<?php

/**

 * 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_Cloud

 * @subpackage DocumentService

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

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

 */

/**

 * Class encapsulating documents. Fields are stored in a name/value

 * array. Data are represented as strings.

 *

 * TODO Can fields be large enough to warrant support for streams?

 *

 * @category   Zend

 * @package    Zend_Cloud

 * @subpackage DocumentService

 * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

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

 */

class Zend_Cloud_DocumentService_Document 

    implements ArrayAccess, IteratorAggregate, Countable

{

    /** key in document denoting identifier */

    const KEY_FIELD = '_id';

    /**

     * ID of this document.

     * @var mixed

     */

    protected $_id;

    /**

     * Name/value array of field names to values.

     * @var array

     */

    protected $_fields;

    /**

     * Construct an instance of Zend_Cloud_DocumentService_Document.

     *

     * If no identifier is provided, but a field matching KEY_FIELD is present,

     * then that field's value will be used as the document identifier.

     *

     * @param  array $fields

     * @param  mixed $id Document identifier

     * @return void

     */

    public function __construct($fields, $id = null)

    {

        if (!is_array($fields) && !$fields instanceof ArrayAccess) {

            require_once 'Zend/Cloud/DocumentService/Exception.php';

            throw new Zend_Cloud_DocumentService_Exception('Fields must be an array or implement ArrayAccess');

        }

        if (isset($fields[self::KEY_FIELD])) {

            $id = $fields[self::KEY_FIELD];

            unset($fields[self::KEY_FIELD]);

        }

        $this->_fields = $fields;

        $this->setId($id);

    }

    /**

     * Set document identifier

     * 

     * @param  mixed $id 

     * @return Zend_Cloud_DocumentService_Document

     */

    public function setId($id)

    {

        $this->_id = $id;

        return $this;

    }

    /**

     * Get ID name.

     *

     * @return string

     */

    public function getId() 

    {

        return $this->_id;

    }

    /**

     * Get fields as array.

     *

     * @return array

     */

    public function getFields() 

    {

        return $this->_fields;

    }

    /**

     * Get field by name.

     *

     * @param  string $name

     * @return mixed

     */

    public function getField($name)

    {

        if (isset($this->_fields[$name])) {

            return $this->_fields[$name];

        }

        return null;

    }

    /**

     * Set field by name.

     *

     * @param  string $name

     * @param  mixed $value

     * @return Zend_Cloud_DocumentService_Document

     */

    public function setField($name, $value) 

    {

        $this->_fields[$name] = $value;

        return $this;

    }

    /**

     * Overloading: get value

     * 

     * @param  string $name 

     * @return mixed

     */

    public function __get($name)

    {

        return $this->getField($name);

    }

    /**

     * Overloading: set field

     * 

     * @param  string $name 

     * @param  mixed $value 

     * @return void

     */

    public function __set($name, $value)

    {

        $this->setField($name, $value);

    }

    /**

     * ArrayAccess: does field exist?

     * 

     * @param  string $name 

     * @return bool

     */

    public function offsetExists($name)

    {

        return isset($this->_fields[$name]);

    }

    /**

     * ArrayAccess: get field by name

     * 

     * @param  string $name 

     * @return mixed

     */

    public function offsetGet($name)

    {

        return $this->getField($name);

    }

    /**

     * ArrayAccess: set field to value

     * 

     * @param  string $name 

     * @param  mixed $value 

     * @return void

     */

    public function offsetSet($name, $value)

    {

        $this->setField($name, $value);

    }

    /**

     * ArrayAccess: remove field from document

     * 

     * @param  string $name 

     * @return void

     */

    public function offsetUnset($name)

    {

        if ($this->offsetExists($name)) {

            unset($this->_fields[$name]);

        }

    }

    /**

     * Overloading: retrieve and set fields by name

     * 

     * @param  string $name 

     * @param  mixed $args 

     * @return mixed

     */

    public function __call($name, $args)

    {

        $prefix = substr($name, 0, 3);

        if ($prefix == 'get') {

            // Get value

            $option = substr($name, 3);

            return $this->getField($option);

        } elseif ($prefix == 'set') {

            // set value

            $option = substr($name, 3);

            return $this->setField($option, $args[0]);

        }

        require_once 'Zend/Cloud/OperationNotAvailableException.php';

        throw new Zend_Cloud_OperationNotAvailableException("Unknown operation $name");

    }

    /**

     * Countable: return count of fields in document

     * 

     * @return int

     */

    public function count()

    {

        return count($this->_fields);

    }

    /**

     * IteratorAggregate: return iterator for iterating over fields

     * 

     * @return Iterator

     */

    public function getIterator()

    {

        return new ArrayIterator($this->_fields);

    }

}