root/geowiki/getcolourxml.rs.php

<?php 
require("jsrsServer.php.inc");
//getColourXML($filename, $dataset, $nrColours, $rangeValues)
jsrsDispatch("getcolourxml");

//makes an array out of $string and trims it
function getTrimmedArray($separator, $string) {
    $tmp = explode($separator, $string);
    for ($i = 0; $i < count($tmp); $i++)
        $tmp[$i] = trim($tmp[$i]);
    return $tmp;
}

//$values is an array which contains ordered values that define ranges
//e.g. [32, 18, 7, 3.5] defining ranges of different levels of alcoholic drinks
//(.., 32] hard liquor, (32, 18], (18, 7] wine, (7, 3.5] beer, (3.5, ..) non alcoholic
//return value is the range's number in which $value falls
//e.g. 0 for anything >= 32, 1 below 32 down to 18, or 4 for $value<3.5
function getColourTag($values, $value) {
    $i = 0;
    while ((count($values) > $i) && ($value < $values[$i]))
        $i++;
    return "<category>colour$i</category>";
}

//TODO: make use of $nrColours
//reads the data from rss.xml or any file given in $filename
//$dataset: a string containing (uid,value) pairs, separated by newline
//$nrColours: number of predefined colours as categories in config.xml (or
//any smaller number); if < 1 will be set to 1
//$rangeValues: comma-separated values, defining the ranges for each colour
//if empty, the interval between maximum and minimum value in $dataset
//is separated into $nrColours equal ranges
//returns the name of a temporary file, which contains the items of the original
//file. Each of the items whose uids are within $dataset is tagged by the
//predefined colour according to the value in $dataset
//Example:
//rss = getColourXML("rss.xml","Sterni Export,5.5\nAbsolut,42",4,"32,18,7,3.5");
//rss will contain the content from rss.xml, with added categories <colour3>
//and <colour0> for the respective drinks
function getcolourxml($filename, $dataset, $nrColours, $rangeValues = '') {
    //organise dataset, find max and min value
    $tmp = getTrimmedArray("\n", $dataset);
    foreach ($tmp as $dataPair) {
        $pair = explode(",", $dataPair);
        $uid = $pair[0];
        $value = $pair[1];
        $values[$uid] = $value;

        //find min and max values
        if (!isset($vMin)) {
            $vMin = $value;
            $vMax = $value;
        }
        if ($value < $vMin) $vMin = $value;
        else if ($value > $vMax) $vMax = $value;
    }
    
    var_dump($values);
    
    //TODO
    //if $rangeValues empty create it by dividing (vMin,vMax) into $nrColours
    //equal intervals
    //TODO: init $rangeArray
    if ($rangeValues == '') {
        if ($nrColours < 1)
            $nrColours = 1;
        $step = ($vMax - $vMin) / $nrColours;
        for ($i=1; $i <= $nrColours; $i++) {
            $rangeArray[] = $vMax - $i * $step;
        }
    }
    else {
        $rangeArray = explode(",", $rangeValues);
        rsort($rangeArray);
    }
    
    //read file
    $handle = fopen($filename,"r");
    $contents = fread($handle, filesize($filename));
    fclose($handle);
    
    //for each uid in dataset: read xml, add relevant colour tag
    //TODO: use xml-parsing functions
    foreach ($values as $uid => $value) {
        //find uid
        $pos = strpos($contents, "<guid>$uid</guid>");
        echo "pos: ", $pos;
        //=== is essential!
        if ($pos === false) continue;
        
        $itemEndPos = strpos($contents, "</item>", $pos);

        //define colour
        $colourTag = getColourTag($rangeArray, $value);
        
        //add tag to item
        $contents = substr_replace($contents, $colourTag, $itemEndPos, 0);
    }

    //write to temporary file
    $tmpName = "temprss.xml";

    $handle = fopen($tmpName, "w");
    fwrite($handle, $contents);
    fclose($handle);

    return $tmpName;
}

echo getcolourxml("rss.xml","Ulsoor Lake, 4\nHAL, 10","4","100, 80, 30, 5");
echo getcolourxml("rss.xml","Ulsoor Lake, 4\nHAL, 10\nIndiranagar Park, 7","4","");

?>