feat(bulk): BulkTagService (common_tags/bulk_add/bulk_remove) + 3 image bulk-tag routes

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

backend/app/services/bulk_tag_service.py

@@ -0,0 +1,93 @@
+"""Bulk tag operations over a set of images (Core, set-based, atomic)."""
+
+from sqlalchemy import and_, func, select
+from sqlalchemy.dialects.postgresql import insert as pg_insert
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from ..models import Tag
+from ..models.tag import image_tag
+from ..models.tag_suggestion_rejection import TagSuggestionRejection
+
+
+class BulkTagService:
+    def __init__(self, session: AsyncSession):
+        self.session = session
+
+    async def common_tags(self, image_ids: list[int]) -> list[dict]:
+        """Tags present on EVERY image in image_ids."""
+        if not image_ids:
+            return []
+        n = len(set(image_ids))
+        stmt = (
+            select(Tag.id, Tag.name, Tag.kind)
+            .join(image_tag, image_tag.c.tag_id == Tag.id)
+            .where(image_tag.c.image_record_id.in_(image_ids))
+            .group_by(Tag.id, Tag.name, Tag.kind)
+            .having(
+                func.count(func.distinct(image_tag.c.image_record_id)) == n
+            )
+            .order_by(Tag.name.asc())
+        )
+        rows = (await self.session.execute(stmt)).all()
+        return [
+            {
+                "id": r.id,
+                "name": r.name,
+                "kind": r.kind.value if hasattr(r.kind, "value") else r.kind,
+            }
+            for r in rows
+        ]
+
+    async def bulk_add(
+        self, image_ids: list[int], tag_id: int, source: str = "manual"
+    ) -> int:
+        """Apply tag_id to every image. Idempotent per (image, tag).
+        Returns the number of links actually created."""
+        if not image_ids:
+            return 0
+        stmt = (
+            pg_insert(image_tag)
+            .values(
+                [
+                    {
+                        "image_record_id": iid,
+                        "tag_id": tag_id,
+                        "source": source,
+                    }
+                    for iid in set(image_ids)
+                ]
+            )
+            .on_conflict_do_nothing(
+                index_elements=["image_record_id", "tag_id"]
+            )
+        )
+        res = await self.session.execute(stmt)
+        return res.rowcount or 0
+
+    async def bulk_remove(self, image_ids: list[int], tag_id: int) -> int:
+        """Remove tag_id from every image, and record a per-image rejection
+        so the proactive allowlist sweep won't immediately re-add it
+        (mirrors single-image removal semantics). Returns links removed."""
+        if not image_ids:
+            return 0
+        res = await self.session.execute(
+            image_tag.delete().where(
+                and_(
+                    image_tag.c.tag_id == tag_id,
+                    image_tag.c.image_record_id.in_(image_ids),
+                )
+            )
+        )
+        await self.session.execute(
+            pg_insert(TagSuggestionRejection)
+            .values(
+                [
+                    {"image_record_id": iid, "tag_id": tag_id}
+                    for iid in set(image_ids)
+                ]
+            )
+            .on_conflict_do_nothing(
+                index_elements=["image_record_id", "tag_id"]
+            )
+        )
+        return res.rowcount or 0