<?php
/**
 * This script provides line mixing for educational use
 *
 * This script is free to use for everyone.
 *
 * @copyright  Copyright (c) 2012 Georg Eckenberg
 * @license    free
 * @version    2.0
 * @link       http://www.edu.eckenberg.info/mixer
 */
 
 /* *
  * history
  * 2015-09-05 09:18  start working on old version 2.0 
  * 2015-09-05     :      parse special input string starting with 'Gruppe'
  */
 
    // Visible labels
    $title = 'Gruppen-Mixer';
    $submitstate0 = 'Mixen!';
    $submitstate1 = 'Nochmal!';
    $submitstate2 = 'Puzzlen!';
    $submitstate3 = 'Weiter...';
    $submitpuzzler = 'Gruppenpuzzle!';
    $partslabel = 'Gruppen:'; 
    $puzzlepartslabel = 'Neue Gruppen:'; 
    $grouptitle = 'Gruppe ';
    $sortlabel = 'Ergebnis sortieren';
    $preselection = 'Ausw&auml;hlen!';
    $allmembers  = 'Alle';
    $circlepartslabel = 'Neue Gruppen:';
    $downloadme = 'Dieses Script herunterladen';
    $deletedata = 'Daten l&ouml;schen';
    $drawone = 'Je ein Mitglied ziehen';
    $partsup = "&lt;";
    $partsdown = "&gt;";
    $linesdefault = 'Bitte
hier
die
Mitglieder
der
Gruppe
einf&uuml;gen!'; 

    // Default subgroup size
    $partsaim = 4;
    
    // Clear-Cookie-Reminder
    $cleared = false;
 
    // Return this script for download when clicked on link
    if (@$_GET['download']) {
        header('Content-type: text/plain');
        header('Content-Disposition: attachment; filename="linemixer.php"');   
        readfile(__FILE__);
        exit;
    }

    // Some functions for the linemixer...  
    function linemixer( $lines, $parts, $sortresult = true ) 
    {
        if ($lines) 
        {
            $return = array();
            $linearray = explode("\n", $lines);
            shuffle ( $linearray );
            $linecount = count( $linearray );
            if ($linecount <= $parts) 
            {
                for ($counter = 0; $counter < $linecount; $counter++)
                {
                    $return[] = array( $linearray[$counter] );
                }
            }
            else
            {
                $adders = $linecount % $parts;
                $basegroup = ($linecount - $adders) / $parts;
                $grouplimit = $basegroup;
                $groupcounter = 0;
                $membercounter = 0;
                if ($adders > 0) 
                {
                    $grouplimit++;
                    $adders--;
                }
                for ($counter = 0; $counter < $linecount; $counter++)
                {
                    if ( $membercounter == 0 ) 
                    {
                        $return[$groupcounter] = array();
                    }
                    $return[$groupcounter][$membercounter] 
                        = $linearray[$counter]; 
                    $membercounter++;
                    if ( $membercounter == $grouplimit )
                    {
                        if ( $sortresult ) 
                        {
                            sort ( $return[$groupcounter] );
                        }
                        $groupcounter++;
                        $membercounter = 0;
                        $grouplimit = $basegroup;
                        if ($adders > 0) 
                        {
                            $grouplimit++;
                            $adders--;
                        }
                    }
                }
            }
            return $return; 
        }
        else
        {
            return array();
        }
    }

    function groups2string ( $groups, 
        $groupseparator = "\n", $memberseparator = "\t" )
    {
        $return = '';
        if ( count( $groups ) > 0 )
            {
            foreach ( $groups as $group )
            {
                if ( count($group) > 0 ) 
                {
                    foreach ( $group as $member ) 
                    {
                        $return .= $member . $memberseparator;
                    }
                    $return = substr( $return, 0, -1 );
                }
                $return .= $groupseparator;
            }
            $return = substr( $return, 0, -1 );
        }
        return $return;
    }

    function string2groups ( $string, 
        $groupseparator = "\n", $memberseparator = "\t" ) 
    {
        $return = array();
        $groups = explode ( $groupseparator, $string );
        foreach ( $groups as $groupstring )
        {
            $return[] = explode ( $memberseparator, $groupstring );
        }
        return $return;
    }

