<?php 
/*********************************************************************************************************
  "Ensemble" is the proprietary property of The Regents of the University of California ("The Regents.")

  Copyright (c) 2005-10 The Regents of the University of California, Davis campus. All Rights Reserved.

  Redistribution and use in source and binary forms, with or without modification, are permitted by
  nonprofit, research institutions for research use only, provided the conditions in the included
  license agreement are met.

  Refer to the file "ensemble_license.txt" for the license agreement,
  located in the top level directory of this distribution.

**********************************************************************************************************/
//Author: Stefan Tomic
//Janata Lab
//Center for Mind and Brain
//Developed for the Ensemble Project


//This file contains the routines to query for the next form in the questionnaire associated with a user session, and to
//update the session table
//
// updates the form_id session variable and calls the next static or dynamic form
//
// S.T. 9/14/04 original version 
// S.T. 1/23/05 revisions for generating forms on the fly
// S.T. Apr/May 2005 revisions for looping and handling trials
  // P.J. 25May2014 added setting of misc_info session variable to empty in order to avoid propagation across trials

require_once('../include/subject_includes.php');

function clear_loop_vars() {
	$_SESSION['looping'] = FALSE;
	$_SESSION['loop_incr_trial'] = FALSE; 
	unset($_SESSION['loop_end']);
	unset($_SESSION['loop_iter']);
	unset($_SESSION['loop_repeat']);
	unset($_SESSION['loop_goto']);

}

if($_SESSION['check_consent'])
	include('check_consent.php');
$_SESSION['check_consent'] = FALSE;
$_SESSION['stimulus_completed'] = FALSE;

$_SESSION['misc_info'] = "";

if($_SESSION['last_visited'] == "") {
	$_SESSION['last_visited'] = 1; //last visited was blank, so this is the first dynamic form
}
else {

	//increment response_order, regardless of whether or not we are looping

	//if we are not currently in a loop, see if this form has a loop in place
	//if it does, initiate a new loop

	if(!$_SESSION['looping']) {
		
		$query_looping = sprintf("SELECT * from experiment_x_form where experiment_id=%d and form_order=%d ",$_SESSION['experiment_id'],$_SESSION['last_visited']);
		mysql_select_db($database_subject,$subject);
		$looping = mysql_query($query_looping,$subject) or report_error_form(mysql_error());
		$row_looping = mysql_fetch_assoc($looping);
		//if 'goto' and 'repeat' fields are set for this form, then a loop needs to be initiated. 
		//The 'num_skip_forms' session variable is checked to see if we are skipping this loop on first iteration (goto and repeat weren't set yet)
		if($row_looping['goto'] != "" and $row_looping['goto'] > 0 and $row_looping['repeat'] != "" and $row_looping['repeat'] > 0 and ($_SESSION['num_skip_forms'] == 0)) {
			$_SESSION['looping'] = true; //boolean for whether we are currently in a loop or not
			$_SESSION['loop_end'] = $row_looping['form_order']; //set current location as loop end
			$_SESSION['loop_iter'] = 1; //keeps track of the number of loop iterations progressed
			$_SESSION['loop_repeat'] = $row_looping['repeat']; //keep track of total # of repeats
			$_SESSION['loop_goto'] = $row_looping['goto']; //loop_goto keeps track of beginning of loop
			
			//if looping back to the same form handler, just increment the trial number
			//if looping back to a different form handler, set 'last_visited' and reset trial number
			
			if($_SESSION['loop_goto'] != $_SESSION['last_visited']) {
				$_SESSION['last_visited'] = $row_looping['goto'];
			}
		}
		//if after checking for a loop, there is none, then just go to the next form
		else {
				//if skipping forms, increment by that number instead and then zero out
				//the num_skip_forms variable.
				if($_SESSION['num_skip_forms'] != 0) {
					$_SESSION['last_visited'] += $_SESSION['num_skip_forms'];
					$_SESSION['num_skip_forms'] = 0;
				}
				else
					$_SESSION['last_visited']++;
		}
		
	
	}
	//otherwise, if we are currently in a loop, do the following
	else {
		$skipping_forms = (isset($_SESSION['num_skip_forms']) && ($_SESSION['num_skip_forms'] != 0));
		if($skipping_forms) {
				$_SESSION['last_visited'] += $_SESSION['num_skip_forms'];
				$_SESSION['num_skip_forms'] = 0;
				if($_SESSION['last_visited'] > $_SESSION['loop_end']) 
					clear_loop_vars();

		}
		//if we have reached the end of the loop, do some checking
		elseif($_SESSION['last_visited'] >= $_SESSION['loop_end']) {
		
			//we have reached the end of the loop again, so increase the loop iteration counter
			$_SESSION['loop_iter']++;
			//if at the end of the loop we have reached the last iteration, clear all loop info out and go to next form
			if($_SESSION['loop_iter'] == $_SESSION['loop_repeat']) {
				clear_loop_vars();
				$_SESSION['last_visited']++;
			}
			else { //otherwise, if we haven't reached the last iteration, go back to the beginning of the loop

				//if looping back to the same form, just increment the trial number
				//if looping back to a different form, set 'last_visited' and reset trial number
				
				if($_SESSION['loop_goto'] != $_SESSION['last_visited']) {
					$_SESSION['last_visited'] = $_SESSION['loop_goto'];
				}
			}
		}
		else { //if we are not at the end of the loop just go to the next form
			$_SESSION['last_visited']++;
		}
	}
	
	
}
$query_next_form = sprintf("SELECT * from experiment_x_form LEFT JOIN form on (form.form_id = experiment_x_form.form_id) WHERE experiment_id = %s AND form_order = %d",
							$_SESSION['experiment_id'],$_SESSION['last_visited']);

mysql_select_db($database_subject,$subject);
$next_form = mysql_query($query_next_form, $subject) or report_error_form(mysql_error());
$row_next_form = mysql_fetch_assoc($next_form);

$next_filename = $questionnaire_location."form_processing/".$row_next_form['form_handler'];

header("Location: $next_filename");

exit;


?>