<?php
//
// by Fumi.Iseki 2012/04/12
//

//
// About Capabilities
//	please see http://docs.moodle.org/dev/Roles#Capability-locality_changes_in_v1.9
//

defined('MOODLE_INTERNAL') || die();

$jbxl_moodle_tools_ver = 2013092100;


//
if (defined('JBXL_MOODLE_TOOLS_VER') or defined('_JBXL_MOODLE_TOOLS')) {
	if (defined('JBXL_MOODLE_TOOLS_VER')) {
		if (JBXL_MOODLE_TOOLS_VER < $jbxl_moodle_tools_ver) {
			print_error('JBXL_MOODLE_TOOLS: old version is used. '.JBXL_MOODLE_TOOLS_VER.' < '.$jbxl_moodle_tools_ver);
		}
	}
}
else {

define('JBXL_MOODLE_TOOLS_VER', $jbxl_moodle_tools_ver);


/*******************************************************************************
//
// cntxt: id or context of course
//

// function  jbxl_is_admin($uid)
// function  jbxl_is_teacher($uid, $cntxt)
// function  jbxl_is_assistant($uid, $cntxt)
// function  jbxl_is_student($uid, $cntxt)
// function  jbxl_has_role($uid, $cntxt, $rolename)
//
// function  jbxl_get_course_users($cntxt, $sort='')
// function  jbxl_get_course_students($cntxt, $sort='')
// function  jbxl_get_course_tachers($cntxt, $sort='')
// function  jbxl_get_course_assistants($cntxt, $sort='')
//
// function  jbxl_get_user_first_grouping($courseid, $userid)
//
// function  jbxl_db_exist_table($table, $lower_case=true)
//

*******************************************************************************/


function  jbxl_is_admin($uid)
{
	$admins = get_admins();
	foreach ($admins as $admin) {
		if ($uid==$admin->id) return true;
	}
	return false;
}


function  jbxl_is_teacher($uid, $cntxt, $inc_admin=true)
{
	global $DB;

	if (!$cntxt) return false;
	if (!is_object($cntxt)) $cntxt = get_context_instance(CONTEXT_COURSE, $cntxt);

	$ret = false;
	$roles = $DB->get_records('role', array('archetype'=>'editingteacher'), 'id', 'id'); 
	foreach($roles as $role) {
		$ret = user_has_role_assignment($uid, $role->id, $cntxt->id);
		if ($ret) return $ret;
	}

	if ($inc_admin) {
		$ret = jbxl_is_admin($uid); 
		if (!$ret) $ret = jbxl_has_role($uid, $cntxt, 'manager');
		if (!$ret) $ret = jbxl_has_role($uid, $cntxt, 'coursecreator');
	}
	return $ret;
}


function  jbxl_is_assistant($uid, $cntxt)
{
	global $DB;

	if (!$cntxt) return false;
	if (!is_object($cntxt)) $cntxt = get_context_instance(CONTEXT_COURSE, $cntxt);

	$roles = $DB->get_records('role', array('archetype'=>'teacher'), 'id', 'id'); 
	foreach($roles as $role) {
		$ret = user_has_role_assignment($uid, $role->id, $cntxt->id);
		if ($ret) return $ret;
	}
	return false;
}


function  jbxl_is_student($uid, $cntxt)
{
	global $DB;

	if (!$cntxt) return false;
	if (!is_object($cntxt)) $cntxt = get_context_instance(CONTEXT_COURSE, $cntxt);

	$roles = $DB->get_records('role', array('archetype'=>'student'), 'id', 'id'); 
	foreach($roles as $role) {
		$ret = user_has_role_assignment($uid, $role->id, $cntxt->id);	// slow?
		if ($ret) return $ret;
	}
	return false;
}


function  jbxl_has_role($uid, $cntxt, $rolename)
{
	global $DB;

	if (!$cntxt) return false;
	if (!is_object($cntxt)) $cntxt = get_context_instance(CONTEXT_COURSE, $cntxt);

