/* Pushup
 * Copyright (c) 2009 Nick Stakenburg (www.nickstakenburg.com)
 *
 * License: MIT-style license.
 * Website: http://www.pushuptheweb.com
 *
 */

var Pushup = {
  Version: '1.0.3',
  options: {
    appearDelay: .5,
    fadeDelay: 30,
    images: '../images/pushup/',
    message: 'Your browser appears to be out of date. In order to have the best possible online experience while visiting our site. Click here to update your browser to the newest version.',
    reminder: {
      hours: 0,
      message: ''
    },
    skip: true
  },
  updateLinks: {
    IE: 'http://www.microsoft.com/windows/downloads/ie/',
    Firefox: 'http://www.getfirefox.com',
    Safari: 'http://www.apple.com/safari/download/',
    Opera: 'http://www.opera.com/download/'
  },
  Browser: {
    IE: !!(window.attachEvent &&
      navigator.userAgent.indexOf('Opera') === -1),
    Firefox: navigator.userAgent.indexOf('Firefox') > -1,
    Safari: navigator.userAgent.indexOf('AppleWebKit/') > -1 &&
      /Apple/.test(navigator.vendor),
    Opera: navigator.userAgent.indexOf('Opera') > -1
  }
};

Pushup.conditions = {
  IE: (function(agent) {
    var version = /MSIE ([\d.]+)/.exec(agent);
    return version && parseFloat(version[1]) < 7;
  })(navigator.userAgent),
  Firefox: Pushup.Browser.Firefox &&
    parseFloat(navigator.userAgent.match(/Firefox[\/\s](\d+)/)[1]) < 3,
  Safari: Pushup.Browser.Safari &&
    parseFloat(navigator.userAgent.match(/AppleWebKit\/(\d+)/)[1]) < 500,
  Opera: Pushup.Browser.Opera && (!window.opera.version ||
    parseFloat(window.opera.version()) < 9.5)
};

(function() {
// find current browser and check if it needs an update
for (var browser in Pushup.Browser)
  if (Pushup.Browser[browser]) Pushup._browserUsed = browser;
Pushup._updateBrowser = Pushup.conditions[Pushup._browserUsed] &&
  Pushup._browserUsed;

// stop if no update is required and we want to skip build
if (!Pushup._updateBrowser && Pushup.options.skip) return;

function Extend(destination, source) {
  for (var property in source)
    destination[property] = source[property];
  return destination;
}

Extend(Pushup, {
  start: function() {
    // get the image directory
    if (/^(https?:\/\/|\/)/.test(this.options.images))
      this.images = this.options.images;
    else {
      var srcMatch = /pushup(?:-[\w\d.]+)?\.js(.*)/,
       scripts = document.getElementsByTagName('script');
      for (var i = 0, l = scripts.length; i < l; i++) {
        var s = scripts[i];
        if (s.src && s.src.match(srcMatch))
          this.images = s.src.replace(srcMatch, '') + this.options.images;
      }
    }
    if (Pushup._updateBrowser) this.show();
  },

  build: function() {
    this.pushup = document.createElement('div');
    Opacity.set(this.pushup, 0);
    this.pushup.id = 'pushup';

    this.messageLink = this.pushup.appendChild(document.createElement('a'));
    this.messageLink.className = 'pushup_messageLink';
    this.messageLink.target = '_blank';

    this.messageLink.appendChild(this.icon = document.createElement('div'));
    this.icon.className = 'pushup_icon';

    this.messageLink.appendChild(this.message = document.createElement('span'));
    this.message.className = 'pushup_message';
    this.message.innerHTML = this.options.message;

    // reminder message if cookies are enabled
    var hours = this.options.reminder.hours;
    if (hours && Pushup.cookiesEnabled) {
      this.pushup.appendChild(this.reminder = document.createElement('a'));
      this.reminder.href = '#';
      this.reminder.className = 'pushup_reminder';
      this.pushup.className = 'withReminder';
      var H = hours + ' hour' + (hours > 1 ? 's' : ''),
       message = this.options.reminder.message.replace('#{hours}', H);
      this.reminder.innerHTML = message;
    }

