refactor:centralize order status rules in shared package

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CONTRIBUTING.md

@@ -28,7 +28,6 @@ bun run dev:web
 Common checks:
 
 ```bash
-bun run check
 bun run test
 bun run build:web
 ```

apps/api/src/db/init-db.ts

@@ -90,7 +90,7 @@ export function initializeDatabase(sqlite: Database) {
       customer_id TEXT NOT NULL REFERENCES users(id),
       shipping_address_id TEXT NOT NULL REFERENCES addresses(id),
       status TEXT NOT NULL,
-      notes TEXT NOT NULL DEFAULT '',
+      notes TEXT,
       created_at TEXT NOT NULL,
       updated_at TEXT NOT NULL
     );
@@ -121,8 +121,7 @@ export function initializeDatabase(sqlite: Database) {
     );
   `);
 
-  // Existing local databases predate internal notes, so add the column in place.
   if (!columnExists(sqlite, "orders", "notes")) {
-    sqlite.exec(`ALTER TABLE orders ADD COLUMN notes TEXT NOT NULL DEFAULT ''`);
+    sqlite.exec("ALTER TABLE orders ADD COLUMN notes TEXT");
   }
 }

apps/api/src/db/schema/orders.ts

@@ -9,7 +9,7 @@ export const orders = sqliteTable("orders", {
   customerId: text("customer_id").notNull().references(() => users.id),
   shippingAddressId: text("shipping_address_id").notNull().references(() => addresses.id),
   status: text("status").notNull(),
-  notes: text("notes").notNull().default(""),
+  notes: text("notes"),
   createdAt: text("created_at").notNull(),
   updatedAt: text("updated_at").notNull()
 });

apps/api/src/orders/cancel-order.ts

@@ -1,5 +1,5 @@
+import { canCancelOrder, orderCancellationBlockedMessage } from "@orderops/shared/order-status";
 import type { DatabaseContext } from "../db/database";
-import { canCancelOrder } from "./order-status";
 import { appendAuditEvent, findOrderDetail, updateOrderStatus } from "./order-repository";
 
 export async function cancelOrder(
@@ -17,7 +17,7 @@ export async function cancelOrder(
   }
 
   if (!canCancelOrder(order.status)) {
-    return { statusCode: 400, message: "Order cannot be cancelled for this order status." } as const;
+    return { statusCode: 400, message: orderCancellationBlockedMessage } as const;
   }
 
   const updatedAt = new Date().toISOString();

apps/api/src/orders/order-quantity-assignment-3.test.ts

@@ -0,0 +1,91 @@
+import { afterEach, beforeEach, describe, expect, test } from "bun:test";
+import type { AppWithContext } from "../app";
+import { buildApp } from "../app";
+import { createUser } from "../users/user-repository";
+
+let app: AppWithContext;
+let employeeCookie = "";
+
+function firstHeader(value: string | string[] | undefined) {
+  return Array.isArray(value) ? value[0] : value ?? "";
+}
+
+async function login(username: string) {
+  const response = await app.inject({ method: "POST", url: "/api/login", payload: { username } });
+  return firstHeader(response.headers["set-cookie"]);
+}
+
+beforeEach(async () => {
+  app = await buildApp(":memory:");
+
+  await createUser(app.dbContext, {
+    username: "dev-employee",
+    name: "Dev Employee",
+    email: "dev.employee@example.com",
+    role: "employee"
+  });
+
+  employeeCookie = await login("dev-employee");
+});
+
+afterEach(async () => {
+  await app.close();
+});
+
+describe("assignment 3 quantity validation", () => {
+  test("allows quantity changes for pending orders", async () => {
+    const response = await app.inject({
+      method: "POST",
+      url: "/api/orders/order_1/items/item_1/quantity",
+      headers: { cookie: employeeCookie },
+      payload: { quantity: 5 }
+    });
+
+    expect(response.statusCode).toBe(200);
+    expect(response.json().items.find((item: { id: string }) => item.id === "item_1")?.quantity).toBe(5);
+  });
+
+  test("rejects quantity changes for processing orders", async () => {
+    const response = await app.inject({
+      method: "POST",
+      url: "/api/orders/order_2/items/item_3/quantity",
+      headers: { cookie: employeeCookie },
+      payload: { quantity: 2 }
+    });
+
+    expect(response.statusCode).toBe(400);
+  });
+
+  test("rejects quantity changes for shipped orders", async () => {
+    const response = await app.inject({
+      method: "POST",
+      url: "/api/orders/order_3/items/item_4/quantity",
+      headers: { cookie: employeeCookie },
+      payload: { quantity: 1 }
+    });
+
+    expect(response.statusCode).toBe(400);
+  });
+
+  test("rejects quantity outside the allowed range", async () => {
+    const response = await app.inject({
+      method: "POST",
+      url: "/api/orders/order_1/items/item_1/quantity",
+      headers: { cookie: employeeCookie },
+      payload: { quantity: 0 }
+    });
+
+    expect(response.statusCode).toBe(400);
+  });
+
+  test("rejects quantity above effective inventory", async () => {
+    const response = await app.inject({
+      method: "POST",
+      url: "/api/orders/order_1/items/item_1/quantity",
+      headers: { cookie: employeeCookie },
+      payload: { quantity: 9 }
+    });
+
+    expect(response.statusCode).toBe(400);
+  });
+});

