//**************************************************
// TLDropDownBoxLib.js
// Author: Tong Lim 
// Version: 1.3
// Date: 8/4/2006
// Update: 8/31/2006
// Example:
//     init: TLDropDownBox.initialize('bodyText')
//           TLDropDownBox.initialize('bodyText',0,'fast',1)
//           TLDropDownBox.startSlide('bodyText')
//***************************************************


function TLDropDownBoxLib() {

    var v_imgSwap=0;
    elementObjects = new Array(); // array of all html element object

	function menuStruct (p1) {
        this.box_height;
        this.menuState;
        this.elementObj;
        this.htmlValue;
        this.increment;
        this.inc_num = 10;
        this.clearIntervalValue;
        this.opacityValue = 0;
        this.speed = 100;
		this.showOpacity = 0;
		this.temp;
    }

    // param: p1 = id name of the div
    // param: p2 = menu state, 0 = fold, 1=down
	// param: speed = fast or normal
    // param: showOpacity = 1 for show, 0 no show
    this.initialize = function(p1, p2, speed, showOpacity) {
        var elemObj = this.getElementObj(p1);
        var v_menuStruct = new menuStruct();
        v_menuStruct.elementObj = elemObj;
        v_menuStruct.box_height = elemObj.offsetHeight;
        v_menuStruct.htmlValue = elemObj.innerHTML;
		v_menuStruct.menuState = 0;
        if (showOpacity != null)
			v_menuStruct.showOpacity = showOpacity;
		if (speed == 'fast')
			v_menuStruct.speed = 0;        
        if (p2 == 0) {
            this.hideElement(elemObj);
            elemObj.innerHTML = "";
            elemObj.style.height = "0px";
            v_menuStruct.menuState = 1;
        }
        elementObjects[elemObj.id] = v_menuStruct;
    }
    
    // p1 = name of the div
    this.updateHtml = function(p1) {
        var elemObj = getObj(p1);
        if(elemObj) {
	        var v_menuStruct = elementObjects[elemObj.id];
			v_menuStruct.htmlValue = elemObj.innerHTML;
			v_menuStruct.box_height = elemObj.offsetHeight;
			v_menuStruct.elementObj = elemObj;
		} else {
			setTimeout("TLDropDownBox.updateHtml(" + p1 + ")", 100);
		}
    }

    // p1 = name of the div
    this.getHtml = function(p1) {
        var elemObj = this.getElementObj(p1);
        var v_menuStruct = elementObjects[elemObj.id];
		return v_menuStruct.htmlValue;

    }

	// p1 = name of the div
	// delay = delay speed in seconds
	this.startDownUp = function(p1, delay) {
		var v_delay = 3000;
		if (delay != null) {
			v_delay * 1000;	
		}		
		this.startSlide(p1);
		setTimeout("TLDropDownBox.startSlide(" + p1 + ")", v_delay); 
		
	}
	
	// p1 = name of the div id
	// state = the current menu state
    this.startSlide = function(p1, state) {
        var elemObj = this.getElementObj(p1);
        var v_menuStruct = elementObjects[elemObj.id];
        var v_idStr =  v_menuStruct.elementObj.id;

		if(v_menuStruct.box_height > v_menuStruct.inc_num)
	        v_menuStruct.increment = parseInt(v_menuStruct.box_height / v_menuStruct.inc_num);
	    else 
	    	v_menuStruct.increment = v_menuStruct.box_height;
		
		if(state) {
			v_menuStruct.menuState = state;
		}
		
        if (v_menuStruct.menuState == 0) {
            v_menuStruct.temp = v_menuStruct.box_height;
            v_menuStruct.opacityValue = v_menuStruct.inc_num;
            if (v_menuStruct.speed == 0)
				slideUp2(v_menuStruct.elementObj);
			else
				v_menuStruct.clearIntervalValue = setInterval('TLDropDownBox.slideUp("' + v_idStr + '")', v_menuStruct.speed);
            
        }
        else {
            v_menuStruct.temp = 0;
            this.showElement(elemObj);
            v_menuStruct.opacityValue = 1;
            if (v_menuStruct.speed == 0)
				slideDown2(v_menuStruct.elementObj);
			else
				v_menuStruct.clearIntervalValue = setInterval('TLDropDownBox.slideDown("' + v_idStr + '")', v_menuStruct.speed);
            
        }
    }

    // p1 = id of the div
    function slideDown2 (obj) {
        var v_menuStruct = elementObjects[obj.id];
        var v_height = 0;

        while (v_height < v_menuStruct.box_height) {
    		if (v_menuStruct.showOpacity == 1) {
                setOpacity(v_menuStruct.elementObj, v_menuStruct.opacityValue);
    			v_menuStruct.opacityValue += 1;
    		}
    		v_menuStruct.elementObj.style.height = v_height + "px";
    		v_height = v_height + v_menuStruct.increment;
        }
        v_menuStruct.elementObj.innerHTML = v_menuStruct.htmlValue;
        v_menuStruct.menuState = 0;
        v_menuStruct.elementObj.style.height = v_menuStruct.box_height + "px";
    }

