pet-inventory-management

name	pet-inventory-management
description	Implementation pattern for adding pet inventory management (give/take/equip/unequip items to pets)
source	auto-skill
extracted_at	2026-06-11T15:24:51.878Z

Pet Inventory Management Implementation Pattern

This skill documents the approach for implementing pet inventory management in Remixed Dungeon, allowing players to give, take, equip, and unequip items on their pets.

Architecture Overview

The implementation follows the existing codebase patterns:

• Centralized Manager: PetInventoryManager for all pet inventory operations
• UI Window: WndPetBag extending WndBag for pet inventory display
• Action Integration: New CommonActions constants for pet-specific actions
• Pet Selection: WndPetSelect for choosing among multiple pets

Key Design Principles

1. Leverage Existing Systems

• Pets already have Belongings (backpack + equipment slots) via Char.getBelongings()
• Serialization handled by existing Char.storeInBundle()/restoreFromBundle()
• Equipment logic reused from Belongings.equip()/unequip()/setItemForSlot()
• UI patterns from WndBag/ItemButton/WndItem

2. Action Flow

Hero taps pet → Order menu → [Move, Attack, Inventory, Expel]
                          ↓
                  WndPetSelect (if >1 pet)
                          ↓
                  WndPetBag (pet's inventory)
                          ↓
                  Item tap → WndItem with pet actions:
                  [Give to Pet, Take from Pet, Equip on Pet, Unequip from Pet]

3. Core Components

PetInventoryManager.java (New)

Static utility class with methods:

• giveItemToPet(Hero hero, Mob pet, Item item) - Transfer from hero to pet
• takeItemFromPet(Hero hero, Mob pet, Item item) - Transfer from pet to hero
• equipItemOnPet(Mob pet, EquipableItem item, Belongings.Slot slot) - Equip on pet
• unequipItemFromPet(Mob pet, EquipableItem item) - Unequip from pet
• canEquipOnPet(Mob pet, EquipableItem item, Belongings.Slot slot) - Validation
• openPetInventory(Hero hero, Mob pet) - Opens WndPetBag

WndPetBag.java (New - extends WndBag)

• Constructor takes Mob pet instead of Belongings
• Shows pet's equipped items + backpack
• Action buttons for pet-specific operations
• Read-only mode for non-owners (future multiplayer)

WndPetSelect.java (New)

• Lists all hero's pets with name, HP, entity kind
• Tap to select → opens WndPetBag for that pet

CommonActions.java (Extend)

public static final String AC_PET_INVENTORY = "PetInventory_ACOpen";
public static final String AC_GIVE_TO_PET = "PetInventory_ACGiveToPet";
public static final String AC_TAKE_FROM_PET = "PetInventory_ACTakeFromPet";
public static final String AC_EQUIP_ON_PET = "PetInventory_ACEquipOnPet";
public static final String AC_UNEQUIP_FROM_PET = "PetInventory_ACUnequipFromPet";

CharUtils.java (Extend actions())

if (target.isPet() && target.getOwnerId() == hero.getId()) {
    actions.add(CommonActions.AC_PET_INVENTORY);
}

OrderCellSelector.java (Extend)

Add "Inventory" option alongside Move/Attack in the cell selection prompt.

4. Item Action Integration

In Item.actions(Char hero) or EquipableItem.actions(Char hero):

• If item in hero's backpack and hero has pets → add "Give to Pet"
• If item in pet's inventory → add "Take from Pet", "Equip on Pet", "Unequip from Pet"
• Use PetInventoryManager for actual operations

5. Validation Rules

• Distance: Hero and pet must be adjacent or same cell
• Pet State: Pet must be alive and isPet() == true
• Ownership: pet.getOwnerId() == hero.getId()
• Equipment: Check STR requirements, slot compatibility for pet
• Capacity: Pet backpack has 18 slots (same as hero)

6. Item Ownership Transfer

// Give to pet
item.detach(hero.getBelongings().backpack);
item.setOwner(pet);
pet.getBelongings().collect(item);

// Take from pet
item.detach(pet.getBelongings().backpack);
item.setOwner(hero);
hero.getBelongings().collect(item);

7. Equipment on Pets

Pets use same Belongings.Slot enum:

• WEAPON, LEFT_HAND, ARMOR, ARTIFACT, LEFT_ARTIFACT
• Belongings.equip() / unequip() work identically
• Pet stats (damage, DR) automatically updated via existing systems

8. Lua/Modding Support

Add @LuaInterface annotations to PetInventoryManager methods:

@LuaInterface
public static void giveItemToPet(Hero hero, Mob pet, Item item) { ... }

@LuaInterface
public static void openPetInventory(Hero hero, Mob pet) { ... }

Implementation Order

1. PetInventoryManager - Core logic, no UI dependencies
2. CommonActions - Action constants
3. WndPetBag - Pet inventory UI
4. WndPetSelect - Pet selection (if needed)
5. CharUtils/OrderCellSelector - Integration points
6. Item/EquipableItem - Pet-specific actions
7. Testing - Various pet types, items, edge cases

Edge Cases Handled

• Cursed Items: Cannot unequip if cursed (same as hero)
• Stackable Items: Transfer full stack or partial
• Bags: Pets can have bags (potion belt, quiver, etc.)
• Pet Death: Items drop on death (existing Mob.dropAll())
• Level Transition: Pets follow hero, belongings persist
• Multiple Pets: Selection window handles this

Testing Checklist

• Give item from hero to pet backpack
• Take item from pet to hero backpack
• Equip weapon/armor/ring on pet
• Unequip item from pet
• Cursed item handling on pet
• Stackable item partial transfer
• Pet with bags (potion belt, etc.)
• Multiple pets - selection works
• Save/load preserves pet inventory
• Pet death drops items
• Level transition preserves items
• Mod/Lua API access works