if (typeof PDoc === "undefined") window.PDoc = {};

// Poor-man's history manager. Polls for changes to the hash.
(function() {  
  var PREVIOUS_HASH = null;
  
  document.observe("dom:loaded", function() {    
    var hash = window.location.hash;
    if (hash && hash !== PREVIOUS_HASH) {
      document.fire("hash:changed",
       { previous: PREVIOUS_HASH, current: hash });        
      PREVIOUS_HASH = hash;      
    }
    
    window.setTimeout(arguments.callee, 100);  
  });  
})();

// Place a "frame" around the element described by the hash.
// Update the frame when the hash changes.
PDoc.highlightSelected = function() {
  if (!window.location.hash) return;  
  element = $(window.location.hash.substr(1));
  if (element) PDoc.highlight(element.up('li, div'));
};

document.observe("hash:changed", PDoc.highlightSelected);

PDoc.highlight = function(element) {
  var self = arguments.callee;
  if (!self.frame) {
    self.frame = new Element('div', { 'class': 'highlighter' });
    document.body.appendChild(self.frame);
  }
  
  var frame = self.frame;
  
  element.getOffsetParent().appendChild(frame);
  
  var offset = element.positionedOffset();
  var w = parseFloat(element.getStyle('width')),
      h = parseFloat(element.getStyle('height'));
      
  frame.setStyle({
    position: 'absolute',
    top: (offset.top - 5) + 'px',
    left: (offset.left - 5) + 'px',
    width:  (w + 5) + 'px',
    height: (h + 10) + 'px'
  });
  
  // Defer this call because Safari hasn't yet scrolled the viewport.
  (function() {
    var frameOffset = frame.viewportOffset(frame);
    if (frameOffset.top < 0) {
      window.scrollBy(0, frameOffset.top - 10);
    }    
  }).defer();
  
};

// Live API search.
var Filterer = Class.create({
  initialize: function(element, options) {
    this.element = $(element);
    this.options = Object.extend({
      interval: 0.1,
      resultsElement: '.search-results'
    }, options || {});
    
    this.element.writeAttribute("autocomplete", "off");    
    this.element.up('form').observe("submit", Event.stop);
    
    // // The Safari-only "search" input type is prettier
    // if (Prototype.Browser.WebKit)
    //   this.element.type = "search";
    
    this.menu = this.options.menu;
    this.links = this.menu.select('a');
    
    this.resultsElement = this.options.resultsElement;
    this.resultsElement.setStyle({
      overflowX: 'hidden'
    });
    
    this.events = {
      filter:   this.filter.bind(this),
      keydown: this.keydown.bind(this)
    };
    
    this.menu.setStyle({ opacity: 0.9 });
    this.addObservers();
    
    this.element.value = '';
  },
  
  addObservers: function() {
    this.element.observe('keyup', this.events.filter);
  },
  
  filter: function(event) {
    if (this._timer) window.clearTimeout(this._timer);
    
    // Clear the text box on ESC
    if (event.keyCode && event.keyCode === Event.KEY_ESC) {
      this.element.value = '';
    }
    
    if ([Event.KEY_UP, Event.KEY_DOWN, Event.KEY_RETURN].include(event.keyCode))
      return;
    
    var value = $F(this.element).strip().toLowerCase();    
    if (value === "") {
      this.onEmpty();
      return;
    }
    
    var urls  = this.findURLs(value);  
    this.buildResults(urls);
  },
  
  keydown: function(event) {
    if (![Event.KEY_UP, Event.KEY_DOWN, Event.KEY_RETURN].include(event.keyCode))
      return;
      
    // ignore if any modifier keys are present
    if (event.shiftKey || event.ctrlKey || event.altKey || event.metaKey)
      return;
      
    event.stop();
    
    var highlighted = this.resultsElement.down('.highlighted');
    if (event.keyCode === Event.KEY_RETURN) {
      // Follow the highlighted item.
      if (!highlighted) return;
      window.location.href = highlighted.down('a').href;
    } else {
      var direction = (Event.KEY_DOWN === event.keyCode) ? 1 : -1;
      highlighted = this.moveHighlight(direction);
    }
    
    
    if ([Event.KEY_UP, Event.KEY_DOWN].include(event.keyCode) &&
     !Prototype.Browser.WebKit) {    
      // If up/down key is held down, list should keep scrolling.
      // Safari does this automatically because it fires the keydown
      // event over and over.
      this._timer = window.setTimeout(this.scrollList.bind(this, direction), 1000);
    }
  },
  
  moveHighlight: function(direction) {
    var highlighted = this.resultsElement.down('.highlighted');
    // move the focus
    if (!highlighted) {
      // if there is none, highlight the first result
      var highlighted = this.resultsElement.down('li').addClassName('highlighted');
    } else {
      var method = (direction === 1) ? 'next' : 'previous';
      highlighted.removeClassName('highlighted');
      var adjacent = highlighted[method]('li');
      if (!adjacent) {
        adjacent = method == 'next' ? this.resultsElement.down('li') :
         this.resultsElement.down('li:last-of-type');
      }
      adjacent.addClassName('highlighted');
      highlighted = adjacent;
    }

