<?php // -*-php-*-
rcs_id('$Id: VisualWiki.php,v 1.11 2004-09-06 10:10:27 rurban Exp $');
/*
 Copyright (C) 2002 Johannes Große (Johannes Gro&szlig;e)

 This file is (not yet) part of PhpWiki.

 PhpWiki is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 2 of the License, or
 (at your option) any later version.

 PhpWiki is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with PhpWiki; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/**
 * Produces graphical site map of PhpWiki
 * Example for an image map creating plugin. It produces a graphical
 * sitemap of PhpWiki by calling the <code>dot</code> commandline tool
 * from graphviz (http://www.graphviz.org).
 * @author Johannes Große
 * @version 0.8
 */
define('VISUALWIKI_ALLOWOPTIONS', true);
global $dotbin;
if (PHP_OS == "Darwin") { // Mac OS X
    $dotbin = '/sw/bin/dot'; // graphviz via Fink
    //$dotbin = '/usr/local/bin/dot';

    // Name of the Truetypefont - at least LucidaSansRegular.ttf is always present on OS X
    define('VISUALWIKIFONT', 'LucidaSansRegular');

    // The default font paths do not find your fonts, set the path here:
    $fontpath = "/System/Library/Frameworks/JavaVM.framework/Versions/1.3.1/Home/lib/fonts/";
    //$fontpath = "/usr/X11R6/lib/X11/fonts/TTF/";
}
elseif (isWindows()) {
  $dotbin = 'dot';
  define('VISUALWIKIFONT', 'Arial');
} else { // other os
    $dotbin = '/usr/local/bin/dot';
    // $dotbin = '/home/groups/p/ph/phpwiki/bin/dot';

    // Name of the Truetypefont - Helvetica is probably easier to read
    //define('VISUALWIKIFONT', 'Helvetica');
    //define('VISUALWIKIFONT', 'Times');
    //define('VISUALWIKIFONT', 'Arial');
    define('VISUALWIKIFONT', 'luximr'); // sf.net, sf.net can only do gif

    // The default font paths do not find your fonts, set the path here:
    //$fontpath = "/usr/X11R6/lib/X11/fonts/TTF/";
    //$fontpath = "/usr/share/fonts/default/TrueType/";
}

if (!defined('VISUALWIKI_ALLOWOPTIONS'))
    define('VISUALWIKI_ALLOWOPTIONS', false);

require_once "lib/WikiPluginCached.php";

class WikiPlugin_VisualWiki
extends WikiPluginCached
{
    /**
     * Sets plugin type to map production
     */
    function getPluginType() {
        return PLUGIN_CACHED_MAP;
    }

    /**
     * Sets the plugin's name to VisualWiki. It can be called by
     * <code>&lt;?plugin VisualWiki?&gt;</code>, now. This
     * name must correspond to the filename and the class name.
     */
    function getName() {
        return "VisualWiki";
    }

    function getVersion() {
        return preg_replace("/[Revision: $]/", '',
                            "\$Revision: 1.11 $");
    }

    /**
     * Sets textual description.
     */
    function getDescription() {
        return _("Visualizes the Wiki structure in a graph using the 'dot' commandline tool from graphviz.");
    }

    /**
     * Returns default arguments. This is put into a separate
     * function to allow its usage by both <code>getDefaultArguments</code>
     * and <code>checkArguments</code>
     */
    function defaultarguments() {
        return array('imgtype'        => 'png',
                     'width'          => 5,
                     'height'         => 7,
                     'colorby'        => 'age', // sort by 'age' or 'revtime'
                     'fillnodes'      => 'off',
                     'label'          => 'name',
                     'shape'          => 'ellipse',
                     'large_nb'       => 5,
                     'recent_nb'      => 5,
                     'refined_nb'     => 15,
                     'backlink_nb'    => 5,
                     'neighbour_list' => '',
                     'exclude_list'   => '',
                     'include_list'   => '',
                     'fontsize'       => 10,
                     'debug'          => false,
                     'help'           => false );
    }

