feat: add AirShelf core implementation

core/backend/apps/billing/views.py

@@ -0,0 +1,80 @@
+from decimal import Decimal, InvalidOperation
+
+from django.db import transaction
+from django.db.models import Sum
+from rest_framework import status
+from rest_framework.decorators import api_view, permission_classes
+from rest_framework.permissions import IsAuthenticated
+from rest_framework.response import Response
+
+from apps.common.api import get_current_team
+
+from .models import CreditAccount, CreditLedger
+from .serializers import CreditAccountSerializer, CreditLedgerSerializer
+
+
+@api_view(["GET"])
+@permission_classes([IsAuthenticated])
+def summary(request):
+    team = get_current_team(request.user)
+    account, _ = CreditAccount.objects.get_or_create(team=team)
+    charged = CreditLedger.objects.filter(team=team, ledger_type=CreditLedger.Type.CHARGE).aggregate(
+        total=Sum("amount")
+    )["total"] or 0
+    return Response(
+        {
+            "account": CreditAccountSerializer(account).data,
+            "charged_total": charged,
+        }
+    )
+
+
+@api_view(["GET"])
+@permission_classes([IsAuthenticated])
+def ledgers(request):
+    team = get_current_team(request.user)
+    queryset = CreditLedger.objects.filter(team=team).select_related("user", "project", "task").order_by("-created_at")
+    project_id = request.query_params.get("project")
+    user_id = request.query_params.get("user")
+    if project_id:
+        queryset = queryset.filter(project_id=project_id)
+    if user_id:
+        queryset = queryset.filter(user_id=user_id)
+    return Response(CreditLedgerSerializer(queryset[:100], many=True).data)
+
+
+@api_view(["POST"])
+@permission_classes([IsAuthenticated])
+def recharge(request):
+    team = get_current_team(request.user)
+    try:
+        amount = Decimal(str(request.data.get("amount", "0")))
+        bonus = Decimal(str(request.data.get("bonus", "0")))
+    except (InvalidOperation, TypeError):
+        return Response({"detail": "invalid amount"}, status=status.HTTP_400_BAD_REQUEST)
+    if amount <= 0:
+        return Response({"detail": "amount must be positive"}, status=status.HTTP_400_BAD_REQUEST)
+    if bonus < 0:
+        return Response({"detail": "bonus cannot be negative"}, status=status.HTTP_400_BAD_REQUEST)
+    channel = str(request.data.get("channel") or "manual")[:32]
+    credited = amount + bonus
+    with transaction.atomic():
+        account, _ = CreditAccount.objects.select_for_update().get_or_create(team=team)
+        account.balance += credited
+        account.save(update_fields=["balance", "updated_at"])
+        ledger = CreditLedger.objects.create(
+            team=team,
+            user=request.user,
+            ledger_type=CreditLedger.Type.RECHARGE,
+            amount=credited,
+            balance_after=account.balance,
+            reason="团队充值",
+            metadata={"channel": channel, "paid_amount": str(amount), "bonus": str(bonus)},
+        )
+    return Response(
+        {
+            "account": CreditAccountSerializer(account).data,
+            "ledger": CreditLedgerSerializer(ledger).data,
+        },
+        status=status.HTTP_201_CREATED,
+    )