// Touch me here :-)
var upH = 11; // Height of up-arrow
var upW = 11; // Width of up-arrow
var downH = 11; // Height of down-arrow
var downW = 11; // Width of down-arrow
var dragH = 25; // Height of scrollbar
var dragW = 16; // Width of scrollbar
var scrollH = 315; // Height of scrollbar
var speed = 10; // Scroll speed

// And now... go to the bottom of the page...

// Browser detection
var dom = document.getElementById ? true:false;
var nn4 = document.layers ? true:false;
var ie4 = document.all ? true:false;

var mouseY; // Mouse Y position onclick
var mouseX; // Mouse X position onclick

var clickUp = false; // If click on up-arrow
var clickDown = false; // If click on down-arrow
var clickDrag = false; // If click on scrollbar
var clickAbove = false; // If click above scrollbar
var clickBelow = false; // If click below scrollbar

var timer = setTimeout("",500); // Repeat variable
var upL; // Up-arrow X
var upT; // Up-arrow Y
var downL; // Down-arrow X
var downT; // Down-arrow Y
var dragL; // Scrollbar X
var dragT; // Scrollbar Y
var rulerL; // Ruler X
var rulerT; // Ruler Y
var contentT; // Content layer Y;
var contentH; // Content height
var contentClipH; // Content clip height
var scrollLength; // Number of pixels scrollbar should move
var startY; // Keeps track of offset between mouse and span

// Mousedown
function down(e)
{
  if((document.layers && e.which!=1) || (document.all && event.button!=1)) return true;
  // Enables the right mousebutton
  getMouse(e);
  startY = (mouseY - dragT);
  // If click on up-arrow
  if(mouseX >= upL && (mouseX <= (upL + upW)) && mouseY >= upT && (mouseY <= (upT + upH)))
  {
    clickUp = true;
    return scrollUp();
  }
  // Else if click on down-arrow
  else if(mouseX >= downL && (mouseX <= (downL + downW)) && mouseY >= downT && (mouseY <= (downT + downH)))
       {
         clickDown = true;
         return scrollDown();
       }
       // Else if click on scrollbar
       else if(mouseX >= dragL && (mouseX <= (dragL + dragW)) && mouseY >= dragT && (mouseY <= (dragT + dragH)))
        {
          clickDrag = true;
          return false;
        }
        else if(mouseX >= dragL && (mouseX <= (dragL + dragW)) && mouseY >= rulerT && (mouseY <= (rulerT + scrollH)))
        {
         // If click above drag
         if(mouseY < dragT)
         {
           clickAbove = true;
           clickUp = true;
           return scrollUp();
         }
         // Else click below drag
         else{
               clickBelow = true;
               clickDown = true;
               return scrollDown();
             }
        }
        // If no scrolling is to take place
        else{ return true;}
}

// Drag function
function move(e)
{
  if(clickDrag && contentH > contentClipH)
  {
    getMouse(e);
    dragT = (mouseY - startY);
    if(dragT < (rulerT)) dragT = rulerT;
    if(dragT > (rulerT + scrollH - dragH)) dragT = (rulerT + scrollH - dragH);

    contentT = ((dragT - rulerT)*(1/scrollLength));
    contentT = eval('-' + contentT);

    moveTo();

    // So ie-pc doesn't select gifs
    if(ie4) return false;
  }
}

function up()
{
  clearTimeout(timer);
  // Resetting variables
  clickUp = false;
  clickDown = false;
  clickDrag = false;
  clickAbove = false;
  clickBelow = false;
  return true;
}

// Reads content layer top
function getT()
{
  if(ie4)contentT = document.all.content.style.pixelTop;
  else if(nn4) contentT = document.contentClip.document.content.top;
  else if(dom) contentT = parseInt(document.getElementById("content").style.top);
}

// Reads mouse X and Y coordinates
function getMouse(e)
{
  if(ie4){
           mouseY = event.clientY + document.body.scrollTop;
		   mouseX = event.clientX + document.body.scrollLeft;
		   }
  else if(nn4 || dom)
       {
          mouseY = e.pageY;
          mouseX = e.pageX;
       }
}

