using UIWidgets;

namespace UIWidgetsSamples.Shops
{
	public class Trader
	{
		private int money;

		private ObservableList<Item> inventory = new ObservableList<Item>();

		public float PriceFactor = 1f;

		public bool DeleteIfEmpty = true;

		public int Money
		{
			get
			{
				return money;
			}
			set
			{
				if (money == -1)
				{
					MoneyChanged();
					return;
				}
				money = value;
				MoneyChanged();
			}
		}

		public ObservableList<Item> Inventory
		{
			get
			{
				return inventory;
			}
			set
			{
				if (inventory != null)
				{
					inventory.OnChange -= ItemsChanged;
				}
				inventory = value;
				if (inventory != null)
				{
					inventory.OnChange += ItemsChanged;
				}
				ItemsChanged();
			}
		}

		public event OnItemsChange OnItemsChange;

		public event OnMoneyChange OnMoneyChange;

		public Trader(bool deleteIfEmpty = true)
		{
			DeleteIfEmpty = deleteIfEmpty;
			inventory.OnChange += ItemsChanged;
		}

		private void ItemsChanged()
		{
			if (this.OnItemsChange != null)
			{
				this.OnItemsChange();
			}
		}

		private void MoneyChanged()
		{
			if (this.OnMoneyChange != null)
			{
				this.OnMoneyChange();
			}
		}

		public void Sell(IOrder order)
		{
			if (order.OrderLinesCount() != 0)
			{
				Inventory.BeginUpdate();
				order.GetOrderLines().ForEach(SellItem);
				Inventory.EndUpdate();
				Money += order.Total();
			}
		}

		private void SellItem(IOrderLine orderLine)
		{
			int count = orderLine.Count;
			orderLine.Item.Count -= count;
			if (DeleteIfEmpty && orderLine.Item.Count == 0)
			{
				Inventory.Remove(orderLine.Item);
			}
		}

		public void Buy(IOrder order)
		{
			if (order.OrderLinesCount() != 0)
			{
				Inventory.BeginUpdate();
				order.GetOrderLines().ForEach(BuyItem);
				Inventory.EndUpdate();
				Money -= order.Total();
			}
		}

		private void BuyItem(IOrderLine orderLine)
		{
			Item item = Inventory.Find((Item x) => x.Name == orderLine.Item.Name);
			int count = orderLine.Count;
			if (item == null)
			{
				Inventory.Add(new Item(orderLine.Item.Name, count));
			}
			else
			{
				item.Count += count;
			}
		}

		public bool CanBuy(IOrder order)
		{
			return Money == -1 || Money >= order.Total();
		}
	}
}