feat(Core/AI): Implement ScheduleHealthCheckEvent() for events that fire … (#15275)

src/server/game/AI/ScriptedAI/ScriptedCreature.cpp

@@ -577,6 +577,7 @@ void BossAI::_Reset()
     events.Reset();
     scheduler.CancelAll();
     summons.DespawnAll();
+    _healthCheckEvents.clear();
     if (instance)
         instance->SetBossState(_bossId, NOT_STARTED);
 }
@@ -586,6 +587,7 @@ void BossAI::_JustDied()
     events.Reset();
     scheduler.CancelAll();
     summons.DespawnAll();
+    _healthCheckEvents.clear();
     if (instance)
     {
         instance->SetBossState(_bossId, DONE);
@@ -667,6 +669,39 @@ void BossAI::UpdateAI(uint32 diff)
     DoMeleeAttackIfReady();
 }
 
+void BossAI::DamageTaken(Unit* /*attacker*/, uint32& damage, DamageEffectType /*damagetype*/, SpellSchoolMask /*damageSchoolMask*/)
+{
+    if (!_healthCheckEvents.empty())
+    {
+        _healthCheckEvents.remove_if([&](HealthCheckEventData data) -> bool
+        {
+            return _ProccessHealthCheckEvent(data._healthPct, damage, data._exec);
+        });
+    }
+}
+
+/**
+ * @brief Executes a function once the creature reaches the defined health point percent.
+ *
+ * @param healthPct The health percent at which the code will be executed.
+ * @param exec The fuction to be executed.
+ */
+void BossAI::ScheduleHealthCheckEvent(uint32 healthPct, std::function<void()> exec)
+{
+    _healthCheckEvents.push_back(HealthCheckEventData(healthPct, exec));
+};
+
+bool BossAI::_ProccessHealthCheckEvent(uint8 healthPct, uint32 damage, std::function<void()> exec) const
+{
+    if (me->HealthBelowPctDamaged(healthPct, damage))
+    {
+        exec();
+        return true;
+    }
+
+    return false;
+}
+
 // WorldBossAI - for non-instanced bosses
 
 WorldBossAI::WorldBossAI(Creature* creature) :

src/server/game/AI/ScriptedAI/ScriptedCreature.h

@@ -430,6 +430,14 @@ private:
     bool _isHeroic;
 };
 
+struct HealthCheckEventData
+{
+    HealthCheckEventData(uint8 healthPct, std::function<void()> exec) : _healthPct(healthPct), _exec(exec) { };
+
+    uint8 _healthPct;
+    std::function<void()> _exec;
+};
+
 class BossAI : public ScriptedAI
 {
 public:
@@ -440,12 +448,15 @@ public:
 
     bool CanRespawn() override;
 
+    void DamageTaken(Unit* attacker, uint32& damage, DamageEffectType damagetype, SpellSchoolMask damageSchoolMask) override;
     void JustSummoned(Creature* summon) override;
     void SummonedCreatureDespawn(Creature* summon) override;
     void SummonedCreatureDespawnAll() override;
 
     void UpdateAI(uint32 diff) override;
 
+    void ScheduleHealthCheckEvent(uint32 healthPct, std::function<void()> exec);
+
     // Hook used to execute events scheduled into EventMap without the need
     // to override UpdateAI
     // note: You must re-schedule the event within this method if the event
@@ -464,6 +475,7 @@ protected:
     void _JustEngagedWith();
     void _JustDied();
     void _JustReachedHome() { me->setActive(false); }
+    [[nodiscard]] bool _ProccessHealthCheckEvent(uint8 healthPct, uint32 damage, std::function<void()> exec) const;
 
     void TeleportCheaters();
 
@@ -473,6 +485,7 @@ protected:
 
 private:
     uint32 const _bossId;
+    std::list<HealthCheckEventData> _healthCheckEvents;
 };
 
 class WorldBossAI : public ScriptedAI