<?php
  /**
   * ownCloud
   *
   * @author Frank Karlitschek
   * @author Jakob Sack
   * @copyright 2012 Frank Karlitschek frank@owncloud.org
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
   * License as published by the Free Software Foundation; either
   * version 3 of the License, or any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
   *
   * You should have received a copy of the GNU Affero General Public
   * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
   *
   */
  /*
   *
   * The following SQL statement is just a help for developers and will not be
   * executed!
   *
   * CREATE TABLE  `preferences` (
   * `userid` VARCHAR( 255 ) NOT NULL ,
   * `appid` VARCHAR( 255 ) NOT NULL ,
   * `configkey` VARCHAR( 255 ) NOT NULL ,
   * `configvalue` VARCHAR( 255 ) NOT NULL
   * )
   *
   */

  namespace OC;
  
  use \OC\DB\Connection;

  /**
   * This class provides an easy way for storing user preferences.
   */

  class Preferences {
  	protected $conn;
  
  	public function __construct(Connection $conn) {
  		$this->conn = $conn;
  	}

  	/**
  	 * @brief Get all users using the preferences
  	 * @return array with user ids
  	 *
  	 * This function returns a list of all users that have at least one entry
  	 * in the preferences table.
  	 */

  	public function getUsers() {
  		$query = 'SELECT DISTINCT `userid` FROM `*PREFIX*preferences`';
  		$result = $this->conn->executeQuery( $query );

  
  		$users = array();

  		while( $userid = $result->fetchColumn()) {
  			$users[] = $userid;

  		}
  
  		return $users;
  	}
  
  	/**

  	 * @brief Get all apps of an user

  	 * @param string $user user
  	 * @return array with app ids
  	 *
  	 * This function returns a list of all apps of the user that have at least
  	 * one entry in the preferences table.
  	 */

  	public function getApps( $user ) {
  		$query = 'SELECT DISTINCT `appid` FROM `*PREFIX*preferences` WHERE `userid` = ?';
  		$result = $this->conn->executeQuery( $query, array( $user ) );

  
  		$apps = array();

  		while( $appid = $result->fetchColumn()) {
  			$apps[] = $appid;

  		}
  
  		return $apps;
  	}
  
  	/**
  	 * @brief Get the available keys for an app
  	 * @param string $user user
  	 * @param string $app the app we are looking for
  	 * @return array with key names
  	 *
  	 * This function gets all keys of an app of an user. Please note that the
  	 * values are not returned.
  	 */

  	public function getKeys( $user, $app ) {
  		$query = 'SELECT `configkey` FROM `*PREFIX*preferences` WHERE `userid` = ? AND `appid` = ?';
  		$result = $this->conn->executeQuery( $query, array( $user, $app ));

  
  		$keys = array();

  		while( $key = $result->fetchColumn()) {
  			$keys[] = $key;

  		}
  
  		return $keys;
  	}
  
  	/**
  	 * @brief Gets the preference
  	 * @param string $user user
  	 * @param string $app app
  	 * @param string $key key
  	 * @param string $default = null, default value if the key does not exist
  	 * @return string the value or $default
  	 *
  	 * This function gets a value from the preferences table. If the key does
  	 * not exist the default value will be returned
  	 */

  	public function getValue( $user, $app, $key, $default = null ) {

  		// Try to fetch the value, return default if not exists.

  		$query = 'SELECT `configvalue` FROM `*PREFIX*preferences`'
  			.' WHERE `userid` = ? AND `appid` = ? AND `configkey` = ?';
  		$row = $this->conn->fetchAssoc( $query, array( $user, $app, $key ));

  		if($row) {
  			return $row["configvalue"];

  		} else {

  			return $default;
  		}
  	}
  
  	/**
  	 * @brief sets a value in the preferences
  	 * @param string $user user
  	 * @param string $app app
  	 * @param string $key key
  	 * @param string $value value

  	 *
  	 * Adds a value to the preferences. If the key did not exist before, it
  	 * will be added automagically.
  	 */

  	public function setValue( $user, $app, $key, $value ) {

  		// Check if the key does exist

  		$query = 'SELECT COUNT(*) FROM `*PREFIX*preferences`'
  			.' WHERE `userid` = ? AND `appid` = ? AND `configkey` = ?';
  		$count = $this->conn->fetchColumn( $query, array( $user, $app, $key ));
  		$exists = $count > 0;

  
  		if( !$exists ) {

  			$data = array(
  				'userid' => $user,
  				'appid' => $app,
  				'configkey' => $key,
  				'configvalue' => $value,
  			);
  			$this->conn->insert('*PREFIX*preferences', $data);
  		} else {
  			$data = array(
  				'configvalue' => $value,
  			);
  			$where = array(
  				'userid' => $user,
  				'appid' => $app,
  				'configkey' => $key,
  			);
  			$this->conn->update('*PREFIX*preferences', $data, $where);

  		}

  	}
  
  	/**
  	 * @brief Deletes a key
  	 * @param string $user user
  	 * @param string $app app
  	 * @param string $key key

  	 *
  	 * Deletes a key.
  	 */

  	public function deleteKey( $user, $app, $key ) {
  		$where = array(
  			'userid' => $user,
  			'appid' => $app,
  			'configkey' => $key,
  		);
  		$this->conn->delete('*PREFIX*preferences', $where);

  	}
  
  	/**
  	 * @brief Remove app of user from preferences
  	 * @param string $user user
  	 * @param string $app app

  	 *

  	 * Removes all keys in preferences belonging to the app and the user.

  	 */

  	public function deleteApp( $user, $app ) {
  		$where = array(
  			'userid' => $user,
  			'appid' => $app,
  		);
  		$this->conn->delete('*PREFIX*preferences', $where);

  	}
  
  	/**
  	 * @brief Remove user from preferences
  	 * @param string $user user

  	 *

  	 * Removes all keys in preferences belonging to the user.

  	 */

  	public function deleteUser( $user ) {
  		$where = array(
  			'userid' => $user,
  		);
  		$this->conn->delete('*PREFIX*preferences', $where);

  	}
  
  	/**
  	 * @brief Remove app from all users
  	 * @param string $app app

  	 *
  	 * Removes all keys in preferences belonging to the app.
  	 */

  	public function deleteAppFromAllUsers( $app ) {
  		$where = array(
  			'appid' => $app,
  		);
  		$this->conn->delete('*PREFIX*preferences', $where);

  	}
  }

  
  require_once __DIR__.'/legacy/'.basename(__FILE__);