YachtDice/Assets/Scripts/Shop/ShopModel.cs

using System;
using System.Collections.Generic;
using YachtDice.Economy;
using YachtDice.Inventory;
using YachtDice.Modifiers;

namespace YachtDice.Shop
{
    public class ShopModel
    {
        private readonly CurrencyBank currencyBank;
        private readonly InventoryModel inventoryModel;
        private readonly HashSet<string> purchasedPermanentIds = new();

        public event Action<ModifierData> OnItemPurchased;

        public ShopModel(CurrencyBank currencyBank, InventoryModel inventoryModel)
        {
            this.currencyBank = currencyBank;
            this.inventoryModel = inventoryModel;
        }

        public bool CanPurchase(ModifierData modifier)
        {
            if (modifier == null) return false;
            if (!currencyBank.CanAfford(modifier.ShopPrice)) return false;

            if (modifier.Durability == ModifierDurability.Permanent &&
                purchasedPermanentIds.Contains(modifier.Id))
                return false;

            return true;
        }

        public bool TryPurchase(ModifierData modifier)
        {
            if (!CanPurchase(modifier)) return false;

            if (!currencyBank.Spend(modifier.ShopPrice)) return false;

            if (modifier.Durability == ModifierDurability.Permanent)
                purchasedPermanentIds.Add(modifier.Id);

            inventoryModel.AddModifier(modifier);
            OnItemPurchased?.Invoke(modifier);
            return true;
        }

        public bool IsPermanentOwned(string modifierId) => purchasedPermanentIds.Contains(modifierId);

        public ShopItemState GetItemState(ModifierData modifier)
        {
            if (modifier == null) return ShopItemState.TooExpensive;

            if (modifier.Durability == ModifierDurability.Permanent &&
                purchasedPermanentIds.Contains(modifier.Id))
                return ShopItemState.Owned;

            if (!currencyBank.CanAfford(modifier.ShopPrice))
                return ShopItemState.TooExpensive;

            return modifier.Durability == ModifierDurability.LimitedUses
                ? ShopItemState.RepurchaseAvailable
                : ShopItemState.Available;
        }

        public void LoadPurchasedPermanentIds(IEnumerable<string> ids)
        {
            purchasedPermanentIds.Clear();
            if (ids != null)
                foreach (var id in ids) purchasedPermanentIds.Add(id);
        }

        public HashSet<string> GetPurchasedPermanentIds() => new(purchasedPermanentIds);
    }

    public enum ShopItemState
    {
        Available,
        TooExpensive,
        Owned,
        RepurchaseAvailable
    }
}