    // p1 = id of the div
    this.slideDown = function(p1) {
        var elemObj = this.getElementObj(p1);
        var v_menuStruct = elementObjects[elemObj.id];

        v_menuStruct.temp = v_menuStruct.temp + v_menuStruct.increment;

		if (v_menuStruct.showOpacity == 1) {
			// opacity of text area
            setOpacity(v_menuStruct.elementObj, v_menuStruct.opacityValue);
			v_menuStruct.opacityValue += 1;
		}

        // stop the timer
        if (v_menuStruct.temp >= v_menuStruct.box_height) {
			clearInterval(v_menuStruct.clearIntervalValue);
            v_menuStruct.menuState = 0;
			v_menuStruct.temp = v_menuStruct.box_height;
			v_menuStruct.elementObj.innerHTML = v_menuStruct.htmlValue;
		}
        v_menuStruct.elementObj.style.height = v_menuStruct.temp + "px";
    }


    // p1 = id of the div
    function slideUp2 (obj) {
        var v_menuStruct = elementObjects[obj.id];
        var v_height = v_menuStruct.box_height;
        v_menuStruct.elementObj.innerHTML = "";
        
        while (v_height > 0) {
    		if (v_menuStruct.showOpacity == 1) {
                setOpacity(v_menuStruct.elementObj, v_menuStruct.opacityValue);
    			v_menuStruct.opacityValue -= 1;
    		}
    		v_menuStruct.elementObj.style.height = v_height + "px";
    		v_height = v_height - v_menuStruct.increment;
        }

        TLDropDownBox.hideElement(v_menuStruct.elementObj);
        v_menuStruct.menuState = 1;
        v_menuStruct.elementObj.style.height = "0px";
    }

    // p1 = id of the div
    this.slideUp = function (p1) {
        var elemObj = this.getElementObj(p1);
        var v_menuStruct = elementObjects[elemObj.id];

		if (v_menuStruct.box_height  == v_menuStruct.temp)
			elemObj.innerHTML = "";
        v_menuStruct.temp = v_menuStruct.temp - v_menuStruct.increment;

		if (v_menuStruct.showOpacity == 1) {
			// for opacity
			setOpacity(v_menuStruct.elementObj, v_menuStruct.opacityValue);
			v_menuStruct.opacityValue -= 1;
		}

		// stop the timer
        if (v_menuStruct.temp <= 0) {
            this.hideElement(elemObj);
			clearInterval(v_menuStruct.clearIntervalValue);
            v_menuStruct.menuState = 1;
            v_menuStruct.temp = 0;
		}
        v_menuStruct.elementObj.style.height = v_menuStruct.temp + "px";
    }


    // param: obj = element object
    // param: opacityValue = opacity value
    function setOpacity (obj, opacityValue) {
		if (obj.style.filter != undefined)
			obj.style.filter = 'alpha(opacity=' + opacityValue * 10 + ')';
		if (obj.style.opacity != undefined)
			obj.style.opacity = opacityValue / 10;
    }
    

    //--------------------------------------------
	// Desc: swap image
	// param: p1 = object
	// param: p2 = image one
	// param: p3 = image two
	// return: nothing
	this.imgSwap = function (p1, p2, p3) {
		if (v_imgSwap == p3 || v_imgSwap == 0) {
			p1.src = p2;
			v_imgSwap = p2;
			return 1;
		} else {
			p1.src = p3;
			v_imgSwap = p3;
			return 2;
		}	
	}


	//--------------------------------------------
	// Desc: Function to get an obj of element. pass in an id and it return the obj
	// param: id = string of id
	// return: an object
	this.getElementObj = function(param) {
		if (typeof param == 'object') {
            return param;
        }
        else {
            if (document.getElementById) { // W3C - Explorer 5+ and Netscape 6+
                return  document.getElementById(param);
    		}
    		else if (document.all) { // Explorer 4
                return document.all[param];
    		}
            else if (document.layers) {  // NS4
                return document.layers[param];
    		}
        }
	}


	//------------------------------------------
	// Desc: Function to hide an element. Pass in an id or object and it will hide the element.
	// param: id = id string or an object
	// return: nothing
	this.hideElement = function (p1) {
		var obj = this.getElementObj(p1);
		if (obj != undefined) {
			if (document.layers){ // Netscape 4
				obj.visibility = "hide";
			}
			else { // W3C - Explorer 5+ and Netscape 6+
				obj.style.visibility = "hidden";
			}
		}
	}


	//--------------------------------------
	// Desc: Function to show an element. Pass in an id or object and it will show the element.
	// param: id = id string or an object
	// return: nothing
	this.showElement = function (p1) {
		var obj = this.getElementObj(p1);
		if (obj != undefined) {
			if(document.layers) { // Netscape 4
				obj.visibility = "show";
			}
			else { // W3C - Explorer 5+ and Netscape 6+
				obj.style.visibility = "visible";
			}
		}
	}

} // end of TLDropDownBoxLib()

var TLDropDownBox = new TLDropDownBoxLib();