/*************************************************************************
    dw_event.js (version date Feb 2004)
        
    This code is from Dynamic Web Coding at http://www.dyn-web.com/
    See Terms of Use at http://www.dyn-web.com/bus/terms.html
    regarding conditions under which you may use this code.
    This notice must be retained in the code as is!
*************************************************************************/
/* 
    dw_scrollObj.js  version date: June 2004 
    contains constructor and basic methods for scrolling layers.
    Use with dw_hoverscroll.js and/or dw_glidescroll.js,
    and for scrollbars: dw_scroll-aux.js and dw_slidebar.js
*/

dw_scrollObjs = {};
dw_scrollObj.speed = 100; // default speed for mouseover scrolling
//  constructor arguments: id of layer containing scrolling layers (clipped layer), id of layer to scroll, 
//	id of table or other element that scrolling content is nested in. 
//	ns6+/moz need that extra container to get width for horizontal scrolling.
//	(not needed for vertical scrolling)
function dw_scrollObj(wnId, lyrId, cntId) {
  this.id = wnId; dw_scrollObjs[this.id] = this;
  this.animString = "dw_scrollObjs." + this.id;
  this.load(lyrId, cntId);
}

dw_scrollObj.loadLayer = function(wnId, id, cntId) {
  if ( dw_scrollObjs[wnId] ) dw_scrollObjs[wnId].load(id, cntId);
}

dw_scrollObj.prototype.load = function(lyrId, cntId) {
  if (!document.getElementById) return;
  var wndo, lyr;
  if (this.lyrId) {
    lyr = document.getElementById(this.lyrId);
    lyr.style.visibility = "hidden";
  }
  lyr = document.getElementById(lyrId);
  wndo = document.getElementById(this.id);
  lyr.style.top = this.y = 0; lyr.style.left = this.x = 0;
  this.maxY = (lyr.offsetHeight - wndo.offsetHeight > 0)? lyr.offsetHeight - wndo.offsetHeight: 0;
  this.wd = cntId? document.getElementById(cntId).offsetWidth: lyr.offsetWidth;
  this.maxX = (this.wd - wndo.offsetWidth > 0)? this.wd - wndo.offsetWidth: 0;
  this.lyrId = lyrId; // hold id of currently visible layer
  lyr.style.visibility = "visible";
  this.on_load(); this.ready = true;
}

dw_scrollObj.prototype.on_load = function() {}  

dw_scrollObj.prototype.shiftTo = function(lyr, x, y) {
  lyr.style.left = (this.x = x) + "px"; 
  lyr.style.top = (this.y = y) + "px";
}

// remove layers from table for ns6+/mozilla (needed for scrolling inside tables)
dw_scrollObj.GeckoTableBugFix = function() {
  var i, wndo, holderId, holder, x, y;
	if ( navigator.userAgent.indexOf("Gecko") > -1 && navigator.userAgent.indexOf("Firefox") == -1 ) {
    dw_scrollObj.hold = []; // holds id's of wndo and its container
    for (i=0; arguments[i]; i++) {
      if ( dw_scrollObjs[ arguments[i] ] ) {
        wndo = document.getElementById( arguments[i] );
        holderId = wndo.parentNode.id;
        holder = document.getElementById(holderId);
        document.body.appendChild( holder.removeChild(wndo) );
        wndo.style.zIndex = 1000;
        x = holder.offsetLeft; y = holder.offsetTop;
        wndo.style.left = x + "px"; wndo.style.top = y + "px";
        dw_scrollObj.hold[i] = [ arguments[i], holderId ];
      }
    }
   window.addEventListener("resize", dw_scrollObj.rePositionGecko, true);
  }
}

// ns6+/mozilla need to reposition layers onresize when scrolling inside tables.
dw_scrollObj.rePositionGecko = function() {
  var i, wndo, holder, x, y;
  if (dw_scrollObj.hold) {
    for (i=0; dw_scrollObj.hold[i]; i++) {
      wndo = document.getElementById( dw_scrollObj.hold[i][0] );
      holder = document.getElementById( dw_scrollObj.hold[i][1] );
      x = holder.offsetLeft; y = holder.offsetTop;
      wndo.style.left = x + "px"; wndo.style.top = y + "px";
    }
  }
}


function initScrollLayer() {
  // arguments: id of layer containing scrolling layers (clipped layer), id of layer to scroll, 
  // if horizontal scrolling, id of element containing scrolling content (table?)
  var wndo = new dw_scrollObj('wn', 'lyr1');
  