    function puzzleunique ( $groups ) 
    {
        $subgroupsize = 0;
        $unique = true;
        foreach ( $groups as $group ) {
            if ( $subgroupsize ) 
            {
                if ( count ( $group ) != $subgroupsize )
                {
                    $unique = false;
                }
            } 
            else
            {
                $subgroupsize = count( $group );
            }
        }
        return $unique;
    }

    function number( $number, $mode ) 
    {
        switch ( $mode )
        {
            case 1:
                return ( chr ( $number + 65 ) );
            break;
            default: 
                return ($number + 1);
        }
    }

    function echogroups ( $grouptitle, $groups, $mode = 0, $drawone=false, 
        $divclass='group', $ulclass='group', $tabs = 1 )
    {
        $counter = 0;
        foreach ( $groups as $group )
        {
            echo ( str_repeat ( "\t", $tabs ) 
                . '<div class="' . $divclass . '">' . "\n");
            $tabs++;
            echo(str_repeat ( "\t", $tabs ) 
                . '<h2>' . $grouptitle . number($counter, $mode) . '</h2>' . "\n");
            echo(str_repeat ( "\t", $tabs ) 
                . '<ul class="' . $ulclass . '">' . "\n");
            $tabs++;
            $membercounter = 0;
            $theone = 0;
            if ( $drawone !== false )
            {
                if ( is_array($drawone) )
                {
                    $theone = $drawone[ $counter ];
                }
                else
                {
                    $theone = rand(1, count($group));
                }
            }
            foreach ( $group as $member ) 
            {
                $membercounter++;
                echo(str_repeat ( "\t", $tabs ) ); 
                if ($theone == $membercounter) 
                {
                    echo( '<span class="theOne">' );
                }
                echo( '<li>' );
                echo( trim ( $member ) );
                echo( '</li>' );
                if ($theone == $membercounter) 
                {
                    echo( '</span>' );
                }                
                echo( "\n" );
            }
            $tabs--;
            echo(str_repeat ( "\t", $tabs ) . '</ul>' . "\n");
            $tabs--;
            echo (str_repeat ( "\t", $tabs ) . '</div>' . "\n");
            $counter++;
        }
    }

    function grouppuzzler ( $groups, $sizeaim, $signmode = 1, $sm2arr = 0 ) 
    {
        $groupcounter = 0;
        $membercounter = 0;
        $orgin = 0;
        $return = array();
        foreach ( $groups as $group ) 
        {
            foreach ( $group as $member ) 
            {
                if ( ! ($membercounter % $sizeaim) ) 
                {
                    $groupcounter=0;
                }
                switch ( $signmode )
                {
                    case 1: 
                        $return [$groupcounter][] = '[' . ($orgin+1) . '] ' . $member;
                    break;
                    case 2:
                        if ( in_array($member, $sm2arr) )
                        {
                            $return [$groupcounter][] 
                                = '<span style="font-weight: bold">' . $member . '</span>';
                        }
                        else
                        {
                            $return [$groupcounter][] = $member;
                        }
                    break;
                    default: 
                        $return [$groupcounter][] = $member;
                }
                $groupcounter++;
                $membercounter++;
            }
            $orgin++;
        }
        return $return;
    }
    
    function isgivendata( $lines, $title, $grouptitle )
    {
        // if lines start with title or group title, 
        // then it appears to be given data
        return
                ( substr($lines, 0, strlen($title)) == $title ) ||
                ( substr($lines, 0, strlen($grouptitle)) == $grouptitle );
    }
    
    function extractgivendatagroups( $lines, $title, $grouptitle, $downloadme )
    {
        $group = array();
        
        // remove title, if lines start with it
        if ( substr($lines, 0, strlen($title)) == $title )
        {
            $lines = substr( $lines, strlen($title), strlen($lines) - strlen($title) );
            $lines = trim( $lines );
        }
        // remove $downloadme, ist lines end with it
        if (    
                substr(
                    $lines, 
                    strlen($lines) - strlen($downloadme), 
                    strlen($downloadme)
                ) == $downloadme 
            ) 
            {
            $lines = substr( $lines, 0, strlen($lines) - strlen($downloadme) );
            $lines = trim( $lines );
        }
        
