<?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_Ldap

 * @subpackage Ldif

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

 */

/**

 * Zend_Ldap_Ldif_Encoder provides methods to encode and decode LDAP data into/from LDIF.

 *

 * @category   Zend

 * @package    Zend_Ldap

 * @subpackage Ldif

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

 */

class Zend_Ldap_Ldif_Encoder

{

    /**

     * Additional options used during encoding

     *

     * @var array

     */

    protected $_options = array(

        'sort'    => true,

        'version' => 1,

        'wrap'    => 78

    );

    /**

     * @var boolean

     */

    protected $_versionWritten = false;

    /**

     * Constructor.

     *

     * @param  array $options Additional options used during encoding

     * @return void

     */

    protected function __construct(array $options = array())

    {

        $this->_options = array_merge($this->_options, $options);

    }

    /**

     * Decodes the string $string into an array of LDIF items

     *

     * @param  string $string

     * @return array

     */

    public static function decode($string)

    {

        $encoder = new self(array());

        return $encoder->_decode($string);

    }

    /**

     * Decodes the string $string into an array of LDIF items

     *

     * @param  string $string

     * @return array

     */

    protected function _decode($string)

    {

        $items = array();

        $item = array();

        $last = null;

        foreach (explode("\n", $string) as $line) {

            $line = rtrim($line, "\x09\x0A\x0D\x00\x0B");

            $matches = array();

            if (substr($line, 0, 1) === ' ' && $last !== null) {

                $last[2] .= substr($line, 1);

            } else if (substr($line, 0, 1) === '#') {

                continue;

            } else if (preg_match('/^([a-z0-9;-]+)(:[:<]?\s*)([^:<]*)$/i', $line, $matches)) {

                $name = strtolower($matches[1]);

                $type = trim($matches[2]);

                $value = $matches[3];

                if ($last !== null) {

                    $this->_pushAttribute($last, $item);

                }

                if ($name === 'version') {

                    continue;

                } else if (count($item) > 0 && $name === 'dn') {

                    $items[] = $item;

                    $item = array();

                    $last = null;

                }

                $last = array($name, $type, $value);

            } else if (trim($line) === '') {

                continue;

            }

        }

        if ($last !== null) {

            $this->_pushAttribute($last, $item);

        }

        $items[] = $item;

        return (count($items)>1) ? $items : $items[0];

    }

    /**

     * Pushes a decoded attribute to the stack

     *

     * @param array $attribute

     * @param array $entry

     */

    protected function _pushAttribute(array $attribute, array &$entry)

    {

        $name = $attribute[0];

        $type = $attribute[1];

        $value = $attribute[2];

        if ($type === '::') {

            $value = base64_decode($value);

        }

        if ($name === 'dn') {

            $entry[$name] = $value;

        } else if (isset($entry[$name]) && $value !== '') {

            $entry[$name][] = $value;

        } else {

            $entry[$name] = ($value !== '') ? array($value) : array();

        }

    }

    /**

     * Encode $value into a LDIF representation

     *

     * @param  mixed $value   The value to be encoded

     * @param  array $options Additional options used during encoding

     * @return string The encoded value

     */

    public static function encode($value, array $options = array())

    {

        $encoder = new self($options);

        return $encoder->_encode($value);

    }

    /**

     * Recursive driver which determines the type of value to be encoded

     * and then dispatches to the appropriate method.

