<?php

	class EditPickerHelper extends kHelper {


		function getTable($prefix, $temp=false)
		{
			$table_name = $this->Application->getUnitOption($prefix, 'TableName');
			return $temp ? $this->Application->GetTempName($table_name, 'prefix:'.$prefix) : $table_name;
		}

		/**
		 * Applies filter for multiple lists in inp_edit_picker control.
		 * Called from SetCustomQuery of prefix, that contains all available items.
		 *
		 * @param kEvent $event
		 * @param string $storage_field main item's field name, where values are located
		 */
		function applyFilter(&$event, $storage_field)
		{
			if ($event->Special != 'selected' && $event->Special != 'available') {
				return ;
			}

			$object =& $event->getObject();
			/* @var $object kDBList */

			$main_object =& $this->Application->recallObject($event->getEventParam('link_to_prefix'));
			/* @var $main_object kDBItem */

			$selected_items = $main_object->GetDBField($storage_field);
			if ($selected_items) {
				$filter_type = $event->Special == 'selected' ? 'IN' : 'NOT IN';
				$selected_items = explode('|', substr($selected_items, 1, -1));
				$filter_clause = $object->IDField.' '.$filter_type.' ('.implode(',', $selected_items).')';
			}
			else {
				$filter_clause = ($event->Special == 'selected') ? 'FALSE' : 'TRUE';
			}

			$object->addFilter('edit_picker_filter', $filter_clause);
		}

		/**
		 * Loads selected values from sub_prefix to main item virtual field.
		 * Called from OnAfterItemLoad of main prefix.
		 *
		 * @param kEvent $event
		 * @param string $store_field main item's field name, to store values into
		 * @param string $source_field prefix and it's field used to store info about selected items (format: prefix.field)
		 */
		function LoadValues(&$event, $store_field, $source_field)
		{
			$object =& $event->getObject();
			/* @var $object kDBItem */

			list ($sub_prefix, $sub_prefix_field) = explode('.', $source_field);
			$foreign_key = $this->Application->getUnitOption($sub_prefix, 'ForeignKey');

			$sql = 'SELECT '.$sub_prefix_field.'
					FROM '.$this->getTable($sub_prefix, $object->IsTempTable()).'
					WHERE '.$foreign_key.' = '.$object->GetID();
			$selected_items = array_unique($this->Conn->GetCol($sql));

			$object->SetDBField($store_field, $selected_items ? '|'.implode('|', $selected_items).'|' : '');
		}
	}

?>