<?php
  
  namespace OC\Setup;
  
  class OCI extends AbstractDatabase {
  	public $dbprettyname = 'Oracle';
  
  	protected $dbtablespace;
  
  	public function initialize($config) {
  		parent::initialize($config);
  		if (array_key_exists('dbtablespace', $config)) {
  			$this->dbtablespace = $config['dbtablespace'];
  		} else {
  			$this->dbtablespace = 'USERS';
  		}
  		\OC_Config::setValue('dbtablespace', $this->dbtablespace);
  	}
  
  	public function setupDatabase($username) {
  		$e_host = addslashes($this->dbhost);
  		$e_dbname = addslashes($this->dbname);
  		//check if the database user has admin right
  		if ($e_host == '') {
  			$easy_connect_string = $e_dbname; // use dbname as easy connect name
  		} else {
  			$easy_connect_string = '//'.$e_host.'/'.$e_dbname;
  		}
  		\OC_Log::write('setup oracle', 'connect string: ' . $easy_connect_string, \OC_Log::DEBUG);
  		$connection = @oci_connect($this->dbuser, $this->dbpassword, $easy_connect_string);
  		if(!$connection) {
  			$errorMessage = $this->getLastError();
  			if ($errorMessage) {
  				throw new \DatabaseSetupException($this->trans->t('Oracle connection could not be established'),
  				$errorMessage.' Check environment: ORACLE_HOME='.getenv('ORACLE_HOME')
  							.' ORACLE_SID='.getenv('ORACLE_SID')
  							.' LD_LIBRARY_PATH='.getenv('LD_LIBRARY_PATH')
  							.' NLS_LANG='.getenv('NLS_LANG')
  							.' tnsnames.ora is '.(is_readable(getenv('ORACLE_HOME').'/network/admin/tnsnames.ora')?'':'not ').'readable');
  			}
  			throw new \DatabaseSetupException($this->trans->t('Oracle username and/or password not valid'),
  					'Check environment: ORACLE_HOME='.getenv('ORACLE_HOME')
  							.' ORACLE_SID='.getenv('ORACLE_SID')
  							.' LD_LIBRARY_PATH='.getenv('LD_LIBRARY_PATH')
  							.' NLS_LANG='.getenv('NLS_LANG')
  							.' tnsnames.ora is '.(is_readable(getenv('ORACLE_HOME').'/network/admin/tnsnames.ora')?'':'not ').'readable');
  		}
  		//check for roles creation rights in oracle
  
  		$query='SELECT count(*) FROM user_role_privs, role_sys_privs'
  			." WHERE user_role_privs.granted_role = role_sys_privs.role AND privilege = 'CREATE ROLE'";
  		$stmt = oci_parse($connection, $query);
  		if (!$stmt) {
  			$entry = $this->trans->t('DB Error: "%s"', array($this->getLastError($connection))) . '<br />';
  			$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  			\OC_Log::write('setup.oci', $entry, \OC_Log::WARN);
  		}
  		$result = oci_execute($stmt);
  		if($result) {
  			$row = oci_fetch_row($stmt);
  		}
  		if($result and $row[0] > 0) {
  			//use the admin login data for the new database user
  
  			//add prefix to the oracle user name to prevent collisions
  			$this->dbuser='oc_'.$username;
  			//create a new password so we don't need to store the admin config in the config file
  			$this->dbpassword=\OC_Util::generateRandomBytes(30);
  
  			//oracle passwords are treated as identifiers:
  			//  must start with alphanumeric char
  			//  needs to be shortened to 30 bytes, as the two " needed to escape the identifier count towards the identifier length.
  			$this->dbpassword=substr($this->dbpassword, 0, 30);
  
  			$this->createDBUser($connection);
  
  			\OC_Config::setValue('dbuser', $this->dbuser);
  			\OC_Config::setValue('dbname', $this->dbuser);
  			\OC_Config::setValue('dbpassword', $this->dbpassword);
  
  			//create the database not necessary, oracle implies user = schema
  			//$this->createDatabase($this->dbname, $this->dbuser, $connection);
  		} else {
  
  			\OC_Config::setValue('dbuser', $this->dbuser);
  			\OC_Config::setValue('dbname', $this->dbname);
  			\OC_Config::setValue('dbpassword', $this->dbpassword);
  
  			//create the database not necessary, oracle implies user = schema
  			//$this->createDatabase($this->dbname, $this->dbuser, $connection);
  		}
  
  		//FIXME check tablespace exists: select * from user_tablespaces
  
  		// the connection to dbname=oracle is not needed anymore
  		oci_close($connection);
  
  		// connect to the oracle database (schema=$this->dbuser) an check if the schema needs to be filled
  		$this->dbuser = \OC_Config::getValue('dbuser');
  		//$this->dbname = \OC_Config::getValue('dbname');
  		$this->dbpassword = \OC_Config::getValue('dbpassword');
  
