/**

 * Copyright (c) 2009-2010 Symbian Foundation and/or its subsidiary(-ies).

 * All rights reserved.

 * This component and the accompanying materials are made available

 * under the terms of the License "Eclipse Public License v1.0"

 * which accompanies this distribution, and is available

 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

 *

 * Initial Contributors:

 * Contributors:

 */

/**

 * Location.js

 * 

 * Web Runtime Service API emulation 

 * WRT v1.1

 * 

 */

(function(){

	var provider = 'Service.Location',

		Interface = 'ILocation';

	/**

	 * Landmark service

	 */

	var LocationService = function(){

		this.GetLocation 			= __GetLocation;

		this.Trace 					= __Trace;

		this.Calculate				= __Calculate;

		this.CancelNotification		= __CancelNotification;		

	}

	device.implementation.extend(provider, Interface, new LocationService() );

	/******************************************************/	

	/******************************************************/	

	/******************************************************/	

	var	context = device.implementation.context,

		_t = context._t,

		method = '',

		result = false,

		DBase = null;

	var transactionIds = new Array();

	var tTransactionId = -1;

	var isTraceInProgress = false;

	var criteriaTrace;

	var callbackTrace;

	/**

	 * Landmarks: GetLocation

	 * @param {Object} criteria

	 */

	function __GetLocation(criteria, callback, flag){	

		method = "GetLocation";

		//	Async call

		flag = flag || false;

		if (!criteria) {

			criteria = new Object();

		}	

		if(typeof criteria.LocationInformationClass == "undefined")

			criteria.LocationInformationClass = "BasicLocationInformation"; // Default value of LocationInformationClass is "BasicLocationInformation" if not provided

		var result = validateArgument('GetLocation',criteria);

		if(result.ErrorCode != 0)

			return result;

		if (typeof callback == 'function') {

			var retVal = context.callAsync(this, arguments.callee, criteria, callback,true);

			transactionIds.push(retVal.TransactionID);  // all transaction ids are pushed on this variable, because CancelNotification function of SAPI doesn't take TransactioID as input

			return retVal;

		}

		if(flag)

		{

			transactionIds.shift();  // Remove oldest TransactionID(FIFO) (Async call)

		}

		DBase = context.getData(provider);

		var returnValue = DBase[criteria.LocationInformationClass];

		locationNotify(criteria.Updateoptions);

		return context.Result(returnValue);

	}

	/**

	 * Location: Trace

	 * @param {Object} criteria

	 * @param {Function} callback function for async call

	 */

	function __Trace(criteria, callback){

		method = "Trace";

		if (!criteria) {

			criteria = new Object();

		}	

		if(typeof criteria.LocationInformationClass == "undefined")

			criteria.LocationInformationClass = "BasicLocationInformation"; // Default value of LocationInformationClass is "BasicLocationInformation" if not provided

		if (typeof callback != 'function') { // callback should be valid function

			return error(device.implementation.ERR_SERVICE_NOT_SUPPORTED,msg.msgCommandNotFound); 

		}

		var result = validateArgument('Trace',criteria);

		if(result.ErrorCode != 0)

			return result;

		criteriaTrace = criteria;

		callbackTrace = callback;

		isTraceInProgress = true;

		locationNotify(criteria.Updateoptions);

		return traceCall(criteria,callback);

	}

	/**

	 * Location: Calculate

	 * @param {Object} criteria

	 */

	function __Calculate(criteria){

		method = "Calculate";

		if(!criteria || !criteria.MathRequest)

			return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgCalcMissingMathReq);

		if(typeof criteria.MathRequest != "string" || (criteria.MathRequest != "FindDistance" && criteria.MathRequest != "FindBearingTo" && criteria.MathRequest != "MoveCoordinates")) // Error check for wrong MathRequest criteria

			return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgCalcWrongTypeMathReq);

		if(typeof criteria.DistanceParamSource != "object" || (typeof criteria.DistanceParamSource.Latitude != "number" || typeof criteria.DistanceParamSource.Longitude != "number" || typeof criteria.DistanceParamSource.Altitude != "number"))

			return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgCalcMissingArgLocCord);

		if(criteria.MathRequest == "FindDistance" || criteria.MathRequest == "FindBearingTo")