  // bSizeDragBar set true by default (explained at www.dyn-web.com/dhtml/scroll/ )
  // wndo.bSizeDragBar = false;
  
  // arguments: dragBar id, track id, axis ("v" or "h"), x offset, y offset
  // (x/y offsets of dragBar in track)
  wndo.setUpScrollbar("dragBar", "track", "v", 1, 1);
  
  // pass id('s) of scroll area(s) if inside table(s)
  // i.e., if you have 3 (with id's wn1, wn2, wn3): dw_scrollObj.GeckoTableBugFix('wn1', 'wn2', 'wn3');
  dw_scrollObj.GeckoTableBugFix('wn'); 
}

var dw_event = {
  
  add: function(obj, etype, fp, cap) {
    cap = cap || false;
    if (obj.addEventListener) obj.addEventListener(etype, fp, cap);
    else if (obj.attachEvent) obj.attachEvent("on" + etype, fp);
  }, 

  remove: function(obj, etype, fp, cap) {
    cap = cap || false;
    if (obj.removeEventListener) obj.removeEventListener(etype, fp, cap);
    else if (obj.detachEvent) obj.detachEvent("on" + etype, fp);
  }, 

  DOMit: function(e) { 
    e = e? e: window.event;
    e.tgt = e.srcElement? e.srcElement: e.target;
    
    if (!e.preventDefault) e.preventDefault = function () { return false; }
    if (!e.stopPropagation) e.stopPropagation = function () { if (window.event) window.event.cancelBubble = true; }
        
    return e;
  }
  
}

/*************************************************************************
  This code is from Dynamic Web Coding at www.dyn-web.com
  Copyright 2001-4 by Sharon Paine 
  See Terms of Use at www.dyn-web.com/bus/terms.html
  regarding conditions under which you may use this code.
  This notice must be retained in the code as is!
*************************************************************************/

/* dw_hoverscroll.js  version date: June 2004 
   mouseover scrolling for dw_scrollObj (in dw_scrollObj.js)  */

dw_scrollObj.stopScroll = function(wnId) {
  if ( dw_scrollObjs[wnId] ) dw_scrollObjs[wnId].endScroll();
}

// increase speed onmousedown of scroll links
dw_scrollObj.doubleSpeed = function(wnId) {
  if ( dw_scrollObjs[wnId] ) dw_scrollObjs[wnId].speed *= 2;
}

dw_scrollObj.resetSpeed = function(wnId) {
  if ( dw_scrollObjs[wnId] ) dw_scrollObjs[wnId].speed /= 2;
}

// algorithms for time-based scrolling and scrolling onmouseover at any angle adapted from youngpup.net
dw_scrollObj.initScroll = function(wnId, deg, sp) {
  if ( dw_scrollObjs[wnId] ) {
    var cosine, sine;
    if (typeof deg == "string") {
      switch (deg) {
        case "up"    : deg = 90;  break;
        case "down"  : deg = 270; break;
        case "left"  : deg = 180; break;
        case "right" : deg = 0;   break;
        default: 
          alert("Direction of scroll in mouseover scroll links should be 'up', 'down', 'left', 'right' or number: 0 to 360.");
       }
    } 
    deg = deg % 360;
    if (deg % 90 == 0) {
      cosine = (deg == 0)? -1: (deg == 180)? 1: 0;
      sine = (deg == 90)? 1: (deg == 270)? -1: 0;
    } else {
      var angle = deg * Math.PI/180;
      cosine = -Math.cos(angle); sine = Math.sin(angle);
    }
    dw_scrollObjs[wnId].fx = cosine / ( Math.abs(cosine) + Math.abs(sine) );
    dw_scrollObjs[wnId].fy = sine / ( Math.abs(cosine) + Math.abs(sine) );
    dw_scrollObjs[wnId].endX = (deg == 90 || deg == 270)? dw_scrollObjs[wnId].x:
      (deg < 90 || deg > 270)? -dw_scrollObjs[wnId].maxX: 0; 
    dw_scrollObjs[wnId].endY = (deg == 0 || deg == 180)? dw_scrollObjs[wnId].y: 
      (deg < 180)? 0: -dw_scrollObjs[wnId].maxY;
    dw_scrollObjs[wnId].startScroll(sp);
  }
}

