// _mac : true = macintosh, false = other os
_mac   = navigator.userAgent.toLowerCase().indexOf('mac')!=-1;
// _ie512 : true = MSIE 5.12(mac), false = others
_ie512 = navigator.userAgent.toLowerCase().indexOf('msie 5.12')!=-1;
// _kon : true = konqueror, false = others
_kon    = navigator.userAgent.toLowerCase().indexOf('konqueror')!=-1;
// _safari : true = safari, false = others
_safari = navigator.userAgent.toLowerCase().indexOf('safari')!=-1;
// _dom : kind of DOM.

// 1:IE4
// 2:IE5+
// 3:N4
// 4:N6+ F1+ O6+ S1+
// 0:others N5 O5-
_dom = document.all?(document.getElementById?2:1):(document.getElementById?4:(document.layers?3:0));

function getWinYOffset(){

  //if(_dom == 4){
//    return window.scrollY;
//  }
  
  if(_dom == 2 || _dom == 1){
    if(navigator.appName == "Microsoft Internet Explorer" && document.compatMode == "CSS1Compat") {
       //return document.body.parentNode.scrollTop;
   return document.documentElement.scrollTop;
    } else {
       return document.body.scrollTop;
    }
  }
  
  if(_dom == 3 || _dom == 4){
    return window.pageYOffset; //F1+ S1+ O9+確認していない
  }
  return 0;
}

function getDivTop(div){
  if(_dom == 4 || _dom == 2){
    return div.offsetTop;

  }
  if(_dom == 1){
    return div.style.pixelTop;
  }
  if(_dom == 3){
    return div.top;
  }
  return 0;
}

var move2pos = 0;
var go2pos = 0;

function scrollerDown(pos) {
  var IE  = navigator.appName.indexOf("Microsoft Internet Explorer",0) != -1;
  if( IE ){
    obj1 = document.all('__pos_offset');
    obj2 = document.all(pos);
    if(obj1 != null){
      position = getDivTop(obj2) + getDivTop(obj1);
    }else{
      position = getDivTop(obj2);
    }
  } else {
    obj = document.getElementById(pos);
    position = getDivTop(obj);
  }
  movePositionDown(pos);
}

function movePositionDown(pos) {
  if(go2pos == 0){
    move2pos = position;
  }
  move2pos = Math.floor(move2pos * 0.8);
  go2pos = position - move2pos;
  if( go2pos < position ){
    window.scrollTo(0,go2pos);
    setTimeout("scrollerDown('"+pos+"')",30);
  } else {
    window.scrollTo(0,position);
    //変数初期化
    move2pos = 0;
    go2pos = 0;
  }
}

function scrollerUp() {

  position = getWinYOffset();
  //alert(window.pageYOffset);
  movePositionUp();
  
}

function movePositionUp() {

  position = Math.floor(position*0.8);
  if( position > 0.1 ){
    window.scrollTo(0,position)
    setTimeout("scrollerUp()",12);
  } else {
    window.scrollTo(0,0);
  }
  
}