source: trunk/include/functions_tag.inc.php @ 14086

Last change on this file since 14086 was 12922, checked in by mistic100, 13 years ago

update Piwigo headers to 2012, last change before the expected (or not) apocalypse

  • Property svn:eol-style set to LF
File size: 8.0 KB
Line 
1<?php
2// +-----------------------------------------------------------------------+
3// | Piwigo - a PHP based photo gallery                                    |
4// +-----------------------------------------------------------------------+
5// | Copyright(C) 2008-2012 Piwigo Team                  http://piwigo.org |
6// | Copyright(C) 2003-2008 PhpWebGallery Team    http://phpwebgallery.net |
7// | Copyright(C) 2002-2003 Pierrick LE GALL   http://le-gall.net/pierrick |
8// +-----------------------------------------------------------------------+
9// | This program is free software; you can redistribute it and/or modify  |
10// | it under the terms of the GNU General Public License as published by  |
11// | the Free Software Foundation                                          |
12// |                                                                       |
13// | This program is distributed in the hope that it will be useful, but   |
14// | WITHOUT ANY WARRANTY; without even the implied warranty of            |
15// | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      |
16// | General Public License for more details.                              |
17// |                                                                       |
18// | You should have received a copy of the GNU General Public License     |
19// | along with this program; if not, write to the Free Software           |
20// | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
21// | USA.                                                                  |
22// +-----------------------------------------------------------------------+
23
24
25/**
26 * Tags available. Each return tag is represented as an array with its id,
27 * its name, its weight (count), its url name. Tags are not sorted.
28 *
29 * The returned list can be a subset of all existing tags due to
30 * permissions, only if a list of forbidden categories is provided
31 *
32 * @param array forbidden categories
33 * @return array
34 */
35function get_available_tags()
36{
37  // we can find top fatter tags among reachable images
38  $query = '
39SELECT tag_id, COUNT(DISTINCT(it.image_id)) AS counter
40  FROM '.IMAGE_CATEGORY_TABLE.' ic
41    INNER JOIN '.IMAGE_TAG_TABLE.' it ON ic.image_id=it.image_id'.get_sql_condition_FandF
42    (
43      array
44        (
45          'forbidden_categories' => 'category_id',
46          'visible_categories' => 'category_id',
47          'visible_images' => 'ic.image_id'
48        ),
49      '
50  WHERE'
51    ).'
52  GROUP BY tag_id';
53  $tag_counters = simple_hash_from_query($query, 'tag_id', 'counter');
54
55  if ( empty($tag_counters) )
56  {
57    return array();
58  }
59
60  $query = '
61SELECT *
62  FROM '.TAGS_TABLE;
63  $result = pwg_query($query);
64  $tags = array();
65  while ($row = pwg_db_fetch_assoc($result))
66  {
67    $counter = @$tag_counters[ $row['id'] ];
68    if ( $counter )
69    {
70      $row['counter'] = $counter;
71      $row['name'] = trigger_event('render_tag_name', $row['name']);
72      array_push($tags, $row);
73    }
74  }
75  return $tags;
76}
77
78/**
79 * All tags, even tags associated to no image.
80 *
81 * @return array
82 */
83function get_all_tags()
84{
85  $query = '
86SELECT *
87  FROM '.TAGS_TABLE.'
88;';
89  $result = pwg_query($query);
90  $tags = array();
91  while ($row = pwg_db_fetch_assoc($result))
92  {
93    $row['name'] = trigger_event('render_tag_name', $row['name']);
94    array_push($tags, $row);
95  }
96
97  usort($tags, 'tag_alpha_compare');
98
99  return $tags;
100}
101
102/**
103 * Giving a set of tags with a counter for each one, calculate the display
104 * level of each tag.
105 *
106 * The level of each tag depends on the average count of tags. This
107 * calcylation method avoid having very different levels for tags having
108 * nearly the same count when set are small.
109 *
110 * @param array tags
111 * @return array
112 */
113function add_level_to_tags($tags)
114{
115  global $conf;
116
117  if (count($tags) == 0)
118  {
119    return $tags;
120  }
121
122  $total_count = 0;
123
124  foreach ($tags as $tag)
125  {
126    $total_count+= $tag['counter'];
127  }
128
129  // average count of available tags will determine the level of each tag
130  $tag_average_count = $total_count / count($tags);
131
132  // tag levels threshold calculation: a tag with an average rate must have
