/**
 * Android App that utilizes the GPS functionality in an Android Phone
 **/

package com.GPS.GPSLocator;

//Classes in order to show map view & related functionalities
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapView;
import com.google.android.maps.MapController;
import com.google.android.maps.GeoPoint;
import android.content.Context;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;

import android.location.Geocoder;
import android.location.Address;

//Classes related to display location icon on the screen
import com.google.android.maps.Overlay;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Point;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;

import java.util.List;
import java.util.Locale;
import java.io.IOException;

import org.apache.http.client.CircularRedirectException;

import android.os.Bundle;
import android.widget.Toast;

/**
 * Class GPSLocatorActivity
 * 
 * Description: This class extends MapActivity. It sets the basic view and
 * navigations to Google Maps view. It also gets an instance of location manager
 * and sets location listener for callback functions.
 * 
 * @author Madhavi
 * @author Viral
 */

public class GPSLocatorActivity extends MapActivity {
	// Actual view being shown on screen
	private MapView mapView;
	// Controller for MVC
	private MapController mapController;

	// Location manager related objects
	private LocationManager locationManager;
	private LocationListener locationListener;

	// Location update variables
	private long LocUpdateTimeouts = 0; //5000; // in mili-seconds
	private Float LocUpdateDistance = (float) 0; //10; // meters

	/*
	 * function onCreate() This is a callback function. It is called by Android
	 * OS framework. This call is very important to start the android activity.
	 * 
	 * @see com.google.android.maps.MapActivity#onCreate(android.os.Bundle)
	 * 
	 * @see com.GPS.GPSLocator.GPSLocationListener
	 */
	
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);

		// Get a location manager.
		String context = Context.LOCATION_SERVICE;
		locationManager = (LocationManager) getSystemService(context);

		// create a context
		Criteria criteria = new Criteria();
		criteria.setAccuracy(Criteria.ACCURACY_FINE);
		criteria.setAltitudeRequired(false);
		criteria.setBearingRequired(false);
		criteria.setCostAllowed(true);
		criteria.setPowerRequirement(Criteria.POWER_LOW);
		String provider = locationManager.getBestProvider(criteria, true);

		// get current location
		Location location = locationManager.getLastKnownLocation(provider);

		// Set location listener & callback
		// GPSLocationListener is a custom class.
		locationListener = new GPSLocationListener();

		locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0,
				0, locationListener);

		mapView = (MapView) findViewById(R.id.mapView);

		// enable Street view by default
		mapView.setStreetView(true);

		mapView.setBuiltInZoomControls(true);

		// set default zoom level
		mapController = mapView.getController();
		mapController.setZoom(16);
	}

	/**
	 * function: isRouteDisplayed() We are not showing routes hence this will
	 * always return false.
	 */
	
	@Override
	protected boolean isRouteDisplayed() {
		return false;
	}

	/**
	 * Class GPSLocationListener
	 * 
	 * This class implements LocationListener. It mainly handles the location
	 * updates.
	 * 
	 * @author Viral
	 * @author Madhavi
	 */
	
	private class GPSLocationListener implements LocationListener {
		/*
		 * function: onLocationChanged(Location) This function updates the
		 * current position on the map. This happens whenever location update is
		 * received.
		 */

		@Override
		public void onLocationChanged(Location location) {
			if (location != null) {
				// create GeoPoint object from location update
				GeoPoint point = new GeoPoint(
						(int) (location.getLatitude() * 1E6),
						(int) (location.getLongitude() * 1E6));

				// update map to show required area
				mapController.animateTo(point);
				// update zoom level
				mapController.setZoom(16);

				// add marker
				// show current location
				// 1. create a map overlay
				MapOverlay mapOverlay = new MapOverlay();
				// 2. show current GeoPoint location
				mapOverlay.setPointToDraw(point);
				List<Overlay> listOfOverlays = mapView.getOverlays();
				listOfOverlays.clear();
				// 3. update overlay
				listOfOverlays.add(mapOverlay);

//				String address = ConvertPointToLocation(point);
//				Toast.makeText(getBaseContext(), address, Toast.LENGTH_SHORT)
//						.show();
				// force redraw
				mapView.invalidate();
			}
		}

		// we do not utilize these functions for now
		// implemented as interface requirements

		@Override
		public void onProviderDisabled(String provider) {
		}

		@Override
		public void onProviderEnabled(String provider) {
		}

		@Override
		public void onStatusChanged(String provider, int status, Bundle extras) {
		}
	}

	/**
	 * Class MapOverlay
	 * 
	 * It extends Overlay class to draw current location on the map view.
	 * 
	 * @author Madhavi
	 * @author Viral
	 */
	
	class MapOverlay extends Overlay {
		// point to be drawn
		private GeoPoint pointToDraw;

		// setter method for the point to be drawn
		public void setPointToDraw(GeoPoint point) {
			pointToDraw = point;
		}

		// getter method for the point to be drawn
		public GeoPoint getPointToDraw() {
			return pointToDraw;
		}

		/**
		 * function: draw(Canva, Mapview, boolean, long)
		 * 
		 * This function draws given bitmap on to the map view.
		 * 
		 */
		
		@Override
		public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
				long when) {
			super.draw(canvas, mapView, shadow);
			// convert point to pixels
			Point screenPts = new Point();
			mapView.getProjection().toPixels(pointToDraw, screenPts);

			// add marker
			//Bitmap bmp = BitmapFactory.decodeResource(getResources(), red);
			Bitmap bmp = BitmapFactory.decodeResource(getResources(),R.drawable.icon);
			Paint oPaint = new Paint();
			oPaint.setAntiAlias(true);
			
			//canvas.drawBitmap(bmp, screenPts.x, screenPts.y - 24, null); 
			// 24 is the height of image
			canvas.drawBitmap(bmp, screenPts.x, screenPts.y - 24, oPaint);
			return true;
		}
	}
}