Add scoped postbox template previews

src/govoplan_postbox/backend/router.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+from collections.abc import Mapping
 from dataclasses import asdict
 from typing import Literal
 
@@ -60,6 +61,8 @@ from govoplan_postbox.backend.schemas import (
     PostboxTemplateCreateRequest,
     PostboxTemplateItem,
     PostboxTemplateListResponse,
+    PostboxTemplatePreviewRequest,
+    PostboxTemplatePreviewResponse,
     PostboxTemplatePublishRequest,
     PostboxTemplateReviseRequest,
 )
@@ -252,6 +255,10 @@ def _template_item(template) -> PostboxTemplateItem:
                 "function_type_id": revision.function_type_id,
                 "scope_kind": revision.scope_kind,
                 "scope_id": revision.scope_id,
+                "scope_structure_id": revision.scope_structure_id,
+                "scope_relation_type_ids": list(
+                    revision.scope_relation_type_ids or []
+                ),
                 "name_pattern": revision.name_pattern,
                 "address_pattern": revision.address_pattern,
                 "classification": revision.classification,
@@ -271,18 +278,33 @@ def _template_item(template) -> PostboxTemplateItem:
     )
 
 
-def _grouping_item(grouping, *, visible_ids: set[str]) -> PostboxGroupingItem:
+def _grouping_item(
+    grouping,
+    *,
+    visible_ids: set[str],
+    counts_by_postbox: Mapping[str, Mapping[str, int]] | None = None,
+) -> PostboxGroupingItem:
+    visible_source_ids = [
+        source.postbox_id
+        for source in grouping.sources
+        if source.postbox_id in visible_ids
+    ]
+    counts = counts_by_postbox or {}
     return PostboxGroupingItem(
         id=grouping.id,
         name=grouping.name,
         is_default=grouping.is_default,
         resource_revision=grouping.resource_revision,
         etag=grouping.strong_etag,
-        postbox_ids=[
-            source.postbox_id
-            for source in grouping.sources
-            if source.postbox_id in visible_ids
-        ],
+        postbox_ids=visible_source_ids,
+        total_count=sum(
+            int(counts.get(postbox_id, {}).get("total", 0))
+            for postbox_id in visible_source_ids
+        ),
+        unread_count=sum(
+            int(counts.get(postbox_id, {}).get("unread", 0))
+            for postbox_id in visible_source_ids
+        ),
         created_at=grouping.created_at,
         updated_at=grouping.updated_at,
     )
@@ -618,9 +640,19 @@ def api_list_postbox_groupings(
         tenant_id=principal.tenant_id,
         actor=actor,
     )
+    counts_by_postbox = get_service().message_counts_by_postbox(
+        session,
+        tenant_id=principal.tenant_id,
+        postbox_ids=tuple(visible_ids),
+        actor=actor,
+    )
     return PostboxGroupingListResponse(
         groupings=[
-            _grouping_item(grouping, visible_ids=visible_ids)
+            _grouping_item(
+                grouping,
+                visible_ids=visible_ids,
+                counts_by_postbox=counts_by_postbox,
+            )
             for grouping in groupings
         ]
     )
@@ -881,6 +913,27 @@ def api_create_postbox_template(
     return item
 
 
+@router.post(
+    "/admin/templates/preview",
+    response_model=PostboxTemplatePreviewResponse,
+)
+def api_preview_postbox_template(
+    payload: PostboxTemplatePreviewRequest,
+    session: Session = Depends(get_session),
+    principal: ApiPrincipal = Depends(get_api_principal),
+) -> PostboxTemplatePreviewResponse:
+    _require(principal, TEMPLATE_ADMIN_SCOPE)
+    try:
+        preview = get_service().preview_template_targets(
+            session,
+            tenant_id=principal.tenant_id,
+            **payload.model_dump(),
+        )
+    except PostboxError as exc:
+        raise _http_error(exc) from exc
+    return PostboxTemplatePreviewResponse.model_validate(preview)
+
+
 @router.post(
     "/admin/templates/{template_id}/revisions",
     response_model=PostboxTemplateItem,