apps/api/src/orders/order-repository.ts

@@ -98,14 +98,14 @@ export async function findOrderDetail(context: DatabaseContext, orderId: string)
     status: header.order.status as OrderDetail["status"],
     createdAt: header.order.createdAt,
     updatedAt: header.order.updatedAt,
+    notes: header.order.notes,
     customer: {
       id: header.customer.id,
       name: header.customer.name,
       email: header.customer.email
     },
     shippingAddress: toAddress(header.address),
-    items: itemRows.map(toOrderItemDetail),
+    items: itemRows.map(toOrderItemDetail)
-    notes: header.order.notes
   } satisfies OrderDetail;
 }
 
@@ -117,13 +117,24 @@ export async function findOrderItemRecord(context: DatabaseContext, orderId: str
     .leftJoin(inventory, eq(orderItems.productId, inventory.productId))
     .where(and(eq(orderItems.id, itemId), eq(orderItems.orderId, orderId)));
 
-  return row ?? null;
+  if (!row) {
+    return null;
+  }
+
+  return {
+    ...row,
+    order: { ...row.order, status: row.order.status as OrderDetail["status"] }
+  };
 }
 
 export async function updateOrderItemQuantity(context: DatabaseContext, itemId: string, quantity: number) {
   await context.db.update(orderItems).set({ quantity }).where(eq(orderItems.id, itemId));
 }
 
+export async function updateOrderNotes(context: DatabaseContext, orderId: string, notes: string) {
+  await context.db.update(orders).set({ notes }).where(eq(orders.id, orderId));
+}
+
 export async function updateOrderTimestamp(context: DatabaseContext, orderId: string, updatedAt: string) {
   await context.db.update(orders).set({ updatedAt }).where(eq(orders.id, orderId));
 }
@@ -175,10 +186,6 @@ export async function appendAuditEvent(
   });
 }
 
-export async function updateOrderNotes(context: DatabaseContext, orderId: string, notes: string) {
-  await context.db.update(orders).set({ notes }).where(eq(orders.id, orderId));
-}
-
 async function findCustomerSummaryByOrderId(context: DatabaseContext, orderId: string) {
   const [row] = await context.db
     .select({ customer: users })

apps/api/src/orders/order-routes.ts

@@ -6,8 +6,7 @@ import { cancelOrder } from "./cancel-order";
 import { getOrder } from "./get-order";
 import { listAuditEvents } from "./list-audit-events";
 import { listOrders } from "./list-orders";
-import { changeOrderItemQuantity } from "./update-order-item";
+import { changeOrderItemQuantity, updateOrderNotes } from "./update-order-item";
-import { saveOrderNotes } from "./update-order-notes";
 import { changeShippingAddress } from "./update-shipping-address";
 
 interface OrderRouteOptions {
@@ -100,6 +99,31 @@ export const registerOrderRoutes: FastifyPluginAsync<OrderRouteOptions> = async
     return result.order;
   });
 
+  app.post<{ Params: IdParams; Body: NotesBody }>("/orders/:orderId/notes", {
+    schema: {
+      body: {
+        type: "object",
+        required: ["notes"],
+        properties: {
+          notes: { type: "string", maxLength: 1000 }
+        }
+      }
+    }
+  }, async (request, reply) => {
+    const currentUser = (request as AuthenticatedRequest).currentUser;
+    const result = await updateOrderNotes(options.db, {
+      orderId: request.params.orderId,
+      notes: request.body.notes,
+      actor: currentUser.username
+    });
+
+    if (result.statusCode !== 200) {
+      return reply.code(result.statusCode).send({ message: result.message });
+    }
+
+    return result.order;
+  });
+
   app.post<{ Params: IdParams; Body: Address }>("/orders/:orderId/shipping-address", {
     schema: {
       body: {
@@ -162,28 +186,4 @@ export const registerOrderRoutes: FastifyPluginAsync<OrderRouteOptions> = async
 
