refactor: create ItemManger class

- add itemManager class and moved randomPosition and update into it
- add is_expired to check if time ran out to buy spawned item

src/settings.py

@@ -41,10 +41,12 @@ ECTS_UPDATE_INTERVAL = 1000     # time in ms (1000 = 1 sec)
 BEER_BOTTLE_ECTS_VALUE = 2
 BEER_COST = 50
 
+
 # --- BUTTONS ---
 COLOR_BUTTON = (0, 255, 0)
 COLOR_BUTTON_HOVER = (200, 255, 0)
 
+
 # --- STARTSCREEN ---
 COLOR_STARTSCREEN_BACKGROUND = ((0, 0, 0))
 COLOR_STARTSCREEN_FONT_TITLE = (0, 255, 0)
@@ -55,6 +57,7 @@ COLOR_STARTSCREEN_FONT_LABEL = (0, 255, 255)
 COFFEE_COST = 30
 COFFEE_HEAL_VALUE = 30
 
+
 # --- TOWER ---
 TOWER_COST = 150
 PROJECTILE_DMG = 15
@@ -62,11 +65,13 @@ PROJECTILE_SPEED = 7
 COLOR_PROJECTILE = (200, 200, 0)
 TOWER_TIMER = 30000             # how long the tower stays and attack before it disappears
 
+
 # --- ITEM SPAWN TIMER ---
 ITEM_SPAWN_INTERVAL = 5000      # ms until a new item spawns
 ITEM_SHOPPING_TIMER = 10000     # how long you have time to buy items before they despawn
 ITEM_SIZE = 30
 
+
 # --- ZOMBIE ---
 ZOMBIE_EASY_HP = 30
 ZOMBIE_EASY_DMG = 3