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    SimpleORMap.class.php 87.27 KiB
    <?php
    /**
     * SimpleORMap.class.php
     * simple object-relational mapping
     *
     * This program is free software; you can redistribute it and/or
     * modify it under the terms of the GNU General Public License as
     * published by the Free Software Foundation; either version 2 of
     * the License, or (at your option) any later version.
     *
     * @author      André Noack <noack@data-quest.de>
     * @copyright   2010 Stud.IP Core-Group
     * @license     http://www.gnu.org/licenses/gpl-2.0.html GPL version 2
     * @category    Stud.IP
    */
    
    class SimpleORMap implements ArrayAccess, Countable, IteratorAggregate
    {
        /**
         * Defines `_` as character used when joining composite primary keys.
         */
        const ID_SEPARATOR = '_';
    
        /**
         * table row data
         * @var array $content
         */
        protected $content = [];
    
        /**
         * table row data
         * @var array $content_db
         */
        protected $content_db = [];
    
        /**
         * new state of entry
         * @var boolean $is_new
         */
        protected $is_new = true;
    
        /**
         * deleted state of entry
         * @var boolean $is_deleted
         */
        protected $is_deleted = false;
    
         /**
         * db table metadata
         * @var ?array $schemes;
         */
        public static $schemes = null;
    
        /**
         * configuration data for subclasses
         * @see self::configure()
         * @var array $config;
         */
        protected static $config = [];
    
        /**
         * stores instantiated related objects
         * @var array $relations
         */
        protected $relations = [];
    
        /**
         * assoc array for storing values for additional fields
         *
         * @var array $additional_data
         */
        protected $additional_data = [];
    
        /**
         * reserved indentifiers, fields with those names must not have an explicit getXXX() method
         * @var array $reserved_slots
         */
        protected static $reserved_slots = ['value','newid','iterator','tablemetadata', 'relationvalue','wherequery','relationoptions','data','new','id'];
    
        /**
         * indicator for batch operations in findEachBySQL
         *
         * @var bool $performs_batch_operation
         */
        protected static $performs_batch_operation = false;
    
        /**
         * name of db table
         * @return string
         */
        protected static function db_table()
        {
            return static::config('db_table');
        }
    
        /**
         * table columns
         * @return array
         */
        protected static function db_fields()
        {
            return static::config('db_fields');
        }
    
        /**
         * primary key columns
         * @return array
         */
        protected static function pk()
        {
            return static::config('pk');
        }
    
        /**
         * default values for columns
         * @return array
         */
        protected static function default_values()
        {
            return static::config('default_values');
        }
    
        /**
         * list of columns to deserialize
         * @return array key is name of column, value is name of ArrayObject class
         */
        protected static function serialized_fields()
        {
            return static::config('serialized_fields');
        }
    
        /**
         * aliases for columns
         * alias => column
         * @return array
         */
        protected static function alias_fields()
        {
            return static::config('alias_fields');
        }
    
        /**
         * multi-language fields
         * name => boolean
         * @return array
         */
        protected static function i18n_fields()
        {
            return static::config('i18n_fields');
        }
    
        /**
         * additional computed fields
         * name => callable
         * @return array
         */
        protected static function additional_fields()
        {
            return static::config('additional_fields');
        }
    
        /**
         * 1:n relation
         * @return array
         */
        protected static function has_many()
        {
            return static::config('has_many');
        }
    
        /**
         * 1:1 relation
         * @return array
         */
        protected static function has_one()
        {
            return static::config('has_one');
        }
    
        /**
         * n:1 relations
         * @return array
         */
        protected static function belongs_to()
        {
            return static::config('belongs_to');
        }
    
        /**
         * n:m relations
         * @return array
         */
        protected static function has_and_belongs_to_many()
        {
            return static::config('has_and_belongs_to_many');
        }
    
        /**
         * callbacks
         * @return array<string, array<string|Closure>>
         */
        protected static function registered_callbacks()
        {
            return static::config('registered_callbacks');
        }
    
        /**
         * contains an array of all used identifiers for fields
         * (db columns + aliased columns + additional columns + relations)
         * @return array
         */
        protected static function known_slots()
        {
            return static::config('known_slots');
        }
    
        /**
         * assoc array used to map SORM callback to NotificationCenter
         * keys are SORM callbacks, values notifications
         * eg. 'after_create' => 'FooDidCreate'
         *
         * @return array
         */
        protected static function notification_map()
        {
            return static::config('notification_map');
        }
    
        /**
         * assoc array for mapping get/set Methods
         *
         * @return array
         */
        protected static function getter_setter_map()
        {
            return static::config('getter_setter_map');
        }
    
        //////////////////////////////////////////////////
    
        /**
         * set configuration data from subclass
         *
         * @param ?array $config configuration data
         * @return void
         */
        protected static function configure($config = [])
        {
            $class = get_called_class();
    
            if (empty($config['db_table'])) {
                $config['db_table'] = strtolower($class);
            }
    
            if (!isset($config['db_fields'])) {
                if (static::tableScheme($config['db_table'])) {
                    $config['db_fields'] = self::$schemes[$config['db_table']]['db_fields'];
                    $config['pk'] = self::$schemes[$config['db_table']]['pk'];
                }
            }
    
            if (isset($config['pk'])
                && !isset($config['db_fields']['id'])
                && !isset($config['alias_fields']['id'])
                && !isset($config['additional_fields']['id'])
            ) {
                if (count($config['pk']) === 1) {
                    $config['alias_fields']['id'] = $config['pk'][0];
                } else {
                    $config['additional_fields']['id'] = ['get' => '_getId',
                                                               'set' => '_setId'];
                }
            }
            if (isset($config['additional_fields'])) {
                foreach ($config['additional_fields'] as $a_field => $a_config) {
                    if (is_array($a_config) && !(isset($a_config['get']) || isset($a_config['set']))) {
                        $relation = $a_config[0] ?? '';
                        $relation_field = $a_config[1] ?? '';
                        if (!$relation) {
                            list($relation, $relation_field) = explode('_', $a_field);
                        }
                        if (!$relation_field || !$relation) {
                            throw new UnexpectedValueException('no relation found for autoget/set additional field: ' . $a_field);
                        }
                        $config['additional_fields'][$a_field] = ['get'            => '_getAdditionalValueFromRelation',
                                                                       'set'            => '_setAdditionalValue',
                                                                       'relation'       => $relation,
                                                                       'relation_field' => $relation_field];
                    }
                }
            }
            if (isset($config['serialized_fields'])) {
                foreach ($config['serialized_fields'] as $a_field => $object_type) {
                    if (!(is_subclass_of($object_type, 'StudipArrayObject'))) {
                        throw new UnexpectedValueException(sprintf('serialized field %s must use subclass of StudipArrayObject', $a_field));
                    }
                }
            }
    
            foreach (['default_values', 'serialized_fields', 'alias_fields', 'i18n_fields', 'additional_fields'] as $fields) {
                if (!isset($config[$fields])) {
                    $config[$fields] = [];
                }
            }
    
            foreach (['has_many', 'belongs_to', 'has_one', 'has_and_belongs_to_many'] as $type) {
                if (isset($config[$type]) && is_array($config[$type])) {
                    foreach (array_keys($config[$type]) as $one) {
                        $config['relations'][$one] = null;
                    }
                } else {
                    $config[$type] = [];
                }
            }
    
            $callbacks = ['before_create',
                          'before_update',
                          'before_store',
                          'before_delete',
                          'before_initialize',
                          'after_create',
                          'after_update',
                          'after_store',
                          'after_delete',
                          'after_initialize'];
    
            foreach ($callbacks as $callback) {
                if (!isset($config['registered_callbacks'][$callback])) {
                    $config['registered_callbacks'][$callback] = [];
                }
            }
    
            $auto_notification_map['after_create'] = $class . 'DidCreate';
            $auto_notification_map['after_store'] = $class . 'DidStore';
            $auto_notification_map['after_delete'] = $class . 'DidDelete';
            $auto_notification_map['after_update'] = $class . 'DidUpdate';
            $auto_notification_map['before_create'] = $class . 'WillCreate';
            $auto_notification_map['before_store'] = $class . 'WillStore';
            $auto_notification_map['before_delete'] = $class . 'WillDelete';
            $auto_notification_map['before_update'] = $class . 'WillUpdate';
    
            foreach ($auto_notification_map as $cb => $notification) {
                if (isset($config['notification_map'][$cb])) {
                    if (strpos($config['notification_map'][$cb], $notification) !== false) {
                        $config['notification_map'][$cb] .= ' ' . $notification;
                    }
                } else {
                    $config['notification_map'][$cb] = $notification;
                }
            }
    
            if (is_array($config['notification_map'])) {
                foreach (array_keys($config['notification_map']) as $cb) {
                    $config['registered_callbacks'][$cb][] = 'cbNotificationMapper';
                }
            }
    
            if (!I18N::isEnabled() || empty($config['i18n_fields'])) {
                $config['i18n_fields'] = [];
            } elseif (is_string($config['i18n_fields'])) {
                $i18n_fields = words($config['i18n_fields']);
                $config['i18n_fields'] = array_combine(
                    $i18n_fields,
                    array_fill(0, count($i18n_fields), true)
                );
            } elseif (array_is_list($config['i18n_fields'])) {
                $config['i18n_fields'] = array_combine(
                    $config['i18n_fields'],
                    array_fill(0, count($config['i18n_fields']), true)
                );
            }
    
            array_unshift($config['registered_callbacks']['after_initialize'], 'cbAfterInitialize');
    
