Add get tags API

appinfo/routes.php

@@ -20,6 +20,7 @@ return [
         ['name' => 'api#days', 'url' => '/api/days', 'verb' => 'GET'],
         ['name' => 'api#dayPost', 'url' => '/api/days', 'verb' => 'POST'],
         ['name' => 'api#day', 'url' => '/api/days/{id}', 'verb' => 'GET'],
+        ['name' => 'api#tags', 'url' => '/api/tags', 'verb' => 'GET'],
         ['name' => 'api#imageInfo', 'url' => '/api/info/{id}', 'verb' => 'GET'],
         ['name' => 'api#imageEdit', 'url' => '/api/edit/{id}', 'verb' => 'PATCH'],
         ['name' => 'api#archive', 'url' => '/api/archive/{id}', 'verb' => 'PATCH'],

lib/Controller/ApiController.php

@@ -261,6 +261,31 @@ class ApiController extends Controller {
         ];
     }
 
+    /**
+     * @NoAdminRequired
+     *
+     * Get list of tags with counts of images
+     * @return JSONResponse
+     */
+    public function tags(): JSONResponse {
+        $user = $this->userSession->getUser();
+        if (is_null($user)) {
+            return new JSONResponse([], Http::STATUS_PRECONDITION_FAILED);
+        }
+
+        // If this isn't the timeline folder then things aren't going to work
+        $folder = $this->getRequestFolder();
+        if (is_null($folder)) {
+            return new JSONResponse([], Http::STATUS_NOT_FOUND);
+        }
+
+        // Run actual query
+        $list = $this->timelineQuery->getTags(
+            $folder,
+        );
+        return new JSONResponse($list, Http::STATUS_OK);
+    }
+
     /**
      * @NoAdminRequired
      *

lib/Db/TimelineQuery.php

@@ -8,6 +8,7 @@ use OCP\IDBConnection;
 class TimelineQuery {
     use TimelineQueryDays;
     use TimelineQueryFilters;
+    use TimelineQueryTags;
 
     protected IDBConnection $connection;
 

lib/Db/TimelineQueryFilters.php

@@ -44,26 +44,4 @@ trait TimelineQueryFilters {
     public function transformVideoFilter(IQueryBuilder &$query, string $userId) {
         $query->andWhere($query->expr()->eq('m.isvideo', $query->createNamedParameter('1')));
     }
-
-    public function getSystemTagId(IQueryBuilder &$query, string $tagName) {
-        $sqb = $query->getConnection()->getQueryBuilder();
-        return $sqb->select('id')->from('systemtag')->where(
-            $sqb->expr()->andX(
-                $sqb->expr()->eq('name', $sqb->createNamedParameter($tagName)),
-                $sqb->expr()->eq('visibility', $sqb->createNamedParameter(1)),
-            ))->executeQuery()->fetchOne();
-    }
-
-    public function transformTagFilter(IQueryBuilder &$query, string $userId, string $tagName) {
-        $tagId = $this->getSystemTagId($query, $tagName);
-        if ($tagId === FALSE) {
-            $tagId = 0; // cannot abort here; that will show up everything in the response
-        }
-
-        $query->innerJoin('m', 'systemtag_object_mapping', 'stom', $query->expr()->andX(
-            $query->expr()->eq('stom.objecttype', $query->createNamedParameter("files")),
-            $query->expr()->eq('stom.objectid', 'm.fileid'),
-            $query->expr()->eq('stom.systemtagid', $query->createNamedParameter($tagId)),
-        ));
-    }
 }

lib/Db/TimelineQueryTags.php

@@ -0,0 +1,63 @@
+<?php
+declare(strict_types=1);
+
+namespace OCA\Memories\Db;
+
+use OCP\IDBConnection;
+use OCP\DB\QueryBuilder\IQueryBuilder;
+use OCP\Files\Folder;
+
+trait TimelineQueryTags {
+    protected IDBConnection $connection;
+
+    public function getSystemTagId(IQueryBuilder &$query, string $tagName) {
+        $sqb = $query->getConnection()->getQueryBuilder();
+        return $sqb->select('id')->from('systemtag')->where(
+            $sqb->expr()->andX(
+                $sqb->expr()->eq('name', $sqb->createNamedParameter($tagName)),
+                $sqb->expr()->eq('visibility', $sqb->createNamedParameter(1)),
+            ))->executeQuery()->fetchOne();
+    }
+
+    public function transformTagFilter(IQueryBuilder &$query, string $userId, string $tagName) {
+        $tagId = $this->getSystemTagId($query, $tagName);
+        if ($tagId === FALSE) {
+            $tagId = 0; // cannot abort here; that will show up everything in the response
+        }
+
+        $query->innerJoin('m', 'systemtag_object_mapping', 'stom', $query->expr()->andX(
+            $query->expr()->eq('stom.objecttype', $query->createNamedParameter("files")),
+            $query->expr()->eq('stom.objectid', 'm.fileid'),
+            $query->expr()->eq('stom.systemtagid', $query->createNamedParameter($tagId)),
+        ));
+    }
+
+    public function getTags(Folder $folder) {
+        $query = $this->connection->getQueryBuilder();
+
+        // SELECT visible tag name and count of photos
+        $count = $query->func()->count($query->createFunction('DISTINCT m.fileid'), 'count');
+        $query->select('st.name', $count)->from('systemtag', 'st')->where(
+            $query->expr()->eq('visibility', $query->createNamedParameter(1)),
+        );
+
+        // WHERE there are items with this tag
+        $query->innerJoin('st', 'systemtag_object_mapping', 'stom', $query->expr()->andX(
+            $query->expr()->eq('stom.systemtagid', 'st.id'),
+            $query->expr()->eq('stom.objecttype', $query->createNamedParameter("files")),
+        ));
+
+        // WHERE these items are memories indexed photos
+        $query->innerJoin('stom', 'memories', 'm', $query->expr()->eq('m.fileid', 'stom.objectid'));
+
+        // WHERE these photos are in the user's requested folder recursively
+        $query->innerJoin('m', 'filecache', 'f', $this->getFilecacheJoinQuery($query, $folder, true, false));
+
+        // GROUP by tag name
+        $query->groupBy('st.name');
+
+        // FETCH all tags
+        $tags = $query->executeQuery()->fetchAll();
+        return $tags;
+    }
+}