// speed (optional) to override default speed (set in dw_scrollObj.speed)
dw_scrollObj.prototype.startScroll = function(speed) {
  if (!this.ready) return; if (this.timerId) clearInterval(this.timerId);
  this.speed = speed || dw_scrollObj.speed;
  this.lyr = document.getElementById(this.lyrId);
  this.lastTime = ( new Date() ).getTime();
  this.on_scroll_start();  
  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 + this.fx * d; var y = this.y + this.fy * d;
    if (this.fx == 0 || this.fy == 0) { // for horizontal or vertical scrolling
      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(this.lyr, x, y);
        this.on_scroll(x, y);
      } else {
        clearInterval(this.timerId); this.timerId = 0;
        this.shiftTo(this.lyr, this.endX, this.endY);
        this.on_scroll_end(this.endX, this.endY);
      }
    } else { // for scrolling at an angle (stop when reach end on one axis)
      if ( ( this.fx < 0 && x >= -this.maxX && this.fy < 0 && y >= -this.maxY ) ||
        ( this.fx > 0 && x <= 0 && this.fy > 0 && y <= 0 ) ||
        ( this.fx < 0 && x >= -this.maxX && this.fy > 0 && y <= 0 ) ||
        ( this.fx > 0 && x <= 0 && this.fy < 0 && y >= -this.maxY ) ) {
        this.lastTime = now;
        this.shiftTo(this.lyr, x, y);
        this.on_scroll(x, y);
      } else {
        clearInterval(this.timerId); this.timerId = 0;
        this.on_scroll_end(this.x, this.y);
      }
    }
  }
}

dw_scrollObj.prototype.endScroll = function() {
  if (!this.ready) return;
  if (this.timerId) clearInterval(this.timerId);
  this.timerId = 0;  this.lyr = null;
}

dw_scrollObj.prototype.on_scroll = function() {}
dw_scrollObj.prototype.on_scroll_start = function() {}
dw_scrollObj.prototype.on_scroll_end = function() {}

/*
  dw_scroll_aux.js    version date: May 2004  
  integrates scrolling layers code with scrollbar code (dw_scrollbar.js)
*/

// Size dragBar according to layer size?  
dw_scrollObj.prototype.bSizeDragBar = true;

dw_scrollObj.prototype.setUpScrollbar = function(id, trkId, axis, offx, offy) {
  if (!document.getElementById) return;
  var bar = document.getElementById(id);
  var trk = document.getElementById(trkId);
  dw_slidebar.init(bar, trk, axis, offx, offy);
  // connect dw_slidebar with dw_scrollObj
  bar.wn = dw_scrollObjs[this.id]; // scroll area object this bar connected to
  if (axis == "v") this.vBarId = id; else this.hBarId = id;
  // also called on_load (i.e., when layer loaded), but in case h and v scrollbars, need to call here too
  if (this.bSizeDragBar) this.setBarSize();
  bar.on_drag_start = bar.on_slide_start = dw_scrollObj.getWndoLyrRef;
  bar.on_drag_end =   bar.on_slide_end =   dw_scrollObj.tossWndoLyrRef;
  bar.on_drag =       bar.on_slide =       dw_scrollObj.UpdateWndoLyrPos;
}

// for these 3 functions (assigned to bar.on_drag/slide...) "this" refers to bar
// get/discard ref to layer visible in scroll area
dw_scrollObj.getWndoLyrRef = function()  { this.wnLyr = document.getElementById(this.wn.lyrId); }
dw_scrollObj.tossWndoLyrRef = function() { this.wnLyr = null; }
// keep position of scrolling layer in synch with slide/drag of bar
dw_scrollObj.UpdateWndoLyrPos = function(x, y) {
  var nx, ny;
  if (this.axis == "v") {
    nx = this.wn.x; // floating point values for loaded layer's position held in shiftTo method
    ny = -(y - this.minY) * ( this.wn.maxY / (this.maxY - this.minY) ) || 0;
  } else {
    ny = this.wn.y;
    nx = -(x - this.minX) * ( this.wn.maxX / (this.maxX - this.minX) ) || 0;
  }
  this.wn.shiftTo(this.wnLyr, nx, ny);
}

