var DDSPEED = 10;


var DDTIMER = 15;





// main function to handle the mouse events //


function ddMenu(id,d){


  var h = document.getElementById(id + '-ddheader');


  var c = document.getElementById(id + '-ddcontent');


  clearInterval(c.timer);


  if(d == 1){


    clearTimeout(h.timer);


    if(c.maxh && c.maxh <= c.offsetHeight){return}


    else if(!c.maxh){


      c.style.display = 'block';


      c.style.height = 'auto';


      c.maxh = c.offsetHeight;


      c.style.height = '0px';


    }


    c.timer = setInterval(function(){ddSlide(c,1)},DDTIMER);


  }else{


    h.timer = setTimeout(function(){ddCollapse(c)},50);


  }


}





// collapse the menu //


function ddCollapse(c){


  c.timer = setInterval(function(){ddSlide(c,-1)},DDTIMER);


}





// cancel the collapse if a user rolls over the dropdown //


function cancelHide(id){


  var h = document.getElementById(id + '-ddheader');


  var c = document.getElementById(id + '-ddcontent');


  clearTimeout(h.timer);


  clearInterval(c.timer);


  if(c.offsetHeight < c.maxh){


    c.timer = setInterval(function(){ddSlide(c,1)},DDTIMER);


  }


}





// incrementally expand/contract the dropdown and change the opacity //


function ddSlide(c,d){


  var currh = c.offsetHeight;


  var dist;


  if(d == 1){


    dist = (Math.round((c.maxh - currh) / DDSPEED));


  }else{


    dist = (Math.round(currh / DDSPEED));


  }


  if(dist <= 1 && d == 1){


    dist = 1;


  }


  c.style.height = currh + (dist * d) + 'px';


  c.style.opacity = currh / c.maxh;


  c.style.filter = 'alpha(opacity=' + (currh * 100 / c.maxh) + ')';


  if((currh < 2 && d != 1) || (currh > (c.maxh - 2) && d == 1)){


    clearInterval(c.timer);


  }


}