     return result.order;
   });
-
-  app.post<{ Params: IdParams; Body: NotesBody }>("/orders/:orderId/notes", {
-    schema: {
-      body: {
-        type: "object",
-        required: ["notes"],
-        properties: {
-          // Empty and length rules are measured on the trimmed notes in saveOrderNotes.
-          notes: { type: "string" }
-        }
-      }
-    }
-  }, async (request, reply) => {
-    const result = await saveOrderNotes(options.db, {
-      orderId: request.params.orderId,
-      notes: request.body.notes
-    });
-
-    if (result.statusCode !== 200) {
-      return reply.code(result.statusCode).send({ message: result.message });
-    }
-
-    return result.order;
-  });
 };

apps/api/src/orders/order-status-rules-assignment-4.test.ts

@@ -0,0 +1,108 @@
+import { afterEach, beforeEach, describe, expect, test } from "bun:test";
+import type { AppWithContext } from "../app";
+import { buildApp } from "../app";
+import { createUser } from "../users/user-repository";
+
+let app: AppWithContext;
+let employeeCookie = "";
+
+function firstHeader(value: string | string[] | undefined) {
+  return Array.isArray(value) ? value[0] : value ?? "";
+}
+
+async function login(username: string) {
+  const response = await app.inject({ method: "POST", url: "/api/login", payload: { username } });
+  return firstHeader(response.headers["set-cookie"]);
+}
+
+beforeEach(async () => {
+  app = await buildApp(":memory:");
+
+  await createUser(app.dbContext, {
+    username: "dev-employee",
+    name: "Dev Employee",
+    email: "dev.employee@example.com",
+    role: "employee"
+  });
+
+  employeeCookie = await login("dev-employee");
+});
+
+afterEach(async () => {
+  await app.close();
+});
+
+describe("assignment 4 order lifecycle rules", () => {
+  test("keeps quantity editing blocked for processing orders", async () => {
+    const response = await app.inject({
+      method: "POST",
+      url: "/api/orders/order_2/items/item_3/quantity",
+      headers: { cookie: employeeCookie },
+      payload: { quantity: 2 }
+    });
+
+    expect(response.statusCode).toBe(400);
+  });
+
+  test("allows address editing for processing orders", async () => {
+    const response = await app.inject({
+      method: "POST",
+      url: "/api/orders/order_2/shipping-address",
+      headers: { cookie: employeeCookie },
+      payload: {
+        fullName: "Jane Doe",
+        line1: "50 New Street",
+        line2: null,
+        city: "Oakland",
+        state: "CA",
+        postalCode: "94607",
+        country: "US"
+      }
+    });
+
+    expect(response.statusCode).toBe(200);
+    expect(response.json().shippingAddress.city).toBe("Oakland");
+  });
+
+  test("allows cancellation for processing orders", async () => {
+    const response = await app.inject({
+      method: "POST",
+      url: "/api/orders/order_2/cancel",
+      headers: { cookie: employeeCookie },
+      payload: { reason: "Customer request" }
+    });
+
+    expect(response.statusCode).toBe(200);
+    expect(response.json().status).toBe("cancelled");
+  });
+
+  test("blocks address editing for shipped orders", async () => {
+    const response = await app.inject({
+      method: "POST",
+      url: "/api/orders/order_3/shipping-address",
+      headers: { cookie: employeeCookie },
+      payload: {
+        fullName: "John Smith",
+        line1: "77 Final Mile Road",
+        line2: null,
+        city: "Denver",
+        state: "CO",
+        postalCode: "80202",
+        country: "US"
+      }
+    });
+
+    expect(response.statusCode).toBe(400);
+  });
+
+  test("blocks cancellation for shipped orders", async () => {
+    const response = await app.inject({
+      method: "POST",
+      url: "/api/orders/order_3/cancel",
+      headers: { cookie: employeeCookie },
+      payload: { reason: "Late request" }
+    });
+
+    expect(response.statusCode).toBe(400);
+  });
+});

apps/api/src/orders/order-status.ts

@@ -1,13 +0,0 @@
-import type { OrderStatus } from "@orderops/shared/order-status";
-
-export function canEditOrderItems(status: OrderStatus) {
-  return status === "pending" || status === "processing";
-}
-
-export function canEditShippingAddress(status: OrderStatus) {
-  return status === "pending" || status === "processing";
-}
-
-export function canCancelOrder(status: OrderStatus) {
-  return status === "pending" || status === "processing";
-}