// Keep position of dragBar in sync with position of layer onscroll
dw_scrollObj.prototype.updateScrollbar = function(x, y) {
  var nx, ny;
  if ( this.vBarId ) {
    if (!this.maxY) return;
    ny = -( y * ( (this.vbar.maxY - this.vbar.minY) / this.maxY ) - this.vbar.minY );
    ny = Math.min( Math.max(ny, this.vbar.minY), this.vbar.maxY);  
    nx = parseInt(this.vbar.style.left);
    this.vbar.style.left = nx + "px"; this.vbar.style.top = ny + "px";
  } if ( this.hBarId ) {
    if (!this.maxX) return;
    nx = -( x * ( (this.hbar.maxX - this.hbar.minX) / this.maxX ) - this.hbar.minX );
    nx = Math.min( Math.max(nx, this.hbar.minX), this.hbar.maxX);
    ny = parseInt(this.hbar.style.top);
    this.hbar.style.left = nx + "px"; this.hbar.style.top = ny + "px";
  } 
  
}

// Restore dragBar to start position when loading new layer
dw_scrollObj.prototype.restoreScrollbars = function() {
  var bar;
  if (this.vBarId) {
    bar = document.getElementById(this.vBarId);
    bar.style.left = bar.minX + "px"; bar.style.top = bar.minY + "px";
  }
  if (this.hBarId) {
    bar = document.getElementById(this.hBarId);
    bar.style.left = bar.minX + "px"; bar.style.top = bar.minY + "px";
  }
}
  
// Size dragBar in proportion to size of content in layer
// called on_load of layer if bSizeDragBar prop true
dw_scrollObj.prototype.setBarSize = function() {
  var bar;
  var lyr = document.getElementById(this.lyrId);
  var wn = document.getElementById(this.id);
  if (this.vBarId) {
    bar = document.getElementById(this.vBarId);
    bar.style.height = (lyr.offsetHeight > wn.offsetHeight)? bar.trkHt / ( lyr.offsetHeight / wn.offsetHeight ) + "px": bar.trkHt - 2*bar.minY + "px";
    bar.maxY = bar.trkHt - bar.offsetHeight - bar.minY; 
  }
  if (this.hBarId) {
    bar = document.getElementById(this.hBarId);
    bar.style.width = (this.wd > wn.offsetWidth)? bar.trkWd / ( this.wd / wn.offsetWidth ) + "px": bar.trkWd - 2*bar.minX + "px";
    bar.maxX = bar.trkWd - bar.offsetWidth - bar.minX; 
  }
}

// called from load method
dw_scrollObj.prototype.on_load = function() { 
  this.restoreScrollbars();
  if (this.bSizeDragBar) this.setBarSize();
}

dw_scrollObj.prototype.on_scroll = dw_scrollObj.prototype.on_slide = function(x,y) { this.updateScrollbar(x,y); }

// obtain and discard references to relevant dragBar
dw_scrollObj.prototype.on_scroll_start = dw_scrollObj.prototype.on_slide_start = function() {
  if ( this.vBarId ) this.vbar = document.getElementById(this.vBarId);
  if ( this.hBarId ) this.hbar = document.getElementById(this.hBarId);
}

dw_scrollObj.prototype.on_scroll_end = dw_scrollObj.prototype.on_slide_end = function(x, y) { 
  this.updateScrollbar(x,y);
  this.lyr = null; this.bar = null; 
}



/*   dw_slidebar.js   version date: Feb 2004   requires dw_event.js   */

// model: Aaron Boodman's dom drag at www.youngpup.net
var dw_slidebar = {
  obj: null,
  slideDur: 500,  // duration of glide onclick of track  
  init: function (bar, track, axis, x, y) {
    x = x || 0; y = y || 0;
    bar.style.left = x + "px"; bar.style.top = y + "px";
    bar.axis = axis; track.bar = bar;
    if (axis == "h") {
      bar.trkWd = track.offsetWidth; // hold for setBarSize
      bar.maxX = bar.trkWd - bar.offsetWidth - x; 
      bar.minX = x; bar.maxY = y; bar.minY = y;
    } else {
      bar.trkHt = track.offsetHeight;
      bar.maxY = bar.trkHt - bar.offsetHeight - y; 
      bar.maxX = x; bar.minX = x; bar.minY = y;
    }
    bar.on_drag_start =  bar.on_drag =   bar.on_drag_end = 
    bar.on_slide_start = bar.on_slide =  bar.on_slide_end = function() {}
    bar.onmousedown = this.startDrag; track.onmousedown = this.startSlide;
  },
  
