geolocation.js

/**
 * Location Wrapper
 *
 * @class location
 * @uses core
 */

var App = require('core'),
	lastKnownLocation,
	showError = false,
	callback = false,
	callbackFired = false;

/**
 * Update Device Location
 *
 * This method does not show error
 * if it failed to get location
 */
exports.refreshDeviceLocation = function() {
	console.log("i am updating the device location");
	callback = false;
	callbackFired = false;

	obtainLocation({
		showError: false
	});
};

/**
 * Get Device Location
 *
 * Shows error if failed to get location
 *
 * @param {Object} params An object containing a showError flag and callback function
 * @param {Function} parans.callback A function to execute with device's location
 * @param {Boolean} params.showError Should an error be shown if couldn't find location, true by default
 */
exports.getDeviceLocation = function(params) {

	if (params['callback'] === undefined) {
		params.callback = function() {};
	}

	if (params['showError'] === undefined) {
		params.showError = true;
	}

	callback = params.callback;
	callbackFired = false;

	return obtainLocation({
		showError: params.showError
	});
};

/**
 * Obtain Location
 *
 * The method tries the cached location first.
 * If the cached location is more than 3 minutes old,
 * we force a location update
 *
 * @params {Object} params An object with two possible values:
 * @params {Function} params.callback Function to call when location is obtained
 * @params {Boolean} params.showError Shows an error if showError is true
 */
function obtainLocation(params) {
    console.log("  I am obtaning the location " + JSON.stringfy(params));
	if (params.showError !== undefined) {
		showError = params.showError;
	} else {
		showError = true;
	}

	// Try using cached location/low battery option first
	Ti.Geolocation.getCurrentPosition(function(e) {

		Ti.API.info('obtainLocation.getCurrentPosition: ' + JSON.stringify(e));
		console.log("Cordinated obtained success--> " + e.success);

		if (e.success) {
			console.log("Cordinated obtained success inside loop --> ");

			// Check age of coords
			var coords_time = ((new Date() - e.coords.timestamp) / 1000).toFixed(2);
			logTime(coords_time);

			// If cached location is more than 1 minute old
			// we force a location update
			if (coords_time > 60) {

				Ti.API.warn('Coords Stale. Forcing location Update!');
				updateDeviceLocation();

			} else {

				callbackFired = true;

				if (callback) {
					callback(e);
				}
			}

		} else {

			if (showError) {
				console.log("----i am in show error and it is TRUE-----" + JSON.stringfy(showError));
				displayError(e.code);
			}
		}
	});
}

/**
 * Get device location using more accurate methods
 *
 * For iOS: We setup best accuracy and add listener
 *
 * For Android: We setup two providers (GPS & Network) and
 * each provider has it's own listener function. This is
 * important because using the same listener method for
 * both providers would overwrite the first one.
 */
function updateDeviceLocation() {
	console.log("i am updating the device location");
	if (OS_IOS) {
		Ti.Geolocation.accuracy = Ti.Geolocation.ACCURACY_BEST;
		Ti.Geolocation.distanceFilter = 10;
		Ti.Geolocation.addEventListener('location', locationUpdate);
	}

	if (OS_ANDROID) {
		console.log("i am updating the device location on Android");
		var gpsRule = Ti.Geolocation.Android.createLocationRule({
			provider: Ti.Geolocation.PROVIDER_GPS,
			accuracy: 20,
			//maxAge: 10000,
			minAge: 10000,
		});
		// Setup GPS
		var providerGps = Ti.Geolocation.Android.createLocationProvider({
			name: Titanium.Geolocation.Android.PROVIDER_NETWORK,
			minUpdateDistance: 0.0,
			minUpdateTime: 0
		});

		Ti.Geolocation.Android.addLocationRule(gpsRule);

		Ti.Geolocation.Android.addLocationProvider(providerGps);
		Ti.Geolocation.Android.manualMode = true;
		Titanium.Geolocation.addEventListener('location', gpsUpdate);
		Titanium.Geolocation.addEventListener('location', networkUpdate);


	};

	// Stop monitoring after 10 seconds
	setTimeout(function() {

		removeLocationListener();
	}, 50000);
}

/**
 * Listens for location udpates
 *
 * We only remove the listeners if we have a location
 * that was updated less than 10 seconds ago and is
 * accurate up to 75 meters
 *
 * @param {Object} e
 */
function locationUpdate(e) {

	if (typeof e.coords !== 'undefined' && e.coords.accuracy < 75 && (new Date() - e.coords.timestamp < 10000)) {

		Ti.API.info('locationUpdate.success: ' + JSON.stringify(e.coords));

		if (callback && !callbackFired) {
			callback(e);
		}
		callbackFired = true;

		removeLocationListener();
	}
}

/**
 * Android specific function to handle
 * location updates via GPS
 *
 * @param {Object} e
 */
function gpsUpdate(e) {
	Ti.API.info('gpsUpdate.e: ' + JSON.stringify(e));
	locationUpdate(e);
}

/**
 * Android specific function to handle
 * location updates via Network
 *
 * @param {Object} e
 */
function networkUpdate(e) {
	Ti.API.info('networkUpdate.e: ' + JSON.stringify(e));
	locationUpdate(e);
}

/**
 * This method is used to remove any location
 * listeners setup and may be fired multiple times
 */
function removeLocationListener() {
	console.log("Removing the event listener");
	if (OS_IOS) {
		Ti.Geolocation.removeEventListener('location', locationUpdate);
	}

	if (OS_ANDROID) {
		console.log("Removing the event listener on android");
		Ti.Geolocation.Android.removeEventListener('location', gpsUpdate);
		Ti.Geolocation.Android.removeEventListener('location', networkUpdate);
	}

	if (!callbackFired && showError) {
		callbackFired = true;
		displayError(6);
	}
}

/**
 * Handle network errors
 *
 * @param {Object} code Error code returned by e.code
 */
function displayError(code) {
	var msg = 'Error trying to get location';

	switch (code) {
		case Ti.Geolocation.ERROR_LOCATION_UNKNOWN:
			msg = 'Location unknown';
			break;

		case Ti.Geolocation.ERROR_DENIED:
			msg = 'Access denied';
			break;

		case Ti.Geolocation.ERROR_NETWORK:
			msg = 'Network error';
			break;

		case Ti.Geolocation.ERROR_HEADING_FAILURE:
			msg = 'Failure to detect heading';
			break;

		case Ti.Geolocation.ERROR_REGION_MONITORING_DENIED:
			msg = 'Region monitoring access denied';
			break;

		case Ti.Geolocation.ERROR_REGION_MONITORING_FAILURE:
			msg = 'Region monitoring access failure';
			break;

		case Ti.Geolocation.ERROR_REGION_MONITORING_DELAYED:
			msg = 'Region monitoring setup delayed';
			break;
	}

	App.alert({
		title: 'Location Error',
		message: msg
	});
}

function logTime(coords_time) {
	var str;

	if (coords_time >= 60) {
		str = (coords_time / 60).toFixed(2) + 'mins';
	} else {
		str = coords_time + 'seconds';
	}
	Ti.API.info('Coords Updated: ' + str);
}