		{

			if(typeof criteria.DistanceParamSource != "object" || (typeof criteria.DistanceParamDestination.Latitude != "number" || typeof criteria.DistanceParamDestination.Longitude != "number" || typeof criteria.DistanceParamDestination.Altitude != "number"))

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgCalcMissingArgLocCord);

			if (criteria.MathRequest == "FindDistance") {

				var dist = LatLon.distHaversine(criteria.DistanceParamDestination.Latitude, criteria.DistanceParamDestination.Longitude, criteria.DistanceParamSource.Latitude, criteria.DistanceParamSource.Longitude)*1000;

				if (typeof criteria.DistanceParamDestination.Altitude == "number" && typeof criteria.DistanceParamSource.Altitude == "number") {

					var delta = criteria.DistanceParamDestination.Altitude - criteria.DistanceParamSource.Altitude

					dist = Math.sqrt(dist * dist + delta * delta);

				}

				return context.Result(dist);

			}

			else if (criteria.MathRequest == "FindBearingTo"){

				var bearing = LatLon.bearing( criteria.DistanceParamSource.Latitude, criteria.DistanceParamSource.Longitude,criteria.DistanceParamDestination.Latitude, criteria.DistanceParamDestination.Longitude);

				return context.Result(bearing);				

			}

		}

		else if(criteria.MathRequest == "MoveCoordinates"){

			if(typeof criteria.MoveByThisDistance == "undefined")

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgCalcMissingArgMoveDist);

			if(typeof criteria.MoveByThisBearing == "undefined")

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgCalcMissingArgMoveBear);

			if(typeof criteria.MoveByThisDistance != "number")

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgCalcWrongTypeMoveDist);

			if(typeof criteria.MoveByThisBearing != "number")

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgCalcWrongTypeMoveBear);

			var latLon = new LatLon(criteria.DistanceParamSource.Latitude, criteria.DistanceParamSource.Longitude);

			var dlatLon = latLon.destPoint(criteria.MoveByThisBearing, criteria.MoveByThisDistance/1000);

			var retVal = new Object();

			retVal.Longitude = dlatLon.lon;

			retVal.Latitude = dlatLon.lat;

			retVal.Altitude = criteria.DistanceParamSource.Altitude;

			return context.Result(retVal);

		}

	}

	/**

	 * Location: CancelNotification

	 * @param {Object} criteria

	 */

	function __CancelNotification(criteria){

		method = "Cancel";

		if(!criteria)

				return error(device.implementation.ERR_MISSING_ARGUMENT,msg.msgCancelMissingType);

		var arr = new Array();

		var i = 0;

		var key

		for(key in criteria);

			arr[i++] = key;

		if(!criteria.CancelRequestType && arr.length)

				return error(device.implementation.ERR_NOT_FOUND,msg.msgCancelMissingType);

		if(criteria.CancelRequestType != "GetLocCancel" && criteria.CancelRequestType != "TraceCancel")

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgCancelWrongType);

		if (criteria.CancelRequestType == "GetLocCancel") {

			for (var i = 0; i < transactionIds.length; i++) {

				clearTimeout(transactionIds[i])

			}

		}

		if (criteria.CancelRequestType == "TraceCancel")

		{

			isTraceInProgress = false;

			tTransactionId = -1;

		}

		return context.ErrorResult(device.implementation.ERR_SUCCESS);

	}

	/*******************************

	 * helper functions

	 *******************************/

	/**

	 * Location: traceCall

	 * @param {} 

	 * This function emulates repetitive trace calls,It calls specified callback function after every UpdateInterval untill 

	 * CancelNotification is called

	 */

	function traceCall(){

		var tid = setTimeout(function(){

		if(!isTraceInProgress)

			return;

		DBase = context.getData(provider);

		var returnValue = DBase[criteriaTrace.LocationInformationClass];

		var result,

			eventCode = {completed:2, error:4, progress:9},

		code = eventCode.completed;

		callbackTrace(tTransactionId,code,context.Result(returnValue,0));

		traceCall();

		}, criteriaTrace.Updateoptions.UpdateInterval/1000);

		if(tTransactionId == -1)

			tTransactionId = tid;

		return context.AsyncResult(tTransactionId);

