package dk.thoerup.traininfo.provider;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.URLEncoder;
import java.util.Collections;
import java.util.Comparator;
import java.util.LinkedList;

import org.simpleframework.xml.Serializer;
import org.simpleframework.xml.core.Persister;

import android.content.Context;
import android.location.Location;
import android.util.Log;
import dk.thoerup.android.traininfo.common.StationBean;
import dk.thoerup.android.traininfo.common.StationEntry;
import dk.thoerup.genericjavautils.HttpUtil;
import dk.thoerup.traininfo.util.DownloadUtil;
import dk.thoerup.traininfo.util.IntSet;
import dk.thoerup.traininfo.util.XmlUtil;

public class OfflineStationProvider implements StationProvider {
	
	StationBean stations = new StationBean();

	boolean statsByNameSend = false;

	public boolean hasStations() {
		return (stations != null && stations.entries.size() > 0);
	}
	

	public boolean loadStations(Context context) throws Exception {
		long start = System.currentTimeMillis();
		
		StationBean tmpStations = new StationBean();
		
		File parent = context.getFilesDir();
		File stationsFile = new File(parent, "stations.bin");
		
		if (!stationsFile.exists())
			return false;
		
		/*int size = (int) stationsFile.length();
		byte data[] = new byte[size];
		
		RandomAccessFile raf = new RandomAccessFile(stationsFile, "r");
		raf.readFully(data);
		
		Serializer serializer = new Persister();
		stations = serializer.read(StationBean.class,  new String(data, "ISO-8859-1") );*/
		
		

		ObjectInputStream in = new ObjectInputStream( new FileInputStream(stationsFile) );

		int length = in.readInt(); // first field is the length
		
		for (int i=0; i<length; i++) { 				
			StationEntry entry = (StationEntry) in.readObject();
			updateSearchStrings(entry);
			tmpStations.entries.add( entry );
		}
		
		in.close();

		stations = tmpStations; // når indlæsningen er ok skifter vi over
		
		Log.e("OFFLINE", "loaded" + tmpStations.entries.size());
		logElapsedTime(start, "loadStations");
		
		return true;
	}
	
	public void updateSearchStrings(StationEntry entry) {		
		entry.nameLower = entry.getName().toLowerCase();
		entry.nameInternational = entry.nameLower.replace("æ", "ae").replace("ø", "oe").replace("å", "aa");
	}
	
	public void downloadStations(Context context) throws Exception {
		File parent = context.getFilesDir();
		File stationsFile = new File(parent, "stations.bin");

		long start = System.currentTimeMillis();
		byte data[] = HttpUtil.getContent(XmlUtil.SERVICE_BASE + "/LocateStations?dump=1", 5000);
		logElapsedTime(start, "download XML");
		
		
		Serializer serializer = new Persister();		
		
		start = System.currentTimeMillis();
		StationBean tmpStations = serializer.read(StationBean.class,  new String(data, "ISO-8859-1") );
		logElapsedTime(start, "parse XML");
		
		
		ObjectOutputStream out = new ObjectOutputStream( new FileOutputStream(stationsFile) );
		Log.e("OFFLINE", "data size" + data.length);
		
		out.writeInt( tmpStations.entries.size() ); //start with writing the length of the dataset
		
		for (StationEntry entry : tmpStations.entries) {
			updateSearchStrings( entry ); //prepare name fields for byName search
			out.writeObject(entry);
		}
		
		out.close();
		
		stations = tmpStations; // når alt er ok skifter vi over til ny udgave
	}
	
	

	@Override
	public void purgeOldEntries() {
	}

	Comparator<StationEntry> distanceComparator = new Comparator<StationEntry>() {
		@Override
		public int compare(StationEntry object1, StationEntry object2) {
			if (object1.getCalcdist() == object2.getCalcdist()) 					
				return 0;
			
			if (object1.getCalcdist() > object2.getCalcdist())
				return 1;
			else
				return -1;
		}		
	};
	
