share.js

/*jslint browser: true*/
window.jQuery(function ($) {
    'use strict';
    var url = 'https://www.missionbit.com/donate/',
        encodedURL = encodeURIComponent(url),
        title = encodeURIComponent('Free coding classes for SF public school students by @missionbit – '),
        buttons = $.makeArray($('.actions button').data('clicked', 0)),
        $percent = $('.progress .progress-bar'),
        $number = $('.progress .number');
    function clickFold(acc, el) {
        return acc + $(el).data('clicked');
    }
    function popup(url) {
        var w = 580,
            h = 300,
            left = (screen.width - w) / 2,
            top = (screen.height - h) / 2,
            opts = ['toolbar=0, location=0, directories=0, status=0, menubar=0, scrollbars=0, resizable=0, copyhistory=0',
                    ', width=', w,
                    ', height=', h,
                    ', top=', top,
                    ', left=', left].join('');
        window.open(url, '', opts);
    }
    $('.actions button').on('click', function buttonClick(event) {
        event.preventDefault();
        $(this).data('clicked', 1).blur();
        var clicks = buttons.reduce(clickFold, 0),
            percent = Math.min(100, Math.round(100 * (clicks / buttons.length)));
        $percent.width(percent + '%').attr('area-valuenow', percent);
        $number.text(percent + '%');
    });
    $('.actions button.facebook').on('click', function fbClick(event) {
        popup('https://www.facebook.com/share.php?u=' + encodedURL);
    });
    $('.actions button.twitter').on('click', function twitterClick(event) {
        popup(['https://twitter.com/share',
               '?text=', title,
               '&url=', encodedURL].join(''));
    });
    $('.actions button.play').on('click', function playClick(event) {
        window.location.href = url;
    });
});