            $config['known_slots'] = array_merge(
                array_keys($config['db_fields']),
                array_keys($config['alias_fields'] ?? []),
                array_keys($config['additional_fields'] ?? []),
                array_keys($config['relations'] ?? [])
            );
    
            foreach (array_map('strtolower', get_class_methods($class)) as $method) {
                if (in_array(substr($method, 0, 3), ['get', 'set'])) {
                    $verb = substr($method, 0, 3);
                    $name = substr($method, 3);
                    if (in_array($name, $config['known_slots']) && !in_array($name, static::$reserved_slots) && !isset($config['additional_fields'][$name][$verb])) {
                        $config['getter_setter_map'][$name][$verb] = $method;
                    }
                }
            }
            self::$config[$class] = $config;
        }
    
        /**
         * fetch config data for the called class
         *
         * @param string $key config key
         * @return mixed value of config key (null if not set)
         */
        protected static function config($key)
        {
            if (!array_key_exists(static::class, self::$config)) {
                static::configure();
            }
    
            return self::$config[static::class][$key] ?? null;
        }
    
        /**
         * fetch table metadata from db or from local cache
         *
         * @param string $db_table
         * @return bool true if metadata could be fetched
         */
        public static function tableScheme($db_table)
        {
            if (self::$schemes === null) {
                $cache = StudipCacheFactory::getCache();
                self::$schemes = unserialize($cache->read('DB_TABLE_SCHEMES'));
            }
            if (!isset(self::$schemes[$db_table])) {
                $db = DBManager::get()->query("SHOW COLUMNS FROM $db_table");
                while($rs = $db->fetch(PDO::FETCH_ASSOC)){
                    $db_fields[strtolower($rs['Field'])] = [
                        'name' => $rs['Field'],
                        'null' => $rs['Null'],
                        'default' => $rs['Default'],
                        'type' => $rs['Type'],
                        'extra' => $rs['Extra']
                    ];
                    if ($rs['Key'] == 'PRI'){
                        $pk[] = strtolower($rs['Field']);
                    }
                }
                self::$schemes[$db_table]['db_fields'] = $db_fields;
                self::$schemes[$db_table]['pk'] = $pk;
                $cache = StudipCacheFactory::getCache();
                $cache->write('DB_TABLE_SCHEMES', serialize(self::$schemes));
            }
            return isset(self::$schemes[$db_table]);
        }
    
        /**
         * force reload of cached table metadata
         * @return void
         */
        public static function expireTableScheme()
        {
            StudipCacheFactory::getCache()->expire('DB_TABLE_SCHEMES');
            self::$schemes = null;
            self::$config = [];
        }
    
        /**
         * Returns new instance for given key when found in the database, else null.
         *
         * @param string $id primary key
         * @return static|null
         */
        public static function find($id)
        {
            $class = get_called_class();
            $ref = new ReflectionClass($class);
            /** @var static $record */
            $record = $ref->newInstanceArgs(func_get_args());
            if (!$record->isNew()) {
                return $record;
            } else {
                return null;
            }
        }
    
        /**
         * Returns true if given key exists in the database.
         *
         * @param string|array $id primary key
         * @return boolean
         */
        public static function exists($id)
        {
            $ret = false;
            $db_table = static::db_table();
            $class = get_called_class();
            $record = new $class();
            call_user_func_array([$record, 'setId'], func_get_args());
            $where_query = $record->getWhereQuery();
            if ($where_query) {
                $query = "SELECT 1 FROM `$db_table` WHERE "
                        . join(" AND ", $where_query);
                $ret = (bool)DBManager::get()->query($query)->fetchColumn();
            }
            return $ret;
        }
    
        /**
         * returns number of records
         *
         * @param ?string $sql sql clause to use on the right side of WHERE
         * @param ?array $params params for query
         * @return int
         */
        public static function countBySql($sql = '1', $params = [])
        {
            $db_table = static::db_table();
            $db = DBManager::get();
            $has_join = stripos($sql, 'JOIN ');
            if ($has_join === false || $has_join > 10) {
                $sql = 'WHERE ' . $sql;
            }
            $sql = "SELECT count(*) FROM `" .  $db_table . "` " . $sql;
            $st = $db->prepare($sql);
            $st->execute($params);
            return (int)$st->fetchColumn();
        }
    
        /**
         * creates new record with given data in db
         * returns the new object or null
         * @param array $data assoc array of record
         * @return ?static
         */
        public static function create($data)
        {
            $class = get_called_class();
            $record = new $class();
            $record->setData($data, false);
            if ($record->store()) {
                return $record;
            } else {
                return null;
            }
        }
    
        /**
         * build object with given data
         *
         * @param array $data assoc array of record
         * @param ?bool $is_new set object to new state
         * @return static
         */
        public static function build($data, $is_new = true)
        {
            $class = get_called_class();
            /** @var static $record */
            $record = new $class();
            $record->setData($data, !$is_new);
            $record->setNew($is_new);
            return $record;
        }
    
        /**
         * build object with given data and mark it as existing
         *
         * @param array $data assoc array of record
         * @return static
         */
        public static function buildExisting($data)
        {
            return static::build($data, false);
        }
    
        /**
         * generate SimpleORMap object structure from assoc array
         * if given array contains data of related objects in sub-arrays
         * they are also generated. Existing records are updated, new records are created
         * (but changes are not yet stored)
         *
         * @param array $data
         * @return static
         */
        public static function import($data)
        {
            $class = get_called_class();
            $record_data = [];
            $relation_data = [];
            foreach ($data as $key => $value) {
                if (is_array($value)) {
                    $relation_data[$key] = $value;
                } else {
                    $record_data[$key] = $value;
                }
            }
            $record = static::toObject($record_data);
            if (!$record instanceof $class) {
                $record = new $class();
                $record->setData($record_data, true);
            } else {
                $record->setData($record_data);
            }
            if (is_array($relation_data)) {
                foreach ($relation_data as $relation => $data) {
                    $options = $record->getRelationOptions($relation);
                    if ($options['type'] == 'has_one') {
                        $record->{$relation} = call_user_func([$options['class_name'], 'import'], $data);
                    }
                    if ($options['type'] == 'has_many' || $options['type'] == 'has_and_belongs_to_many') {
                        foreach ($data as $one) {
                            $current = call_user_func([$options['class_name'], 'import'], $one);
                            if ($options['type'] == 'has_many') {
                                $foreign_key_value = call_user_func($options['assoc_func_params_func'], $record);
                                call_user_func($options['assoc_foreign_key_setter'], $current, $foreign_key_value);
                            }
                            if ($current->id !== null) {
                                $existing = $record->{$relation}->find($current->id);
                                if ($existing) {
                                    $existing->setData($current);
                                } else {
                                    $record->{$relation}->append($current);
                                }
                            } else {
                                $record->{$relation}->append($current);
                            }
                        }
                    }
                }
            }
            return $record;
        }
    
        /**
         * returns array of instances of given class filtered by given sql
         * @param string $sql sql clause to use on the right side of WHERE
         * @param ?array $params parameters for query
         * @return static[] array of "self" objects
         */
        public static function findBySQL($sql, $params = [])
        {
            $db_table = static::db_table();
    
            $has_join = stripos($sql, 'JOIN ');
            if ($has_join === false || $has_join > 10) {
                $sql = 'WHERE ' . $sql;
            }
            $sql = "SELECT `" . $db_table . "`.* FROM `" . $db_table . "` " . $sql;
            $stmt = DBManager::get()->prepare($sql);
            $stmt->execute($params);
    
            $record = static::build([], false);
    
            $ret = [];
            do  {
                $clone = clone $record;
                $clone->setNew(false);
                $stmt->setFetchMode(PDO::FETCH_INTO, $clone);
    
                if ($clone = $stmt->fetch()) {
                    $clone->applyCallbacks('after_initialize');
                    $ret[] = $clone;
                }
            } while ($clone);
            return $ret;
        }
    
        /**
         * returns one instance of given class filtered by given sql
         * only first row of query is used
         * @param string $where sql clause to use on the right side of WHERE
         * @param ?array $params parameters for query
         * @return ?static
         */
        public static function findOneBySQL($where, $params = [])
        {
            if (stripos($where, 'LIMIT') === false) {
                $where .= " LIMIT 1";
            }
            $found = static::findBySQL($where, $params);
            return isset($found[0]) ? $found[0] : null;
        }
    
        /**
         * find related records for a n:m relation (has_many_and_belongs_to_many)
         * using a combination table holding the keys
         *
         * @param string $foreign_key_value value of foreign key to find related records
         * @param array $options relation options from other side of relation
         * @return static[] array of "self" objects
         */
        public static function findThru($foreign_key_value, $options)
        {
            $thru_table = $options['thru_table'];
            $thru_key = $options['thru_key'];
            $thru_assoc_key = $options['thru_assoc_key'];
            $assoc_foreign_key = $options['assoc_foreign_key'];
    
            $db_table = static::db_table();
    
            $sql = "SELECT `$db_table`.* FROM `$thru_table`
            INNER JOIN `$db_table` ON `$thru_table`.`$thru_assoc_key` = `$db_table`.`$assoc_foreign_key`
            WHERE `$thru_table`.`$thru_key` = ? " . ($options['order_by'] ?? '');
            $st = DBManager::get()->prepare($sql);
            $st->execute([$foreign_key_value]);
    