	$roles = $DB->get_records('role', array('archetype'=>$rolename), 'id', 'id'); 
	foreach($roles as $role) {
		$ret = user_has_role_assignment($uid, $role->id, $cntxt->id);
		if ($ret) return $ret;
	}
	return false;
}


function jbxl_get_course_users($cntxt, $sort='')
{
	global $DB;

	if (!$cntxt) return '';

	if ($sort) $sort = ' ORDER BY u.'.$sort;
	$sql = 'SELECT u.* FROM {role_assignments} r, {user} u WHERE r.contextid = ? AND r.userid = u.id '.$sort;
	//
	if (!is_object($cntxt)) $cntxt = get_context_instance(CONTEXT_COURSE, $cntxt);
	$users = $DB->get_records_sql($sql, array($cntxt->id));

	return $users;
}


function jbxl_get_course_students($cntxt, $sort='')
{
	global $DB;

	if (!$cntxt) return '';

	$roles = $DB->get_records('role', array('archetype'=>'student'), 'id', 'id'); 
	if (empty($roles)) return '';

	$roleid = '';
	foreach($roles as $role) {
		if (!empty($roleid)) $roleid.= ' OR ';
		$roleid.= 'r.roleid = '.$role->id;
	}
	if ($sort) $sort = ' ORDER BY u.'.$sort;

	$sql = 'SELECT u.* FROM {role_assignments} r, {user} u '.
					 ' WHERE r.contextid = ? AND ('.$roleid.') AND r.userid = u.id '.$sort;
	//
	if (!is_object($cntxt)) $cntxt = get_context_instance(CONTEXT_COURSE, $cntxt);
	$users = $DB->get_records_sql($sql, array($cntxt->id));

	return $users;
}


function jbxl_get_course_tachers($cntxt, $sort='')
{
	global $DB;

	if (!$cntxt) return '';

	$roles = $DB->get_records('role', array('archetype'=>'editingteacher'), 'id', 'id'); 
	if (empty($roles)) return '';

	$roleid = '';
	foreach($roles as $role) {
		if (!empty($roleid)) $roleid.= ' OR ';
		$roleid.= 'r.roleid = '.$role->id;
	}
	if ($sort) $sort = ' ORDER BY u.'.$sort;

	$sql = 'SELECT u.* FROM {role_assignments} r, {user} u '. 
					 ' WHERE r.contextid = ? AND ('.$roleid.') AND r.userid = u.id '.$sort;
	//
	if (!is_object($cntxt)) $cntxt = get_context_instance(CONTEXT_COURSE, $cntxt);
	$users = $DB->get_records_sql($sql, array($cntxt->id));

	return $users;
}


function jbxl_get_course_assistants($cntxt, $sort='')
{
	global $DB;

	if (!$cntxt) return '';

	$roles = $DB->get_records('role', array('archetype'=>'teacher'), 'id', 'id'); 
	if (empty($roles)) return '';

	$roleid = '';
	foreach($roles as $role) {
		if (!empty($roleid)) $roleid.= ' OR ';
		$roleid.= 'r.roleid = '.$role->id;
	}
	if ($sort) $sort = ' ORDER BY u.'.$sort;

	$sql = 'SELECT u.* FROM {role_assignments} r, {user} u '.
					 ' WHERE r.contextid = ? AND ('.$roleid.') AND r.userid = u.id '.$sort;
	//
	if (!is_object($cntxt)) $cntxt = get_context_instance(CONTEXT_COURSE, $cntxt);
	$users = $DB->get_records_sql($sql, array($cntxt->id));

	return $users;
}


/*
function jbxl_get_user_first_grouping($courseid, $userid)
{
	/////////////////////////////////
	return 0;	// for DEBUG
	/////////////////////////////////


	if (!$courseid or !$userid) return 0;

	$groupings = groups_get_user_groups($courseid, $userid);
	if (!is_array($groupings)) return 0;

	$keys = array_keys($groupings);
	if (count($keys)>1 && $keys[0]==0) return $keys[1];
	else return $keys[0];
}
*/


//
// Moodle DB (MySQL)
//

function jbxl_db_exist_table($table, $lower_case=true)
{
	global $DB;

	$ret = false;

	$results = $DB->get_records_sql('SHOW TABLES');
	if (is_array($results)) {
		$db_tbls = array_keys($results);
		foreach($db_tbls as $db_tbl) {
			if ($lower_case) $db_tbl = strtolower($db_tbl);
			if ($db_tbl==$table) {
				$ret = true;
				break;
			}
		}
	}

	return $ret;
}			


}		// !defined('JBXL_MOODLE_TOOLS_VER')