<?php
/**
 * @copyright	Copyright (C) 2005 - 2012 Open Source Matters, Inc. All rights reserved.
 * @license		GNU General Public License version 2 or later; see LICENSE.txt
 */

// No direct access.
defined('_JEXEC') or die;

jimport('joomla.application.component.modeladmin');

/**
 * User view level model.
 *
 * @package		Joomla.Administrator
 * @subpackage	com_users
 * @since		1.6
 */
class UsersModelLevel extends JModelAdmin
{
	/**
	 * @var	array	A list of the access levels in use.
	 * @since	1.6
	 */
	protected $levelsInUse = null;

	/**
	 * Method to test whether a record can be deleted.
	 *
	 * @param	object	$record	A record object.
	 *
	 * @return	boolean	True if allowed to delete the record. Defaults to the permission set in the component.
	 * @since	1.6
	 */
	protected function canDelete($record)
	{
		// Check if the access level is being used by any content.
		if ($this->levelsInUse === null) {
			// Populate the list once.
			$this->levelsInUse = array();

			$db		= $this->getDbo();
			$query	= $db->getQuery(true)
				->select('DISTINCT access');
				// from is added dynamically

			// Get all the tables and then all the fields
			$tables = $db->getTableList();
			$fields = $db->getTableFields($tables);
			$prefix = $db->getPrefix();

			foreach ($tables as $table)
			{
				// We are looking for the access field.  If custom tables are using something other
				// than the 'access' field they are on their own unfortunately.
				// Also make sure the table prefix matches the live db prefix (eg, it is not a "bak_" table)
				if ((strpos($table, $prefix) === 0) && (isset($fields[$table]['access']))) {
					// Lookup the distinct values of the field.
					$query->clear('from')
						->from($db->quoteName($table));
					$db->setQuery($query);

					$values = $db->loadColumn();
					$error	= $db->getErrorMsg();

					// Check for DB error.
					if ($error) {
						$this->setError($error);

						return false;
					}

					$this->levelsInUse = array_merge($this->levelsInUse, $values);

					// TODO Could assemble an array of the tables used by each view level list those,
					// giving the user a clue in the error where to look.
				}
			}

			// Get uniques.
			$this->levelsInUse = array_unique($this->levelsInUse);

			// Ok, after all that we are ready to check the record :)
		}

		if (in_array($record->id, $this->levelsInUse)) {
			$this->setError(JText::sprintf('COM_USERS_ERROR_VIEW_LEVEL_IN_USE', $record->id, $record->title));

			return false;
		}

		return parent::canDelete($record);
	}

	/**
	 * Returns a reference to the a Table object, always creating it.
	 *
	 * @param	type	The table type to instantiate
	 * @param	string	A prefix for the table class name. Optional.
	 * @param	array	Configuration array for model. Optional.
	 * @return	JTable	A database object
	 * @since	1.6
	*/
	public function getTable($type = 'Viewlevel', $prefix = 'JTable', $config = array())
	{
		$return = JTable::getInstance($type, $prefix, $config);

		return $return;
	}

	/**
	 * Method to get a single record.
	 *
	 * @param	integer	The id of the primary key.
	 * @return	mixed	Object on success, false on failure.
	 * @since	1.6
	 */
	public function getItem($pk = null)
	{
		$result = parent::getItem($pk);

		// Convert the params field to an array.
		$result->rules = json_decode($result->rules);

		return $result;
	}

	/**
	 * Method to get the record form.
	 *
	 * @param	array	$data		An optional array of data for the form to interogate.
	 * @param	boolean	$loadData	True if the form is to load its own data (default case), false if not.
	 * @return	JForm	A JForm object on success, false on failure
	 * @since	1.6
	 */
	public function getForm($data = array(), $loadData = true)
	{
		// Initialise variables.
		$app = JFactory::getApplication();

		// Get the form.
		$form = $this->loadForm('com_users.level', 'level', array('control' => 'jform', 'load_data' => $loadData));

		if (empty($form)) {
			return false;
		}

		return $form;
	}

	/**
	 * Method to get the data that should be injected in the form.
	 *
	 * @return	mixed	The data for the form.
	 * @since	1.6
	 */
	protected function loadFormData()
	{
		// Check the session for previously entered form data.
		$data = JFactory::getApplication()->getUserState('com_users.edit.level.data', array());

		if (empty($data)) {
			$data = $this->getItem();
		}

		return $data;
	}

	/**
	 * Override preprocessForm to load the user plugin group instead of content.
	 *
	 * @param	object	A form object.
	 * @param	mixed	The data expected for the form.
	 * @throws	Exception if there is an error in the form event.
	 * @since	1.6
	 */
	protected function preprocessForm(JForm $form, $data, $groups = '')
	{
		parent::preprocessForm($form, $data, 'user');
	}

	/**
	 * Method to save the form data.
	 *
	 * @param	array	The form data.
	 * @return	boolean	True on success.
	 * @since	1.6
	 */
	public function save($data)
	{
		if (!isset($data['rules'])) {
			$data['rules']=array();
		}

		return parent::save($data);
	}
}