    /**
     * Sets the default arguments. WikiPlugin also regards these as
     * the allowed arguments. Since WikiPluginCached stores an image
     * for each different set of parameters, there can be a lot of
     * these (large) graphs if you allow different parameters.
     * Set <code>VISUALWIKI_ALLOWOPTIONS</code> to <code>false</code>
     * to allow no options to be set and use only the default paramters.
     * This will need an disk space of about 20 Kbyte all the time.
     */
    function getDefaultArguments() {
        if (VISUALWIKI_ALLOWOPTIONS)
            return $this->defaultarguments();
        else
            return array();
    }

    /**
     * Substitutes each forbidden parameter value by the default value
     * defined in <code>defaultarguments</code>.
     */
    function checkArguments(&$arg) {
        extract($arg);
        $def = $this->defaultarguments();

        if (($width < 3) || ($width > 15))
            $arg['width'] = $def['width'];

        if (($height < 3) || ($height > 20))
            $arg['height'] = $def['height'];

        if (($fontsize < 8) || ($fontsize > 24))
            $arg['fontsize'] = $def['fontsize'];

        if (!in_array($label, array('name', 'number')))
            $arg['label'] = $def['label'];

        if (!in_array($shape, array('ellipse', 'box', 'point', 'circle',
                                    'plaintext')))
            $arg['shape'] = $def['shape'];

        if (!in_array($colorby, array('age', 'revtime')))
            $arg['colorby'] = $def['colorby'];

        if (!in_array($fillnodes, array('on', 'off')))
            $arg['fillnodes'] = $def['fillnodes'];

        if (($large_nb < 0) || ($large_nb > 50))
            $arg['large_nb'] = $def['large_nb'];

        if (($recent_nb < 0)  || ($recent_nb > 50))
            $arg['recent_nb'] = $def['recent_nb'];

        if (($refined_nb < 0 ) || ( $refined_nb > 50))
            $arg['refined_nb'] = $def['refined_nb'];

        if (($backlink_nb < 0) || ($backlink_nb > 50))
            $arg['backlink_nb'] = $def['backlink_nb'];

        // ToDo: check if "ImageCreateFrom$imgtype"() exists.
        if (!in_array($imgtype, $GLOBALS['PLUGIN_CACHED_IMGTYPES']))
            $arg['imgtype'] = $def['imgtype'];
        if (empty($fontname))
            $arg['fontname'] = VISUALWIKIFONT;
    }

    /**
     * Checks options, creates help page if necessary, calls both
     * database access and image map production functions.
     * @return array($map,$html)
     */
    function getMap($dbi, $argarray, $request) {
        if (!VISUALWIKI_ALLOWOPTIONS)
            $argarray = $this->defaultarguments();
        $this->checkArguments($argarray);
        //extract($argarray);
        if ($argarray['help'])
            return array($this->helpImage(), ' '); // FIXME
        $this->createColors();
        $this->extract_wikipages($dbi, $argarray);
        /* ($dbi,  $large, $recent, $refined, $backlink,
            $neighbour, $excludelist, $includelist, $color); */
        return $this->invokeDot($argarray);
        /* ($width, $height, $color, $shape, $text); */
    }

    /**
     * Sets the expire time to one day (so the image producing
     * functions are called seldomly) or to about two minutes
     * if a help screen is created.
     */
    function getExpire($dbi, $argarray, $request) {
        if ($argarray['help'])
            return '+120'; // 2 minutes
        return sprintf('+%d', 3*86000); // approx 3 days
    }

    /**
     * Sets the imagetype according to user wishes and
     * relies on WikiPluginCached to catch illegal image
     * formats.
     * (I feel unsure whether this option is reasonable in
     *  this case, because png will definitely have the
     *  best results.)
     *
     * @return string 'png', 'gif', 'jpeg'
     */
    function getImageType($dbi, $argarray, $request) {
        return $argarray['imgtype'];
    }