	}

	/**

	 * Location: validateArgument

	 * @param {string,object} callingMethod and criteria

	 * Validates arguments

	 */

	function validateArgument(fun,criteria)

	{

		method = fun;

		if(typeof criteria.Updateoptions != "undefined")

		{

			if(typeof criteria.Updateoptions != "object") // Checking for error in UpdateOptions criteria

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgGetLocationBadArg);

			if(typeof criteria.Updateoptions.UpdateInterval != "undefined" && typeof criteria.Updateoptions.UpdateInterval != "number")

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgGetLocationWrongType);

			if(typeof criteria.Updateoptions.UpdateTimeOut != "undefined" && typeof criteria.Updateoptions.UpdateTimeOut != "number")	

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgGetLocationWrongType);

			if(typeof criteria.Updateoptions.UpdateMaxAge != "undefined" && typeof criteria.Updateoptions.UpdateMaxAge != "number")	

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgGetLocationWrongType);

			if(typeof criteria.Updateoptions.PartialUpdates != "undefined" && typeof criteria.Updateoptions.PartialUpdates != "boolean")	

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgGetLocationWrongType);

			if((typeof criteria.Updateoptions.UpdateInterval != "undefined" && criteria.Updateoptions.UpdateInterval  < 0) || 

					(typeof criteria.Updateoptions.UpdateTimeOut != "undefined" && criteria.Updateoptions.UpdateTimeOut  < 0) ||

					(typeof criteria.Updateoptions.UpdateMaxAge != "undefined" && criteria.Updateoptions.UpdateMaxAge  < 0))

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgGetLocationNegInt);

			if(typeof criteria.Updateoptions.UpdateTimeOut != "undefined" && typeof criteria.Updateoptions.UpdateInterval != "undefined" && criteria.Updateoptions.UpdateInterval > criteria.Updateoptions.UpdateTimeOut)

			{

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgNone);

			}

			/*if((typeof criteria.Updateoptions.UpdateTimeOut != "undefined" && criteria.Updateoptions.UpdateTimeOut <= 1000000))// || (typeof criteria.Updateoptions.UpdateInterval != "undefined" && criteria.Updateoptions.UpdateInterval <= 1000000))

			{

				return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgNone);

			}*/				

		}

		if(typeof criteria.LocationInformationClass != "undefined" && criteria.LocationInformationClass != "BasicLocationInformation" && criteria.LocationInformationClass != "GenericLocationInfo") // checking for errors in LocationInformationClass criteria

			return error(device.implementation.ERR_BAD_ARGUMENT_TYPE,msg.msgGetLocationWrongCat);

		if (/^Trace$/i.test(fun)&&(!criteria.Updateoptions || typeof criteria.Updateoptions.UpdateInterval == "undefined")) {

			if(!criteria.Updateoptions)

			{

				criteria.Updateoptions = new Object();

			}

			criteria.Updateoptions.UpdateInterval = 1000000;  // Emulation only!! for convenience UpdateInterval is set to 1 second is not specified or if it less than 1 second

			context.notify("Using default UpdateInterval(1000000 micro seconds)"); 

		}

		return context.ErrorResult(device.implementation.ERR_SUCCESS, "");

	}

	/**

	 * Location: error

	 * @param {number,string} ErrorCode and ErrorString

	 * Replaces Error String with method name

	 */

	function error(code, msg /*, args...*/){

		var args = ['location',method].concat([].slice.call(arguments,2));

		msg = msg ? _t().arg.apply(msg,args) : undefined;

		return context.ErrorResult(code, msg);

	}

	function locationNotify(updateoptions) {

		if(!updateoptions)

			return;

		if(typeof updateoptions.UpdateTimeOut != "undefined")

			context.notify(_t("%s:: %s : Updateoptions.UpdateTimeOut not implemented in preview").arg(provider, method));

		if(typeof updateoptions.UpdateMaxAge != "undefined")

			context.notify(_t("%s:: %s : Updateoptions.UpdateMaxAge not implemented in preview").arg(provider, method));

		if(typeof updateoptions.PartialUpdates != "undefined")

			context.notify(_t("%s:: %s : Updateoptions.PartialUpdates not implemented in preview").arg(provider, method));

