initial_commit

umkm/order.py

@@ -0,0 +1,83 @@
+"""Mesin status order (FR-ORD-04, FR-ORD-09, FR-ORD-10, UC-07, UC-08)."""
+
+from datetime import timedelta
+from enum import Enum
+
+AUTO_COMPLETE_AFTER = timedelta(days=3)
+
+
+class OrderStatus(Enum):
+    PENDING_PAYMENT = "PENDING_PAYMENT"
+    PAID = "PAID"
+    SHIPPED = "SHIPPED"
+    COMPLETED = "COMPLETED"
+    CANCELLED = "CANCELLED"
+    EXPIRED = "EXPIRED"
+
+
+class InvalidTransitionError(Exception):
+    """Event tidak diizinkan pada status order saat ini."""
+
+
+class PermissionDeniedError(Exception):
+    """Pelaku tidak berhak memicu event ini."""
+
+
+S = OrderStatus
+
+# Tabel transisi: (status asal, event) -> status tujuan. Pasangan lain ditolak.
+TRANSITIONS = {
+    (S.PENDING_PAYMENT, "pay"): S.PAID,
+    (S.PENDING_PAYMENT, "cancel"): S.CANCELLED,
+    (S.PENDING_PAYMENT, "expire"): S.EXPIRED,
+    (S.PAID, "ship"): S.SHIPPED,
+    (S.SHIPPED, "complete"): S.COMPLETED,
+}
+
+
+class Order:
+    def __init__(self, order_id, buyer_id, seller_id):
+        self.order_id = order_id
+        self.buyer_id = buyer_id
+        self.seller_id = seller_id
+        self.status = S.PENDING_PAYMENT
+        self.shipped_at = None
+
+    def _fire(self, event):
+        target = TRANSITIONS.get((self.status, event))
+        if target is None:
+            raise InvalidTransitionError(f"{event} tidak valid pada status {self.status.value}")
+        self.status = target
+
+    def pay(self):
+        """Event payment.succeeded dari Payment Service."""
+        self._fire("pay")
+
+    def cancel(self, actor_id):
+        """Pembeli membatalkan order yang belum dibayar."""
+        if actor_id != self.buyer_id:
+            raise PermissionDeniedError("hanya pembeli yang dapat membatalkan")
+        self._fire("cancel")
+
+    def expire(self):
+        """Batas waktu pembayaran habis (dipicu sistem)."""
+        self._fire("expire")
+
+    def ship(self, actor_id, now):
+        """Seller pemilik toko menandai order terkirim."""
+        if actor_id != self.seller_id:
+            raise PermissionDeniedError("hanya seller pemilik toko yang dapat mengirim")
+        self._fire("ship")
+        self.shipped_at = now
+
+    def confirm_received(self, actor_id):
+        """Pembeli mengonfirmasi pesanan diterima. Seller tidak boleh."""
+        if actor_id != self.buyer_id:
+            raise PermissionDeniedError("hanya pembeli yang dapat mengonfirmasi")
+        self._fire("complete")
+
+    def auto_complete(self, now):
+        """Sistem menyelesaikan order 3 hari setelah SHIPPED tanpa konfirmasi."""
+        if self.status is S.SHIPPED and now - self.shipped_at < AUTO_COMPLETE_AFTER:
+            raise InvalidTransitionError("belum 3 hari sejak SHIPPED")
+        self._fire("complete")