    // Adjust the scroll offset of the container so that the highlighted
    // item is always in view.
    var distanceToBottom = highlighted.offsetTop + highlighted.offsetHeight;
    if (distanceToBottom > this.resultsElement.offsetHeight + this.resultsElement.scrollTop) {
      // item is too low
      this.resultsElement.scrollTop = distanceToBottom - this.resultsElement.offsetHeight;
    } else if (highlighted.offsetTop < this.resultsElement.scrollTop) {
      // item is too high
      this.resultsElement.scrollTop = highlighted.offsetTop;
    }
    
    return highlighted;
  },
  
  scrollList: function(direction) {
    this.moveHighlight(direction);
    this._timer = window.setTimeout(this.scrollList.bind(this, direction), 100);
  },
  
  buildResults: function(urls) {
    this.resultsElement.update();
    var ul = this.resultsElement;
    urls.each( function(url) {
      var a  = new Element('a', {
        'class': url.type.gsub(/\s/, '_'),
        href:    PDoc.pathPrefix + url.path
      }).update(url.name);
      var li = new Element('li', { 'class': 'menu-item' });
      li.appendChild(a);
      ul.appendChild(li);
    });    
    this.showResults();
  },
    
  
  findURLs: function(str) {
    var results = [];
    for (var i in PDoc.elements) {
      if (i.toLowerCase().include(str)) results.push(PDoc.elements[i]);
    }
    return results;
  },
  
  onEmpty: function() {
    this.hideResults();
  },
  
  showResults: function() {
    this.resultsElement.show();
    document.stopObserving("keydown", this.events.keydown);
    document.observe("keydown", this.events.keydown);
  },
  
  hideResults: function() {
    this.resultsElement.hide();
    document.stopObserving("keydown", this.events.keydown);
  }  
});

document.observe('dom:loaded', function() {
  new Filterer($('search'), {
    menu: $('api_menu'), 
    resultsElement: $('search_results')
  });
});


Event.observe(window, 'load', function() {
  var menu = $('menu');
  var OFFSET = menu.viewportOffset().top;
  
  Event.observe(window, 'scroll', function() {
    var sOffset = document.viewport.getScrollOffsets();
    if (sOffset.top > OFFSET) {
      menu.addClassName('fixed');
    } else menu.removeClassName('fixed');
  });
});

(function() {
  function menuButtonMouseOver(event) {
    var menuButton = $('api_menu_button');
    var target = event.element();
    if (target === menuButton || target.descendantOf(menuButton)) {
      $('api_menu').show();
    }
  }
  
  function menuButtonMouseOut(event) {
    var menuButton = $('api_menu_button');
    var menu = $('api_menu');
    var target = event.element(), related = event.relatedTarget || event.toElement;
    
    if (related && (related === menu || related.descendantOf(menu))) return;
    menu.hide();
  }
  
  function menuMouseOut(event) {
    var menu = $('api_menu'), related = event.relatedTarget || event.toElement;
    if (related && !related.descendantOf(menu)) {
      arguments.callee.timer = Element.hide.delay(0.5, menu);
    } else {
      window.clearTimeout(arguments.callee.timer);
    }
  }
  
  function menuItemMouseOver(event) {
    var element = event.element();    
    if (element.tagName.toLowerCase() === 'a') {
      element.addClassName('highlighted');
    }
  }
  
  function menuItemMouseOut(event) {
    var element = event.element();    
    if (element.tagName.toLowerCase() === 'a') {
      element.removeClassName('highlighted');
    }
  }
  
  var MENU_ITEMS;
  
  document.observe('dom:loaded', function() {
    MENU_ITEMS = $$('.api-box .menu-item a');
    
    $('api_menu_button').observe('mouseenter', menuButtonMouseOver);
    $('api_menu_button').observe('mouseleave', menuButtonMouseOut );
    
    $('api_menu').observe('mouseleave', menuMouseOut);
    
    if (Prototype.Browser.IE) {
      $('api_menu').observe('mouseover', menuItemMouseOver);
      $('api_menu').observe('mouseout',  menuItemMouseOut);
    }
  });
})();