/******************************************************************************
* scroller.js                                                                 *
*                                                                             *
* Copyright 1999 by Mike Hall.                                                *
* Web address: http://www.brainjar.com                                        *
* Last update: December 1, 1999.                                              *
*                                                                             *
* Allows you to create scrolling displays on a page. Multiple scrollers can   *
* be defined, each with it's own parameters and list of items. Item text can  *
* include basic HTML tags, including links and images.                        *
* Note: requires dhtmllib.js.                                                 *
******************************************************************************/

//*****************************************************************************
// Scroller constructor.
//*****************************************************************************

var _SUBHEAD = 1<<0 ;
var _SOURCE  = 1<<1 ;
var _BYLINE  = 1<<2 ;
var _PAGE    = 1<<3 ;
var _DATE    = 1<<4 ;
var _YEAR    = 1<<5 ;
var _TIME    = 1<<6 ;
var _SUBHEAD_AS_BLURB = 1<<7 ;
var _SOURCE_AND_DATE = _SOURCE+_DATE+_YEAR+_TIME ;
var _BYLINE_AND_PAGE = _SUBHEAD+_BYLINE+_PAGE ;

function Scroller(x, y, width, height, border, padding)
{
  this.x = x;
  this.y = y;
  this.width = width;
  this.height = height;
  this.border = border;
  this.padding = padding;

  this.items = new Array();
  this.id = new Array();
  this.time = new Array();
  this.created = false;

  // Set default colors.
  this.fgColor = "";
  this.bgColor = "";
  this.bdColor = "";

  // Set default font.
  this.fontFace = "Arial,Helvetica";
  this.fontSize = "2";

  // Set default scroll timing values.
  this.speed = 100;
  this.pauseTime = 4000;

  // Define other properties
  this.layerName = "placeholder";
  this.linkHeadlines = true ;
  this.headlineUrl = null ;
  
  // Define methods.
  this.setColors = scrollerSetColors;
  this.setFont = scrollerSetFont;
  this.setSpeed = scrollerSetSpeed;
  this.setPause = scrollersetPause;
  this.setLayerName = scrollersetLayerName;
  this.getLayerName = scrollergetLayerName;
  this.setHeadlineUrl = scrollersetHeadlineUrl;
  this.getHeadlineUrl = scrollergetHeadlineUrl;
  this.addItem = scrollerAddItem;
  this.addHeadlinesAsItems = scrollerAddHeadlinesAsItems;
  this.create = scrollerCreate;
  this.show = scrollerShow;
  this.hide = scrollerHide;
  this.moveTo = scrollerMoveTo;
  this.moveBy = scrollerMoveBy;
  this.getzIndex = scrollerGetzIndex;
  this.setzIndex = scrollerSetzIndex;
  this.stop = scrollerStop;
  this.start = scrollerStart;
}

//*****************************************************************************
// Scroller methods.
//*****************************************************************************

function scrollerSetColors(fgcolor, bgcolor, bdcolor) {

  if (this.created) {
    
    return;
  }
  this.fgColor = fgcolor;
  this.bgColor = bgcolor;
  this.bdColor = bdcolor;
}

function scrollerSetFont(face, size) {

  if (this.created) {
    
    return;
  }
  this.fontFace = face;
  this.fontSize = size;
}

function scrollerSetSpeed(pps) {

  if (this.created) {
    
    return;
  }
  this.speed = pps;
}

function scrollersetPause(ms) {
  if (this.created) {
    return;
  }
  this.pauseTime = ms;
}

function scrollersetLayerName(name) {
  if (this.created) {
    return;
  }
  this.layerName = name;
}

function scrollergetLayerName() {
  return this.layerName ;
}

function scrollersetHeadlineUrl(url) {
  if (this.created) {
    return;
  }
  this.headlineUrl = url;
}

function scrollergetHeadlineUrl(){
  return this.headlineUrl ;
}

function scrollerAddItem(str) {

  if (this.created) {
    
    return;
  }
  this.items[this.items.length] = str;
}

function scrollerAddHeadlinesAsItems(headlines,length,code)
{

  // private function for removing characters (contained in an array) from a string
  function removeChars(str,ch)
  {
    var buffer = '' ;
    var a = new Array() ;
	
