package de.podfetcher.feed;

import java.util.ArrayList;


import de.podfetcher.storage.*;
import android.content.Context;
import android.database.Cursor;
import android.util.Log;


/**
 * Singleton class
 * Manages all feeds, categories and feeditems
 *  
 *
 *  */
public class FeedManager {
	private static final String TAG = "FeedManager";
	
	private static FeedManager singleton;
	
	private ArrayList<Feed> feeds;
	private ArrayList<FeedCategory> categories;
	private DownloadRequester requester;	

	
	private FeedManager() {
		feeds = new ArrayList<Feed>();
		categories = new ArrayList<FeedCategory>();
		requester = DownloadRequester.getInstance();

	}
	
	public static FeedManager getInstance(){
		if(singleton == null) {
			singleton = new FeedManager();
		}
		return singleton;		
	}

	public void refreshAllFeeds(Context context) {
		Log.d(TAG, "Refreshing all feeds.");
		for(Feed feed : feeds) {
			requester.downloadFeed(context, feed);
		}
	}

	private void addNewFeed(Context context, Feed feed) {
		feeds.add(feed);
		feed.setId(setFeed(context, feed));
		for(FeedItem item : feed.getItems()) {
			setFeedItem(context, item);
		}
	}	
	

	/** Adds a new Feeditem if its not in the list */
	public void addFeedItem(Context context, FeedItem item) {
		PodDBAdapter adapter = new PodDBAdapter(context);
		// Search list for feeditem
		Feed feed = item.getFeed();
		FeedItem foundItem = searchFeedItemByLink(feed, item.getLink());
		if(foundItem != null) {
			// Update Information
			item.id = foundItem.id;
			foundItem = item;
			item.setRead(foundItem.isRead());
			adapter.setFeedItem(item);
		} else {
			feed.getItems().add(item);	
			item.id = adapter.setFeedItem(item);
		}
	}

	public void updateFeed(Context context, Feed newFeed) {
		// Look up feed in the feedslist
		Feed savedFeed = searchFeedByLink(newFeed.getLink());
		if(savedFeed == null) {
			Log.d(TAG, "Found no existing Feed with title " +  newFeed.getTitle() + ". Adding as new one.");
			// Add a new Feed
			addNewFeed(context, newFeed);
		}else {
			Log.d(TAG, "Feed with title " + newFeed.getTitle() + " already exists. Syncing new with existing one.");
			// Look for new or updated Items
			for(FeedItem item : newFeed.getItems()) {
				FeedItem oldItem = searchFeedItemByLink(savedFeed, item.getLink());
				if(oldItem != null) {
					FeedItem newItem = searchFeedItemByLink(newFeed, item.getLink());
					if(newItem != null) {
						newItem.setRead(oldItem.isRead());
					}
				}
			}
			newFeed.setId(savedFeed.getId());
			savedFeed = newFeed;
			setFeed(context, newFeed);	
		}

	}

	/** Get a Feed by its link */
	private Feed searchFeedByLink(String link) {
		for(Feed feed : feeds) {
			if(feed.getLink().equals(link)) {
				return feed;
			}
		}
		return null;
	}

	/** Get a FeedItem by its link */
	private FeedItem searchFeedItemByLink(Feed feed, String link) {
		for(FeedItem item : feed.getItems()) {
			if(item.getLink().equals(link)) {
				return item;
			}
		}
		return null;
	}

	/** Updates Information of an existing Feed */
	public long setFeed(Context context, Feed feed) {
		PodDBAdapter adapter = new PodDBAdapter(context);
		return adapter.setFeed(feed);
	}

	public long setFeedItem(Context context, FeedItem item) {
		PodDBAdapter adapter = new PodDBAdapter(context);
		return adapter.setFeedItem(item);
	}
	
	/** Updates information of an existing FeedImage */
	public long setFeedImage(Context context, FeedImage image) {
	    PodDBAdapter adapter = new PodDBAdapter(context);
	    return adapter.setImage(image);
	}

	/** Get a Feed by its id */
	public Feed getFeed(long id) {
		for(Feed f : feeds) {
			if(f.id == id) {
				return f;
			}
		}
		return null;
	}

