lib.php

<?php
/**
 * Library of assorted functions for the ILP
 *
 * @copyright &copy; 2011 University of London Computer Centre
 * @author http://www.ulcc.ac.uk, http://moodle.ulcc.ac.uk
 * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
 * @package ILP
 * @version 2.0
 */



function var_crap($var,$header="") {
	echo "<pre> {$header} <br />";
	var_dump($var);
	echo "</pre>";
	
}

/**
 * Test whether the id is that of an admin user
 *
 * @return bool true or false
 */
function ilp_is_siteadmin($userid) {
    global $CFG;

    if (stripos($CFG->release,"2.") !== false) {
        return is_siteadmin($userid);
    } else {
        $sitecontext = get_context_instance(CONTEXT_SYSTEM);
        return has_capability('moodle/site:doanything',$sitecontext);
    }
}


/**
 * Generates a random number for when something needs to be identified
 * uniquely.
 *
 * @return int A random number
 */
function ilp_uniqueNum() {
    return rand().time();
}



/**
 * Adds a record of an action to the log
 *
 * @param int $course_id
 * @param string $log_action the generic short name for the event
 * @param string $log_url (optional, defaults to ASSMGR_LOG_URL_PREFIX)
 * @param string $log_info Detailed explanation of what has happened
 * @return void
 */
function ilp_add_to_log($course_id, $log_action, $log_url, $log_info) {

    // prepend the url prefix if the log_url is not empty
    $log_url = empty($log_url) ? '' : ILP_LOG_URL_PREFIX.'/'.$log_url;

    // add to the moodle log
    add_to_log($course_id, ILP_LOG_MODULE, $log_action, $log_url, $log_info);
}

/**
 * Utility function which makes a recordset into an array
 * Similar to recordset_to_menu. Array is keyed by the specified field of each record and
 * either has the second specified field as the value, or the results of the callback function which
 * takes the second field as it's first argument
 *
 * field1, field2 is needed because the order from get_records_sql is not reliable
 * @param records - records from get_records_sql() or get_records()
 * @param field1 - field to be used as menu index
 * @param field2 - feild to be used as coresponding menu value
 * @param string $callback (optional) the name of a function to call in order ot generate the menu item for each record
 * @param string $callbackparams (optional) the extra parameters for the callback function
 * @return mixed an associative array, or false if an error occured or the RecordSet was empty.
 */
function ilp_records_to_menu($records, $field1, $field2, $callback = null, $callbackparams = null) {

    $menu = array();

    if(!empty($records)) {
        foreach ($records as $record) {
            if(empty($callback)) {
                $menu[$record->$field1] = $record->$field2;
            } else {
                // array_unshift($callbackparams, $record->$field2);
                $menu[$record->$field1] = call_user_func_array($callback,array($record->$field2,$callbackparams));
            }
        }

    }
    return $menu;
}


function ilp_get_user_role_ids($context,$user_id)	{
	$role_ids	=	array();
	
	if ($roles = get_user_roles($context, $user_id)) {
	 	foreach ($roles as $role) {
	 		$role_ids[]	= $role->roleid;
	 	}
	}
	
	return $role_ids;
}




/**
 * Wrapper for native ilp_build_navigation() function that truncates the length of
 * each of the breadcrumbs to ensure that they all fit neatly on the page
 */
function ilp_build_navigation($breadcrumbs) {

    // determine the total length of all the breadcrumbs
    $length = 0;
    foreach($breadcrumbs as $crumb) {
        $length += strlen($crumb['name']);
    }

    // if it too long then we need to truncate
    if($length > ILP_MAXLENGTH_BREADCRUMB) {
        // calculate the per crumb limit
        $limit = round(ILP_MAXLENGTH_BREADCRUMB/count($breadcrumbs));
        // enforce it
        foreach($breadcrumbs as $id => $crumb) {
            $breadcrumbs[$id]['name'] = ilp_limit_length($crumb['name'], $limit);
        }
    }

    return build_navigation($breadcrumbs);
}



/**
 * Take the given object containing block_ilp_reportpermissions records
 * and converts them to an object with the role_id and capbility as params.
 * This can then be used to populate the reports permission matrix
 * 
 * @param array $permissions recordset of block_ilp_permission records
 * 
 * return mixed object contain param with role_id and capabilty or false
 */
function reportformpermissions($permissions) {
	
	$formpermissions	=	new stdClass();

