//Declare global variables  
  var color = null;
  var descriptionLanguage = null;
  var calculationMode = null;
  var routePoints = new Array();
  var type = null;
  var geocoder = null;
  var router = null;
  var routePointsCount = null;
  var geocodedPointsCount = null;
  var routeID = null;
  var viaLocs = new Array();
  var startLoc = null;
  var destLoc = null;
  
  function goMap24() {
  	Map24.loadApi( ["core_api", "wrapper_api"] , map24ApiLoaded );
  }
  
  function map24ApiLoaded(){
    Map24.MapApplication.init( { NodeName: "maparea" } ); 
  }
 
  function startRouting(){
  	
    //Initialize the array for storing route points
    routePoints = {};
    //Initialize the counter for geocoded addresses
    geocodedPointsCount = 0;
    
    //Access the calculation mode from the radio buttons
    if ( $v('fast').checked )
      calculationMode = "Fastest";                                      
    else
      calculationMode = "Shortest";
    
    //Access the type of route to be calculated (either for car or pedestrian)
    type = Map24.trim( $v('type') );
      
    //Access the description language setting
    descriptionLanguage = Map24.trim( $v('descriptionLanguage') );
  
    //Access the chosen measuring unit (only if the description language is english).
    //Internally, the measuring unit is passed in the descriptionLanguage value:
    //"en" for kilometers and "us" for miles.
    if(descriptionLanguage == "en"){
    	descriptionLanguage = document.getElementById("measuringUnit").value;
    }
    
    //Retrieve start and destination of the route from the input fields
    var start = Map24.trim( $v('start') );
    var destination = Map24.trim( $v('destination') );
    
    //Check if the fields for setting the start and destination points are empty
    if( start == "" ) { alert("Please enter start address!"); return; }
    if( destination == "" ) { alert("Please enter destination address!"); return; }
    
    //Retrieve via points from the input fields. 
    //Ignore empty fields and fields that are filled with whitespaces only.
    var vias = [];
    for( var i=0; i < 4; i++ ){
      if( Map24.trim( $v( "via_"+i ) ) != "" )
        vias.push( $v("via_"+i) );
    }
    
    //Create a counter that contains the number of route points
    routePointsCount = 2 + vias.length;
   
    //Disable the button for starting a route calculation.
    document.getElementById("button_calculate_route").disabled = true;
 
    //Create a geocoder stub
    if( geocoder == null ) geocoder = new Map24.GeocoderServiceStub();
    
    //Geocode the start address of the route
    //Define the name of the callback function that is called when the result is available on the client.
    geocoder.geocode({
      SearchText: start,
      CallbackFunction: setRoutePoint,
      CallbackParameters: {position: "start"}
    });
    
    //Geocode the destination address of the route.
    geocoder.geocode({
      SearchText: destination,
      CallbackFunction: setRoutePoint,
      CallbackParameters: {position: "destination"}
    });
    
    //Geocode the via points.
    for( var i=0; i < vias.length; i++ ) {
      geocoder.geocode({
        SearchText: vias[i],
        CallbackFunction: setRoutePoint,
        CallbackParameters: { position: "via", index: i }
      });
    }
    
  }
 
  //Callback function that is called when the geocoding result is available.
  //The locations parameter contains an array with multiple alternative geocoding results.
  //The params parameter passes the value of CallbackParameters that specifies which route 
  //end point is returned (start or destination point).
  function setRoutePoint(locations, params){
  	
    //Check if the geocoded address is a via point.
    if( params.position == "via") {
      //Check if via points were provided in the request at all.
      if( typeof routePoints[ "via" ] == "undefined") 
        routePoints[ "via" ] = [];
      //Store the via point
      routePoints[ params.position ][ params.index ] = locations[0];
    }
    else 
      //Store the geocoded start or destination point
      routePoints[ params.position ] = locations[0];
    
      //Increment the counter for geocoded addresses
      geocodedPointsCount++;
    