        // now split the array along the group title
        $parts = explode($grouptitle, $lines);
        $counter = 1;
        foreach ($parts as $part)
        {
            if ( $part )
            {
                if ( substr($part, 0, strlen($counter)) == $counter )
                {
                    $part = substr($part, strlen($counter), 
                        strlen($part)-strlen($counter));
                }
                $counter++;
                $part = trim ($part);
                $members = explode("\n", $part);
                $group[] = $members;
            }
        }
        return $group;
    }
    // Setting default values and deal with superglobals...

    $state = 0;
    if (@$_POST['state']) 
    {
        $state = $_POST['state'];
    }

    $sizeaim = 0;
    $lines = '';
    if (@$_POST['lines']) 
    {
        $lines = $_POST['lines'];
        $lines = htmlentities($lines);
        if ($state == 1 || $state == 4) 
        {
            setcookie('gruppenmixer', base64_encode(trim($lines)), 
                time() + 365*24*3600);
        }
        if (@$_POST['clearcookie']) {
            setcookie('gruppenmixer', "", time() - 1);
            $cleared = true;
        }
    }
    else
    {
        if (@$_POST['clearcookie']) {
            setcookie('gruppenmixer', "", time() - 1);
            $lines = $linesdefault;
            $cleared = true;
        }
        else
        {
            if (@$_COOKIE['gruppenmixer'])
            {
                $lines = base64_decode($_COOKIE['gruppenmixer']); 
            }
            else
            {
                $lines = $linesdefault;
            }
        }
    }
    if (@$_POST['parts']) 
    {
        $partsaim = $_POST['parts'];
    }
    if (!$lines) {
        $state = 0;
    } 
    else if ( $state == 5 )
    {
        if ( @$_POST['circle'] )
        {
            $circle = $_POST['circle'];
            if ( count( $circle ) == @$circle[ count( $circle ) - 1 ] )
            {
                $state = 1;
                if ( @$_POST['mustdecode'] )
                {
                    $lines = base64_decode ( $lines ); 
                }
            }
        }
        else
        {
            $state = 1;
            if ( @$_POST['mustdecode'] )
            {
                $lines = base64_decode ( $lines ); 
            }
        }
    }
    
    // Now start output, 
    // but the main state switch will still be coming 
    // and also some state-dependent processing 
    // will be scattered around there...
    
?>
<html>
<head>
<title><?php echo($title); ?></title>
<script language="JavaScript">
<!--

    function partschange(sender) {
        var current;
        current = document.mainform.parts.value;
        switch(sender) {
            case 1: // down
                if (current > 1) {
                    current--;
                }
            break;
            default: // up
                current++;
        }
        document.mainform.parts.value = current;
    }
    
