Salesforce Call management controller

CallManagementController

/*The controller sends the XML response*/
public class CallManagementController {
    /*state is required to know the call flow state*/
    public string state { get; set; }
    public string response { get; set; }
  
   public CallManagementController() {
      state='start';
   }

  /* return KooKoo XML */
  public void kookooResponse() {
  String resp;
      if(state.equals('start'))
      {
    String dialNumber;
    String name;
    //Get the caller id
    String fromPhone = ApexPages.currentPage().getParameters().get('cid');
    if (fromPhone!=null) {
      //get only the last 10 digits as we do not want the country code etc
      fromPhone= fromPhone.length() <= 10 ? fromPhone : fromPhone.substring(fromPhone.length() - 10);
      // search Lead and Contact phone number fields
      List<List<SObject>> results = [FIND :fromPhone IN Phone FIELDS
          RETURNING Contact(FirstName, LastName,Owner.Phone), Lead(FirstName, LastName,Owner.Phone)
          LIMIT 1];
    
      // extract the owner phone if there’s a match
      if (!results[0].isEmpty()) {
        //Found the caller as a contact. So get the owner of the contact and dial him
        Contact r = (Contact)results[0][0];
        name = r.firstName + ' ' + r.lastName;
        if (r.owner!=null && r.owner.phone!=null)
          dialNumber = r.owner.phone;
      } else if (!results[1].isEmpty()) {
        //Found the caller as a Lead. So get the owner of the Lead and dial him
        Lead r = (Lead)results[1][0];
        name = r.firstName + ' ' + r.lastName;
        if (r.owner!=null && r.owner.phone!=null)
          dialNumber = r.owner.phone;
      }
      else {
        /*Did not find the caller in our system. So we will create a new lead. Play some message and hangup.
        We could also dial to a default number or ask him to leave a voice mail etc.
        */

        Lead l = new Lead(FirstName='Lead', LastName=fromPhone, Email='[email protected]', Company='test',Phone=fromPhone);
         try{
         insert l;
       }catch(Exception e){
         System.debug('System exception ' + e);
       }
        response = '<response><playtext>Hello new lead</playtext><hangup/></response>';
        return;
       }
    }
    state='dial';
    //If owner is there for caller, we forward the call. Else, we hangup
    if(dialNumber != null)
    {
        dialNumber = dialNumber.replaceAll('\\D','');
        response='<response><playtext>Hello '+name+'.Please wait while we connect.</playtext><dial>'+dialNumber+'</dial></response>';
    }
    else
    {
        response='<response><playtext>Welcome back. Sorry, you have not yet been assigned an agent. Please try again</playtext><hangup/></response>';
    }
    }
  }
}