    //If all addresses are geocoded successfully, this function calls the calculateRoute() function.
    if( geocodedPointsCount == routePointsCount ) {
      calculateRoute(); 
	  }  
  }
  
  //Calculate the route.
  function calculateRoute() {
    //Set the transit radius for all via points.
    //Create new Map24.Location objects first
    //with the coordinates of the via points.
    for (var i=0; i<(routePointsCount-2); i++){
      var via = new Map24.Location({
        Longitude: routePoints["via"][i].getLongitude(),
        Latitude: routePoints["via"][i].getLatitude()
      })
      //Set the transit radius
      via.setTransitRadius( parseInt(Map24.trim(document.getElementById('radius'+i).value * 1000)) );
      //Store the new locations in the routePoints array
      //The old locations are overwritten
      routePoints["via"][i] = via;  
    }
    document.getElementById("print").disabled = true; 
    
    //Create a routing service stub
    if( router == null ) router = new Map24.RoutingServiceStub();
 
    //Calculate the route. 
    router.calculateRoute({
      Start: routePoints["start"],
      Destination: routePoints["destination"],
      //Specify further routing options
      CalculationMode: calculationMode,
      VehicleType: type,
      ViaPoints: routePoints["via"],
      DescriptionLanguage: descriptionLanguage,
      CallbackFunction: displayRoute,
      //The ShowRoute parameter is set to false, the route is not shown automatically.
      //This is necessary if you want to change the default color used for showing the route.
      //To show the route call the Map24.RoutingServiceStub.showRoute() function in the callback function.
      ShowRoute: false  
    });
  }
  
  
  //Callback function used to access the result of the route calculation.
  //This function is called after the client has received the result from the Routing Service.
  //The route parameter is of type Map24.WebServices.Route.
  function displayRoute( route ){
    //Remember the routeId. It is used e.g. to hide the route.
    routeID = route.RouteID;
    
    //Access the selected color from list box
    color = document.getElementById("colorBox").value;
     
    //Show the route with the selected color and default transparency value.
    //The transparency can be set to a value between 0 (completely transparent) and 255 (opaque). 
    router.showRoute({
      RouteId: routeID,
      Color: [color, 150]
    });
    
    //Add a location at the position of the route's start point.
    startLoc = new Map24.Location({
      Longitude: routePoints["start"].getLongitude(),
      Latitude: routePoints["start"].getLatitude(),
      Description: "Start Point",
      SymbolId: 20950
    }); 
    startLoc.commit();
    
	  //Add a location at the position of the route's destination point.
    destLoc = new Map24.Location({
      Longitude: routePoints["destination"].getLongitude(),
      Latitude: routePoints["destination"].getLatitude(),
      Description: "Destination Point",
      SymbolId: 20958
    });
    destLoc.commit();    
      	
    //Add locations at the position of the route's via points.	
    for(var i = 0; i < (routePointsCount-2); i++){
      var loc = new Map24.Location({
        Longitude: routePoints["via"][i].getLongitude(),
        Latitude: routePoints["via"][i].getLatitude(),
        Description: "Via Point "+(i+1),
        SymbolId: 20951
      });
      loc.commit();   
      viaLocs[i] = loc;   		
    }
        
    //Access the assumed time needed for traversing the route in hours
    var totalTime = ((route.TotalTime)/(60*60) ).toPrecision(3) 
    //Access the total lenght of the route in kilometers
    var totalLength = (route.TotalLength/1000) 
    //Create table with description of the route
    var div_content = "Total Time: " + totalTime + " h<br>" ;     
    div_content += "Total Length: "+ totalLength +" km<br>";
    div_content += "<br>";
 
    //Iterate through the route segments and output the step-by-step textual description of the route
    for(var i = 0; i < route.Segments.length; i++){
      if( typeof route.Segments[i].Coordinates != "undefined" ) {
        coordinates = route.Segments[i].Coordinates;
       
        //Access the longitudes and latitudes of the route segment's coordinates array
        var longitudes = route.Segments[i].Coordinates.Longitudes.toString().split("|");
        var latitudes = route.Segments[i].Coordinates.Latitudes.toString().split("|");
         
