Configuration

USTRUCT(BlueprintType)
struct FMerchantConfig
{
    // Stock Management
    bool bHasStock = true;                      // Finite vs infinite stock

    // Buying Behavior
    bool bBuysAnything = false;                 // Accepts all items
    bool bHasBuyList = false;                   // Uses whitelist

    // Replenishment
    bool bReplenishOnBuyback = true;            // Sold items restock merchant

    // Pricing
    float MarketFeePercent = 0.0f;              // Transaction fee (0-100%)
    float BuybackPercent = 50.0f;               // Buy price % of base value

    // Currency
    UItemDataAsset* AcceptedCurrency;           // Currency item (e.g., Gold)

    // Interaction
    float MaxInteractionDistance = 300.0f;      // Max distance in units
    float QuoteExpirationSeconds = 30.0f;       // Quote validity duration
};

USTRUCT(BlueprintType)
struct FStockItem
{
    UItemDataAsset* ItemData;                   // Item reference
    int32 MaxStock = 100;                       // Maximum quantity
    int32 CurrentStock = 100;                   // Current available

    // Pricing Overrides
    float UnitPriceOverride = -1.0f;            // Custom sell price (-1 = use item's base)
    float BuyPriceOverridePercent = -1.0f;      // Custom buyback % (-1 = use vendor default)

    // Replenishment
    EReplenishMode ReplenishMode = UseVendorDefault;
};

enum class EReplenishMode : uint8
{
    UseVendorDefault,    // Follow Config.bReplenishOnBuyback
    AlwaysReplenish,     // Always add sold items to stock
    NeverReplenish       // Act as item sink (good for trash/recycler NPCs)
};