<?php

/**

 * Zend Framework

 *

 * LICENSE

 *

 * This source file is subject to the new BSD license that is bundled

 * with this package in the file LICENSE.txt.

 * It is also available through the world-wide-web at this URL:

 * http://framework.zend.com/license/new-bsd

 * If you did not receive a copy of the license and are unable to

 * obtain it through the world-wide-web, please send an email

 * to license@zend.com so we can send you a copy immediately.

 *

 * @category   Zend

 * @package    Zend_Db

 * @subpackage Adapter

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 * @version    $Id: Sqlite.php 20096 2010-01-06 02:05:09Z bkarwin $

 */

/**

 * @see Zend_Db_Adapter_Pdo_Abstract

 */

require_once 'Zend/Db/Adapter/Pdo/Abstract.php';

/**

 * Class for connecting to SQLite2 and SQLite3 databases and performing common operations.

 *

 * @category   Zend

 * @package    Zend_Db

 * @subpackage Adapter

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

 * @license    http://framework.zend.com/license/new-bsd     New BSD License

 */

class Zend_Db_Adapter_Pdo_Sqlite extends Zend_Db_Adapter_Pdo_Abstract

{

    /**

     * PDO type

     *

     * @var string

     */

     protected $_pdoType = 'sqlite';

    /**

     * Keys are UPPERCASE SQL datatypes or the constants

     * Zend_Db::INT_TYPE, Zend_Db::BIGINT_TYPE, or Zend_Db::FLOAT_TYPE.

     *

     * Values are:

     * 0 = 32-bit integer

     * 1 = 64-bit integer

     * 2 = float or decimal

     *

     * @var array Associative array of datatypes to values 0, 1, or 2.

     */

    protected $_numericDataTypes = array(

        Zend_Db::INT_TYPE    => Zend_Db::INT_TYPE,

        Zend_Db::BIGINT_TYPE => Zend_Db::BIGINT_TYPE,

        Zend_Db::FLOAT_TYPE  => Zend_Db::FLOAT_TYPE,

        'INTEGER'            => Zend_Db::BIGINT_TYPE,

        'REAL'               => Zend_Db::FLOAT_TYPE

    );

    /**

     * Constructor.

     *

     * $config is an array of key/value pairs containing configuration

     * options.  Note that the SQLite options are different than most of

     * the other PDO adapters in that no username or password are needed.

     * Also, an extra config key "sqlite2" specifies compatibility mode.

     *

     * dbname    => (string) The name of the database to user (required,

     *                       use :memory: for memory-based database)

     *

     * sqlite2   => (boolean) PDO_SQLITE defaults to SQLite 3.  For compatibility

     *                        with an older SQLite 2 database, set this to TRUE.

     *

     * @param array $config An array of configuration keys.

     */

    public function __construct(array $config = array())

    {

        if (isset($config['sqlite2']) && $config['sqlite2']) {

            $this->_pdoType = 'sqlite2';

        }

        // SQLite uses no username/password.  Stub to satisfy parent::_connect()

        $this->_config['username'] = null;

        $this->_config['password'] = null;

        return parent::__construct($config);

    }

    /**

     * Check for config options that are mandatory.

     * Throw exceptions if any are missing.

     *

     * @param array $config

     * @throws Zend_Db_Adapter_Exception

     */

    protected function _checkRequiredOptions(array $config)

    {

        // we need at least a dbname

        if (! array_key_exists('dbname', $config)) {

            /** @see Zend_Db_Adapter_Exception */

            require_once 'Zend/Db/Adapter/Exception.php';

            throw new Zend_Db_Adapter_Exception("Configuration array must have a key for 'dbname' that names the database instance");

        }

    }

    /**

     * DSN builder

     */

    protected function _dsn()

    {

        return $this->_pdoType .':'. $this->_config['dbname'];

    }

    /**

     * Special configuration for SQLite behavior: make sure that result sets

     * contain keys like 'column' instead of 'table.column'.

     *

     * @throws Zend_Db_Adapter_Exception

     */

    protected function _connect()

    {

        /**

         * if we already have a PDO object, no need to re-connect.

         */

        if ($this->_connection) {

            return;

        }

        parent::_connect();

        $retval = $this->_connection->exec('PRAGMA full_column_names=0');

        if ($retval === false) {

            $error = $this->_connection->errorInfo();

            /** @see Zend_Db_Adapter_Exception */

            require_once 'Zend/Db/Adapter/Exception.php';

            throw new Zend_Db_Adapter_Exception($error[2]);

        }

        $retval = $this->_connection->exec('PRAGMA short_column_names=1');

        if ($retval === false) {

            $error = $this->_connection->errorInfo();

            /** @see Zend_Db_Adapter_Exception */

            require_once 'Zend/Db/Adapter/Exception.php';

            throw new Zend_Db_Adapter_Exception($error[2]);

        }

    }

    /**

     * Returns a list of the tables in the database.

