package dk.thoerup.traininfo;

import java.util.List;

import android.content.Context;
import android.location.GpsSatellite;
import android.location.GpsStatus;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;


public class LocationLookup implements LocationListener, GpsStatus.Listener {

	LocationManager locManager;
	Context cntx;
	Handler hndl;

	Location lastKnownLocation = null;
	Location savedLocation = null;
	
	boolean isSearching = false;
	boolean hasGps;

	public LocationLookup(Context c, Handler h) {
		cntx = c;
		hndl = h;
	}
	
	
	public boolean hasLocation() {
		return savedLocation != null;
	}
	
	public Location getLocation()
	{
		return savedLocation;
	}
	
	public Location getLastKnownLocation() {
		return lastKnownLocation;
	}

	public void locateStations() {
		
		isSearching = true;
		
		hasGps = false;
		locManager = (LocationManager) cntx.getSystemService(Context.LOCATION_SERVICE);

		List<String> providers = locManager.getProviders(true);		
		
		if (providers.size() > 0) {
			for(String provider : providers) {
				Log.i("Provider", ""+provider);
				if (provider.equalsIgnoreCase("gps")) {
					locManager.addGpsStatusListener(this);
					hasGps = true;					
				}

				locManager.requestLocationUpdates(provider, 0, 0, this);
				Location tmpLastKnown = locManager.getLastKnownLocation(provider);
				if (tmpLastKnown != null) {
					saveLastKnownLocation(tmpLastKnown);
				}
			}
		} else {
			// message that no suitable provider was found
			//hndl.sendEmptyMessage(StationList.NOPROVIDER);
			hndl.sendEmptyMessage(StationList.LookupStates.NOPROVIDER.ordinal());
			
		}
	}
	@Override
	public void onLocationChanged(Location location) {
		if (isSearching == false)
			return;
		
		Log.i("Location", "Got location fix " + location.getLatitude() + ", " + location.getLongitude() + " accuracy=" + location.getAccuracy() + " provider=" +location.getProvider());
		

		if (savedLocation == null || location.getAccuracy() < savedLocation.getAccuracy())
			savedLocation = new Location(location); //save a copy
		
		if (hasGps) {
			if (!location.getProvider().equals("gps")) {
				return; // at least give the gps a chance
			} else if (location.getAccuracy() > 512) {
				return; //if we have a gps provider lets wait for a more precise fix
			}

		}
		stopSearch();
		hndl.sendEmptyMessage(StationList.LookupStates.GOTLOCATION.ordinal());
	}
	
	private void saveLastKnownLocation(Location loc) {
		if (lastKnownLocation == null) { 
			lastKnownLocation = loc; 
		} else {
			if (loc.getTime() > lastKnownLocation.getTime()) {//if loc is more recent than saved
				lastKnownLocation = loc;
			}
		}
	}
	
	public void stopSearch()
	{
		if (isSearching) {
			isSearching = false;
			locManager.removeGpsStatusListener(this);
			locManager.removeUpdates(this);
		}
	}


	@Override
	public void onProviderDisabled(String provider) {
	}


	@Override
	public void onProviderEnabled(String provider) {
	}


	@Override
	public void onStatusChanged(String provider, int status, Bundle extras) {
		// TODO Auto-generated method stub

	}


	@Override //GpsStatus.Listener
	public void onGpsStatusChanged(int event) {
		if (event == GpsStatus.GPS_EVENT_SATELLITE_STATUS) {
			int count = 0;
			GpsStatus status =  locManager.getGpsStatus(null);
			for (GpsSatellite sat : status.getSatellites()) {
				count ++;
			}
			
			Message msg = new Message();
			msg.what = StationList.LookupStates.GPS_SAT_COUNT.ordinal();
			msg.arg1 = count;
			hndl.sendMessage(msg);
		}
		
	}
}