// JavaScript Document


function dhCombobox(){

var dh = this;
this.callbackName = null;
this.datasource = [];
this.trgetObj = null;
this.w = 250;
this.h = 150;

var tempArr = [];
var totalL = 0;
var startL = 0;
var endL = 0;

//匹配用户输入字符结果
Array.prototype.contains = function(o){
    var tc = [];
    for(var i=0,l=this.length;i<l;i++){
     if(-1 != this[i].toString().indexOf(o)){
      tc.push(this[i]);
     }
    }
    return tc
}

function ats(o,s,e){
    return "<a href=\"javascript:void(0);\" onclick=\"return "+dh.callbackName+".ac(this);\">"+o.slice(s,e).join("</a><a href=\"javascript:void(0);\" onclick=\"return "+dh.callbackName+".ac(this);\">")+"</a>";
}

function getElementpos(e){
    var t = e.offsetTop;
    var l = e.offsetLeft;
    var w = e.offsetWidth;
    var h = e.offsetHeight;
    while(e=e.offsetParent){
     t += e.offsetTop;
     l += e.offsetLeft;
    }
    t += h;
    return {top: t,left: l,width: w,height: h}
}

var dhPopMenu;

function showPop(str){
    if(dh.targetObj!=null){
     var posi = getElementpos(dh.targetObj);
     //应用dhLayer类作为结果集容器
     dhPopMenu = new dhlayer();
     dhPopMenu.border = "1px solid #808080";
     dhPopMenu.background = "lightyellow";
     dhPopMenu.padding = "0px";
     dhPopMenu.content = str;
     dhPopMenu.show(posi.left,posi.top,dh.w,dh.h,document.body);
     dhPopMenu.body.onscroll = function(){showmore();dh.targetObj.focus();}
     dhPopMenu.body.onmouseup = function(){dh.targetObj.focus();}
    }
}

var selectedoption = 0;

var oldvalue = null;

//choose the result use mouse
this.ac = function(o){
    if(this.targetObj!=null){
     oldvalue = this.targetObj.value = o.innerHTML;
    }
    dh.selectedoption = 0;
    return false;
}

//匹配
function searchKey(e){
    if(e!=13 && e!=38 && e!=40 && e!=37 && e!=39){
     var str = dh.targetObj.value;
     if(str!=oldvalue){
      if(str.replace(/\s/g,"") != ""){
       tempArr = dh.datasource.contains(str);
       totalL = tempArr.length;
       startL = 0;
       if(100<totalL){
        endL = 100;
       }else{
        endL = totalL;
       }
       showPop(ats(tempArr,startL,endL));
       selectedoption = 0;
      }
      oldvalue = str;
     }
     if(typeof dhPopMenu=="object" && dhPopMenu.childNodes[selectedoption]){
      dhPopMenu.childNodes[selectedoption].style.border = "1px dotted #630";
      dhPopMenu.childNodes[selectedoption].style.color = "red";
     }
    }
}

//追加数据
function showmore(){
    if(endL<totalL){
     if(typeof dhPopMenu=="object"){
      var ch = dhPopMenu.body.scrollHeight;
      var sh = dhPopMenu.body.scrollTop;
      if(ch-sh<=dh.h){
       startL = endL;
       if(100<totalL-endL){
        endL += 100;
       }else{
        endL += totalL-endL;
       }
       if(document.all){
        dhPopMenu.body.insertAdjacentHTML("beforeEnd",ats(tempArr,startL,endL))
       }else{
        dhPopMenu.body.innerHTML += ats(tempArr,startL,endL);
       }
      }
     }
    }
}

function pressKey(e){
    switch(e){
     case 13:
      if(typeof dhPopMenu=="object" && dhPopMenu.childNodes[selectedoption]){
       if(dh.targetObj!=null){
        oldvalue = dh.targetObj.value = dhPopMenu.childNodes[selectedoption].innerHTML;
       }
       dhPopMenu.hide();
       selectedoption = 0;
       return false;
      }
      break;
     case 38:
      if(typeof dhPopMenu=="object"){
       if(0<selectedoption){
        dhPopMenu.childNodes[selectedoption].style.border = "none";
        dhPopMenu.childNodes[selectedoption].style.color = "";
        selectedoption--;
        dhPopMenu.childNodes[selectedoption].style.border = "1px dotted #630";
        dhPopMenu.childNodes[selectedoption].style.color = "red";
        dhPopMenu.childNodes[selectedoption].scrollIntoView();
       }
      }
      break;
     case 40:
      if(typeof dhPopMenu=="object"){
       if(dhPopMenu.childNodes.length>1 && selectedoption<dhPopMenu.childNodes.length-1){
        dhPopMenu.childNodes[selectedoption].style.border = "none";
        dhPopMenu.childNodes[selectedoption].style.color = "";
       }
       if(selectedoption<dhPopMenu.childNodes.length-1){
        selectedoption++;
        dhPopMenu.childNodes[selectedoption].style.border = "1px dotted #630";
        dhPopMenu.childNodes[selectedoption].style.color = "red";
        dhPopMenu.childNodes[selectedoption].scrollIntoView();
       }
      }
      break;
     default:break;
    }
}

this.setup = function(){
    var targetObj = this.targetObj;
    if(targetObj!=null){
     targetObj.onkeydown = function(e){e=e || window.event; e=e.which || e.keyCode;pressKey(e);}
     targetObj.onkeyup = function(e){e=e || window.event; e=e.which || e.keyCode;searchKey(e);}
    }
}
}