<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.2.4 or newer
 *
 * NOTICE OF LICENSE
 *
 * Licensed under the Open Software License version 3.0
 *
 * This source file is subject to the Open Software License (OSL 3.0) that is
 * bundled with this package in the files license.txt / license.rst.  It is
 * also available through the world wide web at this URL:
 * http://opensource.org/licenses/OSL-3.0
 * 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
 * licensing@ellislab.com so we can send you a copy immediately.
 *
 * @package		CodeIgniter
 * @author		EllisLab Dev Team
 * @copyright	Copyright (c) 2008 - 2012, EllisLab, Inc. (http://ellislab.com/)
 * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
 * @link		http://codeigniter.com
 * @since		Version 3.0.0
 * @filesource
 */

/**
 * PDO PostgreSQL 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		http://codeigniter.com/user_guide/database/
 */
class CI_DB_pdo_pgsql_driver extends CI_DB_pdo_driver {

	public $subdriver = 'pgsql';

	protected $_random_keyword = ' RANDOM()';

	/**
	 * Constructor
	 *
	 * Builds the DSN if not already set.
	 *
	 * @param	array
	 * @return	void
	 */
	public function __construct($params)
	{
		parent::__construct($params);

		if (empty($this->dsn))
		{
			$this->dsn = 'pgsql:host='.(empty($this->hostname) ? 'localhost' : $this->hostname);

			empty($this->port) OR $this->dsn .= ';port='.$this->port;
			empty($this->database) OR $this->dsn .= ';dbname='.$this->database;
		}
	}

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

	/**
	 * Insert ID
	 *
	 * @param	string
	 * @return	int
	 */
	public function insert_id($name = NULL)
	{
		if ($name === NULL && version_compare($this->version(), '8.1', '>='))
		{
			$query = $this->query('SELECT LASTVAL() AS ins_id');
			$query = $query->row();
			return $query->ins_id;
		}

		return $this->conn_id->lastInsertId($name);
	}

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

	/**
	 * Show table query
	 *
	 * Generates a platform-specific query string so that the table names can be fetched
	 *
	 * @param	bool
	 * @return	string
	 */
	protected function _list_tables($prefix_limit = FALSE)
	{
		$sql = 'SELECT "table_name" FROM "information_schema"."tables" WHERE "table_schema" = \'public\'';

		if ($prefix_limit === TRUE && $this->dbprefix !== '')
		{
			return $sql.' AND "table_name" LIKE \''
				.$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	the table name
	 * @return	string
	 */
	protected function _list_columns($table = '')
	{
		return 'SELECT "column_name" FROM "information_schema"."columns" WHERE "table_name" = '.$this->escape($table);
	}

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

	/**
	 * Field data query
	 *
	 * Generates a platform-specific query so that the column data can be retrieved
	 *
	 * @param	string	the table name
	 * @return	string
	 */
	protected function _field_data($table)
	{
		return 'SELECT * FROM '.$this->protect_identifiers($table).' LIMIT 1';
	}

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

	/**
	 * From Tables
	 *
	 * This function implicitly groups FROM tables so there is no confusion
	 * about operator precedence in harmony with SQL standards
	 *
	 * @param	array
	 * @return	string
	 */
	protected function _from_tables($tables)
	{
		return is_array($tables) ? implode(', ', $tables) : $tables;
	}

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

	/**
	 * Update statement
	 *
	 * Generates a platform-specific update string from the supplied data
	 *
	 * @param	string	the table name
	 * @param	array	the update data
	 * @param	array	the where clause
	 * @param	array	the orderby clause (ignored)
	 * @param	array	the limit clause (ignored)
	 * @param	array	the like clause
	 * @return	string
         */
	protected function _update($table, $values, $where, $orderby = array(), $limit = FALSE, $like = array())
	{
		foreach ($values as $key => $val)
		{
			$valstr[] = $key.' = '.$val;
		}

