Implement armor system

Add all armor types and handle base/bonus AC. Implement the generation
of enchanted and cursed armor. Handle cursed armor and identification
mechanics. Review and refine armor-related actions.

game/action.py

@@ -103,6 +103,9 @@ def perform(self, actor: Actor, level: Level, log: MessageLog) -> bool:
         if level.get_item_at(actor.x, actor.y):
             log.append("There is something there already.")
             return False
+        if self.item.cursed and actor.inventory.is_equipped(self.item):
+            log.append("You can't. It appears to be cursed.")
+            return False
         actor.inventory.remove_item(self.item)
         self.item.x, self.item.y = actor.x, actor.y
         level.entities.add(self.item)
@@ -142,6 +145,7 @@ def __init__(self, item: Item):
     def perform(self, actor: Actor, level: Level, log: MessageLog) -> bool:
         assert isinstance(actor, Player)
         actor.inventory.armor_slot = self.item
+        self.item.identified = True
         log.append(f"You are now wearing {self.item}.")
         return True
 
@@ -168,6 +172,9 @@ class TakeOffAction(Action):
     def perform(self, actor: Actor, level: Level, log: MessageLog) -> bool:
         assert isinstance(actor, Player)
         if armor := actor.inventory.armor_slot:
+            if armor.cursed:
+                log.append("You can't. It appears to be cursed.")
+                return False
             actor.inventory.armor_slot = None
             log.append(f"You used to be wearing {armor}.")
             return True

game/combat.py

@@ -29,10 +29,16 @@ def __post_init__(self) -> None:
         self.hp = self.max_hp
 
 
-@dataclass(frozen=True, slots=True)
+@dataclass(eq=False, slots=True, kw_only=True)
 class Armor:
-    # armor class
-    ac: int
+    # base armor class
+    base_ac: int
+    # armor class bonus
+    plus_ac: int = 0
+
+    @property
+    def ac(self) -> int:
+        return self.base_ac - self.plus_ac
 
 
 @dataclass(frozen=True, slots=True)

game/entity.py

@@ -35,6 +35,8 @@ class Player(Actor):
 
 @dataclass(eq=False, slots=True, kw_only=True)
 class Item(Entity):
+    cursed: bool = False
+    identified: bool = False
     gold: int | None = None
     consumable: Consumable | None = None
 
@@ -46,6 +48,12 @@ def __str__(self) -> str:
 class ArmorItem(Item):
     armor: Armor
 
+    def __str__(self) -> str:
+        if self.identified:
+            return f"{self.armor.plus_ac:+d} {self.name} [armor class {self.armor.ac}]"
+        else:
+            return self.name
+
 
 @dataclass(eq=False, slots=True, kw_only=True)
 class WeaponItem(Item):

game/game_loop.py

@@ -21,7 +21,9 @@
 def new_game() -> tuple[Player, Level, MessageLog]:
     level = generate_level(map_width, map_height, 1)
     inventory = Inventory()
-    armor = ArmorItem(x=0, y=0, glyph=Glyph.ARMOR, name='+1 ring mail', armor=Armor(ac=6))
+    armor = ArmorItem(
+        x=0, y=0, glyph=Glyph.ARMOR, name="ring mail", armor=Armor(base_ac=7, plus_ac=+1), identified=True
+    )
     inventory.add_item(armor)
     inventory.armor_slot = armor
     weapon = WeaponItem(x=0, y=0, glyph=Glyph.WEAPON, name='+1,+1 mace',

game/inventory.py

@@ -43,3 +43,7 @@ def remove_item(self, item: Item) -> None:
         if item is self.weapon_slot:
             self.weapon_slot = None
         self.items.remove(item)
+
+    def is_equipped(self, item: Item) -> bool:
+        assert item in self.items
+        return item in (self.armor_slot, self.weapon_slot)

game/items.py

@@ -38,8 +38,14 @@ def spawn(self, x: int, y: int) -> Item:
 ]
 
 armor_types = [
-    ItemType(20, Glyph.ARMOR, 'leather armor', Armor(ac=8)),
-    ItemType(12, Glyph.ARMOR, 'chain mail', Armor(ac=5)),
+    ItemType(20, Glyph.ARMOR, "leather armor", Armor(base_ac=8)),
+    ItemType(15, Glyph.ARMOR, "ring mail", Armor(base_ac=7)),
+    ItemType(15, Glyph.ARMOR, "studded leather armor", Armor(base_ac=7)),
+    ItemType(13, Glyph.ARMOR, "scale mail", Armor(base_ac=6)),
+    ItemType(12, Glyph.ARMOR, "chain mail", Armor(base_ac=5)),
+    ItemType(10, Glyph.ARMOR, "splint mail", Armor(base_ac=4)),
+    ItemType(10, Glyph.ARMOR, "banded mail", Armor(base_ac=4)),
+    ItemType(5, Glyph.ARMOR, "plate mail", Armor(base_ac=3)),
 ]
 
 weapon_types = [
@@ -61,7 +67,7 @@ def get_item_types(self) -> tuple[list[ItemType], list[int]]:
 item_categories = [
     ItemCategory(27, potion_types),
     ItemCategory(27, scroll_types),
-    ItemCategory(9, armor_types),
+    ItemCategory(8, armor_types),
     ItemCategory(9, weapon_types),
 ]
 

game/procgen.py

@@ -4,7 +4,7 @@
 import random
 
 from game.constants import Glyph, Tile
-from game.entity import Item
+from game.entity import ArmorItem, Item
 from game.items import get_item_categories
 from game.level import Level
 from game.monsters import eligible_monsters
@@ -259,6 +259,13 @@ def place_item(all_rooms: list[Room | Junction], level: Level) -> None:
     item_types, weights = category.get_item_types()
     item_type = rng.choices(item_types, weights).pop()
     item = item_type.spawn(x, y)
+    if isinstance(item, ArmorItem):
+        r = rng.random()
+        if r < 0.20:
+            item.cursed = True
+            item.armor.plus_ac = -rng.randint(1, 3)
+        elif r < 0.28:
+            item.armor.plus_ac = +rng.randint(1, 3)
     level.entities.add(item)
 
 

game/state.py

@@ -75,6 +75,9 @@ def event(self, event: tcod.event.Event, player: Player, level: Level, log: Mess
             case Command.WIELD:
                 return UseItem(glyph=Glyph.WEAPON)
             case Command.WEAR:
+                if player.inventory.armor_slot:
+                    log.append("You are already wearing some. You'll have to take it off first.")
+                    return Play()
                 return UseItem(glyph=Glyph.ARMOR)
             case Command.TAKEOFF:
                 action = TakeOffAction()