<?php
  
  namespace OC\Setup;
  
  class PostgreSQL extends AbstractDatabase {
  	public $dbprettyname = 'PostgreSQL';
  
  	public function setupDatabase($username) {
  		$e_host = addslashes($this->dbhost);
  		$e_user = addslashes($this->dbuser);
  		$e_password = addslashes($this->dbpassword);
  
  		//check if the database user has admin rights
  		$connection_string = "host='$e_host' dbname=postgres user='$e_user' password='$e_password'";
  		$connection = @pg_connect($connection_string);
  		if(!$connection) {
  			// Try if we can connect to the DB with the specified name
  			$e_dbname = addslashes($this->dbname);
  			$connection_string = "host='$e_host' dbname='$e_dbname' user='$e_user' password='$e_password'";
  			$connection = @pg_connect($connection_string);
  
  			if(!$connection)
  				throw new \DatabaseSetupException($this->trans->t('PostgreSQL username and/or password not valid'),
  						$this->trans->t('You need to enter either an existing account or the administrator.'));
  		}
  		$e_user = pg_escape_string($this->dbuser);
  		//check for roles creation rights in postgresql
  		$query="SELECT 1 FROM pg_roles WHERE rolcreaterole=TRUE AND rolname='$e_user'";
  		$result = pg_query($connection, $query);
  		if($result and pg_num_rows($result) > 0) {
  			//use the admin login data for the new database user
  
  			//add prefix to the postgresql 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);
  
  			$this->createDBUser($connection);
  
  			\OC_Config::setValue('dbuser', $this->dbuser);
  			\OC_Config::setValue('dbpassword', $this->dbpassword);
  
  			//create the database
  			$this->createDatabase($connection);
  		}
  		else {
  			\OC_Config::setValue('dbuser', $this->dbuser);
  			\OC_Config::setValue('dbpassword', $this->dbpassword);
  
  			//create the database
  			$this->createDatabase($connection);
  		}
  
  		// the connection to dbname=postgres is not needed anymore
  		pg_close($connection);
  
  		// connect to the ownCloud database (dbname=$this->dbname) and check if it needs to be filled
  		$this->dbuser = \OC_Config::getValue('dbuser');
  		$this->dbpassword = \OC_Config::getValue('dbpassword');
  
  		$e_host = addslashes($this->dbhost);
  		$e_dbname = addslashes($this->dbname);
  		$e_user = addslashes($this->dbuser);
  		$e_password = addslashes($this->dbpassword);
  
  		$connection_string = "host='$e_host' dbname='$e_dbname' user='$e_user' password='$e_password'";
  		$connection = @pg_connect($connection_string);
  		if(!$connection) {
  			throw new \DatabaseSetupException($this->trans->t('PostgreSQL username and/or password not valid'),
  					$this->trans->t('You need to enter either an existing account or the administrator.'));
  		}
  		$query = "select count(*) FROM pg_class WHERE relname='".$this->tableprefix."users' limit 1";
  		$result = pg_query($connection, $query);
  		if($result) {
  			$row = pg_fetch_row($result);
  		}
  		if(!$result or $row[0]==0) {
  			\OC_DB::createDbFromStructure($this->dbDefinitionFile);
  		}
  	}
  
  	private function createDatabase($connection) {
  		//we cant use OC_BD functions here because we need to connect as the administrative user.
  		$e_name = pg_escape_string($this->dbname);
  		$e_user = pg_escape_string($this->dbuser);
  		$query = "select datname from pg_database where datname = '$e_name'";
  		$result = pg_query($connection, $query);
  		if(!$result) {
  			$entry = $this->trans->t('DB Error: "%s"', array(pg_last_error($connection))) . '<br />';
  			$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  			\OC_Log::write('setup.pg', $entry, \OC_Log::WARN);
  		}
  		if(! pg_fetch_row($result)) {
  			//The database does not exists... let's create it
  			$query = "CREATE DATABASE \"$e_name\" OWNER \"$e_user\"";
  			$result = pg_query($connection, $query);
  			if(!$result) {
  				$entry = $this->trans->t('DB Error: "%s"', array(pg_last_error($connection))) . '<br />';
  				$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  				\OC_Log::write('setup.pg', $entry, \OC_Log::WARN);
  			}
  			else {
  				$query = "REVOKE ALL PRIVILEGES ON DATABASE \"$e_name\" FROM PUBLIC";
  				pg_query($connection, $query);
  			}
  		}
  	}
  
  	private function createDBUser($connection) {
  		$e_name = pg_escape_string($this->dbuser);
  		$e_password = pg_escape_string($this->dbpassword);
  		$query = "select * from pg_roles where rolname='$e_name';";
  		$result = pg_query($connection, $query);
  		if(!$result) {
  			$entry = $this->trans->t('DB Error: "%s"', array(pg_last_error($connection))) . '<br />';
  			$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  			\OC_Log::write('setup.pg', $entry, \OC_Log::WARN);
  		}
  
  		if(! pg_fetch_row($result)) {
  			//user does not exists let's create it :)
  			$query = "CREATE USER \"$e_name\" CREATEDB PASSWORD '$e_password';";
  			$result = pg_query($connection, $query);
  			if(!$result) {
  				$entry = $this->trans->t('DB Error: "%s"', array(pg_last_error($connection))) . '<br />';
  				$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  				\OC_Log::write('setup.pg', $entry, \OC_Log::WARN);
  			}
  		}
  		else { // change password of the existing role
  			$query = "ALTER ROLE \"$e_name\" WITH PASSWORD '$e_password';";
  			$result = pg_query($connection, $query);
  			if(!$result) {
  				$entry = $this->trans->t('DB Error: "%s"', array(pg_last_error($connection))) . '<br />';
  				$entry .= $this->trans->t('Offending command was: "%s"', array($query)) . '<br />';
  				\OC_Log::write('setup.pg', $entry, \OC_Log::WARN);
  			}
  		}
  	}
  }