Implement a basic tag management interface with the organize drawer

modules/tag/controllers/tags.php

@@ -76,4 +76,120 @@ class Tags_Controller extends REST_Controller {
 
     return tag::get_add_form($item);
   }
+
+  public function organize() {
+    access::verify_csrf();
+
+    $itemids = explode("|", Input::instance()->post("item"));
+    $form = tag::get_organize_form($itemids);
+    $old_tags = $form->tags->value;
+    if ($form->validate()) {
+
+      $old_tags = preg_split("/[;,\s]+/", $old_tags);
+      sort($old_tags);
+      $new_tags = preg_split("/[;,\s]+/", $form->tags->value);
+      sort($new_tags);
+
+      $HIGH_VALUE_STRING = "\256";
+      for ($old_index = $new_index = 0;;) {
+        $old_tag = $old_index >= count($old_tags) ? $HIGH_VALUE_STRING : $old_tags[$old_index];
+        $new_tag = $new_index >= count($new_tags) ? $HIGH_VALUE_STRING : $new_tags[$new_index];
+        if ($old_tag == $HIGH_VALUE_STRING && $new_tag == $HIGH_VALUE_STRING) {
+          break;
+        }
+        $matches = array();
+        $old_star = false;
+        if (preg_match("/(.*)(\*)$/", $old_tag, $matches)) {
+          $old_star = true;
+          $old_tag = $matches[1];
+        }
+        $new_star = false;
+        if (preg_match("/(.*)(\*)$/", $new_tag, $matches)) {
+          $new_star = true;
+          $new_tag = $matches[1];
+        }
+        if ($old_tag > $new_tag) {
+          // Its missing in the old list so add it
+          $this->_add_tag($new_tag, $itemids);
+          $new_index++;
+        } else if ($old_tag < $new_tag) {
+          // Its missing in the new list so its been removed
+          $this->_delete_tag($old_tag, $itemids);
+          $old_index++;
+        } else {
+          if ($old_star && !$new_star) {
+            // User wants tag to apply to all items, originally only on some of selected
+            $this->_update_tag($old_tag, $itemids);
+         } // Not changed ignore
+          $old_index++;
+          $new_index++;
+        }
+      }
+    }
+    print json_encode(array("form" => $form->__toString(), "message" => t("Tags updated")));
+  }
+
+  public function reset_organize() {
+    $itemids = Input::instance()->get("item");
+
+    print tag::get_organize_form($itemids);
+  }
+
+  private function _add_tag($new_tag, $itemids) {
+    $tag = ORM::factory("tag")
+      ->where("name", $new_tag)
+      ->find();
+    if ($tag->loaded) {
+      $tag->count += count($itemids);
+    } else {
+      $tag->name = $new_tag;
+      $tag->count = count($itemids);
+    }
+    $tag->save();
+
+    $db = Database::instance();
+    foreach ($itemids as $item_id) {
+      $db->query("INSERT INTO {items_tags} SET item_id = $item_id, tag_id = {$tag->id};");
+    }
+  }
+
+  private function _delete_tag($new_tag, $itemids) {
+    $tag = ORM::factory("tag")
+      ->where("name", $new_tag)
+      ->find();
+    $tag->count -= count($itemids);
+    if ($tag->count > 0) {
+      $tag->save();
+    } else {
+      $tag->delete();
+    }
+
+    $ids = implode(", ", $itemids);
+    Database::instance()->query(
+      "DELETE FROM {items_tags} WHERE tag_id = {$tag->id} AND item_id IN ($ids);");
+  }
+
+  private function _update_tag($new_tag, $itemids) {
+    $tag = ORM::factory("tag")
+      ->where("name", $new_tag)
+      ->find();
+
+    $db = Database::instance();
+    $ids = implode(", ", $itemids);
+    $result = $db->query(
+      "SELECT item_id FROM {items_tags}
+        WHERE tag_id = {$tag->id}
+          AND item_id IN ($ids)");
+
+    $add_items = array_fill_keys($itemids, 1);
+    foreach($result as $row) {
+      unset($add_items[$row->item_id]);
+    }
+    $add_items = array_keys($add_items);
+    $tag->count += count($add_items);
+    $tag->save();
+    foreach ($add_items as $item_id) {
+      $db->query("INSERT INTO {items_tags} SET item_id = $item_id, tag_id = {$tag->id};");
+    }
+  }
 }

modules/tag/helpers/tag.php

@@ -104,4 +104,27 @@ class tag_Core {
     $group->submit("")->value(t("Delete Tag"));
     return $form;
   }
-}
+
+  static function get_organize_form($itemids) {
+    $tagPane = new Forge("tags/__FUNCTION__", "", "post",
+                             array("id" => "gEditTags", "ref" => "organize"));
+    $tagPane->hidden("item")->value(implode("|", $itemids));
+    $item_count = count($itemids);
+    $ids = implode(", ", $itemids);
+    $tags = Database::instance()->query(
+      "SELECT t.name, COUNT(it.item_id) as count
+         FROM {items_tags} it, {tags} t
+        WHERE it.tag_id = t.id
+          AND it.item_id in($ids)
+       GROUP BY it.tag_id
+       ORDER BY t.name ASC");
+    $taglist = array();
+    foreach ($tags as $tag) {
+      $taglist[] = $tag->name . ($item_count > $tag->count ? "*" : "");
+    }
+    $taglist = implode("; ", $taglist);
+    $tagPane->textarea("tags")->label(t("Tags"))->value($taglist);
+
+    return $tagPane;
+  }
+}

modules/tag/helpers/tag_event.php

@@ -59,4 +59,9 @@ class tag_event_Core {
                "SELECT `tag_id` from {items_tags} WHERE `item_id` = $item->id)");
     $db->delete("items_tags", array("item_id" => "$item->id"));
   }
+
+  static function organize_form_creation($event_parms) {
+    $event_parms->panes[] = array("label" => t("Manage Tags"),
+                                  "content" => tag::get_organize_form($event_parms->itemids));
+  }
 }