log: serve translated content when available; English fallback

Adds module-level _resolve_log_content(session, log_id, lang) helper
to app/routers/pages.py: looks up StrategicLogTranslation by (log_id,
lang) when lang != 'en'; falls back silently to the English original
when no translation row exists yet (the expected case for the first
hour after a new language activates, or when translation fails for a
specific log).

log_page / log_page_day pull cu.user.lang and thread it through
_log_page_context so the template renders the right variant.

Two tests cover both branches.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

app/routers/pages.py

@@ -11,7 +11,7 @@ from sqlalchemy.ext.asyncio import AsyncSession
 from app.auth import CurrentUser, maybe_current_user, require_auth, require_token
 from app.config import get_settings, load_groups
 from app.db import get_session
-from app.models import EmailSend, Referral, StrategicLog, User
+from app.models import EmailSend, Referral, StrategicLog, StrategicLogTranslation, User
 from app.services.access import is_paid_active, paid_status
 from app.services.referral_service import assign_code_if_missing
 from app.templates_env import templates
@@ -75,7 +75,29 @@ async def _resolve_log_date(session: AsyncSession, day: str | None) -> date:
     return datetime.now(timezone.utc).date()
 
 
-def _log_page_context(target: date, paid: bool) -> dict:
+async def _resolve_log_content(
+    session: AsyncSession, log_id: int, lang: str | None,
+) -> str:
+    """Return the strategic log content in the user's preferred language.
+
+    If ``lang`` is 'en'/None or no translation exists for the requested
+    language, returns the English original from StrategicLog.content.
+    A missing translation is the expected case for hours where
+    translation hasn't yet run; the fallback is silent.
+    """
+    if lang and lang != "en":
+        row = (await session.execute(
+            select(StrategicLogTranslation)
+            .where(StrategicLogTranslation.log_id == log_id)
+            .where(StrategicLogTranslation.lang == lang)
+        )).scalar_one_or_none()
+        if row is not None:
+            return row.content_md
+    log_row = await session.get(StrategicLog, log_id)
+    return log_row.content if log_row is not None else ""
+
+
+def _log_page_context(target: date, paid: bool, user_lang: str = "en") -> dict:
     s = get_settings()
     return {
         "selected_iso": target.isoformat(),
@@ -83,6 +105,7 @@ def _log_page_context(target: date, paid: bool) -> dict:
         "current_tone": s.CASSANDRA_TONE.upper(),
         "current_analysis": s.CASSANDRA_ANALYSIS.upper(),
         "paid": paid,
+        "user_lang": user_lang,
     }
 
 
@@ -93,8 +116,9 @@ async def log_page(
     cu: CurrentUser = Depends(require_auth),
 ):
     target = await _resolve_log_date(session, None)
+    user_lang = cu.user.lang if cu.user else "en"
     return templates.TemplateResponse(
-        request, "log.html", _log_page_context(target, is_paid_active(cu)),
+        request, "log.html", _log_page_context(target, is_paid_active(cu), user_lang),
     )
 
 
@@ -106,8 +130,9 @@ async def log_page_day(
     cu: CurrentUser = Depends(require_auth),
 ):
     target = await _resolve_log_date(session, day)
+    user_lang = cu.user.lang if cu.user else "en"
     return templates.TemplateResponse(
-        request, "log.html", _log_page_context(target, is_paid_active(cu)),
+        request, "log.html", _log_page_context(target, is_paid_active(cu), user_lang),
     )
 
 

tests/test_localization_integration.py

@@ -332,3 +332,66 @@ def test_digest_pick_variant_uses_user_lang():
     assert ed._pick_variant(table, tone="NOVICE", lang="de") == "novice en"
     # Missing tone → fallback to INTERMEDIATE/en (the safe default).
     assert ed._pick_variant(table, tone="UNKNOWN", lang="en") == "intermediate en"
+
+
+@pytest.mark.asyncio
+async def test_log_endpoint_serves_italian_when_user_is_italian(tmp_path):
+    """When a user with lang='it' opens /log, the served content is the
+    Italian translation, not the English original."""
+    from app.db import utcnow
+    from app.models import StrategicLog, StrategicLogTranslation, User
+
+    _, factory, setup = _build_session_factory(tmp_path)
+    await setup()
+
+    async with factory() as session:
+        session.add(User(id=10, email="it@x", tier="paid", lang="it"))
+        slog = StrategicLog(
+            generated_at=utcnow(), content="# Open\n\nDown 0.4%.",
+            model="test-model",
+            tone="INTERMEDIATE", analysis="NORMAL",
+        )
+        session.add(slog)
+        await session.commit()
+        session.add(StrategicLogTranslation(
+            log_id=slog.id, lang="it",
+            content_md="# Apertura\n\nIn calo 0,4%.",
+            generated_at=utcnow(), llm_model="m", llm_cost_usd=0.0,
+        ))
+        await session.commit()
+        log_id = slog.id
+
+    # Test the resolver directly.
+    from app.routers.pages import _resolve_log_content
+    async with factory() as session:
+        user = await session.get(User, 10)
+        content = await _resolve_log_content(session, log_id, user.lang)
+    assert "Apertura" in content
+    assert "Open" not in content
+
+
+@pytest.mark.asyncio
+async def test_log_endpoint_falls_back_to_english_when_no_translation(tmp_path):
+    """User lang='it' but no IT translation exists → English fallback."""
+    from app.db import utcnow
+    from app.models import StrategicLog, User
+
+    _, factory, setup = _build_session_factory(tmp_path)
+    await setup()
+
+    async with factory() as session:
+        session.add(User(id=11, email="it2@x", tier="paid", lang="it"))
+        slog = StrategicLog(
+            generated_at=utcnow(), content="# Open\n\nDown 0.4%.",
+            model="test-model",
+            tone="INTERMEDIATE", analysis="NORMAL",
+        )
+        session.add(slog)
+        await session.commit()
+        log_id = slog.id
+
+    from app.routers.pages import _resolve_log_content
+    async with factory() as session:
+        user = await session.get(User, 11)
+        content = await _resolve_log_content(session, log_id, user.lang)
+    assert "Open" in content