Inventory Management

Characters have a bag for carrying items and equipment slots for wearing them.

Bag System

The bag uses a grid-based layout:

InventoryGrid

interface InventoryGrid {
  width: number;   // Default: 10
  height: number;  // Default: 10
  items: GridItem[];
}

interface GridItem {
  itemId: string;
  x: number;       // Left position
  y: number;       // Top position
  width: number;   // From base type
  height: number;  // From base type
}

Operations

Operation	Description
GetBagGrid	Get grid layout with positions
GetBagItems	Get full item details
MoveBagItem	Move item to new position

Collision Detection

Items cannot overlap. The grain validates positions:

public async Task<bool> MoveBagItemAsync(Guid itemId, int newX, int newY)
{
    var item = _state.BagItems[itemId];
    
    // Check bounds
    if (newX + item.Width > GridWidth || newY + item.Height > GridHeight)
        return false;
    
    // Check collision with other items
    foreach (var other in _state.BagItems.Values)
    {
        if (other.ItemId != itemId && Overlaps(newX, newY, item, other))
            return false;
    }
    
    // Move successful
    UpdatePosition(itemId, newX, newY);
    return true;
}

Equipment Slots

Characters have 10 equipment slots:

EquipmentSlot Enum

enum EquipmentSlot {
  Head = 0,
  Body = 1,
  Gloves = 2,
  Boots = 3,
  MainHand = 4,
  OffHand = 5,
  Amulet = 6,
  Ring1 = 7,
  Ring2 = 8,
  Belt = 9
}

Equip Operation

EquipResult

interface EquipResult {
  success: boolean;
  swappedItem?: Item;      // Item that was in the slot
  errorMessage?: string;   // Why equip failed
}

Stash Tabs

Account stash is shared across characters (per season):

Operations

Operation	Description
GetTabsAsync	List all stash tabs
GetTabItemsAsync	Get items in a tab
AddItemAsync	Add item to stash
RemoveItemAsync	Take item from stash
TransferItemAsync	Move between tabs

Character Stats

Stats are calculated from base stats + equipment bonuses:

interface CharacterStats {
  baseStats: Record<string, number>;    // Without equipment
  totalStats: Record<string, number>;   // With equipment
  bonuses: StatBonus[];                 // Breakdown
}

interface StatBonus {
  source: string;     // Item name
  slot: EquipmentSlot;
  stat: string;
  value: number;
}

Calculation Flow