package ee.ut.math.tvt.salessystem.dao;

import ee.ut.math.tvt.salessystem.SalesSystemException;
import ee.ut.math.tvt.salessystem.dataobjects.SoldItem;
import ee.ut.math.tvt.salessystem.dataobjects.StockItem;
import ee.ut.math.tvt.salessystem.dataobjects.PurchaseItem;

import java.time.LocalDate;
import java.util.ArrayList;
import java.util.List;

public class InMemorySalesSystemDAO implements SalesSystemDAO {

    private final List<StockItem> stockItemList;
    private final List<SoldItem> soldItemList;
    private final List<PurchaseItem> purchaseList;


    public InMemorySalesSystemDAO() {
        this.stockItemList = new ArrayList<StockItem>();
        this.soldItemList = new ArrayList<>();
        this.purchaseList = new ArrayList<>();
    }

    @Override
    public void beginTransaction() {
    }

    @Override
    public void rollbackTransaction() {
    }

    @Override
    public void commitTransaction() {
    }

    @Override
	public void addStockItem(String strBarcode, String name, String strPrice, String strQuantity) throws SalesSystemException{
		try {
			long id = Integer.parseInt(strBarcode);
			double price = Long.parseLong(strPrice);
			int quantity = Integer.parseInt(strQuantity);

			StockItem item = findStockItem(id);
			if (id < 1 || id > 1000)
				throw new SalesSystemException("Barcode is less than 1 or more than 1000!");
			if (name.length() < 3 || name.length() > 30)
				throw new SalesSystemException("Item name length is less than 3 or more than 30!");
			if (price < 0 || price > 100000)
				throw new SalesSystemException("Price must be between 0 to 100000!");
			if (quantity > 1000 || quantity < 0)
				throw new SalesSystemException("Quantity is less than 1 or more than 1000");

			//checks if item exists and if so, updates it's quantity
			if (item != null) {
				increaseStockItem(item, quantity);
			} else {
				StockItem newItem = new StockItem(id, name, "", price, quantity);
				saveStockItem(newItem);
			}
		}
		catch(SalesSystemException e) {
			throw new SalesSystemException(e.getMessage());
		}
		catch(Exception e) {
			throw new SalesSystemException("You entered invalid input!");
		}
	}

    @Override
    public void increaseStockItem(StockItem item, int quantity) {
    	item.setQuantity(item.getQuantity() + quantity);
    }

    @Override
	public void decreaseStockItem(StockItem item, int quantity) {
		item.setQuantity(item.getQuantity() - quantity);
	}

    @Override
	public void saveStockItem(StockItem item) {
    	stockItemList.add(item);
	}

    /**sold items*/
    @Override
    public void saveSoldItem(SoldItem item) {
        soldItemList.add(item);
    }

	@Override
	public List<SoldItem> getSoldItems() {
		return soldItemList;
	}


	@Override
	public void increaseSoldItem(SoldItem item, int quantity) {
		item.setQuantity(item.getQuantity() + quantity);
	}


    @Override
    public List<StockItem> findStockItems() {
        return stockItemList;
    }

    @Override
    public StockItem findStockItem(long id) {
        for (StockItem item : stockItemList) {
            if (item.getId() == id)
                return item;
        }
        return null;
    }

    /**purchase list*/
	@Override
	public void savePurchaseList(List<SoldItem> items) {
		purchaseList.add(new PurchaseItem(items));
	}

	@Override
	public List<PurchaseItem> getPurchaseList(LocalDate startDate, LocalDate endDate, int itemsAmount) {
		return purchaseList;
	}
}