--- loncom/interface/lonhtmlcommon.pm	2012/03/20 13:36:19	1.303
+++ loncom/interface/lonhtmlcommon.pm	2012/04/05 15:56:13	1.308
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # a pile of common html routines
 #
-# $Id: lonhtmlcommon.pm,v 1.303 2012/03/20 13:36:19 www Exp $
+# $Id: lonhtmlcommon.pm,v 1.308 2012/04/05 15:56:13 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -1111,6 +1111,7 @@ sub crumbs {
     if ($uri !~ m|/$|) { $output=~s|/$||; }
     $output.='</span>';
 
+
     return $output;
 }
 
@@ -1175,6 +1176,8 @@ ENDEDITOR
 <script type="text/javascript" src="/adm/jpicker/js/jpicker-1.1.6.min.js" >
 </script>
 <link rel="stylesheet" type="text/css" href="/adm/jpicker/css/jPicker-1.1.6.min.css" />
+<script type='text/javascript' src='/adm/countdown/js/jquery.countdown.js'></script>
+<link rel="stylesheet" type="text/css" src='/adm/countdown/css/jquery.countdown.css' />
 ENDJQUERY
 	return $s;
 }
@@ -1306,8 +1309,55 @@ sub htmlareaselectactive {
                 $.fn.jPicker.defaults.images.clientPath="/adm/jpicker/images/";
                 $(".colorchooser").jPicker();
 
+
 	});
 ';
+    # Code to put a due date countdown in 'duedatecountdown' span.
+    # This is currently located in the breadcrumb headers.
+    # note that the dueDateLayout is internatinoalized below.
+    # Here document is used to support the substitution into the javascript below.
+    # ..which unforunately necessitates escaping the $'s in the javascript.
+    # There are several times of importance
+    #
+    # serverDueDate -  The absolute time at which the problem expires.
+    # serverTime    -  The server's time when the problem finished computing.
+    # clientTime    -  The client's time...as close to serverTime as possible.
+    #                  The clientTime will be slightly later due to
+    #                  1. The latency between problem computation and 
+    #                     the first network action.
+    #                  2. The time required between the page load-start and the actual
+    #                     initial javascript execution that got clientTime.
+    # These are used as follows:
+    #   The difference between clientTime and serverTime are used to 
+    #   correct for differences in clock settings between the browser's system and the
+    #   server's.
+    #
+    #   The difference between clientTime and the time at which the ready() method
+    #   starts executing is used to estimate latencies for page load and submission.
+    #   Since this is an estimate, it is doubled.  The latency estimate + one minute
+    #   is used to determine when the countdown timer turns red to warn the user
+    #   to think about submitting.
+
+    my $dueDateLayout = '<b>' .  &mt('Due in: {dn} {dl} {hnn}{sep}{mnn}{sep}{snn} - Submit early!') . '</b>';
+    $output .= <<JAVASCRIPT;
+
+    var documentReadyTime;
+
+\$(document).ready(function() {
+   if (typeof(dueDate) != "undefined") {
+       documentReadyTime = (new Date()).getTime();
+      \$("#duedatecountdown").countdown({until: dueDate, compact: true, 
+         layout: "$dueDateLayout",
+         onTick: function (periods) {
+	    var latencyEstimate = (documentReadyTime - clientTime) * 2;
+            if(\$.countdown.periodsToSeconds(periods) < (60 + latencyEstimate)) {
+               \$(this).css("color", "red");   //Highlight last minute.
+            }
+         }
+      });
+   }
+});
+JAVASCRIPT
     if ($dragmath_prefix ne '') {
         $output .= '
 
@@ -1383,6 +1433,62 @@ sub show_return_link {
 }
 
 
+##
+#   Set the dueDate variable...note this is done in the timezone
+#   of the browser.
+#
+# @param epoch relative time at which the problem is due.
+#
+# @return the javascript fragment to set the date:
+#
+sub set_due_date {
+    my $dueStamp = shift;
+    my $duems    = $dueStamp * 1000; # Javascript Date object needs ms not seconds.
+
+    my $now = time()*1000;
+
+    # This slightly obscure bit of javascript sets the dueDate variable
+    # to the time in the browser at which the problem was due.  
+    # The code should correct for gross differences between the server
+    # and client's time setting
+
+    my $js = "
+<script type='text/javascript'>
+  //<![CDATA[
+var serverDueDate = $duems;
+var serverTime    = $now;
+var clientTime    = (new Date()).getTime();
+var dueDate       = new Date(serverDueDate + (clientTime - serverTime));
+
+  //]]>
+</script>
+";
+
+    return $js;
+}
+##
+# Sets the time at which the problem finished computing.
+# This just updates the serverTime and clientTime variables above.
+# Calling this in e.g. end_problem provides a better estimate of the
+# difference beetween the server and client time setting as 
+# the difference contains less of the latency/problem compute time.
+#
+sub set_compute_end_time {
+
+    my $now = time()*1000;	# Javascript times are in ms.
+    my $js = "
+<script type='text/javascript'>
+//<![CDATA[
+serverTime = $now;
+clientTime = (new Date()).getTime();
+//]]>
+</script>
+
+";
+    return $js;
+    
+}
+
 ############################################################
 ############################################################
 
@@ -1501,9 +1607,12 @@ returns: nothing
 
         # last breadcrumb is the first order heading of a page
         # for course breadcrumbs it's just bold
+
         $links .= &htmltag( 'li', htmltag($CourseBreadcrumbs ? 'b' : 'h1',
                 $lasttext), {title => $lasttext});
 
+	$links .=   '<li> <span id="duedatecountdown"></span></li>'; 
+
         my $icons = '';
         $faq  = $last->{'faq'}  if (exists($last->{'faq'}));
         $bug  = $last->{'bug'}  if (exists($last->{'bug'}));
@@ -1521,6 +1630,7 @@ returns: nothing
                                                          $faq,$bug);
         }
         #
+
 		
 
         unless ($CourseBreadcrumbs) {
@@ -1529,12 +1639,14 @@ returns: nothing
             $links = &htmltag('ul',  $links, { class => "LC_CourseBreadcrumbs" });
         }
 
+
         if ($component) {
             $links = &htmltag('span', 
                              ( $no_mt ? $component : mt($component) ).
                              ( $icons ? $icons : '' ),
                              { class => 'LC_breadcrumbs_component' } )
-                             .$links;
+                             .$links 
+;
         }
         
         &render_tools(\$links);
@@ -1545,7 +1657,12 @@ returns: nothing
         # Return the @Crumbs stack to what we started with
         push(@Crumbs,$last);
         shift(@Crumbs);
+
+
         # Return the breadcrumb's line
+
+    
+
         return "$links";
     }
 
@@ -2738,7 +2855,8 @@ sub generate_menu {
                                 $$link{alttext} : $$link{linktext})
                             }), {
                             href  => $$link{url},
-                            title => mt($$link{linktitle})
+                            title => mt($$link{linktitle}),
+                            class => 'LC_menubuttons_link'
                             }).
                         $a->(mt($$link{linktext}), {
                             href  => $$link{url},