	for (var i=0;i<ch.length;i++)
	{
      a = str.split(ch[i]) ;
	  for (var j=0;j<a.length;j++)
	  {
	    buffer += a[j] ;
	  }
	  str = buffer ;
	  buffer = '' ;
	}

    return str ;
  }

  function trim(str)
  {
    while ( str.charAt(0) == ' ' || str.charAt(0) == '	' )
	  str = str.substr(1) ;
    while ( str.charAt(str.length-1) == ' ' || str.charAt(str.length-1) == '	' )
	  str = str.substr(0,str.length-1) ;
	return str ;
  }

  if ( typeof length == 'undefined' || length > headlines.length )
    length = headlines.length ;
	
  if ( typeof code == 'undefined' )
    code = 0 ;

  var DELIMITER = '|' ;
  var chars1 = new Array('(',')') ;

  for (var count = 0; count < length; count++)
  {
    var info = new Array() ;
	info = headlines[count].split(DELIMITER) ;
	var fullHeadline = info[0] ;
	var headline = new Array() ;
	headline = fullHeadline.split("</B>") ;
	var shortHeadline = headline[0]+"</B>" ;
	var subHeadline   = headline[1] ;
	subHeadline = subHeadline.substr(subHeadline.indexOf(": ")+2) ;
	var id            = info[1] ;

	// (washingtonpost.com, March 18, 2003; 6:17 PM), (Post, March 18, 2003)
	var details1 = info[2] ;
	if ( details1 )
	{
      details1 = removeChars(details1,chars1) ;
	  var source = details1.substr(0,details1.indexOf(',')) ;
	  var dateyeartime = details1.substr(details1.indexOf(',')+1) ;
	  var dyt = new Array() ;
	  dyt = dateyeartime.split('; ') ;
	  var dateyear = dyt[0] ;
	  var time = dyt[1] ;
	  dyt = dateyear.split(', ') ;
	  var date = dyt[0] ;
	  var year = dyt[1] ;
	}

	// (By Jabari Asim, Page C02 ), (By Jabari Asim)
	var details2 = info[3] ;
	if ( details2 )
	{
      details2 = removeChars(details2,chars1) ;  
	  var bs = new Array() ;
	  bs = details2.split(', ') ;
	  var byline = bs[0] ;
	  var page = bs[1] ;
	  if ( byline && byline.indexOf('Page ') == 0 )
	  {
		page = byline ;
		byline = null ;
	  }
	}

	// available for display or use
	// id, shortHeadline, source, and date probably won't be null. Check the others for sure.
	// id,shortHeadline,subHeadline,source,byline,page,date,year,time

	if ( this.headlineUrl )
	  var hUrl = this.headlineUrl ;
	else
	  var hUrl = id ;

	var printHeadlineItem = '' ;
	if ( this.linkHeadlines )
	  printHeadlineItem += '<A HREF="'+hUrl+'">' ;
	
	printHeadlineItem += trim(shortHeadline) ;
    // _SUBHEAD
	if ( (code&_SUBHEAD) && subHeadline )
	  printHeadlineItem += '<b>:</b> '+trim(subHeadline) ;
	
	if ( this.linkHeadlines )
      printHeadlineItem += '</A>' ;

    // _SUBHEAD_AS_BLURB
	if ( (code&_SUBHEAD_AS_BLURB) && subHeadline )
	  printHeadlineItem += '<br>'+trim(subHeadline) ;
	
    var first = true ;
	var prefix = '' ;
	var more = '' 
	if ( code )
	{
      // stuff goes into parenthesis
	  if ( code != _SUBHEAD )
	    more += ' <i>(' ;

	  // _SOURCE
      if ( (code&_SOURCE) && source  )
	  {
	    prefix = first ? '' : ', ' ;
	    more += prefix+trim(source) ;
		first = false ;
	  }

	  // _BYLINE
	  if ( (code&_BYLINE) && byline )
	  {
	    prefix = first ? '' : ', ' ;
	    more += prefix+trim(byline) ;
		first = false ;
	  }

	  // _PAGE
	  if ( (code&_PAGE) && page )
	  {
	    prefix = first ? '' : ', ' ;
	    more += prefix+trim(page) ;
		first = false ;
	  }

	  // _DATE
	  if ( (code&_DATE) && date )
	  {
	    prefix = first ? '' : ', ' ;
	    more += prefix+trim(date) ;
		first = false ;
	  }