	//loop through the permissions
	foreach($permissions as $perm) {
		//create the param name 
		$param	=	$perm->role_id."_".$perm->capability_id;
		//set the value of our new param to 1
		$formpermissions->$param	=	1;
	}
	
	return $formpermissions;	
}








/**
 * Truncates long strings and adds a tooltip with a longer verison.
 *
 * @param string $string The string to truncate
 * @param int $maxlength The maximum length the string can be. -1 means unlimited, in case you just want a tooltip
 * @param string $tooltip (optional) tooltip to display. defaults to $string
 * @param array $special_case (optional) array of characters/entities that if found in string
 *              stop the truncation and deceoding
 * @return string HTML
 */
function ilp_limit_length($html, $maxlength, $tooltip = null) {

    // permit only html tags and quotes so we can parse the tags properly
    $html = ilp_db::decode_htmlchars(assmgr_db::encode($html));

    $printedlength = 0;
    $position = 0;
    $tags = array();

    $return = null;

    while ($printedlength < $maxlength && preg_match('{</?([a-z]+)[^>]*>|&#?[a-zA-Z0-9]+;}', $html, $match, PREG_OFFSET_CAPTURE, $position)) {

        list($tag, $tagPosition) = $match[0];

        // print text leading up to the tag
        $str = substr($html, $position, $tagPosition - $position);
        if ($printedlength + strlen($str) > $maxlength) {
            $return .= (substr($str, 0, $maxlength - $printedlength));
            $printedlength = $maxlength;
            break;
        }

        $return .= ($str);
        $printedlength += strlen($str);

        if ($tag[0] == '&') {
            // handle the entity
            $return .= ($tag);
            $printedlength++;
        } else {
            // handle the tag
            $tagName = $match[1][0];
            if ($tag[1] == '/') {
                // this is a closing tag

                $openingTag = array_pop($tags);
                assert($openingTag == $tagName); // check that tags are properly nested

                $return .= ($tag);
            } else if ($tag[strlen($tag) - 2] == '/') {
                // self-closing tag
                $return .= ($tag);
            } else {
                // opening tag
                $return .= ($tag);
                $tags[] = $tagName;
            }
        }

        // continue after the tag
        $position = $tagPosition + strlen($tag);
    }

    // print any remaining text
    if ($printedlength < $maxlength && $position < strlen($html)) {
        $return .= (substr($html, $position, $maxlength - $printedlength));
    }

    // add the ellipsis, if truncated
    $return .= (strip_tags($return) != strip_tags($html)) ? '&hellip;' : null;

    // close any open tags
    while (!empty($tags)) {
        $return .= sprintf('</%s>', array_pop($tags));
    }

    // don't show a tooltip if it's set to false, or if no truncate has been done
    if($tooltip === false || ($return == $html && empty($tooltip))) {
        return $return;
    } else {

        // make the tooltip the original string if a specific value was not set
        if(empty($tooltip)) {
            $tooltip = $html;
        }

        $tooltip = ilp_db::encode($tooltip);

        // generate the unique id needed for the YUI tooltip
        $id = 'tootlip'.ilp_uniqueNum();

        $script = "<script type='text/javascript'>
                       //<![CDATA[
                       new YAHOO.widget.Tooltip('ttA{$id}', {
                           context:'{$id}',
                           effect:{effect:YAHOO.widget.ContainerEffect.FADE,duration:0.20}
                       });
                       //]]>
                   </script>";

        return "<span id='{$id}' class='tooltip' title='{$tooltip}'>{$return}</span>{$script}";
    }
}

function returnNextPosition($takenPos)   {
    $i  =   0;

    do {
        $i++;
    } while (in_array($i,$takenPos));

    return  $i;
}

function ilp_pluginfile($context, $filearea, $args, $forcedownload) {

    if ($context->contextlevel != CONTEXT_SYSTEM) {
        send_file_not_found();
    }

    require_login();

    if ($filearea !== 'ilp_element_plugin_file') {
        send_file_not_found();
    }

    $fs = get_file_storage();

    $filename = array_pop($args);
    $itemid   = array_pop($args);
    $filepath = $args ? '/'.implode('/', $args).'/' : '/';

    if (!$file = $fs->get_file($context->id, 'form_elements', $filearea, $itemid, $filepath, $filename) or $file->is_directory()) {
        send_file_not_found();
    }

    session_get_instance()->write_close();
    send_stored_file($file, 60*60, 0, $forcedownload);
}

?>