     *

     * @param  mixed $value The value to be encoded

     * @return string Encoded value

     */

    protected function _encode($value)

    {

        if (is_scalar($value)) {

            return $this->_encodeString($value);

        } else if (is_array($value)) {

            return $this->_encodeAttributes($value);

        } else if ($value instanceof Zend_Ldap_Node) {

            return $value->toLdif($this->_options);

        }

        return null;

    }

    /**

     * Encodes $string according to RFC2849

     *

     * @link http://www.faqs.org/rfcs/rfc2849.html

     *

     * @param  string $string

     * @param  boolen $base64

     * @return string

     */

    protected function _encodeString($string, &$base64 = null)

    {

        $string = (string)$string;

        if (!is_numeric($string) && empty($string)) {

            return '';

        }

        /*

         * SAFE-INIT-CHAR = %x01-09 / %x0B-0C / %x0E-1F /

         *                  %x21-39 / %x3B / %x3D-7F

         *                ; any value <= 127 except NUL, LF, CR,

         *                ; SPACE, colon (":", ASCII 58 decimal)

         *                ; and less-than ("<" , ASCII 60 decimal)

         *

         */

        $unsafe_init_char = array(0, 10, 13, 32, 58, 60);

        /*

         * SAFE-CHAR      = %x01-09 / %x0B-0C / %x0E-7F

         *                ; any value <= 127 decimal except NUL, LF,

         *                ; and CR

         */

        $unsafe_char      = array(0, 10, 13);

        $base64 = false;

        for ($i = 0; $i < strlen($string); $i++) {

            $char = ord(substr($string, $i, 1));

            if ($char >= 127) {

                $base64 = true;

                break;

            } else if ($i === 0 && in_array($char, $unsafe_init_char)) {

                $base64 = true;

                break;

            } else if (in_array($char, $unsafe_char)) {

                $base64 = true;

                break;

            }

        }

        // Test for ending space

        if (substr($string, -1) == ' ') {

            $base64 = true;

        }

        if ($base64 === true) {

            $string = base64_encode($string);

        }

        return $string;

    }

    /**

     * Encodes an attribute with $name and $value according to RFC2849

     *

     * @link http://www.faqs.org/rfcs/rfc2849.html

     *

     * @param  string       $name

     * @param  array|string $value

     * @return string

     */

    protected function _encodeAttribute($name, $value)

    {

        if (!is_array($value)) {

            $value = array($value);

        }

        $output = '';

        if (count($value) < 1) {

            return $name . ': ';

        }

        foreach ($value as $v) {

            $base64 = null;

            $v = $this->_encodeString($v, $base64);

            $attribute = $name . ':';

            if ($base64 === true) {

                $attribute .= ': ' . $v;

            } else {

                $attribute .= ' ' . $v;

            }

            if (isset($this->_options['wrap']) && strlen($attribute) > $this->_options['wrap']) {

                $attribute = trim(chunk_split($attribute, $this->_options['wrap'], PHP_EOL . ' '));

            }

            $output .= $attribute . PHP_EOL;

        }

        return trim($output, PHP_EOL);

    }

    /**

     * Encodes a collection of attributes according to RFC2849

     *

     * @link http://www.faqs.org/rfcs/rfc2849.html

     *

     * @param  array $attributes

     * @return string

     */

    protected function _encodeAttributes(array $attributes)

    {

        $string = '';

        $attributes = array_change_key_case($attributes, CASE_LOWER);

        if (!$this->_versionWritten && array_key_exists('dn', $attributes) && isset($this->_options['version'])

                && array_key_exists('objectclass', $attributes)) {

            $string .= sprintf('version: %d', $this->_options['version']) . PHP_EOL;

            $this->_versionWritten = true;

        }

        if (isset($this->_options['sort']) && $this->_options['sort'] === true) {

            ksort($attributes, SORT_STRING);

            if (array_key_exists('objectclass', $attributes)) {

                $oc = $attributes['objectclass'];

                unset($attributes['objectclass']);

                $attributes = array_merge(array('objectclass' => $oc), $attributes);

            }

            if (array_key_exists('dn', $attributes)) {

                $dn = $attributes['dn'];

                unset($attributes['dn']);

                $attributes = array_merge(array('dn' => $dn), $attributes);

            }

        }

        foreach ($attributes as $key => $value) {

            $string .= $this->_encodeAttribute($key, $value) . PHP_EOL;

        }

        return trim($string, PHP_EOL);

    }