    /**
     * This gives an alternative text description of
     * the image map. I do not know whether it interferes
     * with the <code>title</code> attributes in &lt;area&gt;
     * tags of the image map. Perhaps this will be removed.
     * @return string
     */
    function getAlt($dbi, $argstr, $request) {
        return $this->getDescription();
    }

    // ------------------------------------------------------------------------------------------

    /**
     * Returns an image containing a usage description of the plugin.
     * @return string image handle
     */
    function helpImage() {
        $def = $this->defaultarguments();
        $other_imgtypes = $GLOBALS['PLUGIN_CACHED_IMGTYPES'];
        unset ($other_imgtypes[$def['imgtype']]);
        $helparr = array(
            '<?plugin '.$this->getName() .
            ' img'             => ' = "' . $def['imgtype'] . "(default)|" . join('|',$GLOBALS['PLUGIN_CACHED_IMGTYPES']).'"',
            'width'            => ' = "width in inches"',
            'height'           => ' = "height in inches"',
            'fontname'         => ' = "font family"',
            'fontsize'         => ' = "fontsize in points"',
            'colorby'          => ' = "age|revtime|none"',
            'fillnodes'        => ' = "on|off"',
            'shape'            => ' = "ellipse(default)|box|circle|point"',
            'label'            => ' = "name|number"',
            'large_nb'         => ' = "number of largest pages to be selected"',
            'recent_nb'        => ' = "number of youngest pages"',
            'refined_nb'       => ' = "#pages with smallest time between revisions"',
            'backlink_nb'      => ' = "number of pages with most backlinks"',
            'neighbour_list'   => ' = "find pages linked from and to these pages"',
            'exclude_list'     => ' = "colon separated list of pages to be excluded"',
            'include_list'     => ' = "colon separated list"     ?>'
            );
        $length = 0;
        foreach($helparr as $alignright => $alignleft) {
            $length = max($length, strlen($alignright));
        }
        $helptext ='';
        foreach($helparr as $alignright => $alignleft) {
            $helptext .= substr('                                                        '
                                . $alignright, -$length).$alignleft."\n";
        }
        return $this->text2img($helptext, 4, array(1, 0, 0),
                               array(255, 255, 255));
    }


    /**
     * Selects the first (smallest or biggest) WikiPages in
     * a given category.
     *
     * @param  number   integer  number of page names to be found
     * @param  category string   attribute of the pages which is used
     *                           to compare them
     * @param  minimum  boolean  true finds smallest, false finds biggest
     * @return array             list of page names found to be the best
     */
    function findbest($number, $category, $minimum ) {
        // select the $number best in the category '$category'
        $pages = &$this->pages;
        $names = &$this->names;

        $selected = array();
        $i = 0;
        foreach($names as $name) {
            if ($i++>=$number)
                break;
            $selected[$name] = $pages[$name][$category];
        }
        //echo "<pre>$category "; var_dump($selected); "</pre>";
        $compareto = $minimum ? 0x79999999 : -0x79999999;

        $i = 0;
        foreach ($names as $name) {
            if ($i++<$number)
                continue;
            if ($minimum) {
                if (($crit = $pages[$name][$category]) < $compareto) {
                    $selected[$name] = $crit;
                    asort($selected, SORT_NUMERIC);
                    array_pop($selected);
                    $compareto = end($selected);
                }
            } elseif (($crit = $pages[$name][$category]) > $compareto)  {
                $selected[$name] = $crit;
                arsort($selected, SORT_NUMERIC);
                array_pop($selected);
                $compareto = end($selected);
            }
        }
        //echo "<pre>$category "; var_dump($selected); "</pre>";