    // Older Opera doesn't handle float correctly
    if (Pushup.Browser.Opera &&
       (!window.opera.version || parseFloat(window.opera.version()) < 9.25)) {
      this.messageLink.style.cssFloat = 'none';
      this.reminder.style.cssFloat = 'none';
    }

    Pushup.setBrowser(Pushup._updateBrowser);
    document.body.appendChild(this.pushup);
    Pushup.addEvents();
  },

  addEvents: function() {
    if (this.reminder) {
      Event.add(this.reminder, 'click', function(event) {
        Event.stop(event);
        Pushup.setReminder(Pushup.options.reminder.hours);
        Pushup.fade();
      });
    }
    Event.add(this.pushup, 'mouseover', Pushup.clearFade);
    Event.add(this.pushup, 'mouseout', function() {
      Pushup.fade({ delay: Pushup.options.fadeDelay })
    });
  },

  setBrowser: function(browser) {
    browser = browser || 'IE';
    setPngBackground(this.icon, this.images + browser.toLowerCase() + '.png');
    this.messageLink.href = this.updateLinks[browser];
  },

  show: function() {
    // default to IE if no browser was detected
    var browser = typeof arguments[0] == 'string' ?
      arguments[0] : Pushup._browserUsed || 'IE',
     options = arguments[browser ? 1 : 0] || {};

    if (options.resetReminder) Pushup.resetReminder();

    // show if not blocked by cookie
    if (!options.ignoreReminder && Pushup.cookiesEnabled &&
      Cookie.get('_pushupBlocked')) return;

    if (!Pushup.pushup) Pushup.build();
    Opacity.set(Pushup.pushup, 0);
    Pushup.pushup.style.display = 'block';
    if (browser) Pushup.setBrowser(browser);
    this.appear({ fadeAfter: true, delay: Pushup.options.appearDelay });
  },

  appear: function(delay) {
    Pushup.clearFade();
    var options = arguments[0] || {};
    return window.setTimeout(function() {
      Appear(Pushup.pushup, { afterFinish: function() {
        if (options.fadeAfter)
          Pushup.fade({ delay: Pushup.options.fadeDelay });
      }});
    }, (options.delay || 0.01) * 1000);
  },

  clearFade: function() {
    if (Pushup._fadeTimer) {
      window.clearTimeout(Pushup._fadeTimer);
      Pushup._fadeTimer = null;
    }
  },

  fade: function() {
    var options = arguments[0] || {};
    Pushup._fadeTimer = window.setTimeout(function() {
      Fade(Pushup.pushup);
    }, (options.delay || 0.01) * 1000);
  },

  setReminder: function(hours) {
    Cookie.set('_pushupBlocked', 'blocked', { duration: 1 / 24 * hours })
  },

  resetReminder: function() { Cookie.remove('_pushupBlocked') }
});

// Opacity adapted from the Prototype JavaScript framework
// http://www.prototypejs.org
var Opacity = {
  set: function(element, value) {
    element.style.opacity = (value == 1 || value === '') ? '' :
      (value < 0.00001) ? 0 : value;
  },

  get:  function(element) {
    var opacity = element.style.opacity;
    return opacity ? parseFloat(opacity) : 1.0;
  }
};

if (Pushup.Browser.IE) {
  Opacity.get = function(element) {
    var opacity = element.style.opacity;
    if (!opacity && element.currentStyle) opacity = element.currentStyle[opacity];

    if (opacity = (element.style.filter || '').match(/alpha\(opacity=(.*)\)/))
      if (opacity[1]) return parseFloat(opacity[1]) / 100;
    return 1.0;
  };

