package com.macaroon.piztor;

import android.app.AlertDialog;
import android.app.Service;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.location.GpsStatus;
import android.os.Bundle;
import android.os.IBinder;
import android.os.SystemClock;
import android.provider.Settings;
import android.util.Log;

public class GPSTracker extends Service implements LocationListener, GpsStatus.Listener {

	private final Context mContext;

	// flag for GPS status
	boolean isGPSEnabled = false;

	// flag for network status
	boolean isNetworkEnabled = false;

	// flag for GPS status
	boolean canGetLocation = false;

	Location location; // location
	double latitude; // latitude
	double longitude; // longitude

	// The minimum distance to change Updates in meters
	private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters

	// The minimum time between updates in milliseconds
	private static final long MIN_TIME_BW_UPDATES = 1000 * 3; // 10 seconds

	// Declaring a Location Manager
	protected LocationManager locationManager;

	// for GPS satellite status listener
	Location mLastLocation;
	long mLastLocationMillis;
	boolean isGPSFix;


	public GPSTracker(Context context) {
		this.mContext = context;
		isGPSFix = false;
		getLocation();
	}

	public Location getLocation() {
		try {
			Log.d("getLocation", "Start getting location......");

			locationManager = (LocationManager) mContext
				.getSystemService(LOCATION_SERVICE);

			// getting GPS status
			isGPSEnabled = locationManager
				.isProviderEnabled(LocationManager.GPS_PROVIDER);

			// getting network status
			isNetworkEnabled = locationManager
				.isProviderEnabled(LocationManager.NETWORK_PROVIDER);

			if (!isGPSEnabled) {
				// no network provider is enabled
			} else {
				this.canGetLocation = true;
				if (isNetworkEnabled) {
					locationManager.requestLocationUpdates(
							LocationManager.NETWORK_PROVIDER,
							MIN_TIME_BW_UPDATES,
							MIN_DISTANCE_CHANGE_FOR_UPDATES, this);

					Log.d("Network", "Network Updated");

					if (locationManager != null) {
						location = locationManager
							.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
						if (location != null) {
							latitude = location.getLatitude();
							longitude = location.getLongitude();

							Log.d("Network", "Received Network Data");
							System.out.println("***From Network: "+latitude + "  " + longitude);
						}
					}
				}// end of network section
				// if GPS Enabled get lat/long using GPS Services
				if (isGPSEnabled) {
					if (true) {
						locationManager.requestLocationUpdates(
								LocationManager.GPS_PROVIDER,
								MIN_TIME_BW_UPDATES,
								MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
						Log.d("GPS", "GPS Updated");
						if (locationManager != null) {
							location = locationManager
								.getLastKnownLocation(LocationManager.GPS_PROVIDER);
							if (location != null) {
								latitude = location.getLatitude();
								longitude = location.getLongitude();

								Log.d("GPS", "Received GPS Data");
								System.out.println("***From GPS: "+latitude + "  " + longitude);

							}
						}
					}
				}// end of GPS section
			}// end of fetching data
			return location;
		} catch (Exception e) {
			e.printStackTrace();
		}
		return location;
	}

	/**
	 * Stop using GPS listener Calling this function will stop using GPS in your
	 * app
	 * */
	public void stopUsingGPS() {
		if (locationManager != null) {
			locationManager.removeUpdates(GPSTracker.this);
		}
	}

	/**
	 * Function to get latitude
	 * */
	public double getLatitude() {
		if (location != null) {
			latitude = location.getLatitude();
		}
		return latitude;
	}

	/**
	 * Function to get longitude
	 * */
	public double getLongitude() {
		if (location != null) {
			longitude = location.getLongitude();
		}
		return longitude;
	}

	/**
	 * Function to check GPS/wifi enabled
	 * 
	 * @return boolean
	 * */
	public boolean canGetLocation() {
		return this.canGetLocation;
	}

	public boolean isGPSFix() {
		return (this.isGPSFix && location != null);
	}

	/**
	 * Function to show settings alert dialog On pressing Settings button will
	 * lauch Settings Options
	 * */
	public void showSettingsAlert() {
		AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);

		// Setting Dialog Title
		alertDialog.setTitle("GPS is settings");

		// Setting Dialog Message
		alertDialog
			.setMessage("GPS is not enabled. Do you want to go to settings menu?");

		// On pressing Settings button
		alertDialog.setPositiveButton("Settings",
				new DialogInterface.OnClickListener() {
					public void onClick(DialogInterface dialog, int which) {
						Intent intent = new Intent(
							Settings.ACTION_LOCATION_SOURCE_SETTINGS);
						mContext.startActivity(intent);
					}
				});

		// on pressing cancel button
		alertDialog.setNegativeButton("Cancel",
				new DialogInterface.OnClickListener() {
					public void onClick(DialogInterface dialog, int which) {
						dialog.cancel();
					}
				});

		// Showing Alert Message
		alertDialog.show();
	}

	@Override
	public void onLocationChanged(Location location) {
		if (location == null) return;
		mLastLocationMillis = SystemClock.elapsedRealtime();
		mLastLocation = location;
	}

	@Override
	public void onProviderDisabled(String provider) {
	}

	@Override
	public void onProviderEnabled(String provider) {
	}

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

	@Override
	public IBinder onBind(Intent arg0) {
		return null;
	}

	@Override
	public void onGpsStatusChanged(int event) {
		switch (event) {
			case GpsStatus.GPS_EVENT_SATELLITE_STATUS:
				if(mLastLocation != null)
					isGPSFix = (SystemClock.elapsedRealtime() - mLastLocationMillis) < 3000;
				break;

			case GpsStatus.GPS_EVENT_FIRST_FIX:
				isGPSFix = true;
				break;
		}
	}
}