var casper = require('casper').create({
    verbose: true
});

// If we don't set a limit, it could go on forever
var upTo = ~~casper.cli.get(0) || 10; // max 10 links

// Fetch all <a> elements from the page and return
// the ones which contains a href starting with 'http://'
var searchLinks = function searchLinks() {
    var filter = Array.prototype.filter;
    var map = Array.prototype.map;
    return map.call(filter.call(document.querySelectorAll("a"), function(a) {
        return /^http:\/\/.*/i.test(a.getAttribute("href"));
    }), function(a) {
        return a.getAttribute("href");
    });
};

// The base links array
var links = [
    'http://google.com/',
    'http://yahoo.com/',
    'http://bing.com/'
];

// Just opens the page and prints the title
var start = function start(link) {
    this.start(link, function() {
        this.echo("Page title: " + (this.getTitle()));
    });
};

// Get the links, and add them to the links array
// (It could be done all in one step, but it is intentionally splitted)
var addLinks = function addLinks(link) {
    this.then(function() {
        var found = this.evaluate(searchLinks);
        this.echo("" + found.length + " links found on " + link);
        links = links.concat(found);
    });
};

casper.start();

casper.then(function() {
    this.echo('Starting');
});

var currentLink = 0;

// As long as it has a next link, and is under the maximum limit, will keep running
var check = function check() {
    if (links[currentLink] && currentLink < upTo) {
        this.echo("--- Link " + currentLink + " ---");
        start.call(this, links[currentLink]);
        addLinks.call(this, links[currentLink]);
        currentLink++;
        this.run(check);
    } else {
        this.echo('All done.');
        this.exit();
    }
};

casper.run(check);