    function switchfield(fieldsize) {
        for ( i=0; i<fieldsize; i++ )
        {
            document.mainform.elements[i].checked 
                = document.mainform.allswitcher.checked;
        }
    }
//-->
</script>
<style>
    body { font-family: Helvetica, Arial; }
    textarea { width: 26em; height: 28em; }
    #parts { width: 2em; }
    h1 { font-size: 16pt; margin: 0 0 0.6em 0; }
    h2 { font-size: 14pt; margin: 0; }
    div.group {
        border-style: solid; 
        border-width: 1px; 
        display: inline-block; 
        padding: 0.3em 0.5em 0.3em 0.5em;
        background-color: #eee;
        margin-left: 1.2cm;
    }
    div.group h2 {
        color: #00a;
        font-size: 24pt;
    }
    ul.group {
        margin: 0; 
        padding: 0 0 0 1em; 
    }
    ul.group li {
        font-size: 36pt;
    }
    form.inline { display: inline; }
    label.command { color: gray; font-style: italic; }
    .minor { font-size: 8pt; margin-top:-1em; margin-bottom:-1em; }
    div.cmd { border-style: solid; border-width: 1px; border-color: gray; 
        display: inline-block; padding: 0 0.5em 0 0.5em; margin: 0; }
    ul.selectionlist { padding: 0 0 0 1em; list-style: none; }
    ul.selectionlist li { margin-top: -4px; }
    a.downloadlink { font-size: 10pt; color: gray; text-decoration: none; }
    a.downloadlink:hover { text-decoration: underline; }
    span.theOne {
        font-weight: bold;
        color: #f52;
    }
</style>
</head>
<body>
<h1><?php echo ( $title ); ?></h1>
<form action="index.php" method="post" name="mainform">
<?php
    switch ($state) 
    {
        case 0:
            if (@$_POST['lines']) 
            {
                $lines = $_POST['lines'];
            }
            if (@$_POST['parts']) 
            {
                $partsaim = $_POST['parts'];
            }
            if ( @$_POST['mustdecode'] ) 
            {
                $lines = base64_decode( $lines ); 
            }
?>
    <p><textarea name="lines"><?php echo($lines); ?></textarea></p>
    <div class="cmd">
        <p>
            <label for="parts"><?php echo($partslabel); ?></label>
            <script language="JavaScript">
            <!--
                document.writeln( "<button id=\"partsup\" " 
                    + "onClick=\"partschange(0); return false;\">"
                    + "<?php echo($partsup); ?></button>" );
            //-->
            </script>
            <input 
                type="text" id="parts" name="parts" 
                value="<?php echo($partsaim); ?>" />
            <script language="JavaScript">
            <!--
                document.writeln( "<button id=\"partsdown\" " 
                    + "onClick=\"partschange(1); return false;\">"
                    + "<?php echo($partsdown); ?></button>" );
            //-->
            </script>
        </p>
        <p class="minor" >
            <input type="checkbox" name="sortresult" value="1" checked />
            <label for="sortresult"><?php echo( $sortlabel ) ?></label>
        </p>
        <p>
            <input type="hidden" name="state" value="1" />
            <input 
                type="submit" 
                onClick="document.mainform.state.value=1" 
                value="<?php echo($submitstate0); ?>" 
            />
        </p>
    </div>
    <div class="cmd">
        <p>
            <script language="JavaScript">
            <!--
                document.writeln( "<button id=\"preselect\" " 
                    + "onClick=\"document.mainform.state.value=4;\">"
                    + "<?php echo( $preselection ); ?></button>" );
            //-->
            </script>
        </p>
    </div>
<?php 
        break;
        case 1:
            $sortresult = false;
            if ( @$_POST['sortresult'] ) 
            {
                $sortresult = true;
            }
            if ( isgivendata($lines, $title, $grouptitle ) )
            {
                $groups = extractgivendatagroups( 
                    trim($lines), $title, $grouptitle, $downloadme ) ;
            }
            else
            {
                $groups = linemixer( trim($lines), $partsaim, $sortresult );
                if ( @$fake ) {
                    $groups = $fake;
                }
            }
            echogroups ( $grouptitle, $groups );
            /*echo( "\t" . '<style>' . "\n\t\t" . 'div.group { width:' . 
                ((90 - 90 % count($groups)) / count($groups)) .
                '%; }' . "\n\t" . '</style>' . "\n"); */
?>
    <p>
        <input type="hidden" name="state" value="0" />
<?php
            $lines = base64_encode ( $lines ); 