            $record = static::build([], false);
    
            $ret = [];
            do {
                $clone = clone $record;
                $clone->setNew(false);
                $st->setFetchMode(PDO::FETCH_INTO, $clone);
    
                if ($clone = $st->fetch()) {
                    $clone->applyCallbacks('after_initialize');
                    $ret[] = $clone;
                }
            } while ($clone);
            return $ret;
        }
    
        /**
         * passes objects for given sql through given callback
         *
         * @param callable $callable callback which gets the current record as param
         * @param string $sql where clause of sql
         * @param ?array $params sql statement parameters
         * @return integer number of found records
         */
        public static function findEachBySQL($callable, $sql, $params = [])
        {
            $has_join = stripos($sql, 'JOIN ');
            if ($has_join === false || $has_join > 10) {
                $sql = "WHERE {$sql}";
            }
    
            $db_table = static::db_table();
            $st = DBManager::get()->prepare("SELECT `{$db_table}`.* FROM `{$db_table}` {$sql}");
            $st->execute($params);
    
            // Indicate that we are performing a batch operation
            static::$performs_batch_operation = true;
    
            $record = static::build([], false);
    
            $ret = 0;
            do {
                $clone = clone $record;
                $clone->setNew(false);
                $st->setFetchMode(PDO::FETCH_INTO, $clone);
    
                if ($clone = $st->fetch()) {
                    $clone->applyCallbacks('after_initialize');
                    $callable($clone, $ret++);
                }
            } while ($clone);
    
            // Reset batch operation indicator
            static::$performs_batch_operation = false;
    
            return $ret;
        }
    
        /**
         * returns array of instances of given class for by given pks
         * @param ?array $pks array of primary keys
         * @param ?string $order order by clause
         * @param ?array $order_params
         * @return static[]
         */
        public static function findMany($pks = [], $order = '', $order_params = [])
        {
            $db_table = static::db_table();
            $pk = static::pk();
            $db = DBManager::get();
            if (count($pk) > 1) {
                throw new Exception('not implemented yet');
            }
            $where = "`$db_table`.`{$pk[0]}` IN ("  . $db->quote($pks) . ") ";
            return static::findBySQL($where . $order, $order_params);
        }
    
        /**
         * passes objects for by given pks through given callback
         *
         * @param callable $callable callback which gets the current record as param
         * @param ?array $pks array of primary keys of called class
         * @param ?string $order order by sql
         * @param ?array $order_params
         * @return integer number of found records
         */
        public static function findEachMany($callable, $pks = [], $order = '', $order_params = [])
        {
            $db_table = static::db_table();
            $pk = static::pk();
            $db = DBManager::get();
            if (count($pk) > 1) {
                throw new Exception('not implemented yet');
            }
            $where = "`$db_table`.`{$pk[0]}` IN ("  . $db->quote($pks) . ") ";
            return static::findEachBySQL($callable, $where . $order, $order_params);
        }
    
        /**
         * passes objects for given sql through given callback
         * and returns an array of callback return values
         *
         * @param callable $callable callback which gets the current record as param
         * @param string $where where clause of sql
         * @param array $params sql statement parameters
         * @return array return values of callback
         */
        public static function findAndMapBySQL($callable, $where, $params = [])
        {
            $ret = [];
            $calleach = function($m) use (&$ret, $callable) {
                $ret[] = $callable($m);
            };
            static::findEachBySQL($calleach, $where, $params);
            return $ret;
        }
    
        /**
         * passes objects for by given pks through given callback
         * and returns an array of callback return values
         *
         * @param callable $callable callback which gets the current record as param
         * @param ?array $pks array of primary keys of called class
         * @param ?string $order order by sql
         * @param ?array $order_params
         * @return array return values of callback
         */
        public static function findAndMapMany($callable, $pks = [], $order = '', $order_params = [])
        {
            $ret = [];
            $calleach = function($m) use (&$ret, $callable) {
                $ret[] = $callable($m);
            };
            $db_table = static::db_table();
            $pk = static::pk();
            $db = DBManager::get();
            if (count($pk) > 1) {
                throw new Exception('not implemented yet');
            }
            $where = "`$db_table`.`{$pk[0]}` IN ("  . $db->quote($pks) . ") ";
            static::findEachBySQL($calleach, $where . $order, $order_params);
            return $ret;
        }
    
        /**
         * deletes objects specified by sql clause
         * @param string $where sql clause to use on the right side of WHERE
         * @param ?array $params parameters for query
         * @return integer number of deleted records
         */
        public static function deleteBySQL($where, $params = [])
        {
            $killeach = function($record) {$record->delete();};
            return static::findEachBySQL($killeach, $where, $params);
        }
    
        /**
         * returns object of given class for given id or null
         * the param could be a string, an assoc array containing primary key field
         * or an already matching object. In all these cases an object is returned
         *
         * @param string|static|array $id_or_object id as string, object or assoc array
         * @return static
         */
        public static function toObject($id_or_object)
        {
            $class = get_called_class();
            if ($id_or_object instanceof $class) {
                return $id_or_object;
            }
            if (is_array($id_or_object)) {
                $pk = static::pk();
                $key_values = [];
                foreach ($pk as $key) {
                    if (array_key_exists($key, $id_or_object)) {
                        $key_values[] = $id_or_object[$key];
                    }
                }
                if (count($pk) === count($key_values)) {
                    if (count($pk) === 1) {
                        $id = $key_values[0];
                    } else {
                        $id = $key_values;
                    }
                } else {
                    $id = null;
                }
            } else {
                $id = $id_or_object;
            }
            return call_user_func([$class, 'find'], $id);
        }
    
        /**
         * interceptor for static findByColumn / findEachByColumn / countByColumn /
         * deleteByColumn magic
         * @param string $name
         * @param array $arguments
         * @throws BadMethodCallException
         * @return int|static|static[]
         */
        public static function __callStatic($name, $arguments)
        {
            $db_table = static::db_table();
            $alias_fields = static::alias_fields();
            $db_fields = static::db_fields();
            $name = strtolower($name);
            $class = get_called_class();
            $order = '';
            $param_arr = [];
            $where = '';
            $where_param = is_array($arguments[0]) ? $arguments[0] : [$arguments[0]];
            $prefix = strstr($name, 'by', true);
            $field = substr($name, strlen($prefix) + 2);
            switch ($prefix) {
                case 'findone':
                    $order = $arguments[1] ?? '';
                    $param_arr[0] =& $where;
                    $param_arr[1] = [$where_param];
                    $method = 'findonebysql';
                    break;
                case 'find':
                case 'findmany':
                    $order = $arguments[1] ?? '';
                    $param_arr[0] =& $where;
                    $param_arr[1] = [$where_param];
                    $method = 'findbysql';
                    break;
                case 'findeach':
                case 'findeachmany':
                    $order = $arguments[2] ?? '';
                    $param_arr[0] = $arguments[0];
                    $param_arr[1] =& $where;
                    $param_arr[2] = [$arguments[1]];
                    $method = 'findeachbysql';
                    break;
                case 'count':
                case 'delete':
                    $param_arr[0] =& $where;
                    $param_arr[1] = [$where_param];
                    $method = "{$prefix}bysql";
                    break;
                default:
                    throw new BadMethodCallException("Method $class::$name not found");
            }
            if (isset($alias_fields[$field])) {
                $field = $alias_fields[$field];
            }
            if (isset($db_fields[$field])) {
                $where = "`$db_table`.`$field` IN(?) " . $order;
                return call_user_func_array([$class, $method], $param_arr);
            }
            throw new BadMethodCallException("Method $class::$name not found");
        }
    
        /**
         * constructor, give primary key of record as param to fetch
         * corresponding record from db if available, if not preset primary key
         * with given value. Give null to create new record
         *
         * @param null|int|string|array $id primary key of table
         */
        function __construct($id = null)
        {
            foreach(['has_many', 'belongs_to', 'has_one', 'has_and_belongs_to_many'] as $type) {
                foreach (array_keys($this->$type()) as $one) {
                    $this->relations[$one] = null;
                }
            }
    
            if ($id) {
                $this->setId($id);
            }
            $this->restore();
        }
    
        /**
         * returns internal used id value (multiple keys concatenated with _)
         * @param mixed $field unused parameter
         * @return ?string
         */
        protected function _getId($field)
        {
            return is_null($this->getId())
                 ? null
                 : implode(self::ID_SEPARATOR, $this->getId());
        }
    
        /**
         * sets internal used id value (multiple keys concatenated with _)
         * @param string $field Field to set (unused since it's always the id)
         * @param string $value Value for id field
         * @return bool
         */
        protected function _setId($field, $value)
        {
            return $this->setId(explode(self::ID_SEPARATOR, $value));
        }
    
        /**
         * retrieves an additional field value from relation
         *
         * @param string $field
         * @return mixed
         */
        protected function _getAdditionalValueFromRelation($field)
        {
            list($relation, $relation_field) = [$this->additional_fields()[$field]['relation'],
                                                    $this->additional_fields()[$field]['relation_field']];
            if (!array_key_exists($field, $this->additional_data)) {
                $this->_setAdditionalValue($field, $this->getRelationValue($relation, $relation_field));
            }
            return $this->additional_data[$field];
        }
    