	/** Get a Feed Image by its id */
	public FeedImage getFeedImage(long id) {
		for(Feed f : feeds) {
			FeedImage image = f.getImage();
			if(image != null && image.getId() == id) {
				return image;
			}
		}
		return null;
	}

	/** Get a Feed Item by its id and its feed*/
	public FeedItem getFeedItem(long id, Feed feed) {
			for(FeedItem item : feed.getItems()) {
				if(item.getId() == id) {
					return item;
				}
			}
		Log.w(TAG, "Couldn't find FeedItem with id " + id);
		return null;
	}
	
	/** Reads the database */
	public void loadDBData(Context context) {
		PodDBAdapter adapter = new PodDBAdapter(context);
		updateArrays(context);
	}
	
	
	public void updateArrays(Context context) {
		feeds.clear();
		categories.clear();
		extractFeedlistFromCursor(context);		
	}
	
	private void extractFeedlistFromCursor(Context context) {
		PodDBAdapter adapter = new PodDBAdapter(context);
		adapter.open();
		Cursor feedlistCursor = adapter.getAllFeedsCursor();
		if(feedlistCursor.moveToFirst()) {
			do {
				Feed feed = new Feed();
				
				feed.id = feedlistCursor.getLong(feedlistCursor.getColumnIndex(PodDBAdapter.KEY_ID));
				feed.setTitle(feedlistCursor.getString(feedlistCursor.getColumnIndex(PodDBAdapter.KEY_TITLE)));
				feed.setLink(feedlistCursor.getString(feedlistCursor.getColumnIndex(PodDBAdapter.KEY_LINK)));
				feed.setDescription(feedlistCursor.getString(feedlistCursor.getColumnIndex(PodDBAdapter.KEY_DESCRIPTION)));
				feed.setImage(adapter.getFeedImage(feedlistCursor.getLong(feedlistCursor.getColumnIndex(PodDBAdapter.KEY_IMAGE))));
				feed.file_url = feedlistCursor.getString(feedlistCursor.getColumnIndex(PodDBAdapter.KEY_FILE_URL));
				feed.download_url = feedlistCursor.getString(feedlistCursor.getColumnIndex(PodDBAdapter.KEY_DOWNLOAD_URL));
				
				// Get FeedItem-Object
				Cursor itemlistCursor = adapter.getAllItemsOfFeedCursor(feed);
				feed.setItems(extractFeedItemsFromCursor(context, itemlistCursor));
				
				feeds.add(feed);
			}while(feedlistCursor.moveToNext());
		}
		adapter.close();
	}
	
	private ArrayList<FeedItem> extractFeedItemsFromCursor(Context context, Cursor itemlistCursor) {
		ArrayList<FeedItem> items = new ArrayList<FeedItem>();
		PodDBAdapter adapter = new PodDBAdapter(context);
		adapter.open();
		if(itemlistCursor.moveToFirst()) {
			do {
				FeedItem item = new FeedItem();
				
				item.id = itemlistCursor.getLong(itemlistCursor.getColumnIndex(PodDBAdapter.KEY_ID));
				item.setTitle(itemlistCursor.getString(itemlistCursor.getColumnIndex(PodDBAdapter.KEY_TITLE)));
				item.setLink(itemlistCursor.getString(itemlistCursor.getColumnIndex(PodDBAdapter.KEY_LINK)));
				item.setDescription(itemlistCursor.getString(itemlistCursor.getColumnIndex(PodDBAdapter.KEY_DESCRIPTION)));
				item.setPubDate(itemlistCursor.getString(itemlistCursor.getColumnIndex(PodDBAdapter.KEY_PUBDATE)));
				item.setMedia(adapter.getFeedMedia(itemlistCursor.getLong(itemlistCursor.getColumnIndex(PodDBAdapter.KEY_MEDIA))));
				item.setRead((itemlistCursor.getInt(itemlistCursor.getColumnIndex(PodDBAdapter.KEY_READ)) > 0) ? true : false);
				
				items.add(item);
			} while(itemlistCursor.moveToNext());
		}
		adapter.close();
		return items;
	}

	public ArrayList<Feed> getFeeds() {
		return feeds;
	}
	
	 
	

}