apps/api/src/orders/update-order-item.ts

@@ -1,6 +1,6 @@
+import { canEditOrderItems, orderItemsLockedMessage } from "@orderops/shared/order-status";
 import type { DatabaseContext } from "../db/database";
-import { canEditOrderItems } from "./order-status";
+import { appendAuditEvent, findOrderDetail, findOrderItemRecord, updateOrderItemQuantity, updateOrderNotes as saveOrderNotes, updateOrderTimestamp } from "./order-repository";
-import { appendAuditEvent, findOrderDetail, findOrderItemRecord, updateOrderItemQuantity, updateOrderTimestamp } from "./order-repository";
 
 export async function changeOrderItemQuantity(
   context: DatabaseContext,
@@ -17,8 +17,8 @@ export async function changeOrderItemQuantity(
     return { statusCode: 404, message: "Order item not found." } as const;
   }
 
-  if (!canEditOrderItems(row.order.status as never)) {
+  if (!canEditOrderItems(row.order.status)) {
-    return { statusCode: 400, message: "Order items cannot be changed for this order status." } as const;
+    return { statusCode: 400, message: orderItemsLockedMessage } as const;
   }
 
   if (input.quantity < 1 || input.quantity > 10) {
@@ -47,3 +47,44 @@ export async function changeOrderItemQuantity(
     order: await findOrderDetail(context, input.orderId)
   } as const;
 }
+
+export async function updateOrderNotes(
+  context: DatabaseContext,
+  input: {
+    orderId: string;
+    notes: string;
+    actor: string;
+  }
+) {
+  const order = await findOrderDetail(context, input.orderId);
+
+  if (!order) {
+    return { statusCode: 404, message: "Order not found." } as const;
+  }
+
+  const notes = input.notes.trim();
+
+  if (!notes) {
+    return { statusCode: 400, message: "Notes cannot be empty." } as const;
+  }
+
+  if (notes.length > 1000) {
+    return { statusCode: 400, message: "Notes must be 1000 characters or fewer." } as const;
+  }
+
+  const updatedAt = new Date().toISOString();
+  await saveOrderNotes(context, input.orderId, notes);
+  await updateOrderTimestamp(context, input.orderId, updatedAt);
+  await appendAuditEvent(context, {
+    orderId: input.orderId,
+    actor: input.actor,
+    type: "order.notes_updated",
+    message: "Updated internal order notes.",
+    createdAt: updatedAt
+  });
+
+  return {
+    statusCode: 200,
+    order: await findOrderDetail(context, input.orderId)
+  } as const;
+}

apps/api/src/orders/update-order-notes.ts

@@ -1,38 +0,0 @@
-import { orderNotesMaxLength } from "@orderops/shared";
-import type { DatabaseContext } from "../db/database";
-import { findOrderDetail, updateOrderNotes, updateOrderTimestamp } from "./order-repository";
-
-// Notes are allowed for every order status: follow-up work often happens
-// after an order has shipped, been cancelled, or been refunded.
-export async function saveOrderNotes(
-  context: DatabaseContext,
-  input: {
-    orderId: string;
-    notes: string;
-  }
-) {
-  const order = await findOrderDetail(context, input.orderId);
-
-  if (!order) {
-    return { statusCode: 404, message: "Order not found." } as const;
-  }
-
-  const notes = input.notes.trim();
-
-  if (!notes) {
-    return { statusCode: 400, message: "Notes cannot be empty." } as const;
-  }
-
-  if (notes.length > orderNotesMaxLength) {
-    return { statusCode: 400, message: `Notes must be ${orderNotesMaxLength} characters or fewer.` } as const;
-  }
-
-  const updatedAt = new Date().toISOString();
-  await updateOrderNotes(context, input.orderId, notes);
-  await updateOrderTimestamp(context, input.orderId, updatedAt);
-
-  return {
-    statusCode: 200,
-    order: await findOrderDetail(context, input.orderId)
-  } as const;
-}

apps/api/src/orders/update-shipping-address.ts

@@ -1,6 +1,6 @@
 import type { Address } from "@orderops/shared/address";
+import { canEditShippingAddress, shippingAddressLockedMessage } from "@orderops/shared/order-status";
 import type { DatabaseContext } from "../db/database";
-import { canEditShippingAddress } from "./order-status";
 import { appendAuditEvent, findOrderDetail, updateOrderAddress, updateOrderTimestamp } from "./order-repository";
 
 export async function changeShippingAddress(
@@ -18,7 +18,7 @@ export async function changeShippingAddress(
   }
 
   if (!canEditShippingAddress(order.status)) {
-    return { statusCode: 400, message: "Shipping address cannot be changed for this order status." } as const;
+    return { statusCode: 400, message: shippingAddressLockedMessage } as const;
   }
 
   const updatedAt = new Date().toISOString();

apps/web/src/orders/order-api.ts

@@ -21,6 +21,13 @@ export function updateOrderItemQuantity(orderId: string, itemId: string, quantit
   });
 }
 