        /**
         * sets additional value in field imported from relation
         *
         * @param string $field
         * @param mixed $value
         * @return mixed
         */
        protected function _setAdditionalValueFromRelation($field, $value)
        {
            list($relation, $relation_field) = [$this->additional_fields()[$field]['relation'],
                    $this->additional_fields()[$field]['relation_field']];
            $this->$relation->$field = $value;
            unset($this->additional_data[$field]);
            return $this->_getAdditionalValueFromRelation($field);
        }
    
        /**
         * @param string $field
         * @return mixed
         */
        protected function _getAdditionalValue($field)
        {
            return $this->additional_data[$field];
        }
    
        /**
         * @param string $field
         * @param mixed $value
         * @return mixed
         */
        protected function _setAdditionalValue($field, $value)
        {
            return $this->additional_data[$field] = $value;
        }
    
        /**
         * clean up references after cloning
         * @return void
         */
        function __clone()
        {
            $this->setNew(true);
            //all references link still to old object => reset all aliases
            foreach ($this->alias_fields() as $alias => $field) {
                if (isset($this->db_fields()[$field])) {
                    $content_value = $this->content[$field];
                    $content_db_value = $this->content_db[$field];
                    unset($this->content[$alias]);
                    unset($this->content_db[$alias]);
                    unset($this->content[$field]);
                    unset($this->content_db[$field]);
                    if (is_object($content_value)) {
                        $this->content[$field] = clone $content_value;
                    } else {
                        $this->content[$field] = $content_value;
                    }
                    if (is_object($content_db_value)) {
                        $this->content_db[$field] = clone $content_db_value;
                    } else {
                        $this->content_db[$field] = $content_db_value;
                    }
                    $this->content[$alias] =& $this->content[$field];
                    $this->content_db[$alias] =& $this->content_db[$field];
                }
            }
            //unset all relations for now
            //TODO: maybe a deep copy of all belonging objects is more appropriate
            foreach(['has_many', 'belongs_to', 'has_one', 'has_and_belongs_to_many'] as $type) {
                foreach (array_keys($this->$type()) as $one) {
                    $this->relations[$one] = null;
                }
            }
            //begun the clone war has... hmpf
        }
    
        /**
         * try to determine all needed options for a relationship from
         * configured options
         *
         * @param string $type
         * @param string $name
         * @param array $options
         * @throws Exception if options for thru_table could not be determined
         * @return array
         */
        protected function parseRelationOptions($type, $name, $options)
        {
            if (empty($options['class_name'])) {
                throw new Exception('Option class_name not set for relation ' . $name);
            }
            if (empty($options['assoc_foreign_key'])) {
                if ($type === 'has_many' || $type === 'has_one') {
                    $options['assoc_foreign_key'] = $this->pk()[0];
                } else if ($type === 'belongs_to') {
                    $options['assoc_foreign_key'] = 'id';
                }
            }
            if ($type === 'has_and_belongs_to_many') {
                $thru_table = $options['thru_table'];
                if (empty($options['thru_key'])) {
                    $options['thru_key'] = $this->pk()[0];
                }
                if (empty($options['thru_assoc_key']) || empty($options['assoc_foreign_key'])) {
                    $class = $options['class_name'];
                    $record = new $class();
                    $meta = $record->getTableMetadata();
                    if (empty($options['thru_assoc_key'])) {
                        $options['thru_assoc_key'] = $meta['pk'][0];
                    }
                    if (empty($options['assoc_foreign_key'])) {
                        $options['assoc_foreign_key']= $meta['pk'][0];
                    }
                }
                static::tableScheme($thru_table);
                if (is_array(self::$schemes[$thru_table])) {
                    $thru_key_ok = isset(self::$schemes[$thru_table]['db_fields'][$options['thru_key']]);
                    $thru_assoc_key_ok = isset(self::$schemes[$thru_table]['db_fields'][$options['thru_assoc_key']]);
                }
                if (!$thru_assoc_key_ok || !$thru_key_ok) {
                    throw new Exception("Could not determine keys for relation " . $name . " through table " . $thru_table);
                }
                if ($options['assoc_foreign_key'] instanceof Closure) {
                    throw new Exception("For relation " . $name . " assoc_foreign_key must be a name of a column");
                }
            }
            if (empty($options['assoc_func'])) {
                if ($type !== 'has_and_belongs_to_many') {
                    $options['assoc_func'] = $options['assoc_foreign_key'] === 'id' ? 'find' : 'findBy' . $options['assoc_foreign_key'];
                } else {
                    $options['assoc_func'] = 'findThru';
                }
            }
            if (empty($options['foreign_key'])) {
                $options['foreign_key'] = 'id';
            }
            if (isset($options['foreign_key']) && $options['foreign_key'] instanceof Closure) {
                $options['assoc_func_params_func'] = function($record) use ($name, $options) { return call_user_func($options['foreign_key'], $record, $name, $options);};
            } else {
                $options['assoc_func_params_func'] = function($record) use ($name, $options) { return $options['foreign_key'] === 'id' ? $record->getId() : $record->getValue($options['foreign_key']);};
            }
            if (isset($options['assoc_foreign_key']) && $options['assoc_foreign_key'] instanceof Closure) {
                if ($type === 'belongs_to') {
                    $options['assoc_foreign_key_getter'] = function($record, $that) use ($name, $options) { return call_user_func($options['assoc_foreign_key'], $record, $name, $options, $that);};
                } else {
                    $options['assoc_foreign_key_setter'] = function($record, $params) use ($name, $options) { return call_user_func($options['assoc_foreign_key'], $record, $params, $name, $options);};
                }
            } elseif (!empty($options['assoc_foreign_key'])) {
                if ($type === 'belongs_to') {
                    $options['assoc_foreign_key_getter'] = function($record, $that) use ($name, $options) { return $record->getValue($options['assoc_foreign_key']);};
                } else {
                    $options['assoc_foreign_key_setter'] = function($record, $value) use ($name, $options) { return $record->setValue($options['assoc_foreign_key'], $value);};
                }
            } else {
                throw new Exception("Could not determine assoc_foreign_key for relation " . $name);
            }
            return $options;
        }
    
        /**
         * returns array with option for given relation
         * available options:
         * 'type':                   relation type, on of 'has_many', 'belongs_to', 'has_one', 'has_and_belongs_to_many'
         * 'class_name':             name of class for related records
         * 'foreign_key':            name of column with foreign key
         *                           or callback to retrieve foreign key value
         * 'assoc_foreign_key':      name of foreign key column in related class
         * 'assoc_func':             name of static method to call on related class to find related records
         * 'assoc_func_params_func': callback to retrieve params for assoc_func
         * 'thru_table':             name of relation table for n:m relation
         * 'thru_key':               name of column holding foreign key in relation table
         * 'thru_assoc_key':         name of column holding foreign key from related class in relation table
         * 'on_delete':              contains simply 'delete' to indicate that related records should be deleted
         *                           or callback to invoke before record gets deleted
         * 'on_store':               contains simply 'store' to indicate that related records should be stored
         *                           or callback to invoke after record gets stored
         *
         * @param string $relation name of relation
         * @return array assoc array containing options
         */
        function getRelationOptions($relation)
        {
            $options = [];
            foreach(['has_many', 'belongs_to', 'has_one', 'has_and_belongs_to_many'] as $type) {
                if (isset($this->$type()[$relation])) {
                    $options = self::$config[get_class($this)][$type][$relation];
                    if (!isset($options['type'])) {
                        $options = $this->parseRelationOptions($type, $relation, $options, $this->db_table());
                        $options['type'] = $type;
                        self::$config[get_class($this)][$type][$relation] = $options;
                    }
                    break;
                }
            }
            return $options;
        }
    
        /**
         * returns table and columns metadata
         *
         * @return array assoc array with columns, primary keys and name of table
         */
        function getTableMetadata()
        {
            return ['fields' => $this->db_fields(),
                         'pk' => $this->pk(),
                         'table' => $this->db_table(),
                         'additional_fields' => $this->additional_fields(),
                         'alias_fields' => $this->alias_fields(),
                         'relations' => array_keys($this->relations)];
        }
    
        /**
         * returns true, if table has an auto_increment column
         *
         * @return boolean
         */
        function hasAutoIncrementColumn()
        {
            return $this->db_fields()[$this->pk()[0]]['extra'] == 'auto_increment';
        }
    
        /**
         * set primary key for entry, combined keys must be passed as array
         * @param int|string|array $id primary key
         * @throws InvalidArgumentException if given key is not complete
         * @return boolean
         */
        public function setId($id)
        {
            if (!is_array($id)){
                $id = [$id];
            }
            if (count($this->pk()) != count($id)){
                throw new InvalidArgumentException("Invalid ID, Primary Key {$this->db_table()} is " .join(",",$this->pk()));
            } else {
                foreach ($this->pk() as $count => $key){
                    $this->content[$key] = $id[$count];
                }
                return true;
            }
        }
    
        /**
         * returns primary key, multiple keys as array
         * @return null|string|array current primary key, null if not set
         */
        function getId()
        {
            if (count($this->pk()) == 1) {
                return $this->content[$this->pk()[0]] ?? null;
            } else {
                $id = [];
                foreach ($this->pk() as $key) {
                    if (array_key_exists($key, $this->content)) {
                        $id[] = $this->content[$key];
                    }
                }
                return (count($this->pk()) == count($id) ? $id : null);
            }
        }
    
