<?php
/*
 *  $Id$
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.doctrine-project.org>.
*/

namespace Doctrine\DBAL\Driver\IbmDb2;

class Db2Statement implements \Doctrine\DBAL\Driver\Statement
{
    private $_stmt = null;

    private $_bindParam = array();

    /**
     * DB2_BINARY, DB2_CHAR, DB2_DOUBLE, or DB2_LONG 
     * @var <type>
     */
    static private $_typeMap = array(
        \PDO::PARAM_INT => DB2_LONG,
        \PDO::PARAM_STR => DB2_CHAR,
    );

    public function __construct($stmt)
    {
        $this->_stmt = $stmt;
    }

    /**
     * Binds a value to a corresponding named or positional
     * placeholder in the SQL statement that was used to prepare the statement.
     *
     * @param mixed $param          Parameter identifier. For a prepared statement using named placeholders,
     *                              this will be a parameter name of the form :name. For a prepared statement
     *                              using question mark placeholders, this will be the 1-indexed position of the parameter
     *
     * @param mixed $value          The value to bind to the parameter.
     * @param integer $type         Explicit data type for the parameter using the PDO::PARAM_* constants.
     *
     * @return boolean              Returns TRUE on success or FALSE on failure.
     */
    function bindValue($param, $value, $type = null)
    {
        return $this->bindParam($param, $value, $type);
    }

    /**
     * Binds a PHP variable to a corresponding named or question mark placeholder in the
     * SQL statement that was use to prepare the statement. Unlike PDOStatement->bindValue(),
     * the variable is bound as a reference and will only be evaluated at the time
     * that PDOStatement->execute() is called.
     *
     * Most parameters are input parameters, that is, parameters that are
     * used in a read-only fashion to build up the query. Some drivers support the invocation
     * of stored procedures that return data as output parameters, and some also as input/output
     * parameters that both send in data and are updated to receive it.
     *
     * @param mixed $param          Parameter identifier. For a prepared statement using named placeholders,
     *                              this will be a parameter name of the form :name. For a prepared statement
     *                              using question mark placeholders, this will be the 1-indexed position of the parameter
     *
     * @param mixed $variable       Name of the PHP variable to bind to the SQL statement parameter.
     *
     * @param integer $type         Explicit data type for the parameter using the PDO::PARAM_* constants. To return
     *                              an INOUT parameter from a stored procedure, use the bitwise OR operator to set the
     *                              PDO::PARAM_INPUT_OUTPUT bits for the data_type parameter.
     * @return boolean              Returns TRUE on success or FALSE on failure.
     */
    function bindParam($column, &$variable, $type = null)
    {
        $this->_bindParam[$column] =& $variable;

        if ($type && isset(self::$_typeMap[$type])) {
            $type = self::$_typeMap[$type];
        } else {
            $type = DB2_CHAR;
        }

        if (!db2_bind_param($this->_stmt, $column, "variable", DB2_PARAM_IN, $type)) {
            throw new Db2Exception(db2_stmt_errormsg());
        }
        return true;
    }

    /**
     * Closes the cursor, enabling the statement to be executed again.
     *
     * @return boolean              Returns TRUE on success or FALSE on failure.
     */
    function closeCursor()
    {
        if (!$this->_stmt) {
            return false;
        }

        $this->_bindParam = array();
        db2_free_result($this->_stmt);
        $ret = db2_free_stmt($this->_stmt);
        $this->_stmt = false;
        return $ret;
    }

    /**
     * columnCount
     * Returns the number of columns in the result set
     *
     * @return integer              Returns the number of columns in the result set represented
     *                              by the PDOStatement object. If there is no result set,
     *                              this method should return 0.
     */
    function columnCount()
    {
        if (!$this->_stmt) {
            return false;
        }
        return db2_num_fields($this->_stmt);
    }

    /**
     * errorCode
     * Fetch the SQLSTATE associated with the last operation on the statement handle
     *
     * @see Doctrine_Adapter_Interface::errorCode()
     * @return string       error code string
     */
    function errorCode()
    {
        return db2_stmt_error();
    }

    /**
     * errorInfo
     * Fetch extended error information associated with the last operation on the statement handle
     *
     * @see Doctrine_Adapter_Interface::errorInfo()
     * @return array        error info array
     */
    function errorInfo()
    {
        return array(
            0 => db2_stmt_errormsg(),
            1 => db2_stmt_error(),
        );
    }