        //Get the longitude and latitude in the center of the route segment. 
        //These values are needed for centering on a route segment.
        var centerLon = longitudes[parseInt(longitudes.length / 2)];
        var centerLat = latitudes[parseInt(latitudes.length / 2)];
      }
 
      //For each route segment add the route description and the button for centering on a route segment
      for(var j = 0; j < route.Segments[i].Descriptions.length; j++){
      	//The route description contains tags for further evaluation. For example, the [M24_STREET] tag is used 
      	//to denote a street in the description. Add the following line of code to replace these tags by a blank:
        div_content += (i+1) + ". " + route.Segments[i].Descriptions[j].Text.replace(/(\[|\[\/)[0-9A-Z_]+\]/g, '' ) 
        + "<img src=\"http://devnet.map24.com/demo/ajax/2.0_beta/img/centerabove_std.gif\" alt=\"Center\" onclick=\"centerOnSegment("+centerLon+", "+centerLat+");\"/><br>"
      }
    }
    //Show the route description
    document.getElementById('routeDescription').innerHTML = div_content;
    //Enable the buttons for hiding or removing the route, and for printing the route description
    document.getElementById("button_hide_route").disabled = false;
    document.getElementById("button_remove_route").disabled = false;
    document.getElementById("print").disabled = false;
  }
  
  //Show the route and route points.
  function showRoute (routeID) {
    router.showRoute( {RouteId: routeID, Color: [color, 150]} );
    startLoc.show();
    destLoc.show();
    for(var i = 0; i < (routePointsCount-2); i++){
      viaLocs[i].show();
    } 
    document.getElementById("button_show_route").disabled = true;
    document.getElementById("button_hide_route").disabled = false;
    document.getElementById("button_remove_route").disabled = false;
  }
  
  //Hide the route and route points.
  function hideRoute(routeID) {
    router.hideRoute( {RouteId: routeID} );
    startLoc.hide();
    destLoc.hide();
    for(var i = 0; i < (routePointsCount-2); i++){
      viaLocs[i].hide();
    }  
    document.getElementById("button_remove_route").disabled = true;
    document.getElementById("button_show_route").disabled = false;
    document.getElementById("button_hide_route").disabled = true;
  }
  
  //Removes a route. After the route is removed, a new route can be calculated.
  function removeRoute(routeID) {
    router.removeRoute( {RouteId: routeID} );   
    startLoc.remove();
    destLoc.remove();
    for(var i = 0; i < (routePointsCount-2); i++){
      viaLocs[i].remove();
    } 
    
    document.getElementById("button_show_route").disabled = true;
    document.getElementById("button_hide_route").disabled = true;
    document.getElementById("button_remove_route").disabled = true;
    document.getElementById("routeDescription").innerHTML = "";
    document.getElementById("button_calculate_route").disabled = false;
    document.getElementById("print").disabled = true;   
  }
 
  
  //This function is called after the user has selected a route segment to center on.
  function centerOnSegment (centerLon, centerLat){
    //Center on the given variable
    Map24.MapApplication.center( { Coordinate:new Map24.Coordinate(centerLon, centerLat), MinimumWidth: 3034 } );
  }
  
  //Print Description function. 
  //The function opens a print preview window of the route description and one can choose the printer.
  function printRouteDescription(){
    var printContent = document.getElementById("routeDescription");
    var windowPrint = window.open('','','left=0,top=0,width=0,height=0,toolbar=0,scrollbars=0,status=0');
    windowPrint.document.write(printContent.innerHTML);
    windowPrint.document.close();
    windowPrint.focus();
    windowPrint.print();
    windowPrint.close();
	}
  
  //Helper function for accessing the div specified in the id parameter.
  //The function checks first if the div contains content.
  function $v( id ) { 
    return   (document.getElementById( id ).value != "undefined") ?  
      document.getElementById( id ).value : ""; 
  }