	  // _YEAR
	  if ( (code&_YEAR) && year )
	  {
	    prefix = first ? '' : ', ' ;
	    more += prefix+trim(year) ;
		first = false ;
	  }

	  // _TIME
	  if ( (code&_TIME) && time )
	  {
	    prefix = first ? '' : '; ' ;
		more += prefix+trim(time) ;
		first = false ;
	  }

      // stuff goes into parenthesis
	  if ( code != _SUBHEAD )
	    more += ')</i>' ;

	  // remove parens if everything was null or only time was displayed
	  if ( first || code == _TIME )
	    more = removeChars(more,chars1) ;
	}
	
    printHeadlineItem += more ;
    this.addItem(printHeadlineItem);
  }
}

function scrollerCreate() {

  var start, end;
  var str;
  var i, j;
  var x, y;

  if (!isMinNS4 && !isMinIE4)
    return;

  // On first scroller, start interval timer.

  if (scrollerList.length == 0)
    setInterval('scrollerGo()', scrollerInterval);

  // Create the scroller only once.

  if (this.created) {
    
    return;
  }
  this.created = true;

  // Copy first item to the end of the list, this lets us scroll from the last
  // defined item to the first without jumping.

  this.items[this.items.length] = this.items[0];

  // Set up HTML code for item text.

  start = '<table border=0'
        + ' cellpadding=' + (this.padding + this.border)
        + ' cellspacing=0'
        + ' width=' + this.width
        + ' height=' + this.height + '>'
        + '<tr><td>'
        + '<font'
        + ' color="' + this.fgColor + '"'
        + ' face="' + this.fontFace + '"'
        + ' size=' + this.fontSize + '>';
  end   = '</font></td></tr></table>';

  // Build the layers.

  if (isMinNS4) {
    this.baseLayer = new Layer(this.width);
    this.scrollLayer = new Layer(this.width, this.baseLayer);
    this.scrollLayer.visibility = "inherit";
    this.itemLayers = new Array();
    for (i = 0; i < this.items.length; i++) {
      this.itemLayers[i] = new Layer(this.width, this.scrollLayer);
      this.itemLayers[i].document.open();
      this.itemLayers[i].document.writeln(start + this.items[i] + end);
      this.itemLayers[i].document.close();
      this.itemLayers[i].visibility = "inherit";
    }

    // Set background colors.

    setBgColor(this.baseLayer, this.bdColor);
    setBgColor(this.scrollLayer, this.bgColor);
  }

  if (isMinIE4) {
    i = scrollerList.length;
    str = '<div id="scroller' + i + '_baseLayer"'
        + ' style="position:absolute;'
        + ' background-color:' + this.bdColor + ';'
        + ' width:' + this.width + 'px;'
        + ' height:' + this.height + 'px;'
        + ' overflow:hidden;'
        + ' visibility:hidden;">\n'
        + '<div id="scroller' + i + '_scrollLayer"'
        + ' style="position:absolute;'
        + ' background-color: ' + this.bgColor + ';'
        + ' width:' + this.width + 'px;'
        + ' height:' + (this.height * this.items.length) + 'px;'
        + ' visibility:inherit;">\n';
    for (j = 0; j < this.items.length; j++) {
      str += '<div id="scroller' + i + '_itemLayers' + j + '"'
          +  ' style="position:absolute;'
          +  ' width:' + this.width + 'px;'
          +  ' height:' + this.height + 'px;'
          +  ' visibility:inherit;">\n'
          +  start + this.items[j] + end
          +  '</div>\n';
    }
    str += '</div>\n'
        +  '</div>\n';

    // Insert HTML code at end of page. For IE4, need to scroll window to
    // end of page, insert and scroll back to correct bug.

    if (!isMinIE5) {
      x = getPageScrollX();
      y = getPageScrollY();
      window.scrollTo(getPageWidth(), getPageHeight());
    }
    document.body.insertAdjacentHTML("beforeEnd", str);
    if (!isMinIE5)
      window.scrollTo(x, y);

    // Get handles to each layer.

    this.baseLayer = getLayer("scroller" + i + "_baseLayer");
    this.scrollLayer = getLayer("scroller" + i + "_scrollLayer");
    this.itemLayers = new Array();
    for (j = 0; j < this.items.length; j++)
      this.itemLayers[j] = getLayer("scroller" + i + "_itemLayers" + j);
  }