        /**
         * create new unique pk as md5 hash
         * if pk consists of multiple columns, false is returned
         * @return boolean|string
         */
        function getNewId()
        {
            $id = false;
            if (count($this->pk()) == 1) {
                do {
                    $id = md5(uniqid($this->db_table(), 1));
                    $db = DBManager::get()->query("SELECT `{$this->pk()[0]}` FROM `{$this->db_table()}` "
                    . "WHERE `{$this->pk()[0]}` = '$id'");
                } while($db->fetch());
            }
            return $id;
        }
    
        /**
         * returns data of table row as assoc array
         * pass array of fieldnames or ws separated string to limit
         * fields
         *
         * @param null|array|string $only_these_fields limit returned fields
         * @return array
         */
        function toArray($only_these_fields = null)
        {
            $ret = [];
            if (is_string($only_these_fields)) {
                $only_these_fields = words($only_these_fields);
            }
            $fields = array_diff($this->known_slots(), array_keys($this->relations));
            if (is_array($only_these_fields)) {
                $only_these_fields = array_filter(array_map(function($s) {
                    return is_string($s) ? strtolower($s) : null;
                }, $only_these_fields));
                $fields = array_intersect($only_these_fields, $fields);
            }
            foreach ($fields as $field) {
                $ret[$field] = $this->getValue($field);
                if ($ret[$field] instanceof StudipArrayObject) {
                    $ret[$field] = $ret[$field]->getArrayCopy();
                }
            }
            return $ret;
        }
    
        /**
         * Returns data of table row as assoc array with raw contents like
         * they are in the database.
         * Pass array of fieldnames or ws separated string to limit
         * fields.
         *
         * @param null|array|string $only_these_fields
         * @return array
         */
        function toRawArray($only_these_fields = null)
        {
            $ret = [];
            if (is_string($only_these_fields)) {
                $only_these_fields = words($only_these_fields);
            }
            $fields = array_keys($this->db_fields());
            if (is_array($only_these_fields)) {
                $only_these_fields = array_filter(array_map(function ($s) {
                    return is_string($s) ? strtolower($s) : null;
                }, $only_these_fields));
                $fields = array_intersect($only_these_fields, $fields);
            }
            foreach ($fields as $field) {
                if ($this->content[$field] instanceof I18NString) {
                    $ret[$field] = $this->content[$field]->original();
                } elseif ($this->content[$field] === null) {
                    $ret[$field] = null;
                } else {
                    $ret[$field] = (string)$this->content[$field];
                }
            }
            return $ret;
        }
    
        /**
         * returns data of table row as assoc array
         * including related records with a 'has*' relationship
         * recurses one level without param
         *
         * $only_these_fields limits output for relationships in this way:
         * $only_these_fields = array('field_1',
         *                            'field_2',
         *                            'relation1',
         *                            'relation2' => array('rel2_f1',
         *                                                 'rel2_f2',
         *                                                 'rel2_rel11' => array(
         *                                                           rel2_rel1_f1)
         *                                                )
         *                           )
         * Here all fields of relation1 will be returned.
         *
         * @param null|array|string $only_these_fields limit returned fields
         * @return array
         */
        function toArrayRecursive($only_these_fields = null)
        {
            if (is_string($only_these_fields)) {
                $only_these_fields = words($only_these_fields);
            }
            if (is_null($only_these_fields)) {
                $only_these_fields = $this->known_slots();
            }
            $ret = $this->toArray($only_these_fields);
            $relations = [];
            if (is_array($only_these_fields)) {
                foreach ($only_these_fields as $key => $value) {
                    if (!is_array($value) &&
                        array_key_exists(strtolower($value), $this->relations)
                    ) {
                        $relations[strtolower($value)] = 0; //not null|array|string to stop recursion
                    }
                    if (array_key_exists(strtolower($key), $this->relations)) {
                        $relations[strtolower($key)] = $value;
                    }
                }
            }
            if (count($relations)) {
                foreach ($relations as $relation_name => $relation_only_these_fields) {
                    $options = $this->getRelationOptions($relation_name);
                    if ($options['type'] === 'has_one' ||
                            $options['type'] === 'belongs_to') {
                        $ret[$relation_name] =
                                $this->{$relation_name}->
                                                toArrayRecursive($relation_only_these_fields);
                    }
                    if ($options['type'] === 'has_many' ||
                        $options['type'] === 'has_and_belongs_to_many') {
                        $ret[$relation_name] =
                                $this->{$relation_name}->
                                                sendMessage('toArrayRecursive',
                                                [$relation_only_these_fields]);
                    }
                }
            }
            return $ret;
        }
    
        /**
         * returns value of a column
         *
         * @throws InvalidArgumentException if column could not be found
         * @throws BadMethodCallException if getter for additional field could not be found
         * @param string $field
         * @return null|string|SimpleORMapCollection
         */
        public function getValue($field)
        {
            $field = strtolower($field);
    
            // No value defined, throw exception
            if (!in_array($field, $this->known_slots())) {
                throw new InvalidArgumentException(static::class . '::'.$field . ' not found.');
            }
    
            // Get value by getter
            if (isset($this->getter_setter_map()[$field]['get'])) {
                return call_user_func([$this, $this->getter_setter_map()[$field]['get']]);
            }
    
            // Get value from content
            if (array_key_exists($field, $this->content)) {
                return $this->content[$field];
            }
    
            // Get value from relation
            if (array_key_exists($field, $this->relations)) {
                $this->initRelation($field);
                return $this->relations[$field];
            }
    
            // Get value from additional_field
            if (isset($this->additional_fields()[$field]['get'])) {
                // Getter is defined as a closure
                if ($this->additional_fields()[$field]['get'] instanceof Closure) {
                    return call_user_func_array($this->additional_fields()[$field]['get'], [$this, $field]);
                }
    
                // Getter is defined as a method of this object
                return call_user_func([$this, $this->additional_fields()[$field]['get']], $field);
            }
    
            // No value found, throw exception
            throw new RuntimeException('No value could be found for ' . static::class . '::' . $field);
        }
    
        /**
         * gets a value from a related object
         * only possible, if the relation has cardinality 1
         * e.g. 'has_one' or 'belongs_to'
         *
         * @param string $relation name of relation
         * @param string $field name of column
         * @throws InvalidArgumentException if no relation with given name is found
         * @return mixed the value from the related object
         */
        function getRelationValue($relation, $field)
        {
            $field = strtolower($field);
            $options = $this->getRelationOptions($relation);
            if ($options['type'] === 'has_one' || $options['type'] === 'belongs_to') {
                return $this->{$relation}->{$field} ?? null;
            } else {
                throw new InvalidArgumentException('Relation ' . $relation . ' not found or not applicable.');
            }
        }
    
        /**
         * returns default value for column
         *
         * @param string $field name of column
         * @return mixed the default value
         */
         function getDefaultValue($field)
         {
             $default_value = null;
             if (!isset($this->default_values()[$field])) {
                 if (!in_array($field, $this->pk())) {
                     $meta = $this->db_fields()[$field];
                     if (isset($meta['default'])) {
                         $default_value = $meta['default'];
                     } elseif ($meta['null'] == 'NO') {
                         if (strpos($meta['type'], 'text') !== false || strpos($meta['type'], 'char') !== false) {
                             $default_value = '';
                         }
                         if (strpos($meta['type'], 'int') !== false) {
                             $default_value = '0';
                         }
                     }
                 }
             } else {
                 $default_value = $this->default_values()[$field];
             }
             return $default_value;
         }
    
