/*************************************************************************
     This code is from Dynamic Web Coding at dyn-web.com
     Copyright 2001-2008 by Sharon Paine 
     See Terms of Use at www.dyn-web.com/business/terms.php
     regarding conditions under which you may use this code.
     This notice must be retained in the code as is!
     
     version date: Aug 2008
 *************************************************************************/
 
 // horizId only needed for horizontal scrolling
 function dw_scrollObj(wndoId, lyrId, horizId) {
     var wn = document.getElementById(wndoId);
     this.id = wndoId; dw_scrollObj.col[this.id] = this;
     this.animString = "dw_scrollObj.col." + this.id;
     this.load(lyrId, horizId);
     
     if (wn.addEventListener) {
         wn.addEventListener('DOMMouseScroll', dw_scrollObj.doOnMouseWheel, false);
     } 
     wn.onmousewheel = dw_scrollObj.doOnMouseWheel;
 }
 
 dw_scrollObj.isSupported = function () {
     if ( document.getElementById && document.getElementsByTagName 
          && document.addEventListener || document.attachEvent ) {
         return true;
     }
     return false;
 }
 
 dw_scrollObj.col = {}; // collect instances
 dw_scrollObj.defaultSpeed = dw_scrollObj.prototype.speed = 100; // default for mouseover or mousedown scrolling
 dw_scrollObj.defaultSlideDur = dw_scrollObj.prototype.slideDur = 500; // default duration of glide onclick
 
 // pseudo events 
 dw_scrollObj.prototype.on_load = function() {} // when dw_scrollObj initialized or new layer loaded
 dw_scrollObj.prototype.on_scroll = function() {}
 dw_scrollObj.prototype.on_scroll_start = function() {}
 dw_scrollObj.prototype.on_scroll_stop = function() {} // when scrolling has ceased (mouseout/up)
 dw_scrollObj.prototype.on_scroll_end = function() {} // reached end
 dw_scrollObj.prototype.on_update = function() {} // called in updateDims
 
 dw_scrollObj.prototype.on_glidescroll = function() {}
 dw_scrollObj.prototype.on_glidescroll_start = function() {}
 dw_scrollObj.prototype.on_glidescroll_stop = function() {} // destination (to/by) reached
 dw_scrollObj.prototype.on_glidescroll_end = function() {} // reached end
 
 dw_scrollObj.prototype.load = function(lyrId, horizId) {
     var wndo, lyr;
     if (this.lyrId) { // layer currently loaded?
         lyr = document.getElementById(this.lyrId);
         lyr.style.visibility = "hidden";
     }
     this.lyr = lyr = document.getElementById(lyrId); // hold this.lyr?
     this.lyr.style.position = 'absolute'; 
     this.lyrId = lyrId; // hold id of currently visible layer
     this.horizId = horizId || null; // hold horizId for update fn
     wndo = document.getElementById(this.id);
     this.y = 0; this.x = 0; this.shiftTo(0,0);
     this.getDims(wndo, lyr); 
     lyr.style.visibility = "visible";
     this.ready = true; this.on_load(); 
 }
 
 dw_scrollObj.prototype.shiftTo = function(x, y) {
     if (this.lyr) {
         this.lyr.style.left = (this.x = x) + "px"; 
         this.lyr.style.top = (this.y = y) + "px";
     }
 }
 
 dw_scrollObj.prototype.getX = function() { return this.x; }
 dw_scrollObj.prototype.getY = function() { return this.y; }
 
 dw_scrollObj.prototype.getDims = function(wndo, lyr) { 
     this.wd = this.horizId? document.getElementById( this.horizId ).offsetWidth: lyr.offsetWidth;
     this.maxX = (this.wd - wndo.offsetWidth > 0)? this.wd - wndo.offsetWidth: 0;
     this.maxY = (lyr.offsetHeight - wndo.offsetHeight > 0)? lyr.offsetHeight - wndo.offsetHeight: 0;
 }
 
 dw_scrollObj.prototype.updateDims = function() {
     var wndo = document.getElementById(this.id);
     var lyr = document.getElementById( this.lyrId );
     this.getDims(wndo, lyr);
     this.on_update();
 }
 
