Implement governed hybrid campaign delivery

src/govoplan_campaign/backend/integrations.py

@@ -28,6 +28,16 @@ from govoplan_core.core.postbox import (
     PostboxEvidenceProvider,
     PostboxTargetRef,
 )
+from govoplan_core.core.templates import (
+    CAPABILITY_TEMPLATE_CATALOG,
+    CAPABILITY_TEMPLATE_RENDERER,
+    TemplateCatalogProvider,
+    TemplateCompatibility,
+    TemplateRef,
+    TemplateRenderRequest,
+    TemplateRenderResult,
+    TemplateRendererProvider,
+)
 from govoplan_campaign.backend.runtime import capability
 
 
@@ -37,6 +47,8 @@ POSTBOX_CAPABILITY = CAPABILITY_POSTBOX_DELIVERY
 POSTBOX_DIRECTORY_CAPABILITY = CAPABILITY_POSTBOX_DIRECTORY
 POSTBOX_EVIDENCE_CAPABILITY = CAPABILITY_POSTBOX_EVIDENCE
 APPROVALS_CAPABILITY = CAPABILITY_APPROVAL_REQUESTS
+TEMPLATE_CATALOG_CAPABILITY = CAPABILITY_TEMPLATE_CATALOG
+TEMPLATE_RENDERER_CAPABILITY = CAPABILITY_TEMPLATE_RENDERER
 
 
 class OptionalModuleUnavailable(RuntimeError):
@@ -89,6 +101,10 @@ class ApprovalGateUnavailable(OptionalModuleUnavailable):
     pass
 
 
+class TemplateOutputUnavailable(OptionalModuleUnavailable):
+    pass
+
+
 class _PreparedCampaignSnapshot:
     def __init__(self, directory: Path, path: Path, raw_json: dict[str, Any]) -> None:
         self._directory = directory
@@ -493,6 +509,102 @@ class ApprovalCampaignIntegration:
         )
 
 
+class TemplatesCampaignIntegration:
+    def __init__(
+        self,
+        catalog_delegate: object | None = None,
+        renderer_delegate: object | None = None,
+    ) -> None:
+        self._catalog = (
+            catalog_delegate
+            if isinstance(catalog_delegate, TemplateCatalogProvider)
+            else None
+        )
+        self._renderer = (
+            renderer_delegate
+            if isinstance(renderer_delegate, TemplateRendererProvider)
+            else None
+        )
+
+    @property
+    def available(self) -> bool:
+        return self._catalog is not None and self._renderer is not None
+
+    def list_templates(
+        self,
+        session: object,
+        principal: object,
+        *,
+        query: str = "",
+        limit: int = 100,
+    ) -> tuple[TemplateRef, ...]:
+        if self._catalog is None:
+            return ()
+        return tuple(
+            self._catalog.list_templates(
+                session,
+                principal,
+                query=query,
+                usage="campaign_print",
+                limit=limit,
+            )
+        )
+
+    def check_compatibility(
+        self,
+        session: object,
+        principal: object,
+        *,
+        template_id: str,
+        revision: int | None,
+        output_format: str,
+        available_fields: dict[str, str] | tuple[str, ...],
+    ) -> TemplateCompatibility:
+        if self._catalog is None:
+            raise TemplateOutputUnavailable(
+                "Printable output is unavailable because Templates is not active."
+            )
+        return self._catalog.check_compatibility(
+            session,
+            principal,
+            template_id=template_id,
+            revision=revision,
+            usage="campaign_print",
+            output_format=output_format,
+            available_fields=available_fields,
+        )
+
+    def get_template(
+        self,
+        session: object,
+        principal: object,
+        *,
+        template_id: str,
+        revision: int,
+    ) -> TemplateRef | None:
+        if self._catalog is None:
+            return None
+        return self._catalog.get_template(
+            session,
+            principal,
+            template_id=template_id,
+            revision=revision,
+        )
+
+    def render(
+        self,
+        session: object,
+        principal: object,
+        *,
+        request: TemplateRenderRequest,
+    ) -> TemplateRenderResult:
+        if self._renderer is None:
+            raise TemplateOutputUnavailable(
+                "Printable output is unavailable because Templates is not active."
+            )
+        return self._renderer.render(session, principal, request=request)
+
+
 def files_integration() -> FilesCampaignIntegration:
     return FilesCampaignIntegration(capability(FILES_CAPABILITY))
 
@@ -511,3 +623,10 @@ def postbox_integration() -> PostboxCampaignIntegration:
 
 def approvals_integration() -> ApprovalCampaignIntegration:
     return ApprovalCampaignIntegration(capability(APPROVALS_CAPABILITY))
+
+
+def templates_integration() -> TemplatesCampaignIntegration:
+    return TemplatesCampaignIntegration(
+        capability(TEMPLATE_CATALOG_CAPABILITY),
+        capability(TEMPLATE_RENDERER_CAPABILITY),
+    )