add buffs

src/entity.js

@@ -3,17 +3,19 @@ import Pathfind from './pathfind.js'
 import SAT from 'sat'
 import SATX from './satx.js'
 import Team from './team.js'
+import Buff from './buff.js'
 
 export default class Entity {
   id = crypto.randomUUID()
   abilities = {}
+  buffs = []
   casting = null
   cooldowns = {}
   dead = false
   health = null
   height = 40
   maxHealth = 1
-  memory = {}
+  memory = {} // TODO: hide from reports but keep public
   position = null
   radius = 0
   speed = 400
@@ -151,6 +153,17 @@ export default class Entity {
     )
   }
 
+  applyBuff(id) {
+    const index = this.buffs.findIndex((it) => it.id == id)
+    const timestamp = this.game?.currentTick ?? 0
+    if (index > -1) {
+      this.buffs[index].timestamp = timestamp
+    }
+    else {
+      this.buffs.push({ id, timestamp })
+    }
+  }
+
   collidables() {
     const entityColliders = (this.game?.entities ?? []).filter((e) => e.id != this.id).map((e) => e.collider())
     const terrainColliders = (this.game?.terrains ?? []).map((t) => t.colliders()).flat()
@@ -179,7 +192,13 @@ export default class Entity {
   }
 
   damage(amount) {
-    this.health = Math.min(Math.max(0, this.health - amount), this.maxHealth)
+    let damage = amount
+    if (this.hasBuff(Buff.exposed.id)) {
+      damage *= 3 // TODO: move to buff, make generic
+      this.removeBuff(Buff.exposed.id)
+    }
+
+    this.health = Math.min(Math.max(0, this.health - damage), this.maxHealth)
   }
 
   despawn() {
@@ -190,6 +209,10 @@ export default class Entity {
     return this.position.distanceTo(cursor)
   }
 
+  hasBuff(id) {
+    return this.buffs.some((it) => it.id == id)
+  }
+
   heal(amount) {
     this.health = Math.min(Math.max(0, this.health + amount), this.maxHealth)
   }
@@ -202,6 +225,10 @@ export default class Entity {
     return SATX.collideObjects(this.collider(), colliders)
   }
 
+  removeBuff(id) {
+    this.buffs = this.buffs.filter((it) => it.id != id)
+  }
+
   respawn() {
     this.position = this.#spawnPosition.clone()
     this.health = this.maxHealth
@@ -221,6 +248,7 @@ export default class Entity {
       this.#cast()
       this.#checkHealth()
       this.#move()
+      this.#tickBuffs()
       this.fixPosition()
     }
 
@@ -375,4 +403,24 @@ export default class Entity {
       }
     }
   }
+
+  #tickBuff(index) {
+    const entityBuff = this.buffs[index]
+    if (entityBuff == null) { return }
+
+    const buffDefinition = this.game?.buffs.find((it) => it.id == entityBuff.id)
+    if (buffDefinition == null) { return }
+
+    const buff = { ...buffDefinition, ...entityBuff }
+    const duration = this.game?.secToTick(buff.duration) ?? 0
+    const currentTick = this.game?.currentTick ?? 0
+
+    if (buff.timestamp + duration < currentTick) {
+      this.removeBuff(buff.id)
+    }
+  }
+
+  #tickBuffs() {
+    this.buffs.forEach((_v, i) => this.#tickBuff(i))
+  }
 }