Add participant ID

Collect participant ID at the beginning, store in database, export with
results.  Closes https://github.com/mattbk/changeblindness/issues/2.

index.php

@@ -69,6 +69,10 @@ switch ($mode) {
         $variables['imageWithElement'] = 'img/'.$phase.'-with.png';
         $variables['imageWithoutElement'] = 'img/'.$phase.'-without.png';
         $variables['step_count'] = $index;
+		// Store the participant ID with some simple validation to prevent SQL injection
+		if (isset($_POST['participantid'])) {
+			$_SESSION['participantid'] = preg_replace('/[^A-Za-z0-9\. -]/', '', $_POST['participantid']);
+			}          
         break;
     case 'phase_next':
         $template = 'next.html.twig';
@@ -107,12 +111,16 @@ switch ($mode) {
 		//Building an INSERT query:
 		//Include userid (once collection form is added into the start page)				
 		// DB fields are listed here:
-		$columnstoimplode = array("uid", "datetime", "host", "phase", "xcoordinate", "ycoordinate","responsetime","score");
+		$columnstoimplode = array("uid", "datetime", "host", "participantid","phase", "xcoordinate", "ycoordinate","responsetime","score");
 		// Note that backticks (`) go around field names...
 		$columns = "`".implode("`, `", $columnstoimplode)."`";
 		// Set up timestamp so you can tell participants apart.  http://alvinalexander.com/php/php-date-formatted-sql-timestamp-insert
 		$timestamp = date('Y-m-d G:i:s');
+		// Add the uid placeholder, timestamd, and host/IP
 		$valuestoimplode = array("", $timestamp, $_SERVER['REMOTE_ADDR']);
+		// Add the participant ID
+		array_push($valuestoimplode,$_SESSION['participantid']);
+		// Add the results
 		$valuestoimplode = array_merge($valuestoimplode,$ready);
 		$values  = "'".implode("', '", $valuestoimplode)."'";
 		//print_r($values);
@@ -170,7 +178,7 @@ switch ($mode) {
             $stats = array();
 
 			//Skip empty results (created during debugging)            
-			if ($record['responsetime'] > 0) {
+			if ($record['participantid'] != "") {
 				//Put your results in one array
 				$variables['data'][] = $record;  
 				}
@@ -188,7 +196,6 @@ switch ($mode) {
 
 } //End while to loop through results from database.
 
-
 	$results->free();
 	break;    
 } //End case to select page.

views/index.html.twig

@@ -4,7 +4,12 @@
     <header class="hero-unit">
         <h1>Change blindness test</h1>
         <p>We would like a few minutes of your time to help us with a test in change blindness. Your help is very much appreciated.</p>
-        <p><a class="btn btn-primary btn-large" href="{{ start_url }}">Get started &raquo;</a></p>
+
+		<form action="{{ start_url }}" method="post">
+		Name: <input type="text" name="participantid">
+		<input type="submit" value="Start">
+		</form>
+
         <p><div class="fb-like" data-layout="button_count" data-width="450" data-show-faces="false" data-font="arial"></div></p>
         <p><a href="https://twitter.com/share" class="twitter-share-button" data-via="RaymondJelierse" data-hashtags="vcd">Tweet</a></p>
     </header>

views/results.html.twig

@@ -54,6 +54,7 @@
                 <th>uid</th>
                 <th>date</th>
                 <th>host</th>
+                <th>participant</th>
                 <th>phase</th>
                 <th>x</th>
                 <th>y</th>
@@ -67,6 +68,7 @@
                 <td>{{record.uid}}.</td>
                 <td>{{ record.datetime }}</td>
                 <td>{{ record.host }}</td>
+                <td>{{ record.participantid }}</td>                
                 <td>{{ record.phase }}</td>
                 <td>{{ record.xcoordinate }}</td>
                 <td>{{ record.ycoordinate }}</td>

views/results.txt.twig

@@ -1,4 +1,4 @@
-uid	datetime	host	phase	xcoordinate	ycoordinate	responsetime	score
+uid	datetime	host	participant	phase	xcoordinate	ycoordinate	responsetime	score
 {% for record in data %}
-{{record.uid}}	{{record.datetime}}	{{record.host}}	{{record.phase}}	{{record.xcoordinate}}	{{record.ycoordinate}}	{{record.responsetime}}	{{record.score}}
+{{record.uid}}	{{record.datetime}}	{{record.host}}	{{record.participantid}}	{{record.phase}}	{{record.xcoordinate}}	{{record.ycoordinate}}	{{record.responsetime}}	{{record.score}}
 {% endfor %}