        return array_keys($selected);
    }


    /**
    * Extracts a subset of all pages from the wiki and find their
    * connections to other pages. Also collects some page features
    * like size, age, revision number which are used to find the
    * most attractive pages.
    *
    * @param  dbi         WikiDB   database handle to access all Wiki pages
    * @param  LARGE       integer  number of largest pages which should
    *                              be included
    * @param  RECENT      integer  number of the youngest pages to be included
    * @param  REFINED     integer  number of the pages with shortes revision
    *                              interval
    * @param  BACKLINK    integer  number of the pages with most backlinks
    * @param  EXCLUDELIST string   colon ':' separated list of page names which
    *                              should not be displayed (like PhpWiki, for
    *                              example)
    * @param  INCLUDELIST string   colon separated list of pages which are
    *                              allways included (for example your own
    *                              page :)
    * @param  COLOR       string   'age', 'revtime' or 'none'; Selects which
    *                              page feature is used to determine the
    *                              filling color of the nodes in the graph.
    * @return void
    */
    function extract_wikipages($dbi, $argarray) {
        // $LARGE, $RECENT, $REFINED, $BACKLINK, $NEIGHBOUR,
        // $EXCLUDELIST, $INCLUDELIST,$COLOR
        $now = time();

        extract($argarray);
        // FIXME: gettextify?
        $exclude_list   = explode(':', $exclude_list);
        $include_list   = explode(':', $include_list);
        $neighbour_list = explode(':', $neighbour_list);

        // FIXME remove INCLUDED from EXCLUDED

        // collect all pages
        $allpages = $dbi->getAllPages();
        $pages = &$this->pages;
        $countpages = 0;
        while ($page = $allpages->next()) {
            $name = $page->getName();

            // skip exluded pages
            if (in_array($name, $exclude_list)) continue;

            // false = get links from actual page
            // true  = get links to actual page ("backlinks")
            $backlinks = $page->getLinks(true);
            unset($bconnection);
            $bconnection = array();
            while ($blink = $backlinks->next()) {
                array_push($bconnection, $blink->getName());
            }
            unset($backlinks);

            // include all neighbours of pages listed in $NEIGHBOUR
            if (in_array($name,$neighbour_list)) {
                $l = $page->getLinks(false);
                $con = array();
                while ($link = $l->next()) {
                    array_push($con, $link->getName());
                }
                $include_list = array_merge($include_list, $bconnection, $con);
                unset($l);
                unset($con);
            }

            unset($currev);
            $currev = $page->getCurrentRevision();

            $pages[$name] = array(
                'age'         => $now-$currev->get('mtime'),
                'revnr'       => $currev->getVersion(),
                'links'       => array(),
                'backlink_nb' => count($bconnection),
                'backlinks'   => $bconnection,
                'size'        => 1000 // FIXME
                );
            $pages[$name]['revtime'] = $pages[$name]['age'] / ($pages[$name]['revnr']);

            unset($page);
        }
        unset($allpages);
        $this->names = array_keys($pages);

        $countpages = count($pages);

        // now select each page matching to given parameters
        $all_selected = array_unique(array_merge(
            $this->findbest($recent_nb,   'age',         true),
            $this->findbest($refined_nb,  'revtime',     true),
            $x = $this->findbest($backlink_nb, 'backlink_nb', false),
//            $this->findbest($large_nb,    'size',        false),
            $include_list));

        foreach($all_selected as $name)
            if (isset($pages[$name]))
                $newpages[$name] = $pages[$name];
        unset($this->names);
        unset($this->pages);
        $this->pages = $newpages;
        $pages = &$this->pages;
        $this->names = array_keys($pages);
        unset($newpages);
        unset($all_selected);

        $countpages = count($pages);

        // remove dead links and collect links
        reset($pages);
        while( list($name,$page) = each($pages) ) {
            if (is_array($page['backlinks'])) {
                reset($page['backlinks']);
                while ( list($index, $link) = each( $page['backlinks'] ) ) {
                    if ( !isset($pages[$link]) || $link == $name ) {
                        unset($pages[$name]['backlinks'][$index]);
                    } else {
                        array_push($pages[$link]['links'],$name);
                        //array_push($this->everylink, array($link,$name));
                    }
                }
            }
        }

        if ($colorby == 'none')
            return;
        list($oldestname) = $this->findbest(1, $colorby, false);
        $this->oldest = $pages[$oldestname][$colorby];
        foreach($this->names as $name)
            $pages[$name]['color'] = $this->getColor($pages[$name][$colorby] / $this->oldest);
    } // extract_wikipages

