feat: implement freeze effect

include/game/Mobs.h

@@ -34,6 +34,7 @@ typedef std::uint32_t MobID;
 typedef std::uint8_t MobLevel;
 typedef std::vector<TowerType> TowerImmunities;
 typedef std::vector<EffectType> EffectImmunities;
+typedef std::pair<EffectType, float> EffectDuration;
 
 class MobStats {
 private:
@@ -71,6 +72,7 @@ private:
     PlayerID m_Sender;
     MobLevel m_Level;
     Direction m_Direction;
+    std::vector<EffectDuration> m_Effects;
 
     float m_X = 0, m_Y = 0;
 public:
@@ -80,7 +82,7 @@ public:
 
     virtual MobType getType() const = 0;
 
-    virtual void tick(std::uint64_t delta) {}
+    virtual void tick(std::uint64_t delta);
 
     const TowerImmunities& getTowerImmunities() const { return getMobTowerImmunities(getType(), m_Level); }
     const EffectImmunities& getEffectImmunities() const { return getMobEffectImmunities(getType(), m_Level); }
@@ -99,10 +101,19 @@ public:
     float getY() const { return m_Y; }
     void setY(float y) { m_Y = y; }
 
+    bool isImmuneTo(TowerType type);
+
+    bool isImmuneTo(EffectType type);
+    void addEffect(EffectType type, float durationSec);
+    bool hasEffect(EffectType type);
+
+
     Direction getDirection() const { return m_Direction; }
     void setDirection(Direction dir) { m_Direction = dir; }
 protected:
     void initHealth() { m_Health = (float)getStats()->getMaxLife(); }
+private:
+    void updateEffects(std::uint64_t delta);
 };
 
 typedef std::shared_ptr<Mob> MobPtr;