Template:SiteTagCloud

// SiteTagCloud template, by neilw and maphew, 2009
// Versions
//    1.0.0    10/06/09    neilw    Quick hack based on maphew's TagCloud template
//    1.0.1    11/05/09    neilw    Small bug fix
//    1.1.0    11/06/09    neilw    Refactored arguments, added "align" arg and error messages
//    1.2.0b   12/02/09    neilw    Added ability to search only within specified subtree
//    1.2.1    12/11/09    neilw    Added "exclude" capability back in (whoops)
//    1.3.0    3/4/2010    neilw    Made "path" parameter case-insensitive
//                                  Gracefully handle case when there are no tags
//
// This template is derived from maphew's TagCloud template.  It is optimized for
// providing a tag cloud for an entire site; performance is reasonable even with a large number
// of tags on the site.  I have refactored the way the arguments work to my own taste, and also
// added extensive error checking and reporting on the args.
//
// USAGE: SiteTagCloud( order, max, color, size, sizeUnits, exclude, showCount, align, path );
//    order: str (valid values: "name" or "count") (default "count")
//        Specifies how the tags are sorted in the list
//    max: num (default:50)
//        Specifies the maximum number of tags to be displayed.  0 ==> show all tags
//    color: list (default: [ [50,200,50], [50,100,50] ])
//        Specifies the color range for displayed tags.  May be either a single list of [r,g,b]
//        (in which case all tags will be that color) or a list of two [r,b,g] lists, where tags
//        with the fewest occurrences will be shown in the first color, and tags with the most
//        occurrences will be shown with the second color.  Other numbers of occurrences will be
//        interpolated between the two.
//    size: num or list (default: [80,240])
//        Specifies the size range for displayed tags.  If a single number is specified, all tags
//        will shown in that size.  If a list of two numbers is specified, then the tags with fewest
//        occurrences will be shown in the first size, and those with the most will be shown in the 
//        second.  Others will be interpolated in between.
//    sizeUnits: str (default: "%")
//        CSS units for the size argument.
//    exclude: str or list (default: [])
//        Tag(s) to exclude from the cloud.  May be either a single tag given as a string, or a
//        list of tags given as a list of strings.
//    showCount: bool (default:false)
//        Show the number of hits on each tag as a superscript next to the tag
//    align: str (default: "left")
//        Specifies the text alignment for the tag cloud.  Standard CSS values are available.
//    path: str (default: "")
//        Specifies root of subtree to look in.  Defaults to entire site.

var errors = [];

//**************
// Process Args
//**************

// order
var defaultOrder = "name";
var tagOrder = string.tolower($0 ?? $order ?? defaultOrder);
if (tagOrder != "name" && tagOrder != "count") {
    let errors ..= [ "ORDER must be either 'name' or 'count' (using default)" ];
    let tagOrder = defaultOrder;
}
// max
var defaultMax = 50;
var tagsLimit = $1 ?? $max ?? defaultMax;
if (tagsLimit is not num || tagsLimit < 0) {
    let errors ..= [ "MAX must be a number >= 0 (using default)" ];
    let tagsLimit = defaultMax;
}
// color
var defaultColor = [ [50,200,50], [50,100,50] ];
var color = $2 ?? $color ?? defaultColor;
if (color is list && #color == 3) let color = [ color,color ];
if (color is not list || #color != 2 ||
    color[0] is not list || #color[0] != 3 || color[1] is not list || #color[1] != 3 ||
    #list.select(color[0]..color[1], "$ is not num || $ < 0 || $ > 255"))
{
    let errors ..= [ "COLOR must be a list of 3 numbers, or list of two lists of three numbers;" ..
                   " each number must be in the range 0-255 (using default)" ];
    let color = defaultColor;
}
// size and sizeUnits (processing these together)
var defaultSize = [ 80,240 ];
var defaultUnits = "%";
var sizeMinMax = $3 ?? $size      ?? defaultSize ;
var sizeUnits  = $4 ?? $sizeUnits ?? defaultUnits;
if (sizeMinMax is num) let sizeMinMax = [ sizeMinMax, sizeMinMax ];
if (sizeMinMax is not list || sizeMinMax[0] is not num ||sizeMinMax[1] is not num) {
    let errors ..= [ "SIZE must be a number or list of two numbers (using default)" ];
    let sizeMinMax = defaultSize;
    let sizeUnits  = defaultUnits;
}
// exclude
var defaultExclude = [];
var tagsToExclude = $5 ?? $exclude ?? defaultExclude;
if (tagsToExclude is str) let tagsToExclude = [ tagsToExclude ];
if (tagsToExclude is not list) {
    let errors ..= [ "EXCLUDE must be a string or list of strings (using default)" ];
    let tagsToExclude = defaultExclude;
}
// showcount
var hitShow = $6 ?? $showCount ?? false;
// align
var align = $7 ?? $align ?? "left";
// path
var path = $8 ?? $path;
if (path is not str) {
    if (path is not nil) let errors ..= [ "PATH must be a string" ];
    let path = "";
}
let path = string.replace(path," ","_");