	@Override
	public StationBean lookupStationsByLocation(Location location) {
		
		statsByLocation(location);
		
		long start = System.currentTimeMillis();
		Location tmpLoc = new Location("GPS");
		
		LinkedList<StationEntry> entries = new LinkedList<StationEntry>() ;
		
		for (StationEntry entry : stations.entries) {
			tmpLoc.setLatitude(entry.getLatitude());
			tmpLoc.setLongitude(entry.getLongitude());
			
			int distance = (int) location.distanceTo(tmpLoc);
			
			if (entries.size() <8 || entries.getLast().getCalcdist() > distance) {
				entry.setCalcdist(distance);
				
				if (entries.size() == 8)
					entries.removeLast();
				
				entries.addLast(entry);
				
				Collections.sort( entries, distanceComparator);
			}			
		}
		
		logElapsedTime(start, "location_stage1");
		
		Collections.sort( entries, distanceComparator);
		
		StationBean tmpStations = new StationBean();
		for (int i = 0; i<8 && i<entries.size(); i++) {
			tmpStations.entries.add( entries.get(i) );
		}
		
		logElapsedTime(start, "location");
		return tmpStations;
	}
	
	private void logElapsedTime(long start, String method) {
		long now = System.currentTimeMillis();
		
		Log.i("TrainInfo", "Search by " + method + " elapsed " + (now-start) );
	}

	@Override
	public StationBean lookupStationsByName(String name) {
	
		statsByName(name);	
		
		long start = System.currentTimeMillis();
		
		name = name.toLowerCase();
		StationBean tmpStations = new StationBean();
		for (StationEntry entry : stations.entries) {
			if (entry.nameLower.startsWith(name) || entry.nameInternational.startsWith(name) ) {
				tmpStations.entries.add(entry);
			}
			
			for(String alias : entry.getAliases()) {
				if (alias.startsWith(name)) {
					tmpStations.entries.add(entry);	
				}
			}
		}
		logElapsedTime(start, "name");				
		return tmpStations;
	}

	@Override
	public StationBean lookupStationsByIds(String ids) {
		statsByIds(ids);
		
		IntSet idset = new IntSet();
		idset.fromString(ids);
		
		StationBean tmpStations = new StationBean();
		for (StationEntry entry : stations.entries) {
			if (idset.contains( entry.getId() ) ) {
				tmpStations.entries.add(entry);
			}
		}
		
		return tmpStations;
	}
	

	private void statsByLocation(Location location) {
		double lat = XmlStationProvider.roundToPlaces(location.getLatitude(), 4);
		double lng = XmlStationProvider.roundToPlaces(location.getLongitude(), 4);
		
		final String url = XmlUtil.SERVICE_BASE + "/LocateStations?latitude=" + lat + "&longitude=" + lng + "&dummy=1";
		Log.i("url", url);
		urlSender(url);
	}
	
	private void statsByName(String name) {	
		if (statsByNameSend == true) {
			return;
		}
		statsByNameSend = true;
		
		try {
			name = URLEncoder.encode(name, "ISO8859-1");	
		} catch (Exception e) {
			Log.e("lookupStations", "Encoding failed", e);//if encoding fails use original and hope for the best
		}
		
		String url = XmlUtil.SERVICE_BASE + "/LocateStations?name=" + name + "&dummy=1";
		Log.i("url", url);
		urlSender(url);
	}
	
	private void statsByIds(String ids) {	
		final String url = XmlUtil.SERVICE_BASE + "/LocateStations?list=" + ids + "&dummy=1";
		Log.i("url", url);
		urlSender(url);
	}
	
	private void urlSender(final String url) {
		Thread t = new Thread(new Runnable() {

			@Override
			public void run() {
				try {
					DownloadUtil.getContentString(url, 15000, "ISO-8859-1");
				} catch (IOException e) {
					Log.e("TrainInfo", "stats failed");
				}				
			}			
		});
		t.start();
	}
	

}