            $mixed = base64_encode ( groups2string ( $groups ) );
?>
        <input type="hidden" name="lines" value="<?php echo($lines) ?>" />
        <input type="hidden" name="mustdecode" value="1" />
        <input type="hidden" name="parts" value="<?php echo($partsaim) ?>" />
        <input type="submit" value="<?php echo($submitstate1); ?>" />
        <input type="hidden" name="mixed" value="<?php echo($mixed) ?>" />
        <script language="JavaScript">
        <!--
            document.writeln( "<button id=\"partsup\" " 
                + "onClick=\"document.mainform.state.value=2;\">"
                + "<?php echo($submitpuzzler); ?></button>" );
            document.writeln( "<button id=\"partsup\" " 
                + "onClick=\"document.mainform.state.value=6;\">"
                + "<?php echo($drawone); ?></button>" );
        //-->
        </script>
    </p>
<?php
        break;
        case 2: // puzzler
            $mixed = '';
            $mixedgroup = 0;
            if ( $_POST['mixed'] )
            {
                $mixed = $_POST['mixed'];
                $mixedgroup = string2groups( base64_decode($mixed ) ); 
            }
            echogroups( $grouptitle, $mixedgroup );
            $partsaim = count ( $mixedgroup[0] );
            if ( !puzzleunique ( $mixedgroup ) ) 
            {
                $partsaim--;
            }
?>
    <p>
        <label for="parts"><?php echo($puzzlepartslabel); ?></label>
        <script language="JavaScript">
        <!--
            document.writeln( "<button id=\"partsup\" " 
                + "onClick=\"partschange(0); return false;\">"
                + "<?php echo($partsup); ?></button>" );
        //-->
        </script>
        <input 
            type="text" id="parts" name="parts" 
            value="<?php echo($partsaim); ?>" />
        <script language="JavaScript">
        <!--
            document.writeln( "<button id=\"partsdown\" " 
                + "onClick=\"partschange(1); return false;\">"
                + "<?php echo($partsdown); ?></button>" );
        //-->
        </script>
        <input type="hidden" name="state" value="3" />
        <input type="hidden" name="mustdecode" value="1" />
        <input type="hidden" name="mixed" value="<?php echo($mixed) ?>" />
        <input type="hidden" name="lines" value="<?php echo($lines) ?>" />
        <input type="submit" value="<?php echo($submitstate2); ?>" />
    </p>
<?php
        break;
        case 3:
            if (@$_POST['parts']) 
            {
                $sizeaim = $_POST['parts'];
            }
            $mixed = '';
            $mixedgroup = 0;
            if ( $_POST['mixed'] )
            {
                $mixed = $_POST['mixed'];
                $mixedgroup = string2groups( base64_decode($mixed ) ); 
            }
            if ( @$_POST['nonumber'] )
            {
?>
    <p>
        <?php 
            echo (  
                echogroups ( 
                    $grouptitle, 
                    grouppuzzler ( 
                        $mixedgroup, 
                        $sizeaim,
                        2,
                        explode("\n", base64_decode( $_POST['leaders'] ) )
                    ), 
                    1  
                )  
            ); 
        ?>
<?php
            }
            else
            {
?>
    <p>
        <?php echo (  echogroups ( $grouptitle, grouppuzzler ( $mixedgroup, $sizeaim ), 1  )  ); ?>
<?php
            }
?>
    </p><p>
        <input type="hidden" name="state" value="0" />
        <input type="hidden" name="mustdecode" value="1" />
        <input type="hidden" name="lines" value="<?php echo($lines) ?>" />
        <input type="submit" value="<?php echo($submitstate1); ?>" />    
    </p>
<?php
        break;
        case 4:
            $members = explode ( "\n", trim ( $lines ) ); 
            $membercount = 0;
?>
        <ul class="selectionlist">
<?php
            foreach ( $members as $member ) 
            {
?>
        <li>
            <input  
                type="checkbox" name="circle[]" 
                value="<?php echo ( ($membercount + 1) ); ?>"
            />
            <label for="circle"><?php echo ( trim($member) ); ?></label>
        </li>
<?php
                $membercount++;
            }
            if ( $membercount > 1 ) 
            {
?>
        <script language="JavaScript">
        <!--
            document.writeln( 
                    "<li>"
                + "<label for=\"circle\" class=\"command\">"
                + "<?php echo ( $allmembers ); ?></label> "
                + "<input type=\"checkbox\" value=\"0\" "
                + "name=\"allswitcher\" onClick=\"switchfield("