// bail out if errors, to give quick feedback
if (#errors)
    <div style="color:red">
        <strong> "SiteTagCloud encountered errors:" </strong>;
        <ul> foreach (var e in errors) <li> e </li>; </ul>;
    </div>;
else {
//****************************************
// Pre-process font size and color values
//****************************************
var minSize = sizeMinMax[0];
var sizeRange = sizeMinMax[1] - minSize;
var colorMin =   { r:color[0][0], g:color[0][1], b:color[0][2] };
var colorRange = { r:color[1][0]-colorMin.r, g:color[1][1]-colorMin.g, b:color[1][2]-colorMin.b };
//******************
// Process the tags
//******************
// convert list of excluded tags into a map (easier to check if tag is excluded)
let tagsToExclude = { (t): true foreach var t in tagsToExclude };
// compute map of tags based on site data and excluded tags
var tagMap = {};
foreach (var t in site.tags) {
    var tag = string.startswith(t.name, "define:") ? string.substr(t.name, 7) : t.name;
    if (tagsToExclude[tag]) continue;
    var count = #path ?    
                #[ 0 foreach var p in t.pages where string.startswith(p.path,path,true) ] :
                #t.pages;
    let tagMap ..= { (tag) : count + (tagMap[tag] ?? 0) };
}
// compute list of tags sorted by occurrence count
var tagListofMaps = [ { name: string.tocamelcase(t), count: tagMap[t] }
    foreach var t in map.keys(tagMap) where tagMap[t] > 0 ];
var tagsTotal = #tagListofMaps;
let tagListofMaps = list.sort(tagListofMaps, 'count', true);
if ((tagsLimit > 0) && !__request.args.alltags)
    let tagListofMaps = list.splice(tagListofMaps, tagsLimit);

//****************
// emit tag cloud
//****************
<div id="tagCloud">
    <div style=("text-align:" .. align)>
        if (#tagListofMaps) {
        // pre-calculate some shortcut variables
            var maxValue = tagListofMaps[0].count;
            var minValue = tagListofMaps[#tagListofMaps-1].count;
            var minLog   = num.log(minValue);
            var logRange = num.log(maxValue) - minLog;
        // Re-sort the list
            let tagListofMaps = list.sort(tagListofMaps, tagOrder, (tagOrder == "count"));
        // Output the cloud!
            foreach (var tm in tagListofMaps) {
                var tagURI = site.uri & "Special:Tags" & { tag:tm.name };
                var weight = ( num.log(tm.count) - minLog ) / logRange;
                var size = minSize + num.round(sizeRange * weight);
                var color = "color:rgb(" ..
                    num.min(colorMin.r + num.round(weight*colorRange.r),255) .. "," ..
                    num.min(colorMin.g + num.round(weight*colorRange.g),255) .. "," ..
                    num.min(colorMin.b + num.round(weight*colorRange.b),255) .. ");";
                <span style=("padding-right:5px; font-size:" .. size .. sizeUnits)>
                    <a href=(tagURI) style=(color)> tm.name </a>;
                    if (hitShow)
                        <sup style=(color.."font-size: x-small")> "(" .. tm.count .. ")" </sup>;
                    " ";
                </span>;
            }
        }
        else "(no tags)";
    </div>;
    if (!__request.args.alltags && (tagsLimit > 0) && (tagsTotal > tagsLimit)) {
        "Showing top " .. tagsLimit .. " tags. ";
        <a href=((page.uri & { alltags: "_" }).."#tagCloud")> "See all "..tagsTotal.." tags »" </a>;
    }
</div>;
}