1 <?php

     2 /**

     3  * @category   Zend

     4  * @package    Zend_Cloud

     5  * @subpackage Infrastructure

     6  * @copyright  Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)

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

     8  */

     9 

    10 

    11 require_once 'Zend/Cloud/Infrastructure/Image.php';

    12 

    13 /**

    14  * List of images

    15  *

    16  * @package    Zend_Cloud

    17  * @subpackage Infrastructure

    18  * @copyright  Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)

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

    20  */

    21 class Zend_Cloud_Infrastructure_ImageList implements Countable, Iterator, ArrayAccess

    22 {

    23     /**

    24      * @var array Array of Zend_Cloud_Infrastructure_Image

    25      */

    26     protected $images = array();

    27 

    28     /**

    29      * @var int Iterator key

    30      */

    31     protected $iteratorKey = 0;

    32 

    33     /**

    34      * The Image adapter (if exists)

    35      * 

    36      * @var object

    37      */

    38     protected $adapter;

    39 

    40     /**

    41      * Constructor

    42      *

    43      * @param  array $list

    44      * @param  null|object $adapter

    45      * @return boolean

    46      */

    47     public function __construct($images, $adapter = null)

    48     {

    49         if (empty($images) || !is_array($images)) {

    50             require_once 'Zend/Cloud/Infrastructure/Exception.php';

    51             throw new Zend_Cloud_Infrastructure_Exception(__CLASS__ . ' expects an array of images');

    52         }

    53 

    54         $this->adapter = $adapter;

    55         $this->constructFromArray($images);

    56     }

    57 

    58     /**

    59      * Transforms the Array to array of Instances

    60      *

    61      * @param  array $list

    62      * @return void

    63      */

    64     protected function constructFromArray(array $list)

    65     {

    66         foreach ($list as $image) {

    67             $this->addImage(new Zend_Cloud_Infrastructure_Image($image, $this->adapter));

    68         }

    69     }

    70 

    71     /**

    72      * Add an image

    73      *

    74      * @param  Image

    75      * @return ImageList

    76      */

    77     protected function addImage(Zend_Cloud_Infrastructure_Image $image)

    78     {

    79         $this->images[] = $image;

    80         return $this;

    81     }

    82 

    83     /**

    84      * Return number of images

    85      *

    86      * Implement Countable::count()

    87      *

    88      * @return int

    89      */

    90     public function count()

    91     {

    92         return count($this->images);

    93     }

    94 

    95     /**

    96      * Return the current element

    97      *

    98      * Implement Iterator::current()

    99      *

   100      * @return Image

   101      */

   102     public function current()

   103     {

   104         return $this->images[$this->iteratorKey];

   105     }

   106 

   107     /**

   108      * Return the key of the current element

   109      *

   110      * Implement Iterator::key()

   111      *

   112      * @return int

   113      */

   114     public function key()

   115     {

   116         return $this->iteratorKey;

   117     }

   118 

   119     /**

   120      * Move forward to next element

   121      *

   122      * Implement Iterator::next()

   123      *

   124      * @return void

   125      */

   126     public function next()

   127     {

   128         $this->iteratorKey++;

   129     }

   130 

   131     /**

   132      * Rewind the Iterator to the first element

   133      *

   134      * Implement Iterator::rewind()

   135      *

   136      * @return void

   137      */

   138     public function rewind()

   139     {

   140         $this->iteratorKey = 0;

   141     }

   142 

   143     /**

   144      * Check if there is a current element after calls to rewind() or next()

   145      *

   146      * Implement Iterator::valid()

   147      *

   148      * @return bool

   149      */

   150     public function valid()

   151     {

   152         $numItems = $this->count();

   153         if ($numItems > 0 && $this->iteratorKey < $numItems) {

   154             return true;

   155         }

   156         return false;

   157     }

   158 

   159     /**

   160      * Whether the offset exists

   161      *

   162      * Implement ArrayAccess::offsetExists()

   163      *

   164      * @param   int     $offset

   165      * @return  bool

   166      */

   167     public function offsetExists($offset)

   168     {

   169         return ($offset < $this->count());

   170     }

   171 

   172     /**

   173      * Return value at given offset

   174      *

   175      * Implement ArrayAccess::offsetGet()

   176      *

   177      * @param   int     $offset

   178      * @throws  Zend_Cloud_Infrastructure_Exception

   179      * @return  Image

   180      */

   181     public function offsetGet($offset)

   182     {

   183         if (!$this->offsetExists($offset)) {

   184             require_once 'Zend/Cloud/Infrastructure/Exception.php';

   185             throw new Zend_Cloud_Infrastructure_Exception('Illegal index');

   186         }

   187         return $this->images[$offset];

   188     }

   189 

   190     /**

   191      * Throws exception because all values are read-only

   192      *

   193      * Implement ArrayAccess::offsetSet()

   194      *

   195      * @param   int     $offset

   196      * @param   string  $value

   197      * @throws  Zend_Cloud_Infrastructure_Exception

   198      */

   199     public function offsetSet($offset, $value)

   200     {

   201         require_once 'Zend/Cloud/Infrastructure/Exception.php';

   202         throw new Zend_Cloud_Infrastructure_Exception('You are trying to set read-only property');

   203     }

   204 

   205     /**

   206      * Throws exception because all values are read-only

   207      *

   208      * Implement ArrayAccess::offsetUnset()

   209      *

   210      * @param   int     $offset

   211      * @throws  Zend_Cloud_Infrastructure_Exception

   212      */

   213     public function offsetUnset($offset)

   214     {

   215         require_once 'Zend/Cloud/Infrastructure/Exception.php';

   216         throw new Zend_Cloud_Infrastructure_Exception('You are trying to unset read-only property');

   217     }

   218 }