  		$e_host = addslashes($this->dbhost);
  		$e_dbname = addslashes($this->dbname);
  
  		if ($e_host == '') {
  			$easy_connect_string = $e_dbname; // use dbname as easy connect name
  		} else {
  			$easy_connect_string = '//'.$e_host.'/'.$e_dbname;
  		}
  		$connection = @oci_connect($this->dbuser, $this->dbpassword, $easy_connect_string);
  		if(!$connection) {
  			throw new \DatabaseSetupException($this->trans->t('Oracle username and/or password not valid'),
  					$this->trans->t('You need to enter either an existing account or the administrator.'));
  		}
  		$query = "SELECT count(*) FROM user_tables WHERE table_name = :un";
  		$stmt = oci_parse($connection, $query);
  		$un = $this->tableprefix.'users';
  		oci_bind_by_name($stmt, ':un', $un);
  		if (!$stmt) {
  			$entry = $this->trans->t('DB Error: "%s"', array($this->getLastError($connection))) . '<br />';
  			$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  			\OC_Log::write('setup.oci', $entry, \OC_Log::WARN);
  		}
  		$result = oci_execute($stmt);
  
  		if($result) {
  			$row = oci_fetch_row($stmt);
  		}
  		if(!$result or $row[0]==0) {
  			\OC_DB::createDbFromStructure($this->dbDefinitionFile);
  		}
  	}
  
  	/**
  	 * @param resource $connection
  	 */
  	private function createDBUser($connection) {
  		$name = $this->dbuser;
  		$password = $this->dbpassword;
  		$query = "SELECT * FROM all_users WHERE USERNAME = :un";
  		$stmt = oci_parse($connection, $query);
  		if (!$stmt) {
  			$entry = $this->trans->t('DB Error: "%s"', array($this->getLastError($connection))) . '<br />';
  			$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  			\OC_Log::write('setup.oci', $entry, \OC_Log::WARN);
  		}
  		oci_bind_by_name($stmt, ':un', $name);
  		$result = oci_execute($stmt);
  		if(!$result) {
  			$entry = $this->trans->t('DB Error: "%s"', array($this->getLastError($connection))) . '<br />';
  			$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  			\OC_Log::write('setup.oci', $entry, \OC_Log::WARN);
  		}
  
  		if(! oci_fetch_row($stmt)) {
  			//user does not exists let's create it :)
  			//password must start with alphabetic character in oracle
  			$query = 'CREATE USER '.$name.' IDENTIFIED BY "'.$password.'" DEFAULT TABLESPACE '.$this->dbtablespace;
  			$stmt = oci_parse($connection, $query);
  			if (!$stmt) {
  				$entry = $this->trans->t('DB Error: "%s"', array($this->getLastError($connection))) . '<br />';
  				$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  				\OC_Log::write('setup.oci', $entry, \OC_Log::WARN);
  			}
  			//oci_bind_by_name($stmt, ':un', $name);
  			$result = oci_execute($stmt);
  			if(!$result) {
  				$entry = $this->trans->t('DB Error: "%s"', array($this->getLastError($connection))) . '<br />';
  				$entry .= $this->trans->t('Offending command was: "%s", name: %s, password: %s',
  					array($query, $name, $password)) . '<br />';
  				\OC_Log::write('setup.oci', $entry, \OC_Log::WARN);
  			}
  		} else { // change password of the existing role
  			$query = "ALTER USER :un IDENTIFIED BY :pw";
  			$stmt = oci_parse($connection, $query);
  			if (!$stmt) {
  				$entry = $this->trans->t('DB Error: "%s"', array($this->getLastError($connection))) . '<br />';
  				$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  				\OC_Log::write('setup.oci', $entry, \OC_Log::WARN);
  			}
  			oci_bind_by_name($stmt, ':un', $name);
  			oci_bind_by_name($stmt, ':pw', $password);
  			$result = oci_execute($stmt);
  			if(!$result) {
  				$entry = $this->trans->t('DB Error: "%s"', array($this->getLastError($connection))) . '<br />';
  				$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  				\OC_Log::write('setup.oci', $entry, \OC_Log::WARN);
  			}
  		}
  		// grant necessary roles
  		$query = 'GRANT CREATE SESSION, CREATE TABLE, CREATE SEQUENCE, CREATE TRIGGER, UNLIMITED TABLESPACE TO '.$name;
  		$stmt = oci_parse($connection, $query);
  		if (!$stmt) {
  			$entry = $this->trans->t('DB Error: "%s"', array($this->getLastError($connection))) . '<br />';
  			$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  			\OC_Log::write('setup.oci', $entry, \OC_Log::WARN);
  		}
  		$result = oci_execute($stmt);
  		if(!$result) {
  			$entry = $this->trans->t('DB Error: "%s"', array($this->getLastError($connection))) . '<br />';
  			$entry .= $this->trans->t('Offending command was: "%s", name: %s, password: %s',
  				array($query, $name, $password)) . '<br />';
  			\OC_Log::write('setup.oci', $entry, \OC_Log::WARN);
  		}
  	}
  
  	/**
  	 * @param resource $connection
  	 * @return string
  	 */
  	protected function getLastError($connection = null) {
  		if ($connection) {
  			$error = oci_error($connection);
  		} else {
  			$error = oci_error();
  		}
  		foreach (array('message', 'code') as $key) {
  			if (isset($error[$key])) {
  				return $error[$key];
  			}
  		}
  		return '';
  	}
  }