browserHeight = window.innerHeight; // 600
midpoint = browserHeight / 2; // 300
quarterpoint = (midpoint / 2) + midpoint // 450
currentItem = 0;
padding = 5;
previousHeight = 1; 
prevItem = 0;
numPosts = 10;
thisHeight = new Array();
prevHeight = new Array();
prevFocus = 0;
heightText = '';
logger = 0;
postOrder = new Array();
scrollPosition = $('#window').scrollTop(); // 0

var http = false;
http = (navigator.appName == "Microsoft Internet Explorer") ? http = new ActiveXObject("Microsoft.XMLHTTP") : http = new XMLHttpRequest(); 

function log(action, object) {
   var url = "ajax.html?action=" + escape(action) + "&object=" + escape(object);
   http.open("GET", url, true);
   http.onreadystatechange=function() {
     //if(http.readyState == 4) { window.location=url; }
   }
   http.send(null);
}

function ajax(action, object) {
   var url = "ajax.html?action=" + escape(action) + "&object=" + escape(object);
   http.open("GET", url, true);
   http.onreadystatechange=function() {
     if(http.readyState == 4) {
        if (http.responseText == "Refresh") {
           window.location.reload();
        }
     }
   }
   http.send(null);
}

function animateScroll(where) {
   if ($('#c' + where).offset() != null) {
      $('#window').animate({
         scrollTop: $('#c' + where).offset().top
      }, 2000);
   }
   else {
      var url = "ajax.html?action=" + escape('get post ID from comment ID') + "&object=" + escape(where);
      http.open("GET", url, true);
      http.onreadystatechange=function() {
        if(http.readyState == 4) {
           window.location = 'index.html?post_id=' + http.responseText;
        }
      }
      http.send(null);
   }
}

function getHeights() {
   var total = 0;
   for (var i=0; i < numPosts; i++) {
      total = total + itemHeight(i);
      thisHeight[i] = itemHeight(i);
      prevHeight[i] = total - itemHeight(i);
   }
}

function itemHeight(div) {
   return $('#' + postOrder[div]).outerHeight(); // 100 + 5
}

function whereFocus(scroll) {
   var total = 0;
      for (var i=0; i < numPosts; i++) {
         if (prevHeight[i] < (scroll + browserHeight/4) && prevHeight[i+1] >= (scroll + browserHeight/4)) {
            prevItem = currentItem;
            focusCurrentItem(i);
         }
      }
}

function evalScroll() {
   newPosition = $('#window').scrollTop(); // 15
   prevNum = currentItem - 1;
   whereFocus(newPosition); 
}

function focusCurrentItem(num) {
   $('.post').removeClass('shadow');
   $('#' + postOrder[num]).addClass('shadow');
   if (currentItem != num) {
      log('focus', $('#' + postOrder[num]).attr('id') );
   }
   currentItem = num;
}

function postComment(post_id) {
   var commentText = $('#comment-text-' + post_id).val();
   var url = "ajax.html?action=postComment&post_id=" + post_id + "&text=" + escape(commentText);
   http.open("GET", url, true);
   http.onreadystatechange=function() {
     if(http.readyState == 4) {
        var newText = commentText.replace("\n\n", "<br><br>");
        newText = newText.replace("\n", "<br>");
        $('#comment-text-' + post_id).before( '<div class=comment-box id=c' + http.responseText + '><div style="float:right; width:100px; z-index:7; margin-right:-10px; margin-top:-10px"><object data="http://blog.pressbin.com/mugshot.svg?photo=mugshot/.jpg" type="image/svg+xml"/></div><h3></h3><br>' + newText + '</div>' );
        $('#comment-text-' + post_id).val('');
     }
   }
   http.send(null);   
}

placeholderID = new Array();
function placeholder(item) {
   if (placeholderID[item] != 1) {
      item.value = '';
      item.style.color = '#000';
      placeholderID[item] = 1;
   }
}

function checkEnter(e) {
 $('#q').keydown(function(e) {
   e = e || event;
   if(e.keyCode==13){
      window.location = 'index.html?q=' + escape($('#q').val());
   }
 });
}

function cooptSpacebar() {
 document.onkeydown=function(e){
   e = e || event;
   if(e.keyCode==32){
      if (currentItem < numPosts-1) { 
         currentItem++;
         focusCurrentItem(currentItem);
         $('#window').scrollTop(prevHeight[currentItem] - 100);
      }
      return false;
   }
   if(e.keyCode==33) {
      // Page up
      var h = $('#window').outerHeight();
      var currentScrollPosition = $('#window').scrollTop();
      var newScrollPosition = currentScrollPosition - h;
      $('#window').scrollTop(newScrollPosition);
      return false;
   }
   if(e.keyCode==34) {
      // Page down
      var h = $('#window').outerHeight();
      var currentScrollPosition = $('#window').scrollTop();
      var newScrollPosition = currentScrollPosition + h;
      $('#window').scrollTop(newScrollPosition);
      return false;
   }
   if(e.keyCode==38) {
      // Up arrow
      var currentScrollPosition = $('#window').scrollTop();
      var newScrollPosition = currentScrollPosition - 15;
      $('#window').scrollTop(newScrollPosition);
      return false;
   }
   if(e.keyCode==40) {
      // Down arrow
      var currentScrollPosition = $('#window').scrollTop();
      var newScrollPosition = currentScrollPosition + 15;
      $('#window').scrollTop(newScrollPosition);
      return false;
   }


 };
}

function releaseSpacebar() {
 document.onkeydown=function(e) {
   if(e.keyCode==33) {
      // Page up
      var h = $('#window').outerHeight();
      var currentScrollPosition = $('#window').scrollTop();
      var newScrollPosition = currentScrollPosition - h;
      $('#window').scrollTop(newScrollPosition);
      return false;
   }
   if(e.keyCode==34) {
      // Page down
      var h = $('#window').outerHeight();
      var currentScrollPosition = $('#window').scrollTop();
      var newScrollPosition = currentScrollPosition + h;
      $('#window').scrollTop(newScrollPosition);
      return false;
   }
 }
}

$(document).ready(function() {
  log('load');
  cooptSpacebar();
  $('.post').each(
     function(intIndex){
        postOrder[intIndex] = $(this).attr('id');
     }
  );
  $('textarea').each( function() {
     $(this).focus(releaseSpacebar );
     $(this).blur(cooptSpacebar );
  });

  $('#window').scroll(evalScroll);
  getHeights();
  log('focus', $('#' + postOrder[0]).attr('id') );
  $('#' + postOrder[0]).addClass('shadow');

  $('a').each(function() {
     $(this).bind('click', function() {
        log('click', $(this).attr('href'));
     });
  });

});

if (window.attachEvent) {
   window.attachEvent('unload', function() { log('unload'); }, true);
}
else {
   window.addEventListener('unload', function() { log('unload'); }, true);
}