//// toggler.js - control various twisty controls

// performed when the page loads
// if there is no cookie yet set initial settings in togglerInitializeSettings
// because arrows don't show if no cookie to avoid showing them for no-JS mode
// show the "print this link" link if JS is on

function togglerInitialSettings() {
  var eltinfo = twistyRead();
  if (!eltinfo.cnx_course_navigation) togglerInitializeSettings('cnx_course_navigation');
  if (!eltinfo.cnx_recentview) togglerInitializeSettings('cnx_recentview');
  if (!eltinfo.cnx_author_links) togglerInitializeSettings('cnx_author_links');

  if (readCookie('cnx_javascript_present') == null) {
    createCookie('cnx_javascript_present', 'true', 365);
    hideSolutions();
  }
}


// if user doesn't have a cookie set yet, set elements as follows:
// - collection table of contents is shown
// - author links are shown
// - expandable content actions areas are hidden
// these also override the default (hardcoded) settings for non-JS users which are:
// - togglers ("show/hide" links) are not shown
// - expandable content actions areas are shown

function togglerInitializeSettings(id) {
  var eltcontents = document.getElementById(id + '_contents');
  // errors will result if we refer to this element when it doesn't exist,
  // as may be the case for collection-only elements
  if (eltcontents) {
    if (id == 'cnx_course_navigation') {
      document.getElementById(id + '_expand').style.display = 'none';
      document.getElementById(id + '_collapse').style.display = 'inline';
      eltcontents.style.display = 'block';
    } else if (id == 'cnx_recentview') {
      document.getElementById(id + '_expand').style.display = 'inline';
      document.getElementById(id + '_collapse').style.display = 'none';
      eltcontents.style.display = 'none';
    } else if (id == 'cnx_author_links') {
      document.getElementById(id + '_togglers').style.display = 'block';
      document.getElementById(id + '_expand').style.display = 'none';
      document.getElementById(id + '_collapse').style.display = 'block';
      eltcontents.style.display = 'block';
    }
    else {
      document.getElementById(id + '_link').style.backgroundImage = 'url(' + stylesheetloc + 'arrow-closed.png)';
      document.getElementById(id + '_contents').style.display = 'none';
    }
    twistyWrite(id, eltcontents.style.display);
  }
}


// specialized toggler for use in the "Content Actions" box
// see also 'twist_toggle()' in RhaptosSite's rhaptosutils.js

function togglerCA(id) {
  var contents = document.getElementById(id + '_contents').style;
  var link = document.getElementById(id + '_link').style;
  if (contents.display == 'none') {
    contents.display = 'block';
    link.backgroundImage = 'url(' + stylesheetloc + 'arrow-open.png)';
  } else {
    contents.display = 'none';
    link.backgroundImage = 'url(' + stylesheetloc + 'arrow-closed.png)';
  }
  twistyWrite(id, contents.display);
}




// for getting the location of the stylesheet currently in use, so that we can refer to images in that style's folder

var stylesheetloc = getPreferredStyleSheet().split('document.css')[0];

function getPreferredStyleSheet() {
  var i, a;
  for(i=0; (a = document.getElementsByTagName("link")[i]); i++) {
    if(a.getAttribute("rel").indexOf("style") != -1
       && a.getAttribute("rel").indexOf("alt") == -1
       && a.getAttribute("title")
       ) return a.getAttribute("href");
  }
  return null;
}

function hideSolutions(){
  var x = getElementsByClassName('solution');
  for (var i = 0; i < x.length; i++) {  
    x[i].style.display = 'none';    
  }
  var y = getElementsByClassName('solution-toggles');
  for (var i = 0; i < y.length; i++) {
    y[i].style.display = 'block';
  }
}

function getFirefoxVersion()
{
	var version;
	var verStart = navigator.userAgent.indexOf("Firefox") + "Firefox/".length;
    var ver = navigator.userAgent.substring(verStart).split(".");
    if(!ver || ver.length == 1) 
    { 
    	version = 0; 
    }
    else if (ver.length == 2) 
    { 
    	version = parseFloat(ver[0]+".0"); 
    }
    else 
    { 
    	version = parseFloat(ver[0]+"."+ver[1]); 
    }
    return version;
	
}


function toggleLensTags(sender)
{
    // Expand / collapse first sibling div of sender
    var parent = sender.parentNode;
    var div = parent.getElementsByTagName('div')[0];
    var closed = sender.getElementsByTagName('img')[0];
    var open = sender.getElementsByTagName('img')[1];
    if(div.style.display == 'block'){
        div.style.display = 'none'
        closed.style.display = 'inline';
        open.style.display = 'none';
    } else {
        div.style.display = 'block'
        closed.style.display = 'none';
        open.style.display = 'inline';
    }
}

//// Ratings Stars ////

function previewRating(value, number_of_stars, can_rate, prefix)
{
    if (!prefix) {
        prefix = "content-render-";
    }

    // Toggle src on images to achieve highlight effect
    for (var i=1; i<=number_of_stars; i++)
    {
        var img = document.getElementById(prefix + 'rating-star'+i);
        var div = document.getElementById(prefix + 'rating-exp'+i);

        if (i <= value)        
            img.src = '/full_star.png';
        else
            img.src = '/empty_star.png';

        if (i == value)
            div.style.display = 'inline';
        else
            div.style.display = 'none';
    }
    if (!can_rate)
    {
        document.getElementById(prefix + 'rating-ratings').style.display = 'none';
        document.getElementById(prefix + 'rating-login').style.display = 'inline';
    }
}

function clearRatings(number_of_stars, prefix)
{
    if (!prefix) {
        prefix = "content-render-";
    }

    // Restore src on images to remove highlight effect
    for (var i=1; i<=number_of_stars; i++)
    {
        var img = document.getElementById(prefix + 'rating-star'+i);
        var div = document.getElementById(prefix + 'rating-exp'+i);
        img.src = img.getAttribute('original_src');
        div.style.display = 'none';
    }
    document.getElementById(prefix + 'rating-ratings').style.display = 'inline';
    document.getElementById(prefix + 'rating-login').style.display = 'none';
}