        /**
         * sets value of a column
         *
         * @throws InvalidArgumentException if column could not be found
         * @throws BadMethodCallException if setter for additional field could not be found
         * @param string $field
         * @param mixed $value
         * @return string
         */
         function setValue($field, $value)
         {
             $field = strtolower($field);
             $ret = false;
             if (in_array($field, $this->known_slots())) {
                 if (isset($this->getter_setter_map()[$field]['set'])) {
                     return call_user_func([$this, $this->getter_setter_map()[$field]['set']], $value);
                 }
                 if (array_key_exists($field, $this->content)) {
                     if (array_key_exists($field, $this->serialized_fields())) {
                         $ret = $this->setSerializedValue($field, $value);
                     } elseif ($this->isI18nField($field)) {
                             $ret = $this->setI18nValue($field, $value);
                     } else {
                         $ret = ($this->content[$field] = $value);
                     }
                 } elseif (isset($this->additional_fields()[$field]['set'])) {
                     if ($this->additional_fields()[$field]['set'] instanceof Closure) {
                         return call_user_func_array($this->additional_fields()[$field]['set'], [$this, $field, $value]);
                     } else {
                         return call_user_func([$this, $this->additional_fields()[$field]['set']], $field, $value);
                     }
                 } elseif (array_key_exists($field, $this->relations)) {
                     $options = $this->getRelationOptions($field);
                     if ($options['type'] === 'has_one' || $options['type'] === 'belongs_to') {
                         if (is_a($value, $options['class_name'])) {
                             $this->relations[$field] = $value;
                             if ($options['type'] == 'has_one') {
                                 $foreign_key_value = call_user_func($options['assoc_func_params_func'], $this);
                                 call_user_func($options['assoc_foreign_key_setter'], $value, $foreign_key_value);
                             } else {
                                 $assoc_foreign_key_value = call_user_func($options['assoc_foreign_key_getter'], $value, $this);
                                 if ($assoc_foreign_key_value === null) {
                                     throw new InvalidArgumentException(sprintf('trying to set belongs_to object of type: %s, but assoc_foreign_key: %s is null', get_class($value), $options['assoc_foreign_key']));
                                 }
                                 $this->setValue($options['foreign_key'], $assoc_foreign_key_value);
                             }
                         } else {
                             throw new InvalidArgumentException(sprintf('relation %s expects object of type: %s', $field, $options['class_name']));
                         }
                     }
                     if ($options['type'] == 'has_many' || $options['type'] == 'has_and_belongs_to_many') {
                         if (is_array($value) || $value instanceof Traversable) {
                             $new_ids = [];
                             $old_ids = $this->{$field}->pluck('id');
                             foreach ($value as $current) {
                                 if (!is_a($current, $options['class_name'])) {
                                     throw new InvalidArgumentException(sprintf('relation %s expects object of type: %s', $field, $options['class_name']));
                                 }
                                 if ($options['type'] == 'has_many') {
                                     $foreign_key_value = call_user_func($options['assoc_func_params_func'], $this);
                                     call_user_func($options['assoc_foreign_key_setter'], $current, $foreign_key_value);
                                 }
                                 if ($current->id !== null) {
                                     $new_ids[] = $current->id;
                                     $existing = $this->{$field}->find($current->id);
                                     if ($existing) {
                                         $existing->setData($current);
                                     } else {
                                         $this->{$field}->append($current);
                                     }
                                 } else {
                                     $this->{$field}->append($current);
                                 }
                             }
                             foreach (array_diff($old_ids, $new_ids) as $to_delete) {
                                 $this->{$field}->unsetByPK($to_delete);
                             }
                         } else {
                             throw new InvalidArgumentException(sprintf('relation %s expects collection or array of objects of type: %s', $field, $options['class_name']));
                         }
                     }
                 }
             } else {
                 throw new InvalidArgumentException(get_class($this) . '::'. $field . ' not found.');
             }
             return $ret;
         }
    
        /**
         * magic method for dynamic properties
         *
         * @throws InvalidArgumentException if column could not be found
         * @throws BadMethodCallException if getter for additional field could not be found
         * @param string $field the column or additional field
         * @return null|string|SimpleORMapCollection
         */
        function __get($field)
        {
            return $this->getValue($field);
        }
        /**
         * magic method for dynamic properties
         *
         * @throws InvalidArgumentException if column could not be found
         * @throws BadMethodCallException if setter for additional field could not be found
         * @param string $field
         * @param string $value
         * @return string
         */
        function __set($field, $value)
        {
            return $this->setValue($field, $value);
        }
        /**
         * magic method for dynamic properties
         *
         * @param string $field
         * @return bool
         */
        function __isset($field)
        {
            $field = strtolower($field);
            if (in_array($field, $this->known_slots())) {
                $value = $this->getValue($field);
                return $value instanceOf SimpleORMapCollection ? (bool)count($value) : !is_null($value);
            } else {
                return false;
            }
        }
        /**
         * ArrayAccess: Check whether the given offset exists.
         *
         * @param string $offset
         * @return bool
         *
         * @todo Add bool return type when Stud.IP requires PHP8 minimal
         */
        #[ReturnTypeWillChange]
        public function offsetExists($offset)
        {
            return $this->__isset($offset);
        }
    
        /**
         * ArrayAccess: Get the value at the given offset.
         *
         * @throws InvalidArgumentException if column could not be found
         * @throws BadMethodCallException if getter for additional field could not be found
         * @param string $offset the column or additional field
         * @return null|string|SimpleORMapCollection
         *
         * @todo Add mixed return type when Stud.IP requires PHP8 minimal
         */
        #[ReturnTypeWillChange]
        public function offsetGet($offset)
        {
            return $this->getValue($offset);
        }
    
        /**
         * ArrayAccess: Set the value at the given offset.
         *
         * @throws InvalidArgumentException if column could not be found
         * @throws BadMethodCallException if setter for additional field could not be found
         * @param string $offset
         * @param mixed $value
         * @return void
         *
         * @todo Add void return type when Stud.IP requires PHP8 minimal
         */
        #[ReturnTypeWillChange]
        public function offsetSet($offset, $value)
        {
            $this->setValue($offset, $value);
        }
        /**
         * ArrayAccess: unset the value at the given offset (not applicable)
         *
         * @param string $offset
         * @return void
         *
         * @todo Add void return type when Stud.IP requires PHP8 minimal
         */
        #[ReturnTypeWillChange]
        public function offsetUnset($offset)
        {
    
        }
        /**
         * IteratorAggregate
         *
         * @return ArrayIterator
         *
         * @todo Add Traversable return type when Stud.IP requires PHP8 minimal
         */
        #[ReturnTypeWillChange]
        public function getIterator()
        {
            return new ArrayIterator($this->toArray());
        }
        /**
         * Countable
         *
         * @return int
         *
         * @todo Add int return type when Stud.IP requires PHP8 minimal
         */
        #[ReturnTypeWillChange]
        public function count()
        {
            return count($this->known_slots()) - count($this->relations);
        }
    
        /**
         * check if given column exists in table
         * @param string $field
         * @return boolean
         */
        function isField($field)
        {
            $field = strtolower($field);
            return isset($this->db_fields()[$field]);
        }
    
        /**
         * check if given relation exists in this class
         * @param string $field
         * @return boolean
         */
        function isRelation($field)
        {
            $field = strtolower($field);
            return array_key_exists($field, $this->relations);
        }
    
        /**
         * check if given column is additional
         * @param string $field
         * @return boolean
         */
        function isAdditionalField($field)
        {
            $field = strtolower($field);
            return isset($this->additional_fields()[$field]);
        }
    
        /**
         * check if given column is an alias
         * @param string $field
         * @return boolean
         */
        function isAliasField($field)
        {
            $field = strtolower($field);
            return isset($this->alias_fields()[$field]);
        }
    
        /**
         * check if given column is a multi-language field
         * @param string $field
         * @return boolean
         */
        function isI18nField($field)
        {
            $field = strtolower($field);
            return isset($this->i18n_fields()[$field]);
        }
    
        /**
         * set multiple column values
         * if second param is set, existing data in object will be
         * discarded and dirty state is cleared,
         * else new data overrides old data
         *
         * @param ?iterable $data assoc array
         * @param ?boolean $reset existing data in object will be discarded
         * @return int|bool number of columns changed
         */
        function setData($data, $reset = false)
        {
            $count = 0;
            if ($reset) {
                if ($this->applyCallbacks('before_initialize') === false) {
                    return false;
                }
                $this->initializeContent();
            }
            if (is_iterable($data)) {
                foreach($data as $key => $value) {
                    $key = strtolower($key);
                    if (isset($this->db_fields()[$key])
                        || isset($this->alias_fields()[$key])
                        || isset($this->additional_fields()[$key]['set'])
                    ) {
                        $this->setValue($key, $value);
                        ++$count;
                    }
                }
            }
            if ($reset) {
                $this->applyCallbacks('after_initialize');
            }
            return $count;
        }
    
        /**
         * check if object exists in database
         * @return boolean
         */
        function isNew()
        {
            return $this->is_new;
        }
    
        /**
         * check if object was deleted
         *
         * @return boolean
         */
        function isDeleted()
        {
            return $this->is_deleted;
        }
    
        /**
         * set object to new state
         * @param boolean $is_new
         * @return boolean
         */
        function setNew($is_new)
        {
            return $this->is_new = $is_new;
        }
    
        /**
         * returns sql clause with current table and pk
         * @throws UnexpectedValueException if the primary key is incomplete
         * @return boolean|array<string>
         */
        function getWhereQuery()
        {
            $where_query = null;
            $pk_not_set = [];
            foreach ($this->pk() as $key) {
                $pk = $this->content_db[$key] ?? $this->content[$key] ?? null;
                if (isset($pk)) {
                    $where_query[] = "`{$this->db_table()}`.`{$key}` = "  . DBManager::get()->quote($pk);
                } else {
                    $pk_not_set[] = $key;
                }
            }
            if (!$where_query || count($pk_not_set)){
                if ($this->isNew()) {
                    return false;
                } else {
                    throw new UnexpectedValueException(sprintf("primary key incomplete: %s must not be null", join(',',$pk_not_set)));
                }
            }
            return $where_query;
        }
    
        /**
         * restore entry from database
         * @return boolean
         */
        function restore()
        {
            $where_query = $this->getWhereQuery();
            $id = $this->getId();
            if ($where_query) {
                if ($this->applyCallbacks('before_initialize') === false) {
                    return false;
                }
                $this->initializeContent();
                $query = "SELECT * FROM `{$this->db_table()}` WHERE "
                        . join(" AND ", $where_query);
                $st = DBManager::get()->prepare($query);
                $st->execute();
                $st->setFetchMode(PDO::FETCH_INTO , $this);
                if ($st->fetch()) {
                    $this->setNew(false);
                    $this->applyCallbacks('after_initialize');
                    return true;
                }
            }
            $this->setData([], true);
            $this->setNew(true);
            if (isset($id)) {
                $this->setId($id);
            }
            return false;
        }
    
