<?php

/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2019 - 2022, CodeIgniter Foundation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @package CodeIgniter
 * @author  EllisLab Dev Team
 * @copyright   Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
 * @copyright   Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/)
 * @copyright   Copyright (c) 2019 - 2022, CodeIgniter Foundation (https://codeigniter.com/)
 * @license https://opensource.org/licenses/MIT MIT License
 * @link    https://codeigniter.com
 * @since   Version 3.0.0
 * @filesource
 */

defined('BASEPATH') or exit('No direct script access allowed');

/**
 * Firebird/Interbase Database Adapter Class
 *
 * Note: _DB is an extender class that the app controller
 * creates dynamically based on whether the query builder
 * class is being used or not.
 *
 * @package     CodeIgniter
 * @subpackage  Drivers
 * @category    Database
 * @author      EllisLab Dev Team
 * @link        https://codeigniter.com/userguide3/database/
 */
class CI_DB_ibase_driver extends CI_DB
{
    /**
     * Database driver
     *
     * @var string
     */
    public $dbdriver = 'ibase';

    // --------------------------------------------------------------------

    /**
     * ORDER BY random keyword
     *
     * @var array
     */
    protected $_random_keyword = array('RAND()', 'RAND()');

    /**
     * IBase Transaction status flag
     *
     * @var resource
     */
    protected $_ibase_trans;

    // --------------------------------------------------------------------

    /**
     * Non-persistent database connection
     *
     * @param   bool    $persistent
     * @return  resource
     */
    public function db_connect($persistent = false)
    {
        return ($persistent === true)
            ? ibase_pconnect($this->hostname . ':' . $this->database, $this->username, $this->password, $this->char_set)
            : ibase_connect($this->hostname . ':' . $this->database, $this->username, $this->password, $this->char_set);
    }

    // --------------------------------------------------------------------

    /**
     * Database version number
     *
     * @return  string
     */
    public function version()
    {
        if (isset($this->data_cache['version'])) {
            return $this->data_cache['version'];
        }

        if (($service = ibase_service_attach($this->hostname, $this->username, $this->password))) {
            $this->data_cache['version'] = ibase_server_info($service, IBASE_SVC_SERVER_VERSION);

            // Don't keep the service open
            ibase_service_detach($service);
            return $this->data_cache['version'];
        }

        return false;
    }

    // --------------------------------------------------------------------

    /**
     * Execute the query
     *
     * @param   string  $sql    an SQL query
     * @return  resource
     */
    protected function _execute($sql)
    {
        return ibase_query(isset($this->_ibase_trans) ? $this->_ibase_trans : $this->conn_id, $sql);
    }

    // --------------------------------------------------------------------

    /**
     * Begin Transaction
     *
     * @return  bool
     */
    protected function _trans_begin()
    {
        if (($trans_handle = ibase_trans($this->conn_id)) === false) {
            return false;
        }

        $this->_ibase_trans = $trans_handle;
        return true;
    }

    // --------------------------------------------------------------------

    /**
     * Commit Transaction
     *
     * @return  bool
     */
    protected function _trans_commit()
    {
        if (ibase_commit($this->_ibase_trans)) {
            $this->_ibase_trans = null;
            return true;
        }

        return false;
    }

    // --------------------------------------------------------------------

    /**
     * Rollback Transaction
     *
     * @return  bool
     */
    protected function _trans_rollback()
    {
        if (ibase_rollback($this->_ibase_trans)) {
            $this->_ibase_trans = null;
            return true;
        }

        return false;
    }

    // --------------------------------------------------------------------

    /**
     * Affected Rows
     *
     * @return  int
     */
    public function affected_rows()
    {
        return ibase_affected_rows($this->conn_id);
    }

    // --------------------------------------------------------------------

    /**
     * Insert ID
     *
     * @param   string  $generator_name
     * @param   int $inc_by
     * @return  int
     */
    public function insert_id($generator_name, $inc_by = 0)
    {
        //If a generator hasn't been used before it will return 0
        return ibase_gen_id('"' . $generator_name . '"', $inc_by);
    }

    // --------------------------------------------------------------------

    /**
     * List table query
     *
     * Generates a platform-specific query string so that the table names can be fetched
     *
     * @param   bool    $prefix_limit
     * @return  string
     */
    protected function _list_tables($prefix_limit = false)
    {
        $sql = 'SELECT TRIM("RDB$RELATION_NAME") AS TABLE_NAME FROM "RDB$RELATIONS" WHERE "RDB$RELATION_NAME" NOT LIKE \'RDB$%\' AND "RDB$RELATION_NAME" NOT LIKE \'MON$%\'';

        if ($prefix_limit !== false && $this->dbprefix !== '') {
            return $sql . ' AND TRIM("RDB$RELATION_NAME") AS TABLE_NAME LIKE \'' . $this->escape_like_str($this->dbprefix) . "%' "
                . sprintf($this->_like_escape_str, $this->_like_escape_chr);
        }

        return $sql;
    }

    // --------------------------------------------------------------------

    /**
     * Show column query
     *
     * Generates a platform-specific query string so that the column names can be fetched
     *
     * @param   string  $table
     * @return  string
     */
    protected function _list_columns($table = '')
    {
        return 'SELECT TRIM("RDB$FIELD_NAME") AS COLUMN_NAME FROM "RDB$RELATION_FIELDS" WHERE "RDB$RELATION_NAME" = ' . $this->escape($table);
    }

