Method populateState

/**
 * Method to auto-populate the model state.
 *
 * This method should only be called once per instantiation and is designed
 * to be called on the first call to the getState() method unless the model
 * configuration flag to ignore the request is set.
 *
 * Note. Calling getState in this method will result in recursion.
 *
 * @param   string  $ordering   An optional ordering field.
 * @param   string  $direction  An optional direction (asc|desc).
 *
 * @return  void
 *
 * @since   1.6
 */
protected function populateState($ordering = null, $direction = null)
{
    // If the context is set, assume that stateful lists are used.
    if ($this->context) {
        $app = Factory::getApplication();
        $inputFilter = InputFilter::getInstance();
        // Receive & set filters
        if ($filters = $app->getUserStateFromRequest($this->context . '.filter', 'filter', array(), 'array')) {
            foreach ($filters as $name => $value) {
                // Exclude if forbidden
                if (!\in_array($name, $this->filterForbiddenList)) {
                    $this->setState('filter.' . $name, $value);
                }
            }
        }
        $limit = 0;
        // Receive & set list options
        if ($list = $app->getUserStateFromRequest($this->context . '.list', 'list', array(), 'array')) {
            foreach ($list as $name => $value) {
                // Exclude if forbidden
                if (!\in_array($name, $this->listForbiddenList)) {
                    // Extra validations
                    switch ($name) {
                        case 'fullordering':
                            $orderingParts = explode(' ', $value);
                            if (\count($orderingParts) >= 2) {
                                // Latest part will be considered the direction
                                $fullDirection = end($orderingParts);
                                if (\in_array(strtoupper($fullDirection), array('ASC', 'DESC', ''))) {
                                    $this->setState('list.direction', $fullDirection);
                                } else {
                                    $this->setState('list.direction', $direction);
                                    // Fallback to the default value
                                    $value = $ordering . ' ' . $direction;
                                }
                                unset($orderingParts[\count($orderingParts) - 1]);
                                // The rest will be the ordering
                                $fullOrdering = implode(' ', $orderingParts);
                                if (\in_array($fullOrdering, $this->filter_fields)) {
                                    $this->setState('list.ordering', $fullOrdering);
                                } else {
                                    $this->setState('list.ordering', $ordering);
                                    // Fallback to the default value
                                    $value = $ordering . ' ' . $direction;
                                }
                            } else {
                                $this->setState('list.ordering', $ordering);
                                $this->setState('list.direction', $direction);
                                // Fallback to the default value
                                $value = $ordering . ' ' . $direction;
                            }
                            break;
                        case 'ordering':
                            if (!\in_array($value, $this->filter_fields)) {
                                $value = $ordering;
                            }
                            break;
                        case 'direction':
                            if (!\in_array(strtoupper($value), array('ASC', 'DESC', ''))) {
                                $value = $direction;
                            }
                            break;
                        case 'limit':
                            $value = $inputFilter->clean($value, 'int');
                            $limit = $value;
                            break;
                        case 'select':
                            $explodedValue = explode(',', $value);
                            foreach ($explodedValue as &$field) {
                                $field = $inputFilter->clean($field, 'cmd');
                            }
                            $value = implode(',', $explodedValue);
                            break;
                    }
                    $this->setState('list.' . $name, $value);
                }
            }
        } else {
            // Keep B/C for components previous to jform forms for filters
            // Pre-fill the limits
            $limit = $app->getUserStateFromRequest('global.list.limit', 'limit', $app->get('list_limit'), 'uint');
            $this->setState('list.limit', $limit);
            // Check if the ordering field is in the allowed list, otherwise use the incoming value.
            $value = $app->getUserStateFromRequest($this->context . '.ordercol', 'filter_order', $ordering);
            if (!\in_array($value, $this->filter_fields)) {
                $value = $ordering;
                $app->setUserState($this->context . '.ordercol', $value);
            }
            $this->setState('list.ordering', $value);
            // Check if the ordering direction is valid, otherwise use the incoming value.
            $value = $app->getUserStateFromRequest($this->context . '.orderdirn', 'filter_order_Dir', $direction);
            if (!$value || !\in_array(strtoupper($value), array('ASC', 'DESC', ''))) {
                $value = $direction;
                $app->setUserState($this->context . '.orderdirn', $value);
            }
            $this->setState('list.direction', $value);
        }
        // Support old ordering field
        $oldOrdering = $app->input->get('filter_order');
        if (!empty($oldOrdering) && \in_array($oldOrdering, $this->filter_fields)) {
            $this->setState('list.ordering', $oldOrdering);
        }
        // Support old direction field
        $oldDirection = $app->input->get('filter_order_Dir');
        if (!empty($oldDirection) && \in_array(strtoupper($oldDirection), array('ASC', 'DESC', ''))) {
            $this->setState('list.direction', $oldDirection);
        }
        $value = $app->getUserStateFromRequest($this->context . '.limitstart', 'limitstart', 0, 'int');
        $limitstart = $limit != 0 ? floor($value / $limit) * $limit : 0;
        $this->setState('list.start', $limitstart);
    } else {
        $this->setState('list.start', 0);
        $this->setState('list.limit', 0);
    }
}