        /**
         * store entry in database
         *
         * @throws UnexpectedValueException if there are forbidden NULL values
         * @return number|boolean
         */
        function store()
        {
            // Set id or prepare setting of id
            if ($this->isNew() && $this->getId() === null) {
                // Explicitly set id to 0 if auto increment pk is null
                if ($this->hasAutoIncrementColumn()) {
                    $this->setId(0);
                } else {
                    $this->setId($this->getNewId());
                }
            }
    
            if ($this->applyCallbacks('before_store') === false) {
                return false;
            }
    
            $ret = 0;
    
            if (!$this->isDeleted() && ($this->isDirty() || $this->isNew())) {
                $callback = $this->isNew() ? 'before_create' : 'before_update';
                if ($this->applyCallbacks($callback) === false) {
                    return false;
                }
    
                // Collect i18n contents
                $i18ncontent = [];
                foreach (array_keys($this->i18n_fields()) as $field) {
                    if ($this->content[$field] instanceof I18NString) {
                        $i18ncontent[$field] = $this->content[$field];
                        $this->content[$field] = $this->content[$field]->original();
                        $this->content_db[$field] = $this->content_db[$field]->original();
                    }
                }
    
                // Create sql data assignment chunks
                foreach ($this->db_fields() as $field => $meta) {
                    $value = $this->content[$field];
                    if ($field == 'chdate' && !$this->isFieldDirty($field) && $this->isDirty()) {
                        $value = time();
                    }
                    if ($field == 'mkdate') {
                        if ($this->isNew()) {
                            if (!$this->isFieldDirty($field)) {
                                $value = time();
                            }
                        } else {
                            continue;
                        }
                    }
                    if ($value === null && $meta['null'] == 'NO') {
                        throw new UnexpectedValueException($this->db_table() . '.' . $field . ' must not be null.');
                    }
                    if (is_float($value)) {
                        $value = str_replace(',', '.', $value);
                    }
                    $this->content[$field] = $value;
                    $query_part[] = "`$field` = " . DBManager::get()->quote($value) . " ";
                }
    
                // Create store query
                if (!$this->isNew()) {
                    $where_query = $this->getWhereQuery();
                    $query = "UPDATE `{$this->db_table()}` SET "
                        . implode(',', $query_part);
                    $query .= " WHERE " . join(" AND ", $where_query);
                } else {
                    $query = "INSERT INTO `{$this->db_table()}` SET "
                        . implode(',', $query_part);
                }
                $ret = DBManager::get()->exec($query);
    
                // Retrieve generated id from database if pk is an auto increment
                // column
                if ($this->isNew()) {
                    if ($this->hasAutoIncrementColumn() && !$this->getId()) {
                        $this->setId(DBManager::get()->lastInsertId());
                    }
                }
    
                // Store i18n contents
                foreach ($i18ncontent as $field => $one) {
                    $meta = [
                        'object_id' => $this->getId(),
                        'table'     => $this->db_table(),
                        'field'     => $field
                    ];
                    $one->setMetadata($meta);
                    $one->storeTranslations();
                    if (!$this->content[$field] instanceof I18NString) {
                        $this->content[$field] = $one;
                        $this->content_db[$field] = clone $one;
                    }
                }
    
                // Apply callbacks
                $this->applyCallbacks($this->isNew() ? 'after_create' : 'after_update');
            }
            $rel_ret = $this->storeRelations();
    
            $this->applyCallbacks('after_store');
    
            if ($ret || $rel_ret) {
                $this->restore();
            }
            return $ret + $rel_ret;
        }
    
        /**
         * sends a store message to all initialized related objects
         * if a relation has a callback for 'on_store' configured, the callback
         * is instead invoked
         *
         * @param null|array|string $only_these
         * @return int|false number addition of all return values, false if none was called
         */
        protected function storeRelations($only_these = null)
        {
            $ret = false;
            if (is_string($only_these)) {
                $only_these = words($only_these);
            }
            $relations = array_keys($this->relations);
            if (is_array($only_these)) {
                $only_these = array_filter(array_map(function ($s) {
                    return is_string($s) ? strtolower($s) : null;
                }, $only_these));
                $relations = array_intersect($only_these, $relations);
            }
            foreach ($relations as $relation) {
                $options = $this->getRelationOptions($relation);
                if (isset($options['on_store']) &&
                ($options['type'] === 'has_one' ||
                $options['type'] === 'has_many' ||
                $options['type'] === 'has_and_belongs_to_many')) {
                    if ($options['on_store'] instanceof Closure) {
                        $ret += call_user_func($options['on_store'], $this, $relation);
                    } elseif (isset($this->relations[$relation])) {
                        $foreign_key_value = call_user_func($options['assoc_func_params_func'], $this);
                        if ($options['type'] === 'has_one') {
                            call_user_func($options['assoc_foreign_key_setter'], $this->{$relation}, $foreign_key_value);
                            $ret = call_user_func([$this->{$relation}, 'store']);
                        } elseif ($options['type'] === 'has_many') {
                            foreach ($this->{$relation} as $r) {
                                call_user_func($options['assoc_foreign_key_setter'], $r, $foreign_key_value);
                            }
                            $ret += array_sum(call_user_func([$this->{$relation}, 'sendMessage'], 'store'));
                            $ret += array_sum(call_user_func([$this->{$relation}->getDeleted(), 'sendMessage'], 'delete'));
                        } else {
                            call_user_func([$this->{$relation}, 'sendMessage'], 'store');
                            $to_delete = array_filter($this->{$relation}->getDeleted()->pluck($options['assoc_foreign_key']));
                            $to_insert = array_filter($this->{$relation}->pluck($options['assoc_foreign_key']));
                            $sql = "DELETE FROM `" . $options['thru_table'] ."` WHERE `" . $options['thru_key'] ."` = ? AND `" . $options['thru_assoc_key'] . "` = ?";
                            $st = DBManager::get()->prepare($sql);
                            foreach ($to_delete as $one_value) {
                                $st->execute([$foreign_key_value, $one_value]);
                                $ret += $st->rowCount();
                            }
                            $sql = "INSERT IGNORE INTO `" . $options['thru_table'] ."` SET `" . $options['thru_key'] ."` = ?, `" . $options['thru_assoc_key'] . "` = ?";
                            $st = DBManager::get()->prepare($sql);
                            foreach ($to_insert as $one_value) {
                                $st->execute([$foreign_key_value, $one_value]);
                                $ret += $st->rowCount();
                            }
                        }
                    }
                }
            }
            return $ret;
        }
    
        /**
         * set chdate column to current timestamp
         * @return boolean
         */
        function triggerChdate()
        {
            if ($this->db_fields()['chdate']) {
                $this->content['chdate'] = time();
                if ($where_query = $this->getWhereQuery()) {
                    DBManager::get()->exec("UPDATE `{$this->db_table()}` SET chdate={$this->content['chdate']}
                                WHERE ". join(" AND ", $where_query));
                    return true;
                }
            }
    
            return false;
        }
    
        /**
         * delete entry from database
         * the object is cleared, but is not(!) turned to new state
         * @return bool|int number of deleted rows
         */
        function delete()
        {
            $ret = false;
            if (!$this->isDeleted() && !$this->isNew()) {
                if ($this->applyCallbacks('before_delete') === false) {
                    return false;
                }
                $ret = $this->deleteRelations();
                $where_query = $this->getWhereQuery();
                if ($where_query) {
                    $query = "DELETE FROM `{$this->db_table()}` WHERE "
                            . join(" AND ", $where_query);
                    $ret += DBManager::get()->exec($query);
                }
                $this->is_deleted = true;
                $this->applyCallbacks('after_delete');
    
                // Remove i18n translations
                if (I18N::isEnabled()) {
                    foreach (array_keys($this->i18n_fields()) as $field) {
                        if ($this->content[$field] instanceof I18NString) {
                            $this->content[$field]->removeTranslations();
                        }
                    }
                }
            }
            $this->setData([], true);
            return $ret;
        }
    
        /**
         * sends a delete message to all related objects
         * if a relation has a callback for 'on_delete' configured, the callback
         * is invoked instead
         *
         * @return bool|int addition of all return values, false if none was called
         */
        protected function deleteRelations()
        {
            $ret = false;
            foreach (array_keys($this->relations) as $relation) {
                $options = $this->getRelationOptions($relation);
                if (isset($options['on_delete']) &&
                    ($options['type'] === 'has_one' ||
                    $options['type'] === 'has_many' ||
                    $options['type'] === 'has_and_belongs_to_many')) {
                    if ($options['on_delete'] instanceof Closure) {
                        $ret += call_user_func($options['on_delete'], $this, $relation);
                    } else {
                        if ($options['type'] === 'has_one' || $options['type'] === 'has_many') {
                            $this->initRelation($relation);
                            if (isset($this->relations[$relation])) {
                                if ($options['type'] === 'has_one') {
                                    $ret += call_user_func([$this->{$relation}, 'delete']);
                                } elseif ($options['type'] === 'has_many') {
                                    $ret += array_sum(call_user_func([$this->{$relation}, 'sendMessage'], 'delete'));
                                }
                            }
                        } else {
                            $foreign_key_value = call_user_func($options['assoc_func_params_func'], $this);
                            $sql = "DELETE FROM `" . $options['thru_table'] ."` WHERE `" . $options['thru_key'] ."` = ?";
                            $st = DBManager::get()->prepare($sql);
                            $st->execute([$foreign_key_value]);
                            $ret += $st->rowCount();
                        }
                    }
                    $this->relations[$relation] = null;
                }
            }
            return $ret;
        }
    
