cpp
+++ b/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_anetheron.cpp
@@ -284,8 +284,10 @@ class spell_anetheron_vampiric_aura : public SpellScriptLoader
                 if (!damageInfo || !damageInfo->GetDamage())
                     return;
 
-                int32 bp = damageInfo->GetDamage() * 3;
-                eventInfo.GetActor()->CastCustomSpell(SPELL_VAMPIRIC_AURA_HEAL, SPELLVALUE_BASE_POINT0, bp, eventInfo.GetActor(), true, nullptr, aurEff);
+                Unit* actor = eventInfo.GetActor();
+                CastSpellExtraArgs args(aurEff);
+                args.SpellValueOverrides.AddMod(SPELLVALUE_BASE_POINT0, damageInfo->GetDamage() * 3);
+                actor->CastSpell(actor, SPELL_VAMPIRIC_AURA_HEAL, args);
             }
 
             void Register() override
diff --git a/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_archimonde.cpp b/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_archimonde.cpp
index 92e648bcadf..76ceb2ff034 100644
--- a/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_archimonde.cpp
+++ b/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_archimonde.cpp
@@ -472,8 +472,10 @@ public:
                     DoomfireSpiritGUID = summoned->GetGUID();
                     break;
                 case NPC_DOOMFIRE:
+                {
                     summoned->CastSpell(summoned, SPELL_DOOMFIRE_SPAWN, false);
-                    summoned->CastSpell(summoned, SPELL_DOOMFIRE, true, nullptr, nullptr, me->GetGUID());
+
+                    summoned->CastSpell(summoned, SPELL_DOOMFIRE, me->GetGUID());
 
                     if (Unit* DoomfireSpirit = ObjectAccessor::GetUnit(*me, DoomfireSpiritGUID))
                     {
@@ -481,6 +483,7 @@ public:
                         DoomfireSpiritGUID.Clear();
                     }
                     break;
+                }
                 default:
                     break;
             }
diff --git a/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_kazrogal.cpp b/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_kazrogal.cpp
index ea4adb80dee..1e85927b478 100644
--- a/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_kazrogal.cpp
+++ b/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/boss_kazrogal.cpp
@@ -216,7 +216,7 @@ class spell_mark_of_kazrogal : public SpellScriptLoader
 
                 if (target->GetPower(POWER_MANA) == 0)
                 {
-                    target->CastSpell(target, SPELL_MARK_DAMAGE, true, nullptr, aurEff);
+                    target->CastSpell(target, SPELL_MARK_DAMAGE, aurEff);
                     // Remove aura
                     SetDuration(0);
                 }
diff --git a/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/hyjal_trash.cpp b/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/hyjal_trash.cpp
index cbcb5e81713..4139b6d64ac 100644
--- a/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/hyjal_trash.cpp
+++ b/src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/hyjal_trash.cpp
@@ -1339,7 +1339,7 @@ public:
                 {
                     if (StrikeTimer <= diff)
                     {
-                        me->CastSpell(DummyTarget[0], DummyTarget[1], DummyTarget[2], SPELL_GARGOYLE_STRIKE, false);
+                        me->CastSpell({ DummyTarget[0], DummyTarget[1], DummyTarget[2] }, SPELL_GARGOYLE_STRIKE, false);
                         StrikeTimer = 2000 + rand32() % 1000;
                     } else StrikeTimer -= diff;
                     }
@@ -1452,8 +1452,9 @@ public:
                     EnterEvadeMode();
                     return;
                 }
-                int dmg = 500 + rand32() % 700;
-                me->CastCustomSpell(me->GetVictim(), SPELL_EXPLODING_SHOT, &dmg, nullptr, nullptr, false);
+                CastSpellExtraArgs args;
+                args.SpellValueOverrides.AddMod(SPELLVALUE_BASE_POINT0, 500 + rand32() % 700);
+                me->CastSpell(me->GetVictim(), SPELL_EXPLODING_SHOT, args);
                 ExplodeTimer = 5000 + rand32() % 5000;
             } else ExplodeTimer -= diff;
             DoMeleeAttackIfReady();
diff --git a/src/server/scripts/Kalimdor/HallsOfOrigination/boss_temple_guardian_anhuur.cpp b/src/server/scripts/Kalimdor/HallsOfOrigination/boss_temple_guardian_anhuur.cpp
index fcede66412e..4afebefd140 100644
--- a/src/server/scripts/Kalimdor/HallsOfOrigination/boss_temple_guardian_anhuur.cpp
+++ b/src/server/scripts/Kalimdor/HallsOfOrigination/boss_temple_guardian_anhuur.cpp
@@ -385,9 +385,9 @@ public:
         {
             if (Unit* caster = GetCaster())
             {
-                CustomSpellValues values;
-                values.AddSpellMod(SPELLVALUE_BASE_POINT0, aurEff->GetAmount());
-                caster->CastCustomSpell(aurEff->GetSpellEffectInfo()->TriggerSpell, values, GetTarget());
+                CastSpellExtraArgs args;
+                args.AddSpellMod(SPELLVALUE_BASE_POINT0, aurEff->GetAmount());
+                caster->CastSpell(GetTarget(), aurEff->GetSpellEffectInfo()->TriggerSpell, args);
             }
         }
 