    /**
     * Creates the text file description of the graph needed to invoke
     * <code>dot</code>.
     *
     * @param filename  string  name of the dot file to be created
     * @param width     float   width of the output graph in inches
     * @param height    float   height of the graph in inches
     * @param colorby   string  color sceme beeing used ('age', 'revtime',
     *                                                   'none')
     * @param shape     string  node shape; 'ellipse', 'box', 'circle', 'point'
     * @param label     string  'name': label by name,
     *                          'number': label by unique number
     * @return boolean          error status; true=ok; false=error
     */
    function createDotFile($filename, $argarray) {
        extract($argarray);
        if (!$fp = fopen($filename, 'w'))
            return false;

        $fillstring = ($fillnodes == 'on') ? 'style=filled,' : '';

        $ok = true;
        $names = &$this->names;
        $pages = &$this->pages;

        $nametonumber = array_flip($names);

        $dot = "digraph VisualWiki {\n" // }
             . (!empty($fontpath) ? "    fontpath=\"$fontpath\"\n" : "")
             . "    size=\"$width,$height\";\n    ";

        switch ($shape) {
        case 'point':
            $dot .= "edge [arrowhead=none];\nnode [shape=$shape,fontname=$fontname,width=0.15,height=0.15,fontsize=$fontsize];\n";
            break;
        case 'box':
            $dot .= "node [shape=$shape,fontname=$fontname,width=0.4,height=0.4,fontsize=$fontsize];\n";
            break;
        case 'circle':
            $dot .= "node [shape=$shape,fontname=$fontname,width=0.25,height=0.25,fontsize=$fontsize];\n";
            break;
        default :
            $dot .= "node [fontname=$fontname,shape=$shape,fontsize=$fontsize];\n" ;
        }
        $dot .= "\n";
        $i = 0;
        foreach ($names as $name) {

            $url = rawurlencode($name);
            // patch to allow Page/SubPage
            $url = preg_replace('/' . urlencode(SUBPAGE_SEPARATOR) . '/',
                                SUBPAGE_SEPARATOR, $url);
            $nodename = ($label != 'name' ? $nametonumber[$name] + 1 : $name);

            $dot .= "    \"$nodename\" [URL=\"$url\"";
            if ($colorby != 'none') {
                $col = $pages[$name]['color'];
                $dot .= sprintf(',%scolor="#%02X%02X%02X"', $fillstring,
                                $col[0], $col[1], $col[2]);
            }
            $dot .= "];\n";

            if (!empty($pages[$name]['links'])) {
                unset($linkarray);
                if ($label != 'name')
                    foreach($pages[$name]['links'] as $linkname)
                        $linkarray[] = $nametonumber[$linkname] + 1;
                else
                    $linkarray = $pages[$name]['links'];
                $linkstring = join('"; "', $linkarray );

                $c = count($pages[$name]['links']);
                $dot .= "        \"$nodename\" -> "
                     . ($c>1?'{':'')
                     . "\"$linkstring\";"
                     . ($c>1?'}':'')
                     . "\n";
            }
        }
        if ($colorby != 'none') {
            $dot .= "\n    subgraph cluster_legend {\n"
                 . "         node[fontname=$fontname,shape=box,width=0.4,height=0.4,fontsize=$fontsize];\n"
                 . "         fillcolor=lightgrey;\n"
                 . "         style=filled;\n"
                 . "         fontname=$fontname;\n"
                 . "         fontsize=$fontsize;\n"
                 . "         label=\"".gettext("Legend")."\";\n";
            $oldest= ceil($this->oldest / (24 * 3600));
            $max = 5;
            $legend = array();
            for($i = 0; $i < $max; $i++) {
                $time = floor($i / $max * $oldest);
                $name = '"' . $time .' '. _("days") .'"';
                $col = $this->getColor($i/$max);
                $dot .= sprintf('       %s [%scolor="#%02X%02X%02X"];',
                                $name, $fillstring, $col[0], $col[1], $col[2])
                    . "\n";
                $legend[] = $name;
            }
            $dot .= '        '. join(' -> ', $legend)
                 . ";\n    }\n";

