Type/module/content/picasa2.php

   1 <?php
   2 /* vim: set expandtab shiftwidth=4 softtabstop=4 tabstop=4 foldmethod=marker: */
   3
   4 /**
   5  * TIP_Picasa2 photo access
   6  *
   7  * LICENSE: This source file is subject to the New BSD license that is
   8  * available through the world-wide-web at the following URI:
   9  * http://www.opensource.org/licenses/bsd-license.php
  10  * If you did not receive a copy of the New BSD License and are unable to
  11  * obtain it through the web, please send a note to license@php.net so we
  12  * can mail you a copy immediately.
  13  *
  14  * @author    Nicola Fontana <ntd@entidi.it>
  15  * @copyright Copyright &copy; 2010 Nicola Fontana
  16  * @license   http://www.opensource.org/licenses/bsd-license.php New BSD License
  17  * @package   TIP
  18  * @since     0.3.4
  19  */
  20
  21 /**
  22  * A content module to access picasa version 2 photo throught its album feed
  23  *
  24  * A TIP_Content implementation that sets a default data engine
  25  * capable to directly parse picasa album feed (version 2) to get
  26  * metadata of photos.
  27  *
  28  * To be able to use this module, you should configure a picasa2
  29  * module in your configuration options and feed it with the URI
  30  * of the feed of a picasa album:
  31  *
  32  * <code>
  33  * $cfg = array(
  34  *     ...
  35  *     'picture'  => array(
  36  *         'type' => array('module', 'content', 'picasa2'),
  37  *         'data' => 'http://picasaweb.google.com/data/feed/base/user/.../albumid/...'
  38  *     )
  39  *     ...
  40  * );
  41  * </code>
  42  *
  43  * The TIP_Picasa2 access to the feed is read-only but you need
  44  * to fulfill the PicasaWeb Terms of Service in order to be allowed
  45  * to access the feed:
  46  *
  47  * http://code.google.com/apis/picasaweb/terms.html
  48  *
  49  * After configuring it, you can use your newly "picture" module in
  50  * the same way a common TIP_Content module is used.
  51  *
  52  * To be able to access the feed, TIP_Picasa2 considers any
  53  * <entry> in the feed as any SQL engine treats a row in a table.
  54  * The field of this virtual row are mapped to a usable field id
  55  * using the "fields_xpath" property of the TIP_XML engine. Here
  56  * it is a (probably outdated) list of these virtual fields
  57  * (together with the XPath used to map their value):
  58  *
  59  * - **id** ({{link[contains(@rel,"#canonical")]/@href}})
  60  * - **title** ({{media:group/media:title[@type="plain"]}})
  61  * - **description** ({{media:group/media:description[@type="plain"]}})
  62  * - **imageurl** ({{media:group/media:content[@medium="image"]/@url}})
  63  * - **thumbnail** ({{media:group/media:thumbnail[3]/@url}})
  64  * - **thumbnail_width** ({{media:group/media:thumbnail[3]/@width}})
  65  * - **thumbnail_height** ({{media:group/media:thumbnail[3]/@height}})
  66  * - **date** ({{published}})
  67  * - **author** ({{../author/name}})
  68  * - **uploader** ({{media:group/media:credit}})
  69  *
  70  * Adding new field mapping is trivial: up to now it was added what
  71  * I actually need.
  72  *
  73  * The above fields can be used in you templates just as every other
  74  * field provided by the more usual TIP_Mysql engine. For instance,
  75  * to get a list of the first 5 items, you can do something like this:
  76  *
  77  * <code>
  78  * <ul class="picture">{picture.forSelect(LIMIT 5)}
  79  *   <li><a href="{imageurl}">
  80  *     <img src="{thumbnail}" width="{thumbnail_width}" height="{thumbnail_height}" alt="{description}" />
  81  *   </li>{}
  82  * </ul>
  83  * </code>
  84  *
  85  * Because TIP_Picasa2 accesses the underlying feed using the TIP_XML
  86  * data engine there are some known restriction: for instance,
  87  * you can't do a complex SQL query using the ORDER BY or GROUP BY
  88  * clauses. Check the TIP_XML documentation to exactly know which
  89  * queries can be executed.
