<?php
/**
 * @package     Joomla.Administrator
 * @subpackage  com_contenthistory
 *
 * @copyright   Copyright (C) 2005 - 2016 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */

defined('_JEXEC') or die;

/**
 * Methods supporting a list of contenthistory records.
 *
 * @since  3.2
 */
class ContenthistoryModelHistory extends JModelList
{
	/**
	 * Constructor.
	 *
	 * @param   array  $config  An optional associative array of configuration settings.
	 *
	 * @see     JControllerLegacy
	 * @since   3.2
	 */
	public function __construct($config = array())
	{
		if (empty($config['filter_fields']))
		{
			$config['filter_fields'] = array(
					'version_id', 'h.version_id',
					'version_note', 'h.version_note',
					'save_date', 'h.save_date',
					'editor_user_id', 'h.editor_user_id',
			);
		}

		parent::__construct($config);
	}

	/**
	 * Method to test whether a record is editable
	 *
	 * @param   JTableContenthistory  $record  A JTable object.
	 *
	 * @return  boolean  True if allowed to edit the record. Defaults to the permission set in the component.
	 *
	 * @since   3.2
	 */
	protected function canEdit($record)
	{
		$result = false;

		if (!empty($record->ucm_type_id))
		{
			// Check that the type id matches the type alias
			$typeAlias = JFactory::getApplication()->input->get('type_alias');

			/** @var JTableContenttype $contentTypeTable */
			$contentTypeTable = JTable::getInstance('Contenttype', 'JTable');

			if ($contentTypeTable->getTypeId($typeAlias) == $record->ucm_type_id)
			{
				/**
				 * Make sure user has edit privileges for this content item. Note that we use edit permissions
				 * for the content item, not delete permissions for the content history row.
				 */
				$user   = JFactory::getUser();
				$result = $user->authorise('core.edit', $typeAlias . '.' . (int) $record->ucm_item_id);
			}

			// Finally try session (this catches edit.own case too)
			if (!$result)
			{
				$contentTypeTable->load($record->ucm_type_id);
				$typeEditables = (array) JFactory::getApplication()->getUserState(str_replace('.', '.edit.', $contentTypeTable->type_alias) . '.id');
				$result = in_array((int) $record->ucm_item_id, $typeEditables);
			}
		}

		return $result;
	}

	/**
	 * Method to test whether a history record can be deleted. Note that we check whether we have edit permissions
	 * for the content item row.
	 *
	 * @param   JTableContenthistory  $record  A JTable object.
	 *
	 * @return  boolean  True if allowed to delete the record. Defaults to the permission set in the component.
	 *
	 * @since   3.6
	 */
	protected function canDelete($record)
	{
		return canEdit($record);
	}

	/**
	 * Method to delete one or more records from content history table.
	 *
	 * @param   array  &$pks  An array of record primary keys.
	 *
	 * @return  boolean  True if successful, false if an error occurs.
	 *
	 * @since   3.2
	 */
	public function delete(&$pks)
	{
		$pks = (array) $pks;
		$table = $this->getTable();

		// Iterate the items to delete each one.
		foreach ($pks as $i => $pk)
		{
			if ($table->load($pk))
			{
				if ($this->canEdit($table))
				{
					if (!$table->delete($pk))
					{
						$this->setError($table->getError());

						return false;
					}
				}
				else
				{
					// Prune items that you can't change.
					unset($pks[$i]);
					$error = $this->getError();

					if ($error)
					{
						JLog::add($error, JLog::WARNING, 'jerror');

						return false;
					}
					else
					{
						JLog::add(JText::_('JLIB_APPLICATION_ERROR_DELETE_NOT_PERMITTED'), JLog::WARNING, 'jerror');

						return false;
					}
				}
			}
			else
			{
				$this->setError($table->getError());

				return false;
			}
		}

		// Clear the component's cache
		$this->cleanCache();

		return true;
	}

	/**
	 * Method to get an array of data items.
	 *
	 * @return  mixed  An array of data items on success, false on failure.
	 *
	 * @since   3.4.5
	 */
	public function getItems()
	{
		$items = parent::getItems();
		$user = JFactory::getUser();

		if ($items === false)
		{
			return false;
		}

		// This should be an array with at least one element
		if (!is_array($items) || !isset($items[0]))
		{
			return $items;
		}

		// Get the content type's record so we can check ACL
		/** @var JTableContenttype $contentTypeTable */
		$contentTypeTable = JTable::getInstance('Contenttype');
		$ucmTypeId        = $items[0]->ucm_type_id;

		if (!$contentTypeTable->load($ucmTypeId))
		{
			// Assume a failure to load the content type means broken data, abort mission
			return false;
		}