        }

        // {
        $dot .= "}\n";

        $ok = fwrite($fp, $dot);
        $ok = fclose($fp) && $ok;  // close anyway

        return $ok;
    }

    /**
     * Execute system command.
     *
     * @param  cmd string   command to be invoked
     * @return     boolean  error status; true=ok; false=error
     */
    function execute($cmd) {
        exec($cmd, $outarr, $returnval); // normally 127
        $errstr = join('',$outarr);
        if (!empty($errstr))
            trigger_error($cmd.": ".$errstr, E_USER_WARNING);
        if (!isWindows())
            usleep(1000);
        return empty($errstr);
    }

    /**
     * Produces a dot file, calls dot twice to obtain an image and a
     * text description of active areas for hyperlinking and returns
     * an image and an html map.
     *
     * @param width     float   width of the output graph in inches
     * @param height    float   height of the graph in inches
     * @param colorby   string  color sceme beeing used ('age', 'revtime',
     *                                                   'none')
     * @param shape     string  node shape; 'ellipse', 'box', 'circle', 'point'
     * @param label     string  not used anymore
     */
    function invokeDot($argarray) {
        global $dotbin;
        //$cacheparams = $GLOBALS['CacheParams'];
        $tempfiles = $this->tempnam('VisualWiki');
        $gif = $argarray['imgtype'];
        $ImageCreateFromFunc = "ImageCreateFrom$gif";
        $ok =  $tempfiles
            && $this->createDotFile($tempfiles.'.dot',$argarray)
            && $this->execute("$dotbin -T$gif $tempfiles.dot -o $tempfiles.$gif")
            && $this->execute("$dotbin -Timap $tempfiles.dot -o $tempfiles.map")
            && file_exists( "$tempfiles.$gif" )
            && file_exists( $tempfiles.'.map' )
            && ($img = $ImageCreateFromFunc( "$tempfiles.$gif" ))
            && ($fp = fopen($tempfiles.'.map','r'));

        $map = HTML();
        if ($ok) {
            while (!feof($fp)) {
                $line = fgets($fp, 1000);
                if (substr($line, 0, 1) == '#')
                    continue;
                list($shape, $url, $e1, $e2, $e3, $e4) = sscanf($line,
                                                                "%s %s %d,%d %d,%d");
                if ($shape != 'rect')
                    continue;

                // dot sometimes gives not allways the right order so
                // so we have to sort a bit
                $x1 = min($e1, $e3);
                $x2 = max($e1, $e3);
                $y1 = min($e2, $e4);
                $y2 = max($e2, $e4);
                $map->pushContent(HTML::area(array(
                            'shape'  => 'rect',
                            'coords' => "$x1,$y1,$x2,$y2",
                            'href'   => $url,
                            'title'  => rawurldecode($url),
                            'alt' => $url)));
                }
            fclose($fp);
//trigger_error("url=".$url);
        } else {
            trigger_error("
$tempfiles.$gif: ".(file_exists("$tempfiles.$gif") ? filesize("$tempfiles.$gif"):'missing')."
$tempfiles.map: ".(file_exists("$tempfiles.map") ? filesize("$tempfiles.map"):'missing')."
",E_USER_WARNING);
        }

        // clean up tempfiles
        if ($ok or !$argarray['debug'])
        foreach (array('',".$gif",".map",".dot") as $ext) {
            if (file_exists($tempfiles.$ext))
                unlink($tempfiles.$ext);
        }

        if ($ok)
            return array($img, $map);
        else
            return array(false, false);
    } // invokeDot

