refactor(Scripts/Outland): Update Doomwalker to new register model (#17987)

src/server/scripts/Outland/boss_doomwalker.cpp

@@ -38,14 +38,9 @@ enum Spells
     SPELL_AURA_DEATH        = 37131
 };
 
-class boss_doomwalker : public CreatureScript
+struct boss_doomwalker : public ScriptedAI
 {
-public:
-    boss_doomwalker() : CreatureScript("boss_doomwalker") { }
-
-    struct boss_doomwalkerAI : public ScriptedAI
-    {
-        boss_doomwalkerAI(Creature* creature) : ScriptedAI(creature) {}
+    boss_doomwalker(Creature* creature) : ScriptedAI(creature) { }
 
     void Reset() override
     {
@@ -56,10 +51,8 @@ public:
     void KilledUnit(Unit* victim) override
     {
         victim->CastSpell(victim, SPELL_MARK_DEATH, 0);
-            if (urand(0, 4))
-                return;
 
-            if (victim->GetTypeId() == TYPEID_PLAYER)
+        if (roll_chance_i(25) && victim->IsPlayer())
         {
             Talk(SAY_SLAY);
         }
@@ -87,10 +80,7 @@ public:
             context.Repeat(10s, 25s);
         }).Schedule(10s, 30s, [this](TaskContext context)
         {
-                if (Unit* target = SelectTarget(SelectTargetMethod::Random, 1, 0.0f, true))
-                {
-                    DoCast(target, SPELL_CHAIN_LIGHTNING);
-                }
+            DoCastRandomTarget(SPELL_CHAIN_LIGHTNING, 1);
             context.Repeat(7s, 27s);
         }).Schedule(25s, 35s, [this](TaskContext context)
         {
@@ -130,23 +120,18 @@ public:
             return;
 
         scheduler.Update(diff);
+
         if (me->HasUnitState(UNIT_STATE_CASTING))
             return;
 
         DoMeleeAttackIfReady();
     }
 
-    private:
+private:
     bool _inEnrage;
-    };
-
-    CreatureAI* GetAI(Creature* creature) const override
-    {
-        return new boss_doomwalkerAI (creature);
-    }
 };
 
 void AddSC_boss_doomwalker()
 {
-    new boss_doomwalker();
+    RegisterCreatureAI(boss_doomwalker);
 }