====== Display ACLs in page footer ======

Sometimes, it is interesting to know, who is allowed to view the current page. Checking this in the ACL plugin is difficult and only possible for admins. By patching your favorite [[:Template|template]], you can display this information in the page footer. Remarks, suggestions etc. go to <bihler@iai.uni-bonn.de>.

===== Instructions =====
 
Somewhere in your template's ''main.php'', you'll find these lines (line 101-108 in the default template):

<code php>
    <div class="meta">
      <div class="user">
        <?php tpl_userinfo()?>
      </div>
      <div class="doc">
        <?php tpl_pageinfo()?>
      </div>
    </div>
</code>

Replace these lines with the following code:

<code php>
   <?php
    function tpl_aclinfo() {
	global $ID, $AUTH_ACL;
	
	if (auth_quickaclcheck($ID) == 0) 
	    return; // no rights to view, no rights to get this info
	
	$page_acls = array();
	$namespaces = array();
    
	$ns = getNS($ID);
	while ($ns) {
	   array_unshift($namespaces,$ns . ':*');
	   $ns = getNS($ns);  
	}
	array_unshift($namespaces,'*'); // root
       
	$namespaces[] = $ID;
       
	// check matches
	foreach ($namespaces as $level) {
		$matches = preg_grep('/^'.preg_quote($level,'/').'\s+\S+\s+\d+\s*$/',$AUTH_ACL);
	    $this_acls = array();
		foreach($matches as $match){
	      $match = preg_replace('/#.*$/','',$match); //ignore comments
	      $acl   = preg_split('/\s+/',$match);
	      $this_acls[urldecode($acl[1])] = $acl[2];
	      if ($acl[1] == "@ALL")  // overwrites stuff from upper level
	        $page_acls = array();
	    }
	    $page_acls =  array_merge($page_acls,$this_acls);
	}
    
	// check if visible to everyone:
	if (($page_acls['@ALL'] !== false) && $page_acls['@ALL'] > 0) 
	  return; // page is visible to everyone
    
	$list = array();	
	foreach ($page_acls as $user => $right) {
	    if ($right > 0 && $user != "@admin" ) // admins can see everything
	        array_push($list,$user);
	}
	if (count($list)) {
	    sort($list);
		print "(page visible to: ";
		print join(', ',$list);
		print ")";
	}
	
	// Uncomment this, if you want to display users/groups who cannot access this page, too:
	/* $list = array();	
	foreach ($page_acls as $user => $right) {
	    if ($right == 0)
	        array_push($list,$user);
	}
	if (count($list)) {
	    sort($list);
		print "(page hidden to: ";
		print join(', ',$list);
		print ")";
	}
	*/

}
  ?>

    <div class="meta">
      <div class="user">
        <?php tpl_userinfo()?> 
        <?php tpl_aclinfo()?>
      </div>
      <div class="doc">
        <?php tpl_pageinfo()?>
      </div>
    </div>
</code>