    /**
     * Prepares some rainbow colors for the nodes of the graph
     * and stores them in an array which may be accessed with
     * <code>getColor</code>.
     */
    function createColors() {
        $predefcolors = array(
             array('red' => 255, 'green' =>   0, 'blue' =>   0),
             array('red' => 255, 'green' => 255, 'blue' =>   0),
             array('red' =>   0, 'green' => 255, 'blue' =>   0),
             array('red' =>   0, 'green' => 255, 'blue' => 255),
             array('red' =>   0, 'green' =>   0, 'blue' => 255),
             array('red' => 100, 'green' => 100, 'blue' => 100)
             );

        $steps = 2;
        $numberofcolors = count($predefcolors) * $steps;

        $promille = -1;
        foreach($predefcolors as $color) {
            if ($promille < 0) {
                $oldcolor = $color;
                $promille = 0;
                continue;
            }
            for ($i = 0; $i < $steps; $i++)
                $this->ColorTab[++$promille / $numberofcolors * 1000] = array(
                    floor(interpolate( $oldcolor['red'],   $color['red'],   $i/$steps )),
                    floor(interpolate( $oldcolor['green'], $color['green'], $i/$steps )),
                    floor(interpolate( $oldcolor['blue'],  $color['blue'],  $i/$steps ))
                );
            $oldcolor = $color;
        }
//echo"<pre>";  var_dump($this->ColorTab); echo "</pre>";
    }

    /**
     * Translates a value from 0.0 to 1.0 into rainbow color.
     * red -&gt; orange -&gt; green -&gt; blue -&gt; gray
     *
     * @param promille float value between 0.0 and 1.0
     * @return array(red,green,blue)
     */
    function getColor($promille) {
        foreach( $this->ColorTab as $pro => $col ) {
            if ($promille*1000 < $pro)
                return $col;
        }
        $lastcol = end($this->ColorTab);
        return $lastcol;
    } // getColor
} // WikiPlugin_VisualWiki

/**
 * Linear interpolates a value between two point a and b
 * at a value pos.
 * @return float  interpolated value
 */

function interpolate($a, $b, $pos) {
    return $a + ($b - $a) * $pos;
}

// $Log: not supported by cvs2svn $
// Revision 1.10  2004/06/19 10:06:38  rurban
// Moved lib/plugincache-config.php to config/*.ini
// use PLUGIN_CACHED_* constants instead of global $CacheParams
//
// Revision 1.9  2004/06/03 09:40:57  rurban
// WikiPluginCache improvements
//
// Revision 1.8  2004/01/26 09:18:00  rurban
// * changed stored pref representation as before.
//   the array of objects is 1) bigger and 2)
//   less portable. If we would import packed pref
//   objects and the object definition was changed, PHP would fail.
//   This doesn't happen with an simple array of non-default values.
// * use $prefs->retrieve and $prefs->store methods, where retrieve
//   understands the interim format of array of objects also.
// * simplified $prefs->get() and fixed $prefs->set()
// * added $user->_userid and class '_WikiUser' portability functions
// * fixed $user object ->_level upgrading, mostly using sessions.
//   this fixes yesterdays problems with loosing authorization level.
// * fixed WikiUserNew::checkPass to return the _level
// * fixed WikiUserNew::isSignedIn
// * added explodePageList to class PageList, support sortby arg
// * fixed UserPreferences for WikiUserNew
// * fixed WikiPlugin for empty defaults array
// * UnfoldSubpages: added pagename arg, renamed pages arg,
//   removed sort arg, support sortby arg
//
// Revision 1.7  2003/03/03 13:57:31  carstenklapp
// Added fontpath (see PhpWiki:VisualWiki), tries to be smart about which OS.
// (This plugin still doesn't work for me on OS X, but at least image files
// are actually being created now in '/tmp/cache'.)
//
// Revision 1.6  2003/01/18 22:11:45  carstenklapp
// Code cleanup:
// Reformatting & tabs to spaces;
// Added copyleft, getVersion, getDescription, rcs_id.
//

// Local Variables:
// mode: php
// tab-width: 8
// c-basic-offset: 4
// c-hanging-comment-ender-p: nil
// indent-tabs-mode: nil
// End:
?>