diff --git a/src/server/scripts/Kalimdor/RuinsOfAhnQiraj/boss_buru.cpp b/src/server/scripts/Kalimdor/RuinsOfAhnQiraj/boss_buru.cpp
index 387fa0b1323..882c6c3eb6e 100644
--- a/src/server/scripts/Kalimdor/RuinsOfAhnQiraj/boss_buru.cpp
+++ b/src/server/scripts/Kalimdor/RuinsOfAhnQiraj/boss_buru.cpp
@@ -261,8 +261,9 @@ class spell_egg_explosion : public SpellScriptLoader
             {
                 if (Unit* target = GetHitUnit())
                 {
-                    int32 damage = std::max<int32>(0, -16 * GetCaster()->GetDistance(target) + 500);
-                    GetCaster()->CastCustomSpell(SPELL_EXPLOSION_DAMAGE, SPELLVALUE_BASE_POINT0, damage, target, true);
+                    CastSpellExtraArgs args(TRIGGERED_FULL_MASK);
+                    args.AddSpellBP0(std::max<int32>(0, -16 * GetCaster()->GetDistance(target) + 500));
+                    GetCaster()->CastSpell(target, SPELL_EXPLOSION_DAMAGE, args);
                 }
             }
 
diff --git a/src/server/scripts/Kalimdor/TempleOfAhnQiraj/boss_cthun.cpp b/src/server/scripts/Kalimdor/TempleOfAhnQiraj/boss_cthun.cpp
index 667e36d2d79..0062c33465c 100644
--- a/src/server/scripts/Kalimdor/TempleOfAhnQiraj/boss_cthun.cpp
+++ b/src/server/scripts/Kalimdor/TempleOfAhnQiraj/boss_cthun.cpp
@@ -757,7 +757,7 @@ public:
                             //Set target in stomach
                             Stomach_Map[target->GetGUID()] = true;
                             target->InterruptNonMeleeSpells(false);
-                            target->CastSpell(target, SPELL_MOUTH_TENTACLE, true, nullptr, nullptr, me->GetGUID());
+                            target->CastSpell(target, SPELL_MOUTH_TENTACLE, me->GetGUID());
                             StomachEnterTarget = target->GetGUID();
                             StomachEnterVisTimer = 3800;
                         }
diff --git a/src/server/scripts/Kalimdor/zone_silithus.cpp b/src/server/scripts/Kalimdor/zone_silithus.cpp
index 45c1f0dda2d..dce9b789281 100644
--- a/src/server/scripts/Kalimdor/zone_silithus.cpp
+++ b/src/server/scripts/Kalimdor/zone_silithus.cpp
@@ -503,7 +503,7 @@ public:
                         DoCast(player, SPELL_ARCANE_CHANNELING, true);//Arcane Channeling
                         break;
                     case 35:
-                        me->CastSpell(-8088, 1520.43f, 2.67f, SPELL_TIME_STOP, true);
+                        me->CastSpell({ -8088, 1520.43f, 2.67f }, SPELL_TIME_STOP, true);
                         break;
                     case 36:
                         DoCast(player, SPELL_CALL_PRISMATIC_BARRIER, true);
@@ -553,7 +553,7 @@ public:
                         break;
                     case 50:
                         Fandral->AI()->Talk(FANDRAL_EMOTE_2);
-                        Fandral->CastSpell(-8127, 1525, 17.5f, SPELL_THROW_HAMMER, true);
+                        Fandral->CastSpell({ -8127, 1525, 17.5f }, SPELL_THROW_HAMMER, true);
                         break;
                     case 51:
                     {
@@ -1419,7 +1419,7 @@ class spell_silithus_summon_cultist_periodic : public AuraScript
         // All these spells trigger a spell that requires reagents; if the
         // triggered spell is cast as "triggered", reagents are not consumed
         if (Unit* caster = GetCaster())
-            caster->CastSpell(nullptr, GetSpellInfo()->GetEffect(aurEff->GetEffIndex())->TriggerSpell, TriggerCastFlags(TRIGGERED_FULL_MASK & ~TRIGGERED_IGNORE_POWER_AND_REAGENT_COST), nullptr, aurEff);
+            caster->CastSpell(nullptr, GetSpellInfo()->GetEffect(aurEff->GetEffIndex())->TriggerSpell, CastSpellExtraArgs(TriggerCastFlags(TRIGGERED_FULL_MASK & ~TRIGGERED_IGNORE_POWER_AND_REAGENT_COST)).SetTriggeringAura(aurEff));
     }
 
     void Register() override