  90  *
  91  * @package TIP
  92  */
  93 class TIP_Picasa2 extends TIP_Content
  94 {
  95     //{{{ Construction/destruction
  96
  97     static protected function checkOptions(&$options)
  98     {
  99         if (@is_string($options['data'])) {
 100             $options['data'] = array('path' => $options['data']);
 101         }
 102
 103         // The data path is a required option
 104         if (!@is_array($options['data']) || !isset($options['data']['path'])) {
 105             return false;
 106         }
 107
 108         TIP::arrayDefault($options, 'id_type', 'string');
 109         TIP::arrayDefault($options['data'], 'data_engine', array(
 110             'id'                    => 'picasa2',
 111             'type'                  => array('data_engine', 'xml'),
 112             'fields_xpath'          => array(
 113                 'id'                => 'link[contains(@rel,"#canonical")]/@href',
 114                 'title'             => 'media:group/media:title[@type="plain"]',
 115                 'description'       => 'media:group/media:description[@type="plain"]',
 116                 'imageurl'          => 'media:group/media:content[@medium="image"]/@url',
 117                 'thumbnail'         => 'media:group/media:thumbnail[3]/@url',
 118                 'thumbnail_width'   => 'media:group/media:thumbnail[3]/@width',
 119                 'thumbnail_height'  => 'media:group/media:thumbnail[3]/@height',
 120                 'date'              => 'published',
 121                 'author'            => '../author/name',
 122                 'uploader'          => 'media:group/media:credit'
 123         )));
 124
 125         return parent::checkOptions($options);
 126     }
 127
 128     /**
 129      * Constructor
 130      *
 131      * Initializes a TIP_Picasa2 instance.
 132      *
 133      * @param array $options Properties values
 134      */
 135     protected function __construct($options)
 136     {
 137         parent::__construct($options);
 138     }
 139
 140     //}}}
 141     //{{{ Methods
 142
 143     /**
 144      * Get the html code for a PicasaWeb picture
 145      *
 146      * Renders the provided PicasaWeb URI (in the canonical form,
 147      * usually something like http://picasaweb.google.com/lh/photo/...)
 148      * to the proper <a ...><img ... /></a> element.
 149      *
 150      * This method starts (and ends) a view to find the row, so any
 151      * further request is cached.
 152      *
 153      * @param  string       $id  The PicasaWeb URI of the photo
 154      * @return string|false      The string to render or false on errors
 155      */
 156     public function toHtml($id)
 157     {
 158         if (is_null($view =& $this->startDataView($this->getData()->rowFilter($id)))) {
 159             TIP::notifyError('select');
 160             return false;
 161         }
 162
 163         $rows =& $view->getProperty('rows');
 164         if (!@array_key_exists($id, $rows))
 165             return false;
 166
 167         return self::_renderRow($rows[$id], array('class' => 'picasa2'));
 168     }
 169
 170     /**
 171      * Get the html code for the whole PicasaWeb album
 172      *
 173      * Renders all the photo included by this album.
 174      *
 175      * @return string|false  The string to render or false on errors
 176      */
 177     public function toHtmlAlbum()
 178     {
 179         static $cnt = 1;
 180
 181         if (is_null($view =& $this->startDataView())) {
 182             TIP::notifyError('select');
 183             return false;
 184         }
 185
 186         $rows =& $view->getProperty('rows');
 187         $output = '';
 188         $max_width = 0;
 189         $max_height = 0;
 190         $options = array(
 191             'max-width' => &$max_width,
 192             'max-height' => &$max_height
 193         );
 194
 195         foreach ($rows as $row) {
 196             $output .= '  <li>' . self::_renderRow($row, $options) . '</li>';
 197         }
 198
 199         if (empty($output))
 200             return false;
 201
 202         $id = 'Album' . $cnt;
 203         ++$cnt;
 204
 205         $output = <<<EOT
 206 <div class="caption" style="float: right">
 207 <ul id="$id">
 208 $output
 209 </ul>
 210 <p class="caption-title"><a id="$id-prev" href="#">« PRECEDENTE</a> <a id="$id-next" href="#">SEGUENTE »</a></p>
 211 </div>
 212 <script type="text/javascript">
 213     jQuery(function() {
 214         jQuery('#$id').ulslide({
 215             width: $max_width,
 216             height: $max_height,
 217             bprev: '#$id-prev',
 218             bnext: '#$id-next',
 219             axis: 'x'
 220         });
 221     });
 222 </script>
 223 EOT;
 224
 225         return $output;
 226     }
 227
 228     static private function _renderRow($row, $options = null)
 229     {
 230         $id = TIP::toHtml($row['id']);
 231         $description = TIP::toHtml($row['description']);
 232         $src = TIP::toHtml($row['thumbnail']);
 233         $width = (int) $row['thumbnail_width'];
 234         $height = (int) $row['thumbnail_height'];
 235
 236         $attrs = 'href="' . $id . '"';
 237         empty($description) || $attrs .= ' title="' . $description . '"';
 238         isset($options['class']) && $attrs .= ' class="' . $options['class'] . '"';
 239
 240         if (isset($options['max-width']) && $width > $options['max-width'])
 241             $options['max-width'] = $width;
 242         if (isset($options['max-height']) && $height > $options['max-height'])
 243             $options['max-height'] = $height;
 244
 245         return "<a $attrs><img src=\"$src\" width=\"$width\" height=\"$height\" alt=\"$description\" /></a>\n";
 246     }
 247
 248     //}}}
 249 }
 250 ?>