class DatabaseTasks_pgsql

class DatabaseTasks_pgsql extends DatabaseTasks {
    protected $pdoDriver = 'pgsql';
    public function __construct() {
        $this->tasks[] = array(
            'function' => 'checkEncoding',
            'arguments' => array(),
        );
        $this->tasks[] = array(
            'function' => 'checkPHPVersion',
            'arguments' => array(),
        );
        $this->tasks[] = array(
            'function' => 'checkBinaryOutput',
            'arguments' => array(),
        );
        $this->tasks[] = array(
            'function' => 'initializeDatabase',
            'arguments' => array(),
        );
    }
    public function name() {
        return st('PostgreSQL');
    }
    public function minimumVersion() {
        return '8.3';
    }
    
    /**
     * Check encoding is UTF8.
     */
    protected function checkEncoding() {
        try {
            if (db_query('SHOW server_encoding')->fetchField() == 'UTF8') {
                $this->pass(st('Database is encoded in UTF-8'));
            }
            else {
                $replacements = array(
                    '%encoding' => 'UTF8',
                    '%driver' => $this->name(),
                    '!link' => '<a href="INSTALL.pgsql.txt">INSTALL.pgsql.txt</a>',
                );
                $text = 'The %driver database must use %encoding encoding to work with Drupal.';
                $text .= 'Recreate the database with %encoding encoding. See !link for more details.';
                $this->fail(st($text, $replacements));
            }
        } catch (Exception $e) {
            $this->fail(st('Drupal could not determine the encoding of the database was set to UTF-8'));
        }
    }
    
    /**
     * Check PHP version.
     *
     * There are two bugs in PDO_pgsql affecting Drupal:
     *
     * - in versions < 5.2.7, PDO_pgsql refuses to insert an empty string into
     *   a NOT NULL BLOB column. See: http://bugs.php.net/bug.php?id=46249
     * - in versions < 5.2.11 and < 5.3.1 that prevents inserting integer values
     *   into numeric columns that exceed the PHP_INT_MAX value.
     *   See: http://bugs.php.net/bug.php?id=48924
     */
    function checkPHPVersion() {
        if (!version_compare(PHP_VERSION, '5.2.11', '>=') || version_compare(PHP_VERSION, '5.3.0', '>=') && !version_compare(PHP_VERSION, '5.3.1', '>=')) {
            $this->fail(st('The version of PHP you are using has known issues with PostgreSQL. You need to upgrade PHP to 5.2.11, 5.3.1 or greater.'));
        }
    }
    
    /**
     * Check Binary Output.
     *
     * Unserializing does not work on Postgresql 9 when bytea_output is 'hex'.
     */
    function checkBinaryOutput() {
        // PostgreSQL < 9 doesn't support bytea_output, so verify we are running
        // at least PostgreSQL 9.
        $database_connection = Database::getConnection();
        if (version_compare($database_connection->version(), '9') >= 0) {
            if (!$this->checkBinaryOutputSuccess()) {
                // First try to alter the database. If it fails, raise an error telling
                // the user to do it themselves.
                $connection_options = $database_connection->getConnectionOptions();
                // It is safe to include the database name directly here, because this
                // code is only called when a connection to the database is already
                // established, thus the database name is guaranteed to be a correct
                // value.
                $query = "ALTER DATABASE \"" . $connection_options['database'] . "\" SET bytea_output = 'escape';";
                try {
                    db_query($query);
                } catch (Exception $e) {
                    // Ignore possible errors when the user doesn't have the necessary
                    // privileges to ALTER the database.
                }
                // Close the database connection so that the configuration parameter
                // is applied to the current connection.
                db_close();
                // Recheck, if it fails, finally just rely on the end user to do the
                // right thing.
                if (!$this->checkBinaryOutputSuccess()) {
                    $replacements = array(
                        '%setting' => 'bytea_output',
                        '%current_value' => 'hex',
                        '%needed_value' => 'escape',
                        '!query' => "<code>" . $query . "</code>",
                    );
                    $this->fail(st("The %setting setting is currently set to '%current_value', but needs to be '%needed_value'. Change this by running the following query: !query", $replacements));
                }
            }
        }
    }
    
    /**
     * Verify that a binary data roundtrip returns the original string.
     */
    protected function checkBinaryOutputSuccess() {
        $bytea_output = db_query("SELECT 'encoding'::bytea AS output")->fetchField();
        return $bytea_output == 'encoding';
    }
    
    /**
     * Make PostgreSQL Drupal friendly.
     */
    function initializeDatabase() {
        // We create some functions using global names instead of prefixing them
        // like we do with table names. This is so that we don't double up if more
        // than one instance of Drupal is running on a single database. We therefore
        // avoid trying to create them again in that case.
        try {
            // Create functions.
            db_query('CREATE OR REPLACE FUNCTION "greatest"(numeric, numeric) RETURNS numeric AS
        \'SELECT CASE WHEN (($1 > $2) OR ($2 IS NULL)) THEN $1 ELSE $2 END;\'
        LANGUAGE \'sql\'');
            db_query('CREATE OR REPLACE FUNCTION "greatest"(numeric, numeric, numeric) RETURNS numeric AS
        \'SELECT greatest($1, greatest($2, $3));\'
        LANGUAGE \'sql\'');
            // Don't use {} around pg_proc table.
            if (!db_query("SELECT COUNT(*) FROM pg_proc WHERE proname = 'rand'")->fetchField()) {
                db_query('CREATE OR REPLACE FUNCTION "rand"() RETURNS float AS
          \'SELECT random();\'
          LANGUAGE \'sql\'');
            }
            db_query('CREATE OR REPLACE FUNCTION "substring_index"(text, text, integer) RETURNS text AS
        \'SELECT array_to_string((string_to_array($1, $2)) [1:$3], $2);\'
        LANGUAGE \'sql\'');
            // Using || to concatenate in Drupal is not recommended because there are
            // database drivers for Drupal that do not support the syntax, however
            // they do support CONCAT(item1, item2) which we can replicate in
            // PostgreSQL. PostgreSQL requires the function to be defined for each
            // different argument variation the function can handle.
            db_query('CREATE OR REPLACE FUNCTION "concat"(anynonarray, anynonarray) RETURNS text AS
        \'SELECT CAST($1 AS text) || CAST($2 AS text);\'
        LANGUAGE \'sql\'
      ');
            db_query('CREATE OR REPLACE FUNCTION "concat"(text, anynonarray) RETURNS text AS
        \'SELECT $1 || CAST($2 AS text);\'
        LANGUAGE \'sql\'
      ');
            db_query('CREATE OR REPLACE FUNCTION "concat"(anynonarray, text) RETURNS text AS
        \'SELECT CAST($1 AS text) || $2;\'
        LANGUAGE \'sql\'
      ');
            db_query('CREATE OR REPLACE FUNCTION "concat"(text, text) RETURNS text AS
        \'SELECT $1 || $2;\'
        LANGUAGE \'sql\'
      ');
            $this->pass(st('PostgreSQL has initialized itself.'));
        } catch (Exception $e) {
            $this->fail(st('Drupal could not be correctly setup with the existing database. Revise any errors.'));
        }
    }

}