    // --------------------------------------------------------------------

    /**
     * Returns an object with field data
     *
     * @param   string  $table
     * @return  array
     */
    public function field_data($table)
    {
        $sql = 'SELECT "rfields"."RDB$FIELD_NAME" AS "name",
				CASE "fields"."RDB$FIELD_TYPE"
					WHEN 7 THEN \'SMALLINT\'
					WHEN 8 THEN \'INTEGER\'
					WHEN 9 THEN \'QUAD\'
					WHEN 10 THEN \'FLOAT\'
					WHEN 11 THEN \'DFLOAT\'
					WHEN 12 THEN \'DATE\'
					WHEN 13 THEN \'TIME\'
					WHEN 14 THEN \'CHAR\'
					WHEN 16 THEN \'INT64\'
					WHEN 27 THEN \'DOUBLE\'
					WHEN 35 THEN \'TIMESTAMP\'
					WHEN 37 THEN \'VARCHAR\'
					WHEN 40 THEN \'CSTRING\'
					WHEN 261 THEN \'BLOB\'
					ELSE NULL
				END AS "type",
				"fields"."RDB$FIELD_LENGTH" AS "max_length",
				"rfields"."RDB$DEFAULT_VALUE" AS "default"
			FROM "RDB$RELATION_FIELDS" "rfields"
				JOIN "RDB$FIELDS" "fields" ON "rfields"."RDB$FIELD_SOURCE" = "fields"."RDB$FIELD_NAME"
			WHERE "rfields"."RDB$RELATION_NAME" = ' . $this->escape($table) . '
			ORDER BY "rfields"."RDB$FIELD_POSITION"';

        return (($query = $this->query($sql)) !== false)
            ? $query->result_object()
            : false;
    }

    // --------------------------------------------------------------------

    /**
     * Error
     *
     * Returns an array containing code and message of the last
     * database error that has occurred.
     *
     * @return  array
     */
    public function error()
    {
        return array('code' => ibase_errcode(), 'message' => ibase_errmsg());
    }

    // --------------------------------------------------------------------

    /**
     * Update statement
     *
     * Generates a platform-specific update string from the supplied data
     *
     * @param   string  $table
     * @param   array   $values
     * @return  string
     */
    protected function _update($table, $values)
    {
        $this->qb_limit = false;
        return parent::_update($table, $values);
    }

    // --------------------------------------------------------------------

    /**
     * Truncate statement
     *
     * Generates a platform-specific truncate string from the supplied data
     *
     * If the database does not support the TRUNCATE statement,
     * then this method maps to 'DELETE FROM table'
     *
     * @param   string  $table
     * @return  string
     */
    protected function _truncate($table)
    {
        return 'DELETE FROM ' . $table;
    }

    // --------------------------------------------------------------------

    /**
     * Delete statement
     *
     * Generates a platform-specific delete string from the supplied data
     *
     * @param   string  $table
     * @return  string
     */
    protected function _delete($table)
    {
        $this->qb_limit = false;
        return parent::_delete($table);
    }

    // --------------------------------------------------------------------

    /**
     * LIMIT
     *
     * Generates a platform-specific LIMIT clause
     *
     * @param   string  $sql    SQL Query
     * @return  string
     */
    protected function _limit($sql)
    {
        // Limit clause depends on if Interbase or Firebird
        if (stripos($this->version(), 'firebird') !== false) {
            $select = 'FIRST ' . $this->qb_limit
                . ($this->qb_offset ? ' SKIP ' . $this->qb_offset : '');
        } else {
            $select = 'ROWS '
                . ($this->qb_offset ? $this->qb_offset . ' TO ' . ($this->qb_limit + $this->qb_offset) : $this->qb_limit);
        }

        return preg_replace('`SELECT`i', 'SELECT ' . $select, $sql, 1);
    }

    // --------------------------------------------------------------------

    /**
     * Insert batch statement
     *
     * Generates a platform-specific insert string from the supplied data.
     *
     * @param   string  $table  Table name
     * @param   array   $keys   INSERT keys
     * @param   array   $values INSERT values
     * @return  string|bool
     */
    protected function _insert_batch($table, $keys, $values)
    {
        return ($this->db_debug) ? $this->display_error('db_unsupported_feature') : false;
    }

    // --------------------------------------------------------------------

    /**
     * Close DB Connection
     *
     * @return  void
     */
    protected function _close()
    {
        ibase_close($this->conn_id);
    }
}