		// Access check
		if ($user->authorise('core.edit', $contentTypeTable->type_alias . '.' . (int) $items[0]->ucm_item_id) || $this->canEdit($items[0]))
		{
			return $items;
		}
		else
		{
			$this->setError(JText::_('JERROR_ALERTNOAUTHOR'));

			return false;
		}
	}

	/**
	 * Method to get a table object, load it if necessary.
	 *
	 * @param   string  $type    The table name. Optional.
	 * @param   string  $prefix  The class prefix. Optional.
	 * @param   array   $config  Configuration array for model. Optional.
	 *
	 * @return  JTable  A JTable object
	 *
	 * @since   3.2
	 */
	public function getTable($type = 'Contenthistory', $prefix = 'JTable', $config = array())
	{
		return JTable::getInstance($type, $prefix, $config);
	}

	/**
	 * Method to toggle on and off the keep forever value for one or more records from content history table.
	 *
	 * @param   array  &$pks  An array of record primary keys.
	 *
	 * @return  boolean  True if successful, false if an error occurs.
	 *
	 * @since   3.2
	 */
	public function keep(&$pks)
	{
		$pks = (array) $pks;
		$table = $this->getTable();

		// Iterate the items to delete each one.
		foreach ($pks as $i => $pk)
		{
			if ($table->load($pk))
			{
				if ($this->canEdit($table))
				{
					$table->keep_forever = $table->keep_forever ? 0 : 1;

					if (!$table->store())
					{
						$this->setError($table->getError());

						return false;
					}
				}
				else
				{
					// Prune items that you can't change.
					unset($pks[$i]);
					$error = $this->getError();

					if ($error)
					{
						JLog::add($error, JLog::WARNING, 'jerror');

						return false;
					}
					else
					{
						JLog::add(JText::_('COM_CONTENTHISTORY_ERROR_KEEP_NOT_PERMITTED'), JLog::WARNING, 'jerror');

						return false;
					}
				}
			}
			else
			{
				$this->setError($table->getError());

				return false;
			}
		}

		// Clear the component's cache
		$this->cleanCache();

		return true;
	}

	/**
	 * Method to auto-populate the model state.
	 *
	 * Note. Calling getState in this method will result in recursion.
	 *
	 * @param   string  $ordering   An optional ordering field.
	 * @param   string  $direction  An optional direction (asc|desc).
	 *
	 * @return  void
	 *
	 * @since   3.2
	 */
	protected function populateState($ordering = 'h.save_date', $direction = 'DESC')
	{
		$input = JFactory::getApplication()->input;
		$itemId = $input->get('item_id', 0, 'integer');
		$typeId = $input->get('type_id', 0, 'integer');
		$typeAlias = $input->get('type_alias', '', 'string');

		$this->setState('item_id', $itemId);
		$this->setState('type_id', $typeId);
		$this->setState('type_alias', $typeAlias);
		$this->setState('sha1_hash', $this->getSha1Hash());

		// Load the parameters.
		$params = JComponentHelper::getParams('com_contenthistory');
		$this->setState('params', $params);

		// List state information.
		parent::populateState($ordering, $direction);
	}

	/**
	 * Build an SQL query to load the list data.
	 *
	 * @return  JDatabaseQuery
	 *
	 * @since   3.2
	 */
	protected function getListQuery()
	{
		// Create a new query object.
		$db = $this->getDbo();
		$query = $db->getQuery(true);

		// Select the required fields from the table.
		$query->select(
			$this->getState(
				'list.select',
				'h.version_id, h.ucm_item_id, h.ucm_type_id, h.version_note, h.save_date, h.editor_user_id,' .
				'h.character_count, h.sha1_hash, h.version_data, h.keep_forever'
			)
		)
		->from($db->quoteName('#__ucm_history') . ' AS h')
		->where($db->quoteName('h.ucm_item_id') . ' = ' . (int) $this->getState('item_id'))
		->where($db->quoteName('h.ucm_type_id') . ' = ' . (int) $this->getState('type_id'))

		// Join over the users for the editor
		->select('uc.name AS editor')
		->join('LEFT', '#__users AS uc ON uc.id = h.editor_user_id');

		// Add the list ordering clause.
		$orderCol = $this->state->get('list.ordering');
		$orderDirn = $this->state->get('list.direction');
		$query->order($db->quoteName($orderCol) . $orderDirn);

		return $query;
	}

	/**
	 * Get the sha1 hash value for the current item being edited.
	 *
	 * @return  string  sha1 hash of row data
	 *
	 * @since   3.2
	 */
	protected function getSha1Hash()
	{
		$result = false;
		$typeTable = JTable::getInstance('Contenttype', 'JTable');
		$typeId = JFactory::getApplication()->input->getInteger('type_id', 0);
		$typeTable->load($typeId);
		$typeAliasArray = explode('.', $typeTable->type_alias);
		JTable::addIncludePath(JPATH_ROOT . '/administrator/components/' . $typeAliasArray[0] . '/tables');
		$contentTable = $typeTable->getContentTable();
		$keyValue = JFactory::getApplication()->input->getInteger('item_id', 0);

		if ($contentTable && $contentTable->load($keyValue))
		{
			$helper = new JHelper;

			$dataObject = $helper->getDataObject($contentTable);
			$result = $this->getTable('Contenthistory', 'JTable')->getSha1(json_encode($dataObject), $typeTable);
		}

		return $result;
	}
}
