--- rat/lonwrapper.pm	2019/05/02 02:12:31	1.69
+++ rat/lonwrapper.pm	2020/02/29 16:05:26	1.76
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Wrapper for external and binary files as standalone resources
 #
-# $Id: lonwrapper.pm,v 1.69 2019/05/02 02:12:31 raeburn Exp $
+# $Id: lonwrapper.pm,v 1.76 2020/02/29 16:05:26 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -89,7 +89,7 @@ sub wrapper {
         $args->{'only_body'} = $env{'form.only_body'};
     }
 
-    my ($countdown,$donemsg);
+    my ($countdown,$donemsg,$headjs);
     if (($exttool) && (&Apache::lonnet::EXT('resource.0.gradable') =~ /^yes$/i)) {
         $Apache::lonhomework::browse = &Apache::lonnet::allowed('bre',$url);
         if ($env{'form.markaccess'}) {
@@ -135,7 +135,24 @@ sub wrapper {
         }
     }
 
-    my $startpage = &Apache::loncommon::start_page('Menu',undef,$args).$countdown.$donemsg;
+#
+# Where iframe is in use, if window.onload() executes before the custom resize function
+# has been defined (jQuery), two global javascript vars (LCnotready and LCresizedef)
+# are used to ensure document.ready() triggers a call to resize, so the iframe contents
+# do not obscure the Functions menu.
+#
+
+    unless (($env{'browser.mobile'}) || ($exttool eq 'window') || ($exttool eq 'tab') || $uselink) {
+        $headjs = '
+<script type="text/javascript">
+// <![CDATA[
+var LCnotready = 0;
+var LCresizedef = 0;
+// ]]>
+</script>'."\n";
+    }
+
+    my $startpage = &Apache::loncommon::start_page('Menu',$headjs,$args).$countdown.$donemsg;
     my $endpage = &Apache::loncommon::end_page();
 
     if (($uselink) && ($title eq '')) {
@@ -167,9 +184,9 @@ sub wrapper {
                 $output .= <<"ENDLINK";
 <script type="text/javascript">
 // <![CDATA[
-var windowObjectReference = null; 
-var PreviousUrl; 
-                           
+var windowObjectReference = null;
+var PreviousUrl;
+
 function openSinglePopup(strUrl) {
     if (windowObjectReference == null || windowObjectReference.closed) {
         windowObjectReference = window.open(strUrl, "LCExternalToolPopUp",
@@ -243,8 +260,20 @@ ENDLINK
                 var pos = height + hdrtop + offset;
                 \$('.LC_iframecontainer').css('top', pos);
             });
+            LCresizedef = 1;
+            if (LCnotready == 1) {
+                LCnotready = 0;
+                \$(window).trigger('resize');
+            }
         });
-        window.onload = function(){  \$(window).trigger('resize') };
+        window.onload = function(){
+             if (LCresizedef) {
+                 LCnotready = 0;
+                 \$(window).trigger('resize');
+             } else {
+                 LCnotready = 1;
+             }
+        };
 SCRIPT
         # javascript will position the iframe if window was resized (or zoomed)
         my $dest = &HTML::Entities::encode($url.$anchor,'&<>"');
@@ -292,9 +321,9 @@ sub handler {
 
     for ($url){
         s|^/adm/wrapper||;
-        $is_ext = $_ =~ s|^/ext/|http://|;         
-        s|http://https://|https://|;
-        s|&colon;|:|g;              
+        $is_ext = $_ =~ s|^/ext/|http://|;
+        s|http://https://|https://| if ($is_ext);
+        s|&colon;|:|g;
     }
 
     if ($url =~ /\.pdf$/i) {
@@ -318,10 +347,10 @@ sub handler {
             $width = $toolhash{'width'};
             $height = $toolhash{'height'};
         } elsif ($toolhash{'target'} eq 'tab') {
-            $exttool = 'tab'; 
+            $exttool = 'tab';
         }
         if (($exttool eq 'window') || ($exttool eq 'tab')) {
-            $linktext = $toolhash{'linktext'}; 
+            $linktext = $toolhash{'linktext'};
             $explanation = $toolhash{'explanation'};
         } elsif (($exttoolremote =~ /^http:/) && ($ENV{'SERVER_PORT'} == 443)) {
             $exttool = 'tab';
@@ -427,7 +456,7 @@ described at http://www.lon-capa.org.
 
 =over
 
-=item wrapper($r,$url,$brcrum,$absolute,$is_ext,$is_pdf,$linktext,$explanation,$title,$width,$height)
+=item wrapper($r,$url,$brcrum,$absolute,$is_ext,$is_pdf,$exttool,$linktext,$explanation,$title,$width,$height)
 
 =over
 
@@ -437,8 +466,11 @@ request object
 
 =item $url
 
-url to display by including in an iframe within a
-LON-CAPA page which has a standard LON-CAPA inline menu.
+url to display either by including in an iframe within a
+LON-CAPA page which has a standard LON-CAPA inline menu,
+or in some cases launched in a separate tab or window,
+launched via a link in a LON-CAPA page with standard inline
+menu.
 
 =item $brcrum
 
@@ -473,6 +505,22 @@ true if URL is for an external resource.
 
 true if URL is for a PDF (based on file extension).
 
+=item $exttool
+
+If URL is for an External Tool, will contain the target type: iframe, window or tab.
+
+=item $linktext
+
+optional. If URL is for an External Tool, and target type is window or tab, 
+then the link text may be an option set in the course for each tool instance,
+or may be a default defined in the domain for all instances of the tool.
+
+=item $explanation
+
+optional. If URL is for an External Tool, and target type is window or tab, 
+then the explanation is an option set in the course for each tool instance,
+or may be a default defined in the domain for all instances of the tool.
+
 =item $title
 
 optional. If wrapped item is a PDF, and $env{'browser.mobile'} 
@@ -481,12 +529,45 @@ above the link, but if not provided as a
 will be used, otherwise, the filename will be displayed (unless
 hidden URL set for the resource).
 
+=item $width
+
+optional. If URL is for an External Tool, and target type is window,
+then a default width may have been defined in the domain for all instances of 
+the tool.  If so, that width will be used for the window opened (via a link)
+to launch the external tool.
+
+=item $height
+
+optional. If URL is for an External Tool, and target type is window,
+then a default height may have been defined in the domain for all instances of 
+the tool.  If so, that height will be used for the window opened (via a link)
+to launch the external tool.
+
 =back
 
 Returns markup for the entire page.
 
 =item handler()
 
+Content handler for requests for: /adm/wrapper/...
+used for content to be displayed in an iframe, or launched in a separate tab
+or window via a link.  The target URL is extracted from the requested URL, by
+removing the /adm/wrapper prefix. 
+
+The target URL will typically be a PDF served from the current server, an 
+external resource URL served from a different server, or an external tool
+(from an LTI Provider) launched from LON-CAPA (as LTI Consumer) and launched
+via a link.
+
+If the request included forceedit in the query string, and the requester has
+rights to modify course content, then the editor will be didplayed to allow
+changes to be made to the resource (e.g., change the URL of the external resource,
+or change the setting for the external tool instance.
+
+If not in edit mode, then the wrapper() subroutine will be called to generate the
+standard LON-CAPA inline menu, and then either a link to launch a separate tab or
+window, or an iframe to display the content inline. 
+
 =back
 
 =cut