<?php  // $Id: lib/locklib.php  beta v 0.1  for Moodle 1.4.5  new Exp $
   // Replacement Library of useful functions for activity locking
  
   
function islocked($module) {
   	global $USER, $CFG, $course;  //It there an alternative to global $course?
   	
   	static $currentcourse, $mods;                                // Hopefully this should reduce the number of queries
   	if (!isset($mods) or !($currentcourse == $course->id)) {     // The idea is, you should only need to download a list of modules in a course once
   		$mods = get_course_mods($course->id);
   		$currentcourse = $course->id;
   	}	
   	
   	if ($module->delay and $module->delay !== "0:0:0") { //module has a time delay
   		$locks['time'] = "closed";
		if ($student = get_record("user_students", "userid", $USER->id, "course", $course->id)) { //user has enrolled
			list($delayday, $delayhour, $delaymin) = explode(":", $module->delay);
			$delay = ($delaymin*60) + ($delayhour*60*60) + ($delayday*24*60*60);
			if (time() > ($student->time + $delay)) { //student waited long enough
				$locks['time'] = "open";
			}		
		}
   	}	
   	
   	if ($modlocks = get_records("course_module_locks", "moduleid", $module->id)) { // Module has locks
   	  foreach($modlocks as $modlock) { //6
   		$lockid = $modlock->lockid;
   		$instance = get_record($mods[$lockid]->modname, "id", $mods[$lockid]->instance);
   		if (record_exists("log", "userid", $USER->id, "module", $mods[$lockid]->modname , "info" , $mods[$lockid]->instance) or $mods[$lockid]->modname == "feedback") { //5
   			$locks[$modlock->lockid]  = "open";
   			$libfile = $CFG->dirroot."/mod/".$mods[$lockid]->modname."/lib.php";
        	if (file_exists($libfile)) { //4
            	require_once($libfile);
            	$gradefunction = $mods[$lockid]->modname."_grades";
            	if (function_exists($gradefunction)) {   // Modules with grade function //3
             	   if ($modgrades = $gradefunction($mods[$lockid]->instance)) { //2
						if (isset($modgrades->grades[$USER->id]) and $modgrades->grades[$USER->id] >= $modlock->requirement) { //1
                    		$locks[$modlock->lockid]  = "open";
                        } else {
                        	$locks[$modlock->lockid] = "closed";
                        }  //1  
                    } //2
              	} //3
            } //4		
   		} else {
		   	$locks[$modlock->lockid] = "closed";
		} //5
      } //6 damn this nesting!		   	
   	} 
	   
	if (isset($locks)) {
		return $locks;
	} else { // No locks on module
   		return false; 
	}
}

function activity_complete($mod) {
	global $USER, $CFG;
	
	$requiredgrade = get_records("course_module_locks", "lockid", $mod->id, "requirement DESC LIMIT 1");
	if (is_array($requiredgrade)) {$requiredgrade = current($requiredgrade);};
		$instance = get_record($mod->modname, "id", $mod->instance);
   		if (record_exists("log", "userid", $USER->id, "module", $mod->modname , "info" , $mod->instance)) {
   			$complete  = true;
   			$libfile = $CFG->dirroot."/mod/".$mod->modname."/lib.php";
    		if (file_exists($libfile)) {
        		require_once($libfile);
        		$gradefunction = $mod->modname."_grades";
        		if (function_exists($gradefunction)) {   // Modules with grade function
        	    	if ($modgrades = $gradefunction($mod->instance)) {
						if (isset($modgrades->grades[$USER->id]) and $modgrades->grades[$USER->id] >= $requiredgrade->requirement) {
         	           		$complete  = true;
                		} else {
                      		$complete = false;
                		}  
            		}
       			}
    		}	
   		} else {
			$complete = false;
		} 	
     		
	return $complete;	
}	

function check_locks($module, $showbutton=1) {
	global $USER, $CFG, $course; 
	if (!isteacher($course->id)) {
		if ($locks = islocked($module)) {
			if (array_search("closed", $locks)) {
				ksort($locks);
				reset($locks);
				return print_lock_notice($locks, $showbutton);	
			}
		}
	}
	return false;
}							

function print_lock_notice($locks, $showbutton) {
	global $USER, $CFG, $course;  //It there an alternative to global $course?

		require_once($CFG->dirroot.'/course/lib.php');
		get_all_mods($course->id, $mods, $modnames, $modnamesplural, $modnamesused);
		$locklist = "";
	
		print_header("$course->shortname", "$course->fullname", 
                     "<A HREF=\"$CFG->wwwroot/course/view.php?id=$course->id\">$course->shortname</A>");
		foreach ($locks as $lock => $status) {
			if (is_numeric($lock) and $status == "closed") {
				$instance = get_record($mods[$lock]->modname, "id", $mods[$lock]->instance);
				$locklist .= "$instance->name<br />";
			} else {
				if ($status == "closed") {
					$locklist .= get_string("timedelay", "lock")."<br />";
				}	
			}		
		}
	switch ($showbutton) {
	case 0:					 	
		print_simple_box("<center>".get_string("activitycurrentlylocked", "lock")."<p><strong>$locklist</strong></p></center>", "CENTER");
		die;
	case 1:
		notice(get_string("activitycurrentlylocked", "lock").'<p><strong>'.$locklist.'</strong></p>');
		break;
	case 2:
		print_simple_box("<center>".get_string("activitycurrentlylocked", "lock")."<p><strong>$locklist</strong></p></center>", "CENTER");
		close_window_button();
		die;	
	}

}

function write_locks_to_db($passmarks, $delay, $moduleid) {
	global $USER, $CFG, $course;
	
		
		$lock->id = $moduleid;
		$lock->delay = $delay;
		update_record("course_modules", $lock);
		unset($lock);

    	delete_records("course_module_locks", "moduleid", $moduleid);
    	while(list($predecessor, $passmark) = each($passmarks)){
    		if (is_numeric($predecessor)) {
    					if ($passmark) {
					$lock->moduleid = $moduleid;
					$lock->courseid = $course->id;
					$lock->lockid = $predecessor;
					$lock->requirement = $passmark;
					insert_record("course_module_locks", $lock);
					unset($lock);				
    			}
			}		
    	}
    	
}    	

?>