improvement: tags replace keywords. Better data model, less

limitations. Each image can be associated to as many tag as needed. Tags can
contain non ASCII characters. Oriented navigation with tags by association.


git-svn-id: http://piwigo.org/svn/trunk@1119 68402e56-0260-453c-a942-63ccdbb3a9ee

1 files changed, 175 insertions, 21 deletions

diff --git a/admin/include/functions.php b/admin/include/functions.php
index dc477f6d1..3a8c6b506 100644
--- a/admin/include/functions.php
+++ b/admin/include/functions.php
@@ -269,6 +269,14 @@ DELETE FROM '.IMAGE_CATEGORY_TABLE.'
 ;';
   pwg_query($query);
 
+  // destruction of the links between images and tags
+  $query = '
+DELETE FROM '.IMAGE_TAG_TABLE.'
+  WHERE image_id IN (
+'.wordwrap(implode(', ', $ids), 80, "\n").')
+;';
+  pwg_query($query);
+
   // destruction of the favorites associated with the picture
   $query = '
 DELETE FROM '.FAVORITES_TABLE.'
@@ -577,25 +585,6 @@ function date_convert_back( $date )
 }
 
 /**
- * returns an array with relevant keywords found in the given string.
- *
- * Keywords must be separated by comma or space characters.
- *
- * @param string keywords_string
- * @return array
- */
-function get_keywords($keywords_string)
-{
-  return
-    array_unique(
-      preg_split(
-        '/[\s,]+/',
-        $keywords_string
-        )
-      );
-}
-
-/**
  * returns an array containing sub-directories which can be a category,
  * recursive by default
  *
@@ -2094,6 +2083,173 @@ UPDATE
 }
 
 /**
+ * Set tags to an image. Warning: given tags are all tags associated to the
+ * image, not additionnal tags.
+ *
+ * @param array tag ids
+ * @param int image id
+ * @return void
+ */
+function set_tags($tags, $image_id)
+{
+  $query = '
+DELETE
+  FROM '.IMAGE_TAG_TABLE.'
+  WHERE image_id = '.$image_id.'
+;';
+  pwg_query($query);
+
+  if (count($tags) > 0)
+  {
+    $inserts = array();
+    foreach ($tags as $tag_id)
+    {
+      array_push(
+        $inserts,
+        array(
+          'tag_id' => $tag_id,
+          'image_id' => $image_id
+          )
+        );
+    }
+    mass_inserts(
+      IMAGE_TAG_TABLE,
+      array_keys($inserts[0]),
+      $inserts
+      );
+  }
+}
+
+/**
+ * Add new tags to a set of images.
+ *
+ * @param array tag ids
+ * @param array image ids
+ * @return void
+ */
+function add_tags($tags, $images)
+{
+  if (count($tags) == 0 or count($tags) == 0)
+  {
+    return;
+  }
+  
+  // we can't insert twice the same {image_id,tag_id} so we must first
+  // delete lines we'll insert later
+  $query = '
+DELETE
+  FROM '.IMAGE_TAG_TABLE.'
+  WHERE image_id IN ('.implode(',', $images).')
+    AND tag_id IN ('.implode(',', $tags).')
+;';
+  pwg_query($query);
+
+  $inserts = array();
+  foreach ($images as $image_id)
+  {
+    foreach ($tags as $tag_id)
+    {
+      array_push(
+        $inserts,
+        array(
+          'image_id' => $image_id,
+          'tag_id' => $tag_id,
+          )
+        );
+    }
+  }
+  mass_inserts(
+    IMAGE_TAG_TABLE,
+    array_keys($inserts[0]),
+    $inserts
+    );
+}
+
+function tag_id_from_tag_name($tag_name)
+{
+  global $page;
+
+  if (isset($page['tag_id_from_tag_name_cache'][$tag_name]))
+  {
+    return $page['tag_id_from_tag_name_cache'][$tag_name];
+  }
+  
+  if (function_exists('mysql_real_escape_string'))
+  {
+    $tag_name = mysql_real_escape_string($tag_name);
+  }
+  else
+  {
+    $tag_name = mysql_escape_string($tag_name);
+  }
+
+  // does the tag already exist?
+  $query = '
+SELECT id
+  FROM '.TAGS_TABLE.'
+  WHERE name = \''.$tag_name.'\'
+;';
+  $existing_tags = array_from_query($query, 'id');
+
+  if (count($existing_tags) == 0)
+  {
+    mass_inserts(
+      TAGS_TABLE,
+      array('name', 'url_name'),
+      array(
+        array(
+          'name' => $tag_name,
+          'url_name' => str2url($tag_name),
+          )
+        )
+      );
+
+    $page['tag_id_from_tag_name_cache'][$tag_name] = mysql_insert_id();
+  }
+  else
+  {
+    $page['tag_id_from_tag_name_cache'][$tag_name] = $existing_tags[0];
+  }
+
+  return $page['tag_id_from_tag_name_cache'][$tag_name];
+}
+
+function set_tags_of($tags_of)
+{
+  if (count($tags_of) > 0)
+  {
+    $query = '
+DELETE
+  FROM '.IMAGE_TAG_TABLE.'
+  WHERE image_id IN ('.implode(',', array_keys($tags_of)).')
+;';
+    pwg_query($query);
+
+    $inserts = array();
+    
+    foreach ($tags_of as $image_id => $tag_ids)
+    {
+      foreach ($tag_ids as $tag_id)
+      {
+        array_push(
+          $inserts,
+          array(
+            'image_id' => $image_id,
+            'tag_id' => $tag_id,
+            )
+          );
+      }
+    }
+
+    mass_inserts(
+      IMAGE_TAG_TABLE,
+      array_keys($inserts[0]),
+      $inserts
+      );
+  }
+}
+
+/**
  * Do maintenance on all PWG tables
  *
  * @return nono
@@ -2143,6 +2299,4 @@ function do_maintenance_all_tables()
   pwg_query($query);
 
 }
-
-
 ?>