     *

     * @return array

     */

    public function listTables()

    {

        $sql = "SELECT name FROM sqlite_master WHERE type='table' "

             . "UNION ALL SELECT name FROM sqlite_temp_master "

             . "WHERE type='table' ORDER BY name";

        return $this->fetchCol($sql);

    }

    /**

     * Returns the column descriptions for a table.

     *

     * The return value is an associative array keyed by the column name,

     * as returned by the RDBMS.

     *

     * The value of each array element is an associative array

     * with the following keys:

     *

     * SCHEMA_NAME      => string; name of database or schema

     * TABLE_NAME       => string;

     * COLUMN_NAME      => string; column name

     * COLUMN_POSITION  => number; ordinal position of column in table

     * DATA_TYPE        => string; SQL datatype name of column

     * DEFAULT          => string; default expression of column, null if none

     * NULLABLE         => boolean; true if column can have nulls

     * LENGTH           => number; length of CHAR/VARCHAR

     * SCALE            => number; scale of NUMERIC/DECIMAL

     * PRECISION        => number; precision of NUMERIC/DECIMAL

     * UNSIGNED         => boolean; unsigned property of an integer type

     * PRIMARY          => boolean; true if column is part of the primary key

     * PRIMARY_POSITION => integer; position of column in primary key

     * IDENTITY         => integer; true if column is auto-generated with unique values

     *

     * @param string $tableName

     * @param string $schemaName OPTIONAL

     * @return array

     */

    public function describeTable($tableName, $schemaName = null)

    {

        $sql = 'PRAGMA ';

        if ($schemaName) {

            $sql .= $this->quoteIdentifier($schemaName) . '.';

        }

        $sql .= 'table_info('.$this->quoteIdentifier($tableName).')';

        $stmt = $this->query($sql);

        /**

         * Use FETCH_NUM so we are not dependent on the CASE attribute of the PDO connection

         */

        $result = $stmt->fetchAll(Zend_Db::FETCH_NUM);

        $cid        = 0;

        $name       = 1;

        $type       = 2;

        $notnull    = 3;

        $dflt_value = 4;

        $pk         = 5;

        $desc = array();

        $p = 1;

        foreach ($result as $key => $row) {

            list($length, $scale, $precision, $primary, $primaryPosition, $identity) =

                array(null, null, null, false, null, false);

            if (preg_match('/^((?:var)?char)\((\d+)\)/i', $row[$type], $matches)) {

                $row[$type] = $matches[1];

                $length = $matches[2];

            } else if (preg_match('/^decimal\((\d+),(\d+)\)/i', $row[$type], $matches)) {

                $row[$type] = 'DECIMAL';

                $precision = $matches[1];

                $scale = $matches[2];

            }

            if ((bool) $row[$pk]) {

                $primary = true;

                $primaryPosition = $p;

                /**

                 * SQLite INTEGER primary key is always auto-increment.

                 */

                $identity = (bool) ($row[$type] == 'INTEGER');

                ++$p;

            }

            $desc[$this->foldCase($row[$name])] = array(

                'SCHEMA_NAME'      => $this->foldCase($schemaName),

                'TABLE_NAME'       => $this->foldCase($tableName),

                'COLUMN_NAME'      => $this->foldCase($row[$name]),

                'COLUMN_POSITION'  => $row[$cid]+1,

                'DATA_TYPE'        => $row[$type],

                'DEFAULT'          => $row[$dflt_value],

                'NULLABLE'         => ! (bool) $row[$notnull],

                'LENGTH'           => $length,

                'SCALE'            => $scale,

                'PRECISION'        => $precision,

                'UNSIGNED'         => null, // Sqlite3 does not support unsigned data

                'PRIMARY'          => $primary,

                'PRIMARY_POSITION' => $primaryPosition,

                'IDENTITY'         => $identity

            );

        }

        return $desc;

    }

    /**

     * Adds an adapter-specific LIMIT clause to the SELECT statement.

     *

     * @param string $sql

     * @param integer $count

     * @param integer $offset OPTIONAL

     * @return string

     */

    public function limit($sql, $count, $offset = 0)

    {

        $count = intval($count);

        if ($count <= 0) {

            /** @see Zend_Db_Adapter_Exception */

            require_once 'Zend/Db/Adapter/Exception.php';

            throw new Zend_Db_Adapter_Exception("LIMIT argument count=$count is not valid");

        }

        $offset = intval($offset);

        if ($offset < 0) {

            /** @see Zend_Db_Adapter_Exception */

            require_once 'Zend/Db/Adapter/Exception.php';

            throw new Zend_Db_Adapter_Exception("LIMIT argument offset=$offset is not valid");

        }

        $sql .= " LIMIT $count";

        if ($offset > 0) {

            $sql .= " OFFSET $offset";

        }

        return $sql;

    }

}