133  // the middle level.
134  for ($i = 1; $i < $conf['tags_levels']; $i++)
135  {
136    $threshold_of_level[$i] =
137      2 * $i * $tag_average_count / $conf['tags_levels'];
138  }
139
140  // display sorted tags
141  foreach (array_keys($tags) as $k)
142  {
143    $tags[$k]['level'] = 1;
144
145    // based on threshold, determine current tag level
146    for ($i = $conf['tags_levels'] - 1; $i >= 1; $i--)
147    {
148      if ($tags[$k]['counter'] > $threshold_of_level[$i])
149      {
150        $tags[$k]['level'] = $i + 1;
151        break;
152      }
153    }
154  }
155
156  return $tags;
157}
158
159/**
160 * return the list of image ids corresponding to given tags. AND & OR mode
161 * supported.
162 *
163 * @param array tag ids
164 * @param string mode
165 * @param string extra_images_where_sql - optionally apply a sql where filter to retrieved images
166 * @param string order_by - optionally overwrite default photo order
167 * @return array
168 */
169function get_image_ids_for_tags($tag_ids, $mode='AND', $extra_images_where_sql='', $order_by='', $use_permissions=true)
170{
171  global $conf;
172  if (empty($tag_ids))
173  {
174    return array();
175  }
176
177  $query = 'SELECT id
178  FROM '.IMAGES_TABLE.' i ';
179
180  if ($use_permissions)
181  {
182    $query.= '
183    INNER JOIN '.IMAGE_CATEGORY_TABLE.' ic ON id=ic.image_id';
184  }
185
186  $query.= '
187    INNER JOIN '.IMAGE_TAG_TABLE.' it ON id=it.image_id
188    WHERE tag_id IN ('.implode(',', $tag_ids).')';
189
190  if ($use_permissions)
191  {
192    $query.= get_sql_condition_FandF(
193      array(
194        'forbidden_categories' => 'category_id',
195        'visible_categories' => 'category_id',
196        'visible_images' => 'id'
197        ),
198      "\n  AND"
199      );
200  }
201
202  $query.= (empty($extra_images_where_sql) ? '' : " \nAND (".$extra_images_where_sql.')').'
203  GROUP BY id';
204 
205  if ($mode=='AND' and count($tag_ids)>1)
206  {
207    $query .= '
208  HAVING COUNT(DISTINCT tag_id)='.count($tag_ids);
209  }
210  $query .= "\n".(empty($order_by) ? $conf['order_by'] : $order_by);
211
212  return array_from_query($query, 'id');
213}
214
215/**
216 * return a list of tags corresponding to given items.
217 *
218 * @param array items
219 * @param array max_tags
220 * @param array excluded_tag_ids
221 * @return array
222 */
223function get_common_tags($items, $max_tags, $excluded_tag_ids=null)
224{
225  if (empty($items))
226  {
227    return array();
228  }
229  $query = '
230SELECT t.*, count(*) AS counter
231  FROM '.IMAGE_TAG_TABLE.'
232    INNER JOIN '.TAGS_TABLE.' t ON tag_id = id
233  WHERE image_id IN ('.implode(',', $items).')';
234  if (!empty($excluded_tag_ids))
235  {
236    $query.='
237    AND tag_id NOT IN ('.implode(',', $excluded_tag_ids).')';
238  }
239  $query .='
240  GROUP BY t.id
241  ORDER BY ';
242  if ($max_tags>0)
243  {
244    $query .= 'counter DESC
245  LIMIT '.$max_tags;
246  }
247  else
248  {
249    $query .= 'NULL';
250  }
251
252  $result = pwg_query($query);
253  $tags = array();
254  while($row = pwg_db_fetch_assoc($result))
255  {
256    $row['name'] = trigger_event('render_tag_name', $row['name']);
257    array_push($tags, $row);
258  }
259  usort($tags, 'tag_alpha_compare');
260  return $tags;
261}
262
263/**
264 * return a list of tags corresponding to any of ids, url_names, names
265 *
266 * @param array ids
267 * @param array url_names
268 * @param array names
269 * @return array
270 */
271function find_tags($ids, $url_names=array(), $names=array() )
272{
273  $where_clauses = array();
274  if ( !empty($ids) )
275  {
276    $where_clauses[] = 'id IN ('.implode(',', $ids).')';
277  }
278  if ( !empty($url_names) )
279  {
280    $where_clauses[] =
281      'url_name IN ('.
282      implode(
283        ',',
284        array_map(
285          create_function('$s', 'return "\'".$s."\'";'),
286          $url_names
287          )
288        )
289      .')';
290  }
291  if ( !empty($names) )
292  {
293    $where_clauses[] =
294      'name IN ('.
295      implode(
296        ',',
297        array_map(
298          create_function('$s', 'return "\'".$s."\'";'),
299          $names
300          )
301        )
302      .')';
303  }
304  if (empty($where_clauses))
305  {
306    return array();
307  }
308
309  $query = '
310SELECT *
311  FROM '.TAGS_TABLE.'
312  WHERE '. implode( '
313    OR ', $where_clauses);
314
315  $result = pwg_query($query);
316  $tags = array();
317  while ($row = pwg_db_fetch_assoc($result))
318  {
319    array_push($tags, $row);
320  }
321  return $tags;
322}
323?>
Note: See TracBrowser for help on using the repository browser.