 // for mouseover/mousedown scrolling
 dw_scrollObj.prototype.initScrollVals = function(deg, speed) {
     if (!this.ready) return; 
     if (this.timerId) {
         clearInterval(this.timerId); this.timerId = 0;
     }
     this.speed = speed || dw_scrollObj.defaultSpeed;
     this.fx = (deg == 0)? -1: (deg == 180)? 1: 0;
     this.fy = (deg == 90)? 1: (deg == 270)? -1: 0;
     this.endX = (deg == 90 || deg == 270)? this.x: (deg == 0)? -this.maxX: 0; 
     this.endY = (deg == 0 || deg == 180)? this.y: (deg == 90)? 0: -this.maxY;
     this.lyr = document.getElementById(this.lyrId);
     this.lastTime = new Date().getTime();
     this.on_scroll_start(this.x, this.y);  
     this.timerId = setInterval(this.animString + ".scroll()", 10);    
 }
 
 dw_scrollObj.prototype.scroll = function() {
     var now = new Date().getTime();
     var d = (now - this.lastTime)/1000 * this.speed;
     if (d > 0) { 
         var x = this.x + Math.round(this.fx * d); var y = this.y + Math.round(this.fy * d);
         if ( ( this.fx == -1 && x > -this.maxX ) || ( this.fx == 1 && x < 0 ) || 
                 ( this.fy == -1 && y > -this.maxY ) || ( this.fy == 1 && y < 0 ) ) 
        {
             this.lastTime = now;
             this.shiftTo(x, y);
             this.on_scroll(x, y);
         } else {
             clearInterval(this.timerId); this.timerId = 0;
             this.shiftTo(this.endX, this.endY);
             this.on_scroll(this.endX, this.endY);
             this.on_scroll_end(this.endX, this.endY);
         }
     }
 }
 
 // when scrolling has ceased (mouseout/up)
 dw_scrollObj.prototype.ceaseScroll = function() {
     if (!this.ready) return;
     if (this.timerId) {
         clearInterval(this.timerId); this.timerId = 0; 
     }
     this.on_scroll_stop(this.x, this.y); 
 }
 
 // glide onclick scrolling
 dw_scrollObj.prototype.initScrollByVals = function(dx, dy, dur) {
     if ( !this.ready || this.sliding ) return;
     this.startX = this.x; this.startY = this.y;
     this.destX = this.destY = this.distX = this.distY = 0;
     if (dy < 0) {
         this.distY = (this.startY + dy >= -this.maxY)? dy: -(this.startY  + this.maxY);
     } else if (dy > 0) {
         this.distY = (this.startY + dy <= 0)? dy: -this.startY;
     }
     if (dx < 0) {
         this.distX = (this.startX + dx >= -this.maxX)? dx: -(this.startX + this.maxX);
     } else if (dx > 0) {
         this.distX = (this.startX + dx <= 0)? dx: -this.startX;
     }
     this.destX = this.startX + this.distX; this.destY = this.startY + this.distY;
     this.glideScrollPrep(this.destX, this.destY, dur);
 }
 
 dw_scrollObj.prototype.initScrollToVals = function(destX, destY, dur) {
     if ( !this.ready || this.sliding ) return;
     this.startX = this.x; this.startY = this.y;
     this.destX = -Math.max( Math.min(destX, this.maxX), 0);
     this.destY = -Math.max( Math.min(destY, this.maxY), 0);
     this.distY = this.destY - this.startY;
     this.distX = this.destX - this.startX;
     this.glideScrollPrep(this.destX, this.destY, dur);
 }
 