	}

	/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -  */

	/*  Latitude/longitude spherical geodesy formulae & scripts (c) Chris Veness 2002-2009            */

	/*	http://www.movable-type.co.uk/scripts/latlong.html											  */  

	/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -  */

	/*

	 * Use Haversine formula to Calculate distance (in km) between two points specified by 

	 * latitude/longitude (in numeric degrees)

	 *

	 * example usage from form:

	 *   result.value = LatLon.distHaversine(lat1.value.parseDeg(), long1.value.parseDeg(), 

	 *                                       lat2.value.parseDeg(), long2.value.parseDeg());

	 * where lat1, long1, lat2, long2, and result are form fields

	 */

	LatLon.distHaversine = function(lat1, lon1, lat2, lon2) {

	  var R = 6371; // earth's mean radius in km

	  var dLat = toRad(lat2-lat1);

	  var dLon = toRad(lon2-lon1);

	  lat1 = toRad(lat1), lat2 = toRad(lat2);

	  var a = Math.sin(dLat/2) * Math.sin(dLat/2) +

	          Math.cos(lat1) * Math.cos(lat2) * 

	          Math.sin(dLon/2) * Math.sin(dLon/2);

	  var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));

	  var d = R * c;

	  return d;

	}

	/*

	 * ditto using Law of Cosines

	 */

	LatLon.distCosineLaw = function(lat1, lon1, lat2, lon2) {

	  var R = 6371; // earth's mean radius in km

	  var d = Math.acos(Math.sin(toRad(lat1))*Math.sin(toRad(lat2)) +

	                    Math.cos(toRad(lat1))*Math.cos(toRad(lat2))*Math.cos(toRad(lon2-lon1))) * R;

	  return d;

	}

	/*

	 * calculate (initial) bearing between two points

	 *   see http://williams.best.vwh.net/avform.htm#Crs

	 */

	LatLon.bearing = function(lat1, lon1, lat2, lon2) {

	  lat1 = toRad(lat1); lat2 = toRad(lat2);

	  var dLon = toRad(lon2-lon1);

	  var y = Math.sin(dLon) * Math.cos(lat2);

	  var x = Math.cos(lat1)*Math.sin(lat2) -

	          Math.sin(lat1)*Math.cos(lat2)*Math.cos(dLon);

	  return toBrng(Math.atan2(y, x));

	}

	/*

	 * calculate destination point given start point, initial bearing (deg) and distance (km)

	 *   see http://williams.best.vwh.net/avform.htm#LL

	 */

	LatLon.prototype.destPoint = function(brng, d) {

	  var R = 6371; // earth's mean radius in km

	  var lat1 = toRad(this.lat), lon1 = toRad(this.lon);

	  brng = toRad(brng);

	  var lat2 = Math.asin( Math.sin(lat1)*Math.cos(d/R) + 

	                        Math.cos(lat1)*Math.sin(d/R)*Math.cos(brng) );

	  var lon2 = lon1 + Math.atan2(Math.sin(brng)*Math.sin(d/R)*Math.cos(lat1), 

	                               Math.cos(d/R)-Math.sin(lat1)*Math.sin(lat2));

	  lon2 = (lon2+Math.PI)%(2*Math.PI) - Math.PI;  // normalise to -180...+180

	  if (isNaN(lat2) || isNaN(lon2)) return null;

	  return new LatLon(toDeg(lat2), toDeg(lon2));

	}

	/*

	 * construct a LatLon object: arguments in numeric degrees

	 *

	 * note all LatLong methods expect & return numeric degrees (for lat/long & for bearings)

	 */

	function LatLon(lat, lon) {

	  this.lat = lat;

	  this.lon = lon;

	}

	/*

	 * represent point {lat, lon} in standard representation

	 */

	LatLon.prototype.toString = function() {

	  return this.lat.toLat() + ', ' + this.lon.toLon();

	}

	/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -  */

	// extend String object with method for parsing degrees or lat/long values to numeric degrees

	//

	// this is very flexible on formats, allowing signed decimal degrees, or deg-min-sec suffixed by 

	// compass direction (NSEW). A variety of separators are accepted (eg 3º 37' 09"W) or fixed-width 

	// format without separators (eg 0033709W). Seconds and minutes may be omitted. (Minimal validation 

