Implemented language selection for taxonomy

i18n_select/i18n_select.admin.inc

@@ -34,7 +34,7 @@ function i18n_select_admin_settings() {
   );
   $form['selection']['i18n_select_taxonomy'] = array(
     '#type' => 'checkbox',
-    '#title' => t('Taxonomy (not implemented)'),
+    '#title' => t('Taxonomy'),
     '#default_value' => variable_get('i18n_select_taxonomy', TRUE),
   );
 

i18n_select/i18n_select.module

@@ -1,6 +1,13 @@
 <?php
 // $Id: i18n_select.module,v 1.1.2.1 2010/11/09 10:31:32 brucepearson Exp $
-
+/**
+ * @file
+ * Multilingual content selection module.
+ * 
+ * Alters content queries to add language conditions.
+ * 
+ * Queries tagged with 'i18n_select' or that already have a language condition will not be altered.
+ */
 /**
  * Implementation of hook_menu().
  */
@@ -24,36 +31,33 @@ function i18n_select_menu() {
  * Rewrite node queries so language selection options are enforced.
  */
 function i18n_select_query_node_access_alter(QueryAlterableInterface $query) {
-  if (variable_get('i18n_select_nodes', TRUE) && ($table_alias = i18n_select_check_table($query, 'node'))) {
+  if (variable_get('i18n_select_nodes', TRUE) && ($table_alias = i18n_select_check_table($query, 'node'))  && i18n_select_check_query($query, $table_alias)) {
     // if the language field is present we don't want to do any filtering.
     $fields = $query->getFields();
-    dpm($fields);
-    dpm($query->conditions());
     if (isset($fields['language'])) {
       return;
     }
 
     $language = i18n_select_language();
     $default_lang = language_default('language');
 
-    if (variable_get('i18n_select_missing_translation', FALSE) && $language != $default_lang) {
-
+    if (variable_get('i18n_select_missing_translation', FALSE) && $language != $default_lang) {        
       // we want to include nodes from the default language that haven't been
       // translated to the current language
-
       // SELECT * FROM node n
       //   LEFT JOIN node i18n ON n.tnid > 0 AND n.tnid = i18n.tnid AND i18n.language = 'es'
       //   WHERE n.language='es' OR (n.language='en' AND i18n.nid IS NULL)
-      
+
       // Make sure the conditions refer to the node table. eg using 'n.promote' instead of 'promote'
       i18n_select_check_conditions($query, $table_alias);
 
       $query->leftjoin('node', 'i18n', 'n.tnid > 0 AND n.tnid = i18n.tnid AND i18n.language = :lang', array(':lang' => $language));
       $query->where($table_alias . '.language=:lang OR (' . $table_alias . '.language=:default_lang AND i18n.nid IS NULL)', array(':lang' => $language, ':default_lang' => $default_lang));
-
     } else {
       $query->where($table_alias . '.language=:lang', array(':lang' => $language));
     }
+    // Mark query as altered
+    $query->addTag('i18n_select');
   }
 }
 
@@ -63,13 +67,17 @@ function i18n_select_query_node_access_alter(QueryAlterableInterface $query) {
  * Rewrite taxonomy term queries so language selection options are enforced.
  */
 function i18n_select_query_term_access_alter(QueryAlterableInterface $query) {
-  if (variable_get('i18n_select_taxonomy', TRUE) && ($table_alias = i18n_select_check_table($query, 'taxonomy_term_data'))) {
-    $query->condition($table_alias . '.language', i18n_select_language()); 
+  if (variable_get('i18n_select_taxonomy', TRUE) && ($table_alias = i18n_select_check_table($query, 'taxonomy_term_data')) && i18n_select_check_query($query, $table_alias)) {
+    $query->condition($table_alias . '.language', i18n_select_langcodes());
+    // Mark query as altered
+    $query->addTag('i18n_select');
   }
 }
 
 /**
  * Check table exists in query and get alias for it
+ * 
+ * @todo Should we add the table if not there?
  */
 function i18n_select_check_table($query, $table_name) {
   foreach ($query->getTables() as $table) {
@@ -94,8 +102,37 @@ function i18n_select_check_conditions($query, $table_alias) {
 }
 
 /**
- * Get language code for content selection
+ * Check whether we should apply language conditions here:
+ * - The query has not been tagged with 'i18n_select'
+ * - The query doesn't include a language field for selection ??
+ * - The query doesn't have already a language condition
+ */
+function i18n_select_check_query($query, $table_alias, $field_name = 'language') {
+  if (!$query->hasTag('i18n_select')) {
+    $fields = $query->getFields();
+    $table_field = $table_alias . '.' . $field_name;
+    if (isset($fields[$field_name]) || isset($fields[$table_field])) {
+      return FALSE;
+    }
+    foreach ($query->conditions() as $condition) {
+      if (is_array($condition) && isset($condition['field']) && ($condition['field'] == $field_name || $condition['field'] == $table_field)) {
+        return FALSE;
+      }
+    }
+    return TRUE;
+  }
+}
+
+/**
+ * Get main language code for content selection
  */
 function i18n_select_language() {
   return $GLOBALS['language_content']->language;
+}
+
+/**
+ * Get language codes for content selection to use in query conditions
+ */
+function i18n_select_langcodes() {
+  return array(i18n_select_language(), LANGUAGE_NONE);
 }