  startSlide: function(e) { // called onmousedown of track 
    if ( dw_slidebar.aniTimer ) clearInterval(dw_slidebar.aniTimer);
    e = e? e: window.event;
    var bar = dw_slidebar.obj = this.bar; // i.e., track's bar
    e.offX = (typeof e.layerX != "undefined")? e.layerX: e.offsetX;
    e.offY = (typeof e.layerY != "undefined")? e.layerY: e.offsetY;
    bar.startX = parseInt(bar.style.left); bar.startY = parseInt(bar.style.top);
    if (bar.axis == "v") {
      bar.destX = bar.startX;
      bar.destY = (e.offY < bar.startY)? e.offY: e.offY - bar.offsetHeight;
      bar.destY = Math.min( Math.max(bar.destY, bar.minY), bar.maxY );
    } else {
      bar.destX = (e.offX < bar.startX)? e.offX: e.offX - bar.offsetWidth;
      bar.destX = Math.min( Math.max(bar.destX, bar.minX), bar.maxX );
      bar.destY = bar.startY;
    }
    bar.distX = bar.destX - bar.startX; bar.distY = bar.destY - bar.startY;
    dw_slidebar.per = Math.PI/(2 * dw_slidebar.slideDur);
  	dw_slidebar.slideStart = (new Date()).getTime();
    bar.on_slide_start(bar.startX, bar.startY);
  	dw_slidebar.aniTimer = setInterval("dw_slidebar.doSlide()",10);
  },
  
  doSlide: function() {
    if ( !dw_slidebar.obj ) { clearInterval(dw_slidebar.aniTimer); return; }    
    var bar = dw_slidebar.obj;     
    var elapsed = (new Date()).getTime() - this.slideStart;
  	if (elapsed < this.slideDur) {
  		var x = bar.startX + bar.distX * Math.sin(this.per*elapsed);
  		var y = bar.startY + bar.distY * Math.sin(this.per*elapsed);
      bar.style.left = x + "px"; bar.style.top = y + "px";
      bar.on_slide(x, y);
  	} else {	// if time's up
      clearInterval(this.aniTimer);
      bar.style.left = bar.destX + "px"; bar.style.top = bar.destY + "px";
      bar.on_slide_end(bar.destX, bar.destY);
      this.obj = null;
  	}
  },
  
  startDrag: function (e) { // called onmousedown of bar 
    e = dw_event.DOMit(e);
    if ( dw_slidebar.aniTimer ) clearInterval(dw_slidebar.aniTimer);
    var bar = dw_slidebar.obj = this;
    bar.downX = e.clientX; bar.downY = e.clientY;
    bar.startX = parseInt(bar.style.left);
    bar.startY = parseInt(bar.style.top);
    bar.on_drag_start(bar.startX, bar.startY);
    dw_event.add( document, "mousemove", dw_slidebar.doDrag, true );
    dw_event.add( document, "mouseup",   dw_slidebar.endDrag,  true );
    e.stopPropagation();
  },

  doDrag: function (e) {
    e = e? e: window.event;
    if (!dw_slidebar.obj) return;
    var bar = dw_slidebar.obj; 
    var nx = bar.startX + e.clientX - bar.downX;
    var ny = bar.startY + e.clientY - bar.downY;
    nx = Math.min( Math.max( bar.minX, nx ), bar.maxX);
    ny = Math.min( Math.max( bar.minY, ny ), bar.maxY);
    bar.style.left = nx + "px"; bar.style.top  = ny + "px";
    bar.on_drag(nx,ny);
    return false;  
  },
  
  endDrag: function () {
    dw_event.remove( document, "mousemove", dw_slidebar.doDrag, true );
    dw_event.remove( document, "mouseup",   dw_slidebar.endDrag,  true );
    if ( !dw_slidebar.obj ) return; // avoid errors in ie if inappropriate selections
    dw_slidebar.obj.on_drag_end( parseInt(dw_slidebar.obj.style.left), parseInt(dw_slidebar.obj.style.top) );
    dw_slidebar.obj = null;  
  }
  
}