    /**
     * Executes a prepared statement
     *
     * If the prepared statement included parameter markers, you must either:
     * call PDOStatement->bindParam() to bind PHP variables to the parameter markers:
     * bound variables pass their value as input and receive the output value,
     * if any, of their associated parameter markers or pass an array of input-only
     * parameter values
     *
     *
     * @param array $params             An array of values with as many elements as there are
     *                                  bound parameters in the SQL statement being executed.
     * @return boolean                  Returns TRUE on success or FALSE on failure.
     */
    function execute($params = null)
    {
        if (!$this->_stmt) {
            return false;
        }

        /*$retval = true;
        if ($params !== null) {
            $retval = @db2_execute($this->_stmt, $params);
        } else {
            $retval = @db2_execute($this->_stmt);
        }*/
        if ($params === null) {
            ksort($this->_bindParam);
            $params = array_values($this->_bindParam);
        }
        $retval = @db2_execute($this->_stmt, $params);

        if ($retval === false) {
            throw new Db2Exception(db2_stmt_errormsg());
        }
        return $retval;
    }

    /**
     * fetch
     *
     * @see Query::HYDRATE_* constants
     * @param integer $fetchStyle           Controls how the next row will be returned to the caller.
     *                                      This value must be one of the Query::HYDRATE_* constants,
     *                                      defaulting to Query::HYDRATE_BOTH
     *
     * @param integer $cursorOrientation    For a PDOStatement object representing a scrollable cursor,
     *                                      this value determines which row will be returned to the caller.
     *                                      This value must be one of the Query::HYDRATE_ORI_* constants, defaulting to
     *                                      Query::HYDRATE_ORI_NEXT. To request a scrollable cursor for your
     *                                      PDOStatement object,
     *                                      you must set the PDO::ATTR_CURSOR attribute to Doctrine::CURSOR_SCROLL when you
     *                                      prepare the SQL statement with Doctrine_Adapter_Interface->prepare().
     *
     * @param integer $cursorOffset         For a PDOStatement object representing a scrollable cursor for which the
     *                                      $cursorOrientation parameter is set to Query::HYDRATE_ORI_ABS, this value specifies
     *                                      the absolute number of the row in the result set that shall be fetched.
     *
     *                                      For a PDOStatement object representing a scrollable cursor for
     *                                      which the $cursorOrientation parameter is set to Query::HYDRATE_ORI_REL, this value
     *                                      specifies the row to fetch relative to the cursor position before
     *                                      PDOStatement->fetch() was called.
     *
     * @return mixed
     */
    function fetch($fetchStyle = \PDO::FETCH_BOTH)
    {
        switch ($fetchStyle) {
            case \PDO::FETCH_BOTH:
                return db2_fetch_both($this->_stmt);
            case \PDO::FETCH_ASSOC:
                return db2_fetch_assoc($this->_stmt);
            case \PDO::FETCH_NUM:
                return db2_fetch_array($this->_stmt);
            default:
                throw new Db2Exception("Given Fetch-Style " . $fetchStyle . " is not supported.");
        }
    }

    /**
     * Returns an array containing all of the result set rows
     *
     * @param integer $fetchStyle           Controls how the next row will be returned to the caller.
     *                                      This value must be one of the Query::HYDRATE_* constants,
     *                                      defaulting to Query::HYDRATE_BOTH
     *
     * @param integer $columnIndex          Returns the indicated 0-indexed column when the value of $fetchStyle is
     *                                      Query::HYDRATE_COLUMN. Defaults to 0.
     *
     * @return array
     */
    function fetchAll($fetchStyle = \PDO::FETCH_BOTH)
    {
        $rows = array();
        while ($row = $this->fetch($fetchStyle)) {
            $rows[] = $row;
        }
        return $rows;
    }

    /**
     * fetchColumn
     * Returns a single column from the next row of a
     * result set or FALSE if there are no more rows.
     *
     * @param integer $columnIndex          0-indexed number of the column you wish to retrieve from the row. If no
     *                                      value is supplied, PDOStatement->fetchColumn()
     *                                      fetches the first column.
     *
     * @return string                       returns a single column in the next row of a result set.
     */
    function fetchColumn($columnIndex = 0)
    {
        $row = $this->fetch(\PDO::FETCH_NUM);
        if ($row && isset($row[$columnIndex])) {
            return $row[$columnIndex];
        }
        return false;
    }

    /**
     * rowCount
     * rowCount() returns the number of rows affected by the last DELETE, INSERT, or UPDATE statement
     * executed by the corresponding object.
     *
     * If the last SQL statement executed by the associated Statement object was a SELECT statement,
     * some databases may return the number of rows returned by that statement. However,
     * this behaviour is not guaranteed for all databases and should not be
     * relied on for portable applications.
     *
     * @return integer                      Returns the number of rows.
     */
    function rowCount()
    {
        return (@db2_num_rows($this->_stmt))?:0;
    }
}