Update billing.py

Author: beacoder

app/routes/billing.py

@@ -1,12 +1,15 @@
-"""Billing routes: usage ledger summaries (tokens per user)."""
+"""Billing routes: usage ledger summaries (tokens per user).
+
+HTTP wiring only; the aggregation lives in ``controllers.usage``.
+"""
 
 from __future__ import annotations
 
 from fastapi import APIRouter, Depends
-from sqlalchemy import func, select
 from sqlalchemy.orm import Session
 
-from ..models import Conversation, Run, UsageEvent, User
+from ..controllers import usage
+from ..models import User
 from ..models.db import get_db
 from ..routes.auth import authenticate_user
 from ..validation.schemas import UsageSummary
@@ -18,35 +21,11 @@
 def usage_summary(
     user: User = Depends(authenticate_user), db: Session = Depends(get_db)
 ) -> UsageSummary:
-    rows = db.execute(
-        select(
-            UsageEvent.conversation_id,
-            func.sum(UsageEvent.input_tokens),
-            func.sum(UsageEvent.output_tokens),
-            func.sum(UsageEvent.rounds),
-        )
-        .where(UsageEvent.user_id == user.id)
-        .group_by(UsageEvent.conversation_id)
-    ).all()
-    by_conversation: dict[str, int] = {}
-    input_total = output_total = rounds_total = 0
-    for conversation_id, inp, out, rounds in rows:
-        inp_i, out_i, rounds_i = int(inp or 0), int(out or 0), int(rounds or 0)
-        input_total += inp_i
-        output_total += out_i
-        rounds_total += rounds_i
-        by_conversation[conversation_id] = inp_i + out_i
-    run_count = (
-        db.query(func.count(Run.id))
-        .join(Conversation, Run.conversation_id == Conversation.id)
-        .filter(Conversation.user_id == user.id)
-        .scalar()
-        or 0
-    )
+    totals = usage.summary(db, user)
     return UsageSummary(
-        input_tokens=input_total,
-        output_tokens=output_total,
-        rounds=rounds_total,
-        runs=int(run_count),
-        by_conversation=by_conversation,
+        input_tokens=totals.input_tokens,
+        output_tokens=totals.output_tokens,
+        rounds=totals.rounds,
+        runs=totals.runs,
+        by_conversation=totals.by_conversation,
     )