<?php

	/**
	 * PHP-Oracle Claw DB adapter
	 *
	 * @package claw.ext
	 * @author Tomas Varaneckas <tomas [dot] varaneckas [at] gmail [dot] com>
	 * @version $Id: OracleClawDB.php 145 2006-04-06 18:23:19Z metasite $
	 */
	class OracleClawDB implements ClawDB
	{
		/**
		 * Current result set..
		 *
		 * @var Oracle Statement
		 */
		protected $stmt = null;

		/**
		 * Last primary key
		 *
		 * @var int
		 */
		protected $last_pk = null;

		/**
		 * Oracle Connection
		 *
		 * @var Oracle connection resource
		 */
		protected $conn = null;

		/**
		 * Connects to database
		 *
		 * @param Array $cfg array('host', 'user', 'pass', 'db')
		 * @throws DBClawException when connection fails
		 */
		public function connect($cfg)
		{
			if (!function_exists('oci_pconnect'))
			{
				throw new DBClawException('Oracle php extension not loaded');
			}
			if (!$this->conn = @oci_pconnect($cfg['user'], $cfg['pass'], $cfg['db'], $cfg['charset']))
			{
				$err = oci_error();
				throw new DBClawException(
					'Cannot connect to Oracle (' . $cfg['user'] . ', '
					. $err['message'] . ')');
			}
		}

		/**
		 * Disconnector
		 */
		public function disconnect()
		{
			@oci_close($this->conn);
			$this->conn = null;
		}

		/**
		 * Gets an associative array of fields => values
		 * by table, primary key value, and primary key field
		 *
		 * @param string $table Table to get data from
		 * @param string $pk_value Primary Key value
		 * @param string $pk_field Primary Key field (default = 'id')
		 * @return Array
		 */
		public function getByPK($table, $pk_value, $pk_field = 'id')
		{
			return $this->getRow('select * from ' . $table . ' where '
				. $pk_field . ' = :id', array('id' => $pk_value));
		}

		/**
		 * Define table and provide array of data to be inserted, this function
		 * does the operation
		 *
		 * @param string $table Table we are inserting data into
		 * @param Array $data Associative array of data to be inserted
		 */
		public function insert($table, $data = array())
		{
			$fields = implode(', ', array_keys($data));
			$bindings = array();
			foreach ($data as $key => &$value)
			{
				$bindings[] = ':' . $key;
			}
			$data['last_pk'] =& $this->last_pk;
			$this->query('insert into ' . $table . ' (' . $fields
				. ') values (' . implode(', ', $bindings) . ') '
				. 'returning ' . $pk_field . ' into :last_pk', $data);
		}

		public function delete($table, $pk_value, $pk_field = 'id')
		{
			if ($pk_value)
			{
				$this->query('delete from ' . $table . ' where '
					. $pk_field . ' = :id', array('id' => $pk_value));
			}
		}

		/**
		 * Update method, which is meant to modify ONE record BY primary key
		 *
		 * @param string $table Table we are updating
		 * @param Array $data Associative array of data to be updated
		 * @param mixed $pk_value Value of primary key of record we're updating
		 * @param string $pk_field Primary Key field (default - 'id'
		 */
		public function update($table, $data = array(), $pk_value, $pk_field = 'id')
		{
			$sql = array();
			foreach ($data as $field => &$value)
			{
				$sql[] = $field . ' = :' . $field;
			}
			$this->query('update ' . $table . ' set ' . implode(', ', $sql)
				. ' where ' . $pk_field . ' = :id', array('id' => $pk_value));
		}

		/**
		 * Gets array of arrays of rows with data from SQL query.
		 * Mind the portability!
		 *
		 * @param string $sql SQL query
		 * @param Array $params Array of query parameters. Can hold fetchmode
		 *		or variables that need to be bound..
		 * @return Array
		 */
		public function &getArray($sql, $params = array())
		{
			$result = array();
			$this->query($sql, $params);
			while ($r = $this->fetch())
			{
				$result[] = $r;
			}
			$this->free();
			return $result;
		}

		/**
		 * Gets array of row data from SQL query
		 * Mind the portability!
		 *
		 * @param string $sql SQL query
		 * @param Array $params Array of query parameters. Can hold fetchmode
		 *		or variables that need to be bound
		 */
		public function &getRow($sql, $params = array())
		{
			$this->query($sql, $params);
			$result = $this->fetch();
			$this->free();
			return $result;
		}

		/**
		 * Gets single cell (usually string, not array!) from SQL query
		 * Mind the portability!
		 *
		 * @param string $sql SQL query
		 * @param Array $params Array of query parameters. Can hold fetchmode
		 *		or variables that need to be bound
		 */
		public function &getCell($sql, $params = array())
		{
			$this->query($sql, $params);
			$result = $this->fetch();
			if (is_array($result))
			{
				$result = array_pop($result);
			}
			$this->free();
			return $result;
		}

		/**
		 * Gets result set (whatever the kind..) from SQL query
		 * Should assign the result to ClawDB::$result
		 * Mind the portability!
		 *
		 * @param string $sql SQL query
		 * @param Array $params Array of query parameters. Can hold fetchmode
		 *		or variables that need to be bound
		 */
		public function query($sql, $params = array())
		{
			$this->stmt = @oci_parse($this->conn, $sql);

			if (!is_array($params))
			{
				$params = array();
			}
			foreach ($params as $k => &$v)
			{
				@oci_bind_by_name($this->stmt, $k, $v);
			}

			$ok = @oci_execute($this->stmt, OCI_COMMIT_ON_SUCCESS);

			if (!$ok)
			{
				$err = oci_error($this->stmt);
				throw new DBClawException('Invalid SQL Query: ' . $sql . ' ('
					. $err['message'] . ')');
			}
			return oci_num_rows($this->stmt);
		}

		/**
		 * Fetches next result from result set that derrived from ClawDB::query
		 * Result must be at ClawDB::$result
		 *
		 * @param Array $params Array of parameters.. Can hold fetchmode
		 */
		public function fetch($params = array('mode' => OCI_ASSOC))
		{
			return @oci_fetch_array($this->stmt, $params['mode']);
		}

		/**
		 * Releases the ClawDB::$result
		 */
		public function free()
		{
			@oci_free_statement($this->stmt);
		}

		/**
		 * Escaper. As it's oracle, no need for escaping...
		 *
		 * @param string $value not so clean value
		 * @return string clean value
		 */
		public function escape($value)
		{
			return $value;
		}

		/**
		 * Returns last insert id
		 *
		 * @return mixed
		 */
		public function getLastInsertPK()
		{
			return $this->last_pk;
		}
	}
?>