		$where = empty($where) ? '' : ' WHERE '.implode(' ', $where);

		if ( ! empty($like))
		{
			$where .= ($where === '' ? ' WHERE ' : ' AND ').implode(' ', $like);
		}

		return 'UPDATE '.$table.' SET '.implode(', ', $valstr).$where;
	}

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

	/**
	 * Update_Batch statement
	 *
	 * Generates a platform-specific batch update string from the supplied data
	 *
	 * @param	string	the table name
	 * @param	array	the update data
	 * @param	array	the where clause
	 * @return	string
	 */
	protected function _update_batch($table, $values, $index, $where = NULL)
	{
		$ids = array();
		foreach ($values as $key => $val)
		{
			$ids[] = $val[$index];

			foreach (array_keys($val) as $field)
			{
				if ($field !== $index)
				{
					$final[$field][] =  'WHEN '.$val[$index].' THEN '.$val[$field];
				}
			}
		}

		$cases = '';
		foreach ($final as $k => $v)
		{
			$cases .= $k.' = (CASE '.$k."\n"
				.implode("\n", $v)."\n"
				.'ELSE '.$k.' END), ';
		}

		return 'UPDATE '.$table.' SET '.substr($cases, 0, -2)
			.' WHERE '.(($where !== '' && count($where) > 0) ? implode(' ', $where).' AND ' : '')
			.$index.' IN('.implode(',', $ids).')';
	}

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

	/**
	 * Delete statement
	 *
	 * Generates a platform-specific delete string from the supplied data
	 *
	 * @param	string	the table name
	 * @param	array	the where clause
	 * @param	array	the like clause
	 * @param	string	the limit clause (ignored)
	 * @return	string
	 */
	protected function _delete($table, $where = array(), $like = array(), $limit = FALSE)
	{
		$conditions = array();

		empty($where) OR $conditions[] = implode(' ', $where);
		empty($like) OR $conditions[] = implode(' ', $like);

		return 'DELETE FROM '.$table.(count($conditions) > 0 ? ' WHERE '.implode(' AND ', $conditions) : '');
	}

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

	/**
	 * Limit string
	 *
	 * Generates a platform-specific LIMIT clause
	 *
	 * @param	string	the sql query string
	 * @param	int	the number of rows to limit the query to
	 * @param	int	the offset value
	 * @return	string
	 */
	protected function _limit($sql, $limit, $offset)
	{
		return $sql.' LIMIT '.$limit.($offset ? '' : ' OFFSET '.$offset);
	}

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

	/**
	 * Where
	 *
	 * Called by where() or or_where()
	 *
	 * @param	mixed
	 * @param	mixed
	 * @param	string
	 * @return	object
	 */
	protected function _where($key, $value = NULL, $type = 'AND ', $escape = NULL)
	{
		if ( ! is_array($key))
		{
			$key = array($key => $value);
		}

		// If the escape value was not set will will base it on the global setting
		is_bool($escape) OR $escape = $this->_protect_identifiers;

		foreach ($key as $k => $v)
		{
			$prefix = (count($this->qb_where) === 0 && count($this->qb_cache_where) === 0)
				? $this->_group_get_type('')
				: $this->_group_get_type($type);

			$k = (($op = $this->_get_operator($k)) !== FALSE)
				? $this->protect_identifiers(substr($k, 0, strpos($k, $op)), FALSE, $escape).strstr($k, $op)
				: $this->protect_identifiers($k, FALSE, $escape);

			if (is_null($v) && ! $this->_has_operator($k))
			{
				// value appears not to have been set, assign the test to IS NULL
				$k .= ' IS NULL';
			}

			if ( ! is_null($v))
			{
				if ($escape === TRUE)
				{
					$v = ' '.$this->escape($v);
				}
				elseif (is_bool($v))
				{
					$v = ($v ? ' TRUE' : ' FALSE');
				}

				if ( ! $this->_has_operator($k))
				{
					$k .= ' = ';
				}
			}

			$this->qb_where[] = $prefix.$k.$v;
			if ($this->qb_caching === TRUE)
			{
				$this->qb_cache_where[] = $prefix.$k.$v;
				$this->qb_cache_exists[] = 'where';
			}

		}

		return $this;
	}

}

/* End of file pdo_pgsql_driver.php */
/* Location: ./system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php */