User:Proteins/followrandomlinkonpage.js

//

// Travel to a random page linked in the article (a so-called "aleation" or an "aleatory fugue")
//
// To use this script, add "importScript('User:Proteins/followrandomlinkonpage.js');" to your monobook.js subpage
// under your user page, as you can see at User:Proteins/monobook.js
function followRandomLinkOnPage() {
var alert_string = "";
var top_node;
var hyperlinks;
var num_hyperlinks = 0;
var random_double = 0.5;
var random_hyperlink_index = 0;
var random_link;
var random_link_href = "";
var random_link_title = "";
var num_iterations = 0;
var max_num_iterations = 100;
var bad_link = true;
// Get the bodyContent node
top_node = document.getElementById('bodyContent');
if (!top_node) {
window.alert("There is no bodyContent node in this article.");
return;
}
// Get a list of the hyperlinks
hyperlinks = top_node.getElementsByTagName("A");
if (!hyperlinks) {
window.alert("There are no hyperlinks in this article.");
return;
}
num_hyperlinks = hyperlinks.length;
if (num_hyperlinks < 1) {
window.alert("There are no hyperlinks in this article.");
return;
}
// Choose a random hyperlink
bad_link = true;
num_iterations = 0;
random_link = null;
random_link_href = "";
random_link_title = "";
while ((num_iterations
num_iterations++;
random_double = num_hyperlinks * Math.random();
random_hyperlink_index = Math.floor(random_double);
if ((random_hyperlink_index < 0) || (random_hyperlink_index >= num_hyperlinks)) { continue; }
random_link = hyperlinks[random_hyperlink_index];
random_link_href = random_link.href;
random_link_title = random_link.title;
if ((!random_link) || (!random_link_title) || (!random_link_title)) {
// Check that all three exist
continue;
} else if (random_link.className) {
// Don't follow external links
continue;
} else if (random_link_title.match(/\(page does not exist\)$/ig)) {
// Don't follow red links
continue;
} else if (random_link_title.match(/^Image:/ig)) {
// Don't follow Image links
continue;
} else if (random_link_title.match(/^Category:/ig)) {
// Don't follow Category links
continue;
} else if (random_link_title.match(/^Special:/ig)) {
// Don't follow links to Special pages
continue;
} else if ((random_link_title.match(/^Edit\ssection:/i)) && (random_link_href.match(/action\=edit/i))) {
// Don't follow edit links
continue;
}
if (wgNamespaceNumber == 0) { // special behavior for Main article space
if (random_link.id) { continue; }
if (random_link_href.match(/Talk:/ig)) { continue; }
if (random_link_href.match(/Wikipedia:/ig)) { continue; }
if (random_link_href.match(/Wikipedia talk:/ig)) { continue; }
if (random_link_href.match(/Portal:/ig)) { continue; }
if (random_link_href.match(/Portal talk:/ig)) { continue; }
if (random_link_href.match(/User:/ig)) { continue; }
if (random_link_href.match(/User talk:/ig)) { continue; }
if (random_link_href.match(/Help:/ig)) { continue; }
if (random_link_href.match(/Help talk:/ig)) { continue; }
if (random_link_href.match(/Template:/ig)) { continue; }
if (random_link_href.match(/Template talk:/ig)) { continue; }
if (random_link_href.match(/Category:/ig)) { continue; }
if (random_link_href.match(/Category talk:/ig)) { continue; }
if (random_link_href.match(/File:/ig)) { continue; }
if (random_link_href.match(/File talk:/ig)) { continue; }
if (random_link_href.match(/MediaWiki:/ig)) { continue; }
if (random_link_href.match(/MediaWiki talk:/ig)) { continue; }
} // closes check for Main article space
bad_link = false;
} // closes loop generating a random hyperlink
// Follow the randomly chosen link to the new location
if (bad_link == false) {
alert_string = "Follow link to the page \"" + random_link_title + "\"\?\n";
if (window.confirm(alert_string) == true) {
window.open(random_link_href);
}
} else {
alert_string = "Unable to find a suitable random link in " + max_num_iterations + " attempts.\n";
window.alert(alert_string);
}
} // closes function followRandomLinkOnPage()
addOnloadHook(function () {
mw.util.addPortletLink('p-navigation', 'javascript:followRandomLinkOnPage()', 'Follow a lucky link!', 'ca-lucky', 'Follow a randomly chosen link on this page', '@', '');
});
//