import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.Vector;

import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.google.gson.Gson;

import basar.domain.BasarFacade;
import basar.domain.BasarFactory;
import basar.domain.Seller;

public class CashPointServlet extends HttpServlet {

	private static final String CUSTOMERS_HISTORY_ACTION = "/history";

	private static final String CUSTOMERS_ACTION = "/customers";

	private static final String SAVE_CUSTOMER_ACTION = "/saveCustomer";

	private static final String DELETE_CUSTOMER_ACTION = "/deleteCustomer";

	private static final long serialVersionUID = 1L;

	private Gson gson = new Gson();

	private BasarFacade basar;

	@Override
	public void init() throws ServletException {
		basar = BasarFactory.instance.createBasarFacade();
	}

	@Override
	public void destroy() {
		basar = null;
	}

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		String path = req.getPathInfo();
		if (path.equals(SAVE_CUSTOMER_ACTION)) {
			saveCustomerAction(req, resp);
		}
	}

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		String path = req.getPathInfo();
		if (path.equals(CUSTOMERS_ACTION)) {
			getCustomersAction(req, resp);
		} else if (path.equals(CUSTOMERS_HISTORY_ACTION)) {
			getCustomersHistoryAction(req, resp);
		}
	}

	@Override
	protected void doDelete(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		String path = req.getPathInfo();
		if (path.equals(DELETE_CUSTOMER_ACTION)) {
			deleteCustomerAction(req, resp);
		}
	}

	/** Read a HTTP Cookie */
	protected void getCustomersHistoryAction(HttpServletRequest req,
			HttpServletResponse resp) throws IOException {
		Cookie sellerHistoryCookie = findHistoryCookie(req);
		if (sellerHistoryCookie != null) {
			List<Seller> sellers = fromJsonString(sellerHistoryCookie
					.getValue());
			for (Seller seller : sellers) {
				PrintWriter writer = resp.getWriter();
				writer.println(seller);
			}
		}
	}

	/** Set and reset a Cookie */
	protected void writeHistory(HttpServletRequest req, HttpServletResponse resp, Seller seller) {
		Cookie sellerHistoryCookie = findHistoryCookie(req);
		if (sellerHistoryCookie == null) {
			List<Seller> sellerList = new Vector<Seller>();
			sellerList.add(seller);
			sellerHistoryCookie = new Cookie("sellerHistory", toJsonString(sellerList));
		}
		else {
			List<Seller> sellerList = fromJsonString(sellerHistoryCookie.getValue());
			sellerList.add(seller);
			sellerHistoryCookie.setValue(toJsonString(sellerList));
		}
		resp.addCookie(sellerHistoryCookie);
	}

	protected Cookie findHistoryCookie(HttpServletRequest req) {
		Cookie[] cookies = req.getCookies();
		if (cookies != null) {
			for (Cookie cookie : cookies) {
				if (cookie.getName().equals("sellerHistory")) {
					return cookie;
				}
			}
		}
		return null;
	}

	protected String toJsonString(List<Seller> sellerList) {
		return gson.toJson(sellerList);
	}

	protected List<Seller> fromJsonString(String sellersJson) {
		Seller[] sellers = gson.fromJson(sellersJson, Seller[].class);
		List<Seller> sellerList = new ArrayList<Seller>();
		sellerList.addAll(Arrays.asList(sellers));
		return sellerList;
	}

	protected void getCustomersAction(HttpServletRequest req,
			HttpServletResponse resp) throws IOException {
		Collection<Seller> sellerList = basar.getSellerList();
		Gson gson = new Gson();
		String json = gson.toJson(sellerList);
		resp.getWriter().append(json);
	}

	protected void saveCustomerAction(HttpServletRequest req,
			HttpServletResponse resp) throws IOException {
		Long basarNumber = Long.valueOf(req.getParameter("basarNumber"));
		String firstName = req.getParameter("firstName");
		String lastName = req.getParameter("lastName");
		Seller seller = basar.getSeller(basarNumber);
		boolean isNewSeller = false;
		if (seller == null) {
			seller = new Seller();
			seller.setBasarNumber(basarNumber);
			isNewSeller = true;
		}
		seller.setName(lastName);
		seller.setFirstname(firstName);
		if (isNewSeller) {
			basar.insertSeller(seller);
		} else {
			basar.updateSeller(seller);
		}
		writeHistory(req, resp, seller);
		resp.sendRedirect("../customer-overview.html");
	}

	protected void deleteCustomerAction(HttpServletRequest req,
			HttpServletResponse resp) {
		Long basarNumber = Long.valueOf(req.getParameter("basarNumber"));
		Seller seller = basar.getSeller(basarNumber);
		if (seller != null) {
			basar.deleteSeller(seller);
		}
	}

}