        /**
         * init internal content arrays with nulls or defaults
         *
         * @throws UnexpectedValueException if there is an unmatched alias
         * @return void
         */
        protected function initializeContent()
        {
            $this->content = [];
            foreach (array_keys($this->db_fields()) as $field) {
                $this->content[$field] = null;
                $this->content_db[$field] = null;
                $this->setValue($field, $this->getDefaultValue($field));
            }
            foreach ($this->alias_fields() as $alias => $field) {
                if (isset($this->db_fields()[$field])) {
                    $this->content[$alias] =& $this->content[$field];
                    $this->content_db[$alias] =& $this->content_db[$field];
                } else {
                    throw new UnexpectedValueException(sprintf('Column %s not found for alias %s', $field, $alias));
                }
            }
            foreach (array_keys($this->relations) as $one) {
                $this->relations[$one] = null;
            }
            $this->additional_data = [];
        }
    
        /**
         * checks if at least one field was modified since last restore
         *
         * @return boolean
         */
        public function isDirty()
        {
            foreach (array_keys($this->db_fields()) as $field) {
                if ($this->isFieldDirty($field)) {
                    return true;
                }
            }
            return false;
        }
    
        /**
         * checks if given field was modified since last restore
         *
         * @param string $field
         * @return boolean
         */
        public function isFieldDirty($field)
        {
            $field = strtolower($field);
            if ($this->content[$field] === null || $this->content_db[$field] === null) {
                return $this->content[$field] !== $this->content_db[$field];
            } else if ($this->content[$field] instanceof I18NString || $this->content_db[$field] instanceof I18NString) {
                return $this->content[$field] != $this->content_db[$field];
            } else {
                return (string)$this->content[$field] !== (string)$this->content_db[$field];
            }
        }
    
        /**
         * reverts value of given field to last restored value
         *
         * @param string $field
         * @return mixed the restored value
         */
        public function revertValue($field)
        {
            $field = strtolower($field);
            return ($this->content[$field] = $this->content_db[$field]);
        }
    
        /**
         * returns unmodified value of given field
         *
         * @param string $field
         * @throws InvalidArgumentException
         * @return mixed
         */
        public function getPristineValue($field)
        {
            $field = strtolower($field);
            if (array_key_exists($field, $this->content_db)) {
                return $this->content_db[$field];
            } else {
                throw new InvalidArgumentException(get_class($this) . '::'. $field . ' not found.');
            }
        }
    
        /**
         * intitalize a relationship and get related record(s)
         *
         * @param string $relation name of relation
         * @throws InvalidArgumentException if the relation does not exists
         * @return void
         */
        public function initRelation($relation)
        {
            if (!array_key_exists($relation, $this->relations)) {
                throw new InvalidArgumentException('Unknown relation: ' . $relation);
            }
            if ($this->relations[$relation] === null) {
                $options = $this->getRelationOptions($relation);
                $to_call = [$options['class_name'], $options['assoc_func']];
                if (!is_callable($to_call)) {
                    throw new RuntimeException('assoc_func: ' . join('::', $to_call) . ' is not callable.' );
                }
                $params = $options['assoc_func_params_func'];
                if ($options['type'] === 'has_many') {
                    $records = function($record) use ($to_call, $params, $options) {
                        $p = (array)$params($record);
                        return call_user_func_array($to_call, array_merge(count($p) ? $p : [null], [$options['order_by'] ?? null]));
                    };
                    $this->relations[$relation] = new SimpleORMapCollection($records, $options, $this);
                } elseif ($options['type'] === 'has_and_belongs_to_many') {
                    $records = function($record) use ($to_call, $params, $options) {$p = (array)$params($record); return call_user_func_array($to_call, array_merge(count($p) ? $p : [null], [$options]));};
                    $this->relations[$relation] = new SimpleORMapCollection($records, $options, $this);
                } else {
                    $p = (array)$params($this);
                    $records = call_user_func_array($to_call, count($p) ? $p : [null]);
                    $result = is_array($records) ? ($records[0] ?? null) : $records;
                    $this->relations[$relation] = $result;
                }
            }
        }
    
        /**
         * clear data for a relationship
         *
         * @param string $relation name of relation
         * @throws InvalidArgumentException if teh relation does not exists
         * @return void
         */
        public function resetRelation($relation)
        {
            if (!array_key_exists($relation, $this->relations)) {
                throw new InvalidArgumentException('Unknown relation: ' . $relation);
            }
            $this->relations[$relation] = null;
        }
    
        /**
         * invoke registered callbacks for given type
         * if one callback returns false the following will not
         * be invoked
         *
         * @param string $type type of callback
         * @return bool return value from last callback
         */
        protected function applyCallbacks($type)
        {
            $ok = true;
            foreach ($this->registered_callbacks()[$type] as $cb) {
                if ($cb instanceof Closure) {
                    $function =  $cb;
                    $params = [$this, $type, $cb];
                } else {
                    $function = [$this, $cb];
                    $params = [$type];
                };
                $ok = call_user_func_array($function, $params);
                if ($ok === false) {
                    break;
                }
            }
            return $ok;
        }
    
        /**
         * register given callback for one or many possible callback types
         * callback param could be a closure or method name of current class
         *
         * @param string|array $types types to register callback for
         * @param callable $cb callback
         * @throws InvalidArgumentException if the callback type is not known
         * @return number of registered callbacks
         */
        protected static function registerCallback($types, $cb)
        {
            trigger_error(__METHOD__ . ' is deprecated. Please use the configuration in configure().', E_USER_DEPRECATED);
    
            $types = is_array($types) ? $types : words($types);
            $reg = 0;
            foreach ($types as $type) {
                if (isset(static::registered_callbacks()[$type])) {
                    $found = array_search($cb, self::$config[static::class]['registered_callbacks'][$type], true);
                    if ($found === false) {
                        self::$config[static::class]['registered_callbacks'][$type][] = $cb;
                        $reg++;
                    }
                } else {
                    throw new InvalidArgumentException('Unknown callback type: ' . $type);
                }
            }
            return $reg;
        }
    
        /**
         * unregister given callback for one or many possible callback types
         *
         * @param string|array $types types to unregister callback for
         * @param mixed $cb
         * @throws InvalidArgumentException if the callback type is not known
         * @return number of unregistered callbacks
         */
        protected static function unregisterCallback($types, $cb)
        {
            trigger_error(__METHOD__ . ' is deprecated. Please use the configuration in configure().', E_USER_DEPRECATED);
    
            $types = is_array($types) ? $types : words($types);
            foreach ($types as $type) {
                if (isset(static::registered_callbacks()[$type])) {
                    $found = array_search($cb, self::$config[static::class]['registered_callbacks'][$type], true);
                    if ($found !== false) {
                        $unreg++;
                        unset(self::$config[static::class]['registered_callbacks'][$type][$found]);
                    }
                } else {
                    throw new InvalidArgumentException('Unknown callback type: ' . $type);
                }
            }
            return $unreg;
        }
    
        /**
         * default callback used to map specific callbacks to NotificationCenter
         *
         * @param string $cb_type callback type
         * @return void|boolean
         */
        protected function cbNotificationMapper($cb_type)
        {
            if (isset($this->notification_map()[$cb_type])) {
                try {
                    foreach(words($this->notification_map()[$cb_type]) as $notification) {
                        NotificationCenter::postNotification($notification, $this);
                    }
                } catch (NotificationVetoException $e) {
                    return false;
                }
            }
        }
    
        /**
         * default callback used to map specific callbacks to NotificationCenter
         *
         * @param string $cb_type callback type
         * @return void|boolean
         */
        protected function cbAfterInitialize($cb_type)
        {
            foreach (array_keys($this->db_fields()) as $field) {
                if (is_object($this->content[$field])) {
                    $this->content_db[$field] = clone $this->content[$field];
                } else {
                    $this->content_db[$field] = $this->content[$field];
                }
            }
        }
    
        /**
         * default setter used to proxy serialized fields with
         * ArrayObjects
         *
         * @param string $field column name
         * @param mixed $value value
         * @return mixed
         */
         protected function setSerializedValue($field, $value)
         {
             $object_type = $this->serialized_fields()[$field];
             if (is_null($value) || $value instanceof $object_type) {
                 $this->content[$field] = $value;
             } else {
                 $this->content[$field] = new $object_type($value);
             }
             return $this->content[$field];
         }
    
        /**
         * default setter used to proxy I18N fields with
         * I18NString
         *
         * @param string $field column name
         * @param mixed $value value
         * @return mixed
         */
        protected function setI18nValue($field, $value)
        {
            $meta = ['object_id' => $this->getId(),
                     'table'     => $this->db_table(),
                     'field'     => $field];
            if ($value instanceof I18NString) {
                $value->setMetadata($meta);
                $this->content[$field] = $value;
            } else {
                $this->content[$field] = new I18NString($value, null, $meta);
            }
            return $this->content[$field];
        }
    
         /**
          * Cleans up this object. This essentially reset all relations of
          * this object and marks them as unused so that the garbage collector may
          * remove the objects.
          *
          * Use this function when you ran into memory problems and need to free
          * some memory;
          *
          * @return void
          */
         public function cleanup()
         {
             foreach ($this->relations as $relation => $object) {
                 if ($object instanceof SimpleORMap || $object instanceof SimpleORMapCollection) {
                     $this->relations[$relation]->cleanup();
                 }
                 $this->resetRelation($relation);
             }
         }
    }