 dw_scrollObj.prototype.glideScrollPrep = function(destX, destY, dur) {
     this.slideDur = (typeof dur == 'number')? dur: dw_scrollObj.defaultSlideDur;
     this.per = Math.PI/(2 * this.slideDur); this.sliding = true;
     this.lyr = document.getElementById(this.lyrId); 
     this.startTime = new Date().getTime();
     this.timerId = setInterval(this.animString + ".doGlideScroll()",10);
     this.on_glidescroll_start(this.startX, this.startY);
 }
 
 dw_scrollObj.prototype.doGlideScroll = function() {
     var elapsed = new Date().getTime() - this.startTime;
     if (elapsed < this.slideDur) {
         var x = this.startX + Math.round( this.distX * Math.sin(this.per*elapsed) );
         var y = this.startY + Math.round( this.distY * Math.sin(this.per*elapsed) );
         this.shiftTo(x, y); 
         this.on_glidescroll(x, y);
     } else {	// if time's up
         clearInterval(this.timerId); this.timerId = 0; this.sliding = false;
         this.shiftTo(this.destX, this.destY);
         this.on_glidescroll(this.destX, this.destY);
         this.on_glidescroll_stop(this.destX, this.destY);
         // end of axis reached ? 
         if ( this.distX && (this.destX == 0 || this.destX == -this.maxX) 
           || this.distY && (this.destY == 0 || this.destY == -this.maxY) ) { 
             this.on_glidescroll_end(this.destX, this.destY);
         } 
     }
 }
 
 //  resource: http://adomas.org/javascript-mouse-wheel/
 dw_scrollObj.handleMouseWheel = function(id, delta) {
     var wndo = dw_scrollObj.col[id];
     var x = wndo.x;
     var y = wndo.y;
     wndo.on_scroll_start(x,y);
     var ny;
     ny = 12  * delta + y
     ny = (ny < 0 && ny >= -wndo.maxY)? ny: (ny < -wndo.maxY)? -wndo.maxY: 0;
     wndo.shiftTo(x, ny);
     wndo.on_scroll(x, ny);
 }
 
 dw_scrollObj.doOnMouseWheel = function(e) {
     var delta = 0;
     if (!e) e = window.event;
     if (e.wheelDelta) { /* IE/Opera. */
         delta = e.wheelDelta/120;
         if (window.opera) delta = -delta;
     } else if (e.detail) { // Mozilla 
         delta = -e.detail/3;
     }
     if (delta) { // > 0 up, < 0 down
         dw_scrollObj.handleMouseWheel(this.id, delta);
     }
     if (e.preventDefault) e.preventDefault();
     e.returnValue = false;
 }
 
 dw_scrollObj.GeckoTableBugFix = function() {} // no longer need old bug fix
 
 
 // Get position of el within layer (oCont) sOff: 'left' or 'top'
 // Assumes el is within oCont
 function dw_getLayerOffset(el, oCont, sOff) {
     var off = "offset" + sOff.charAt(0).toUpperCase() + sOff.slice(1);
     var val = el[off];
     while ( (el = el.offsetParent) != oCont ) 
         val += el[off];
     var clientOff = off.replace("offset", "client");
     if ( el[clientOff] ) val += el[clientOff];
     return val;
 }
 
 /////////////////////////////////////////////////////////////////////
 // Reminder about licensing requirements
 // See Terms of Use at www.dyn-web.com/business/terms.php
 // OK to remove after purchasing a license or if using on a personal site.
 function dw_checkAuth() {
     var loc = window.location.hostname.toLowerCase();
     var msg = 'A license is required for commercial use of this code.\n' + 
         'Please adhere to our Terms of Use if you use dyn-web code.';
     if ( !( loc == '' || loc == '127.0.0.1' || loc.indexOf('localhost') != -1 
          || loc.indexOf('192.168.') != -1 || loc.indexOf('dyn-web.com') != -1 ) ) {
         //alert(msg);
     }
 }
 dw_Event.add( window, 'load', dw_checkAuth);
 /////////////////////////////////////////////////////////////////////