  // Position and clip base and scroll layers.

  moveLayerTo(this.baseLayer, this.x, this.y);
  clipLayer(this.baseLayer, 0, 0, this.width, this.height);
  moveLayerTo(this.scrollLayer, this.border, this.border);
  clipLayer(this.scrollLayer, 0, 0,
            this.width - 2 * this.border, this.height - 2 * this.border);

  // Position and clip each item layer.

  x = 0;
  y = 0;
  for (i = 0; i < this.items.length; i++) {
    moveLayerTo(this.itemLayers[i], x, y);
    clipLayer(this.itemLayers[i], 0, 0, this.width, this.height);
    y += this.height;
  }

  // Set up scrolling parameters.

  this.stopped = false;
  this.currentY = 0;
  this.stepY = this.speed / (1000 / scrollerInterval);
  this.stepY = Math.min(this.height, this.stepY);
  this.nextY = this.height;
  this.maxY = this.height * (this.items.length - 1);
  this.paused = true;
  this.counter = 0;

  // Add to global list.

  scrollerList[scrollerList.length] = this;

  // Display it.

  showLayer(this.baseLayer);
}

function scrollerShow() {

  if (this.created)
    showLayer(this.baseLayer);
}

function scrollerHide() {

  if (this.created)
    hideLayer(this.baseLayer);
}

function scrollerMoveTo(x, y) {

  if (this.created)
    moveLayerTo(this.baseLayer, x, y);
}

function scrollerMoveBy(dx, dy) {

  if (this.created)
    moveLayerBy(this.baseLayer, dx, dy);
}

function scrollerGetzIndex() {

  if (this.created)
    return(getzIndex(this.baseLayer));
  else
    return(0);
}

function scrollerSetzIndex(z) {

  if (this.created)
    setzIndex(this.baseLayer, z);
}

function scrollerStart() {

  this.stopped = false;
}

function scrollerStop() {

  this.stopped = true;
}

//*****************************************************************************
// Code for scrolling.
//*****************************************************************************

// An array is used to hold a pointer to each scroller that is defined. The
// scrollerGo() function runs at regular intervals and updates each scroller
// in this list.

var scrollerList     = new Array();
var scrollerInterval = 20;

function scrollerGo() {

  var i;

  // Update each scroller object in the list.

  for (i = 0; i < scrollerList.length; i++) {

    // If stopped, skip.

    if (scrollerList[i].stopped);

    // If paused, update counter.

    else if (scrollerList[i].paused) {
      scrollerList[i].counter += scrollerInterval;
      if (scrollerList[i].counter > scrollerList[i].pauseTime)
        scrollerList[i].paused = false;
    }

    // Scroll it.

    else {
      scrollerList[i].currentY += scrollerList[i].stepY;

      // Pause it if the next item has scrolled into view.

      if (scrollerList[i].currentY >= scrollerList[i].nextY) {
        scrollerList[i].paused = true;
        scrollerList[i].counter = 0;
        scrollerList[i].currentY = scrollerList[i].nextY;
        scrollerList[i].nextY += scrollerList[i].height;
      }

      // When we reach the end, start over.

      if (scrollerList[i].currentY >= scrollerList[i].maxY) {
        scrollerList[i].currentY -= scrollerList[i].maxY;
        scrollerList[i].nextY = scrollerList[i].height;
      }
      scrollLayerTo(scrollerList[i].scrollLayer,
                    0, Math.round(scrollerList[i].currentY),
                    false);
    }
  }
}

//*****************************************************************************
// Code to handle a window resize.
//*****************************************************************************

// These variables are used to determine if a resize event is a true one.
// Necessary due to a bug in older NS4 releases.

var origWidth;
var origHeight;

// Fix for resize bug.

if (isMinNS4) {
  origWidth  = window.innerWidth;
  origHeight = window.innerHeight;
}
window.onresize = scrollerReload;

function scrollerReload() {

  // Reload page in case of a browser resize. First make sure it's a true
  // resize.

  if (isMinNS4 && origWidth == window.innerWidth && origHeight == window.innerHeight) {
    return;
  window.location.href = window.location.href;
  }
}