                + "<?php echo ( $membercount ); ?>);\" />"
                + "</li>" );
        //-->
        </script>
<?php
            }
?>
        </ul>
        <input type="hidden" name="state" value="5" />
        <input type="hidden" name="mustdecode" value="1" />
        <input type="hidden" name="lines" value="<?php echo( base64_encode( $lines ) ) ?>" />
        <input type="submit" value="<?php echo($submitstate3); ?>" />
<?php
        break;
        case 5:
            $lines = base64_decode ( $lines ); 
?>
        <ul class="selectionlist">
<?php
            $members = explode ( "\n", trim ($lines) );
            $membercount = 0;
            $selectedmembers = array();
            foreach ( $members as $member ) 
            {
                if ( in_array ( ( $membercount + 1 ), $circle ) )
                {
                    $selectedmembers[] = $member; 
                }
                $membercount++;
            }
            $membercount = 0;
            $unselectedmembers = array();
            foreach ( $members as $member ) 
            {
                if ( !in_array ( ( $membercount + 1 ), $circle ) )
                {
                    $unselectedmembers[] = $member; 
                }
                $membercount++;
            }
            $partsaim = 0;
            $newmix = array();
            $newmix[0] = array();
            shuffle($selectedmembers);
            shuffle($unselectedmembers);
            foreach ( $selectedmembers as $member ) 
            {
                $newmix[0][] = $member; 
                echo ('<li style="font-weight: bold">' . $member . '</li>');
                $partsaim++;
            }
            foreach ( $unselectedmembers as $member ) 
            {
                $newmix[0][] = $member; 
                echo ('<li>' . $member . '</li>');
            }            
            $mixed = base64_encode ( groups2string ( $newmix ) );
            $leaders = base64_encode ( join ("\n", $selectedmembers) );
?> 
        </ul>
        <label for="parts"><?php echo($circlepartslabel); ?></label>
        <script language="JavaScript">
        <!--
            document.writeln( "<button id=\"partsup\" " 
                + "onClick=\"partschange(0); return false;\">"
                + "<?php echo($partsup); ?></button>" );
        //-->
        </script>
        <input 
            type="text" id="parts" name="parts" 
            value="<?php echo($partsaim); ?>" />
        <script language="JavaScript">
        <!--
            document.writeln( "<button id=\"partsdown\" " 
                + "onClick=\"partschange(1); return false;\">"
                + "<?php echo($partsdown); ?></button>" );
        //-->
        </script>
        <input type="hidden" name="state" value="3" />
        <input type="hidden" name="mustdecode" value="1" />
        <input type="hidden" name="lines" value="<?php echo( base64_encode( $lines ) ) ?>" />
        <input type="hidden" name="mixed" value="<?php echo( $mixed ) ?>" />
        <input type="hidden" name="leaders" value="<?php echo( $leaders ) ?>" />
        <input type="hidden" name="sortresult" value="0" />
        <input type="hidden" name="nonumber" value="1" />
        <input type="submit" value="<?php echo($submitstate2); ?>" />
<?php
        break;
        case 6:
            $mixed = '';
            $mixedgroup = 0;
            if ( $_POST['mixed'] )
            {
                $mixed = $_POST['mixed'];
                $mixedgroup = string2groups( base64_decode($mixed ) ); 
            }
            $drawone = true;
            if ( @$fake2 ) 
            {
                $drawone = $fake2;
            }
            echogroups( $grouptitle, $mixedgroup, 0, $drawone );
?>
    <p>
        <input type="hidden" name="state" value="0" />
        <input type="hidden" name="mustdecode" value="1" />
        <input type="hidden" name="lines" value="<?php echo($lines) ?>" />
        <input type="submit" value="<?php echo($submitstate1); ?>" />    
    </p>
<?php
        break;
    }
?>
</form>
<?php
    if (@$_COOKIE['gruppenmixer']) 
    {
        if (!$cleared) 
        {
?>
<form action="<?php echo ( basename( __FILE__) ); ?>" name="clearcookieform" method="post">
    <input type="hidden" name="lines" value="0" />
    <input type="hidden" name="state" value="0" />
    <input type="hidden" name="clearcookie" value="1" />
    <input type="submit" value="<?php echo( $deletedata ); ?>" />
</form>
<?php
        }
    }
?>
<a class="downloadlink" href="index.php?download=1" 
    target="_blank" title="<?php echo ( $downloadme ); ?>">
        <?php echo ( $downloadme ); ?>
</a>
</body>
</html>