From efcb276c45f2fd39306241dd84162973b36d8114 Mon Sep 17 00:00:00 2001
From: lifegpc <root@lifegpc.com>
Date: Thu, 14 Dec 2023 19:35:49 +0800
Subject: [PATCH] Add support for filtering files by gids in get_random_file()
 function

---
 db.ts                     | 17 +++++++++++++++--
 routes/api/file/random.ts | 35 ++++++++++++++++++++++++++++++++++-
 2 files changed, 49 insertions(+), 3 deletions(-)

diff --git a/db.ts b/db.ts
index 9412fb4..cfa71e9 100644
--- a/db.ts
+++ b/db.ts
@@ -1062,12 +1062,24 @@ export class EhDb {
     get_random_file(
         is_nsfw: boolean | null = null,
         is_ad: boolean | null = null,
+        gids: Set<number> | null = null,
     ) {
         const args = [];
         let join_sql = "";
+        const with_sql = [];
         const where_sql = [];
+        if (gids) {
+            const gids_sql = [];
+            for (const gid of gids) {
+                gids_sql.push("(?)");
+                args.push(gid);
+            }
+            with_sql.push(`WITH gids AS (VALUES ${gids_sql.join(",")})`);
+            join_sql += " INNER JOIN pmeta ON file.token = pmeta.token";
+            where_sql.push("pmeta.gid IN gids");
+        }
         if (is_nsfw !== null || is_ad !== null) {
-            join_sql = " LEFT JOIN filemeta ON file.token = filemeta.token";
+            join_sql += " LEFT JOIN filemeta ON file.token = filemeta.token";
             if (is_nsfw !== null) {
                 where_sql.push("IFNULL(filemeta.is_nsfw, 0) = ?");
                 args.push(is_nsfw);
@@ -1080,9 +1092,10 @@ export class EhDb {
         const wsql = where_sql.length
             ? ` WHERE ${where_sql.join(" AND ")}`
             : "";
+        const wisql = with_sql.length ? `${with_sql.join(" ")} ` : "";
         const s = this.convert_file(
             this.db.queryEntries<EhFileRaw>(
-                `SELECT file.* FROM file${join_sql}${wsql} ORDER BY RANDOM() LIMIT 1;`,
+                `${wisql}SELECT file.* FROM file${join_sql}${wsql} ORDER BY RANDOM() LIMIT 1;`,
                 args,
             ),
         );
diff --git a/routes/api/file/random.ts b/routes/api/file/random.ts
index 38869cb..08c6be1 100644
--- a/routes/api/file/random.ts
+++ b/routes/api/file/random.ts
@@ -10,7 +10,40 @@ export const handler: Handlers = {
         const is_nsfw = await parse_bool(u.searchParams.get("is_nsfw"), null);
         const is_ad = await parse_bool(u.searchParams.get("is_ad"), null);
         const thumb = await parse_bool(u.searchParams.get("thumb"), false);
-        const f = m.db.get_random_file(is_nsfw, is_ad);
+        const tgids = u.searchParams.get("gids");
+        let gids = tgids
+            ? new Set(
+                tgids.split(",").map((x) => parseInt(x)).filter((v) =>
+                    !isNaN(v)
+                ),
+            )
+            : null;
+        const meili_query = u.searchParams.get("meili_query");
+        const meili_filter = u.searchParams.get("meili_filter");
+        if (meili_query || meili_filter) {
+            if (!m.meilisearch) {
+                return new Response("Meilisearch is not enabled.", {
+                    status: 400,
+                });
+            }
+            try {
+                const index = await m.meilisearch.gmeta;
+                const re = await index.search(meili_query, {
+                    filter: meili_filter || undefined,
+                    hitsPerPage: 1000,
+                    attributesToRetrieve: ["gid"],
+                });
+                if (gids === null) {
+                    gids = new Set<number>();
+                }
+                re.hits.forEach((d) => {
+                    gids?.add(d.gid);
+                });
+            } catch (e) {
+                return new Response(e.message, { status: 400 });
+            }
+        }
+        const f = m.db.get_random_file(is_nsfw, is_ad, gids);
         if (!f) return new Response("File not found.", { status: 404 });
         const t = thumb ? "thumbnail" : "file";
         return Response.redirect(`${get_host(req)}/api/${t}/${f.id}`);