package nl.primatras.backoffice.web.view;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import nl.primatras.backoffice.domain.Order;

import org.springframework.web.servlet.view.AbstractView;

import com.sun.syndication.feed.synd.SyndContent;
import com.sun.syndication.feed.synd.SyndContentImpl;
import com.sun.syndication.feed.synd.SyndEntry;
import com.sun.syndication.feed.synd.SyndEntryImpl;
import com.sun.syndication.feed.synd.SyndFeed;
import com.sun.syndication.feed.synd.SyndFeedImpl;
import com.sun.syndication.io.SyndFeedOutput;

/**
 * Class to create a Rss feed. The feed is created using the 
 * <a href="http://wiki.java.net/bin/view/Javawsxml/Rome">Rome</a> Library.
 * This class is largely based on the servlet example from their wiki site.
 * By default this class uses the atom_0.3 rss version, but if you specify 
 * a parameter 'type' with another rss version that is supported by Rome, it
 * will create an rss feed based on that version.
 * 
 * @author Jettro Coenradie
 */
public class RssOrderView extends AbstractView {
	private static final String DEFAULT_FEED_TYPE = "atom_0.3";
    private static final String FEED_TYPE = "type";
    private static final String ORDER_COLLECTION = "orders";

    private String orderOverviewView;
    
    /**
     * Default constructor
     */
    public RssOrderView() {
    	setContentType("application/xml; charset=UTF-8");
		setOrderOverviewView("showOrderOverview.html");
    }
    
	@Override
	protected void renderMergedOutputModel(Map model,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
    	List<Order> orders = (List)model.get(ORDER_COLLECTION);
    	
    	String baseUrl = "http://"+ request.getServerName() +":"+ request.getServerPort() +
    		request.getContextPath() + "/";
    	
        SyndFeed feed = getFeed(orders,baseUrl);
        String feedType = request.getParameter(FEED_TYPE);
        feedType = (feedType!=null) ? feedType : DEFAULT_FEED_TYPE;
        feed.setFeedType(feedType);

        response.setContentType(getContentType());
        SyndFeedOutput output = new SyndFeedOutput();
        output.output(feed,response.getWriter());
	}
	
	/**
	 * Creates a list with entries from the provided list of orders
	 * @param orders
	 * @param contextPath
	 * @return
	 */
	private SyndFeed getFeed(List<Order> orders,String contextPath) { 
		SyndFeed feed = new SyndFeedImpl();
		feed.setAuthor(getMessageSourceAccessor().getMessage("order.feed.author"));
		feed.setTitle(getMessageSourceAccessor().getMessage("order.feed.title"));
		feed.setDescription(getMessageSourceAccessor().getMessage("order.feed.description"));
		feed.setLink(contextPath);
		
		List<SyndEntry> entries = new ArrayList<SyndEntry>();
		
		
		for (Order order : orders) {
			String entryTitle = order.getCustomer().getLastname();
			String entryLink = contextPath + getOrderOverviewView() + 
					"?id=" + order.getId();
			String entryDescription = order.toString(); 

			entries.add(createEntry(entryTitle,entryLink,entryDescription,order.getCreatedate()));
		}
		
		feed.setEntries(entries);
		return feed;
	}
	
	/**
	 * Creates an entry from the provided data
	 * @param title
	 * @param link
	 * @param description
	 * @param createDate
	 * @return the new create entry
	 */
	private SyndEntry createEntry (String title, String link, String description,
			Date createDate) {
		SyndEntry entry = new SyndEntryImpl();
		entry.setTitle(title);
		entry.setLink(link);
		entry.setPublishedDate(createDate);
		
		SyndContent entryDescription = new SyndContentImpl();
		entryDescription.setType("text/plain");
		entryDescription.setValue(description);
		
		entry.setDescription(entryDescription);
		
		return entry;
	}

	public String getOrderOverviewView() {
		return orderOverviewView;
	}

	public void setOrderOverviewView(String orderOverviewView) {
		this.orderOverviewView = orderOverviewView;
	}
}