	// is done).

	function parseDeg (str) {

	  if (!isNaN(str)) return Number(str);                 // signed decimal degrees without NSEW

	  var degLL = str.replace(/^-/,'').replace(/[NSEW]/i,'');  // strip off any sign or compass dir'n

	  var dms = degLL.split(/[^0-9.]+/);                     // split out separate d/m/s

	  for (var i in dms) if (dms[i]=='') dms.splice(i,1);    // remove empty elements (see note below)

	  switch (dms.length) {                                  // convert to decimal degrees...

	    case 3:                                              // interpret 3-part result as d/m/s

	      var deg = dms[0]/1 + dms[1]/60 + dms[2]/3600; break;

	    case 2:                                              // interpret 2-part result as d/m

	      var deg = dms[0]/1 + dms[1]/60; break;

	    case 1:                                              // decimal or non-separated dddmmss

	      if (/[NS]/i.test(str)) degLL = '0' + degLL;       // - normalise N/S to 3-digit degrees

	      var deg = dms[0].slice(0,3)/1 + dms[0].slice(3,5)/60 + dms[0].slice(5)/3600; break;

	    default: return NaN;

	  }

	  if (/^-/.test(str) || /[WS]/i.test(str)) deg = -deg; // take '-', west and south as -ve

	  return deg;

	}

	// note: whitespace at start/end will split() into empty elements (except in IE)

	/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -  */

	// extend Number object with methods for converting degrees/radians

	function toRad (deg) {  // convert degrees to radians

	  return deg * Math.PI / 180;

	}

	function toDeg (rad) {  // convert radians to degrees (signed)

	  return rad * 180 / Math.PI;

	}

	function toBrng (rad) {  // convert radians to degrees (as bearing: 0...360)

	  return (toDeg(rad)+360) % 360;

	}

	/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -  */

	// extend Number object with methods for presenting bearings & lat/longs

	function toDMS (num) {  // convert numeric degrees to deg/min/sec

	  var d = Math.abs(num);  // (unsigned result ready for appending compass dir'n)

	  d += 1/7200;  // add ½ second for rounding

	  var deg = Math.floor(d);

	  var min = Math.floor((d-deg)*60);

	  var sec = Math.floor((d-deg-min/60)*3600);

	  // add leading zeros if required

	  if (deg<100) deg = '0' + deg; if (deg<10) deg = '0' + deg;

	  if (min<10) min = '0' + min;

	  if (sec<10) sec = '0' + sec;

	  return deg + '\u00B0' + min + '\u2032' + sec + '\u2033';

	}

	function toLat (deg) {  // convert numeric degrees to deg/min/sec latitude

	  return toDMS(deg).slice(1) + (deg<0 ? 'S' : 'N');  // knock off initial '0' for lat!

	}

	function toLon (deg) {  // convert numeric degrees to deg/min/sec longitude

	  return toDMS(deg) + (deg>0 ? 'E' : 'W');

	}

	function toPrecision (num,fig) {  // override toPrecision method with one which displays 

	  if (num == 0) return 0;                      // trailing zeros in place of exponential notation

	  var scale = Math.ceil(Math.log(num)*Math.LOG10E);

	  var mult = Math.pow(10, fig-scale);

	  return Math.round(num*mult)/mult;

	}

	/** 

	 * error messages

	 * order of %s args: Service name, method name, parameter name 

	 */

	var msg = {

		msgCommandNotFound			: '%s : Command Not found',

		msgGetLocationWrongCat		: '%s : %s : wrong category info should be BasicLocationInformation/GenericLocationInfo ',

		msgGetLocationBadArg		: '%s : %s : BadArgument - Updateoptions',

		msgGetLocationNegInt		: '%s : %s : Negative Time Interval',

		msgGetLocationWrongType 	: '%s : %s : UpdateOptions Type mismatch',

		msgTraceWrongCat			: '%s : %s : Invalid LocationInformationClass',

		msgCalcMissingMathReq 		: '%s : %s : Missing argument - MathRequest',

		msgCalcWrongTypeMathReq 	: '%s : %s : Wrong argument - MathRequest',

		msgCalcMissingArgLocCord 	: '%s : %s : Missing argument - locationcoordinate',