// Moves the layer
function moveTo()
{
  if(ie4)
  {
     document.all.content.style.top = contentT;
     document.all.ruler.style.top = dragT;
     document.all.drag.style.top = dragT;
  }
  else if(nn4)
       {
         document.contentClip.document.content.top = contentT;
         document.ruler.top = dragT;
         document.drag.top = dragT;
       }
       else if(dom)
            {
              document.getElementById("content").style.top = contentT + "px";
              document.getElementById("drag").style.top = dragT + "px";
              document.getElementById("ruler").style.top = dragT + "px";
            }
}

// Scrolls up
function scrollUp()
{
  getT();
  if(clickAbove){
                  if(dragT <= (mouseY-(dragH/2))) return up();
                }

  if(clickUp){ if(contentT < 0)
               {
                 dragT = dragT - (speed*scrollLength);
                 if(dragT < (rulerT))dragT = rulerT;

                 contentT = contentT + speed;
                 if(contentT > 0) contentT = 0;

                 moveTo();
                 timer = setTimeout("scrollUp()",25);
               }
             }
 return false;
}

// Scrolls down
function scrollDown()
{
  getT();
  if(clickBelow)
  {
    if(dragT >= (mouseY-(dragH/2))) return up();
  }

  if(clickDown)
  {
    if(contentT > -(contentH - contentClipH))
    {
      dragT = dragT + (speed*scrollLength);
      if(dragT > (rulerT + scrollH - dragH)) dragT = (rulerT + scrollH - dragH);

      contentT = contentT - speed;
      if(contentT < -(contentH - contentClipH)) contentT = -(contentH - contentClipH);

      moveTo();
      timer = setTimeout("scrollDown()",25);
    }
  }
  return false;
}

// reloads page to position the layers again
function reloadPage()
{
  location.reload();
}

// Preload
function eventLoader()
{
  if(ie4)
  {
    // Up-arrow X and Y variables
    upL = document.all.up.style.pixelLeft;
	upT = document.all.up.style.pixelTop;
    // Down-arrow X and Y variables
    downL = document.all.down.style.pixelLeft;
    downT = document.all.down.style.pixelTop;
    // Scrollbar X and Y variables
    dragL = document.all.drag.style.pixelLeft;
    dragT = document.all.drag.style.pixelTop;
    // Ruler Y variable
    rulerT = document.all.ruler.style.pixelTop;
    // Height of content layer and clip layer
    contentH = parseInt(document.all.content.scrollHeight);
    contentClipH = parseInt(document.all.contentClip.style.height);
  }
  else if(nn4)
       {
         // Up-arrow X and Y variables
         upL = document.up.left;
         upT = document.up.top;
         // Down-arrow X and Y variables
         downL = document.down.left;
         downT = document.down.top;
         // Scrollbar X and Y variables
         dragL = document.drag.left;
         dragT = document.drag.top;
         // Ruler Y variable
         rulerT = document.ruler.top;
         // Height of content layer and clip layer
         contentH = document.contentClip.document.content.clip.bottom;
         contentClipH = document.contentClip.clip.bottom;
       }
       else if(dom)
            {
               // Up-arrow X and Y variables
               upL = parseInt(document.getElementById("up").style.left);
               upT = parseInt(document.getElementById("up").style.top);
               // Down-arrow X and Y variables
               downL = parseInt(document.getElementById("down").style.left);
               downT = parseInt(document.getElementById("down").style.top);
               // Scrollbar X and Y variables
               dragL = parseInt(document.getElementById("drag").style.left);
               dragT = parseInt(document.getElementById("drag").style.top);
               // Ruler Y variable
               rulerT = parseInt(document.getElementById("ruler").style.top);
               // Height of content layer and clip layer
               contentH = parseInt(document.getElementById("content").offsetHeight);
               contentClipH = parseInt(document.getElementById("contentClip").offsetHeight);
               document.getElementById("content").style.top = 0 + "px";
            }
        // Number of pixels scrollbar should move
        scrollLength = ((scrollH-dragH)/(contentH-contentClipH));
        // Initializes event capturing
        if(nn4)
        {
          document.captureEvents(Event.MOUSEDOWN | Event.MOUSEMOVE | Event.MOUSEUP);
          window.onresize = reloadPage;
        }
        document.onmousedown = down;
        document.onmousemove = move;
        document.onmouseup = up;
}
onload=eventLoader