  Opacity.set = function(element, value) {
    function stripAlpha(filter) {
      return filter.replace(/alpha\([^\)]*\)/gi,'')
    }
    var currentStyle = element.currentStyle;
    if ((currentStyle && !currentStyle.hasLayout) ||
      (!currentStyle && element.style.zoom == 'normal'))
        element.style.zoom = 1;
    var filter = element.style.filter,
     style = element.style;
    if (value == 1 || value === '') (filter = stripAlpha(filter)) ?
      style.filter = filter : style.filter = '';
    else style.filter = stripAlpha(filter) +
      'alpha(opacity=' + (value * 100) + ')';
  };
}

function Appear(element) {
  var current = Opacity.get(element),
   options = arguments[1] || {};
  if (element.style.display != 'block')
    element.style.display = 'block';
  if (current < 1) {
    setTimeout(function() {
      Opacity.set(element, current += 0.05);
      Appear(element, options);
    }, 0.01);
  }
  else {
    if (Pushup.Browser.IE && element.style.filter)
      element.style.removeAttribute('filter');
    if (options.afterFinish) options.afterFinish.call();
  }
}

function Fade(element) {
  var current = Opacity.get(element),
   options = arguments[1] || {};
  if (current > 0) {
    setTimeout(function() {
      Opacity.set(element, current -= 0.05);
      Fade(element, options);
    }, 0.01);
  }
  else {
    element.style.display = 'none';
    if (options.afterFinish) options.afterFinish.call();
  }
}

function setPngBackground(element, url) {
  var options = Extend({
    align: 'top left',
    repeat: 'no-repeat',
    sizingMethod: 'crop',
    backgroundColor: ''
  }, arguments[2] || {});

  Extend(element.style, arguments.callee.IEBelow7 ? {
    filter: 'progid:DXImageTransform.Microsoft.AlphaImageLoader(src=\'' +
      url + '\'\', sizingMethod=\'' + options.sizingMethod + '\')'
  } : {
    background: options.backgroundColor + ' url(' + url + ') ' +
      options.align + ' ' + options.repeat
  });
}
setPngBackground.IEBelow7 = Pushup.Browser.IE &&
  parseFloat(/MSIE ([\d.]+)/.exec(navigator.userAgent)[1]) < 7;

// Based on the work of Peter-Paul Koch - http://www.quirksmode.org
var Cookie = {
  set: function(name, value) {
    var expires = '', options = arguments[2] || {};
    if (options.duration) {
      var date = new Date();
      date.setTime(date.getTime() + options.duration * 1000 * 60 * 60 * 24);
      value += '; expires=' + date.toGMTString();
    }
    document.cookie = name + "=" + value + expires + "; path=/";
  },

  remove: function(name) { this.set(name, '', -1) },

  get: function(name) {
    var cookies = document.cookie.split(';'), nameEQ = name + "=";
    for (var i = 0, l = cookies.length; i < l; i++) {
      var c = cookies[i];
      while (c.charAt(0) == ' ')
        c = c.substring(1,c.length);
      if (c.indexOf(nameEQ) == 0)
        return c.substring(nameEQ.length, c.length);
    }
    return null;
  }
};

// check if cookies are enabled
Pushup.cookiesEnabled = (function(test) {
  if (Cookie.get(test)) return true;
  Cookie.set(test, 'test', { duration: 15 });
  return Cookie.get(test);
})('_pushupCookiesEnabled');

var Event = {
  add: function(obj, type, fn) {
    if (obj.attachEvent) {
      obj['e' + type + fn] = fn;
      obj[type + fn] = function(){ obj['e' + type +fn](window.event) };
      obj.attachEvent('on' + type, obj[type + fn]);
    }
    else obj.addEventListener(type, fn, false);
  },

  stop: function(event) {
    if (Pushup.Browser.IE) {
      event.cancelBubble = true;
      event.returnValue = false;
    }
    else {
      event.preventDefault();
      event.stopPropagation();
    }
  }
};

Event.add(window, 'load', function() { Pushup.start() });
})();