+export function updateOrderNotes(orderId: string, notes: string) {
+  return apiRequest<OrderDetail>(`/api/orders/${orderId}/notes`, {
+    method: "POST",
+    body: JSON.stringify({ notes })
+  });
+}
+
 export function updateShippingAddress(orderId: string, address: Address) {
   return apiRequest<OrderDetail>(`/api/orders/${orderId}/shipping-address`, {
     method: "POST",
@@ -34,10 +41,3 @@ export function cancelOrder(orderId: string, reason?: string) {
     body: JSON.stringify({ reason })
   });
 }
-
-export function saveOrderNotes(orderId: string, notes: string) {
-  return apiRequest<OrderDetail>(`/api/orders/${orderId}/notes`, {
-    method: "POST",
-    body: JSON.stringify({ notes })
-  });
-}

apps/web/src/orders/order-detail-page.tsx

@@ -1,7 +1,7 @@
 import type { Address, AuditEvent, OrderDetail } from "@orderops/shared";
 import { AuditTimeline } from "./audit-timeline";
 import { OrderItemsPanel } from "./order-items-panel";
-import { OrderNotesPanel } from "./order-notes-panel";
+import { OrderNotes } from "./order-notes";
 import { OrderSummaryPanel } from "./order-summary";
 import { ShippingAddressForm } from "./shipping-address-form";
 
@@ -32,7 +32,7 @@ export function OrderDetailPage({
       </div>
       <OrderItemsPanel order={order} onUpdateQuantity={onUpdateQuantity} />
       <ShippingAddressForm order={order} onSave={onSaveAddress} />
-      <OrderNotesPanel notes={order.notes} onSaveNotes={onSaveNotes} />
+      <OrderNotes order={order} onSave={onSaveNotes} />
       <AuditTimeline events={auditEvents} />
     </div>
   );

apps/web/src/orders/order-notes-panel.tsx

@@ -1,56 +0,0 @@
-import { useEffect, useState } from "react";
-
-interface OrderNotesPanelProps {
-  notes: string;
-  onSaveNotes: (notes: string) => Promise<void>;
-}
-
-export function OrderNotesPanel({ notes, onSaveNotes }: OrderNotesPanelProps) {
-  const [draft, setDraft] = useState(notes);
-  const [isSaving, setIsSaving] = useState(false);
-  const canSubmit = draft.trim().length > 0 && draft !== notes && !isSaving;
-
-  // Show the stored notes again whenever the order is reloaded.
-  useEffect(() => {
-    setDraft(notes);
-  }, [notes]);
-
-  return (
-    <section className="rounded-xl border border-slate-200 bg-white p-4 shadow-sm">
-      <h3 className="text-sm font-semibold text-slate-700">Internal notes</h3>
-      <p className="mb-3 text-xs text-slate-500">Visible to OrderOps employees only.</p>
-      <form
-        className="space-y-2"
-        onSubmit={async (event) => {
-          event.preventDefault();
-
-          if (!canSubmit) {
-            return;
-          }
-
-          setIsSaving(true);
-          await onSaveNotes(draft);
-          setIsSaving(false);
-        }}
-      >
-        <label className="block text-sm text-slate-700">
-          <span className="mb-1 block">Notes</span>
-          <textarea
-            className="w-full rounded-lg border border-slate-300 px-3 py-2"
-            placeholder="Add context for teammates following up on this order"
-            rows={4}
-            value={draft}
-            onChange={(event) => setDraft(event.target.value)}
-          />
-        </label>
-        <button
-          className="rounded-md bg-slate-900 px-4 py-2 text-sm font-medium text-white disabled:opacity-50"
-          disabled={!canSubmit}
-          type="submit"
-        >
-          {isSaving ? "Saving notes..." : "Save notes"}
-        </button>
-      </form>
-    </section>
-  );
-}

apps/web/src/orders/order-notes.tsx

@@ -0,0 +1,37 @@
+import { useState } from "react";
+import type { OrderDetail } from "@orderops/shared";
+
+interface OrderNotesProps {
+  order: OrderDetail;
+  onSave: (notes: string) => Promise<void>;
+}
+
+export function OrderNotes({ order, onSave }: OrderNotesProps) {
+  const [notes, setNotes] = useState(order.notes ?? "");
+
+  return (
+    <section className="rounded-xl border border-slate-200 bg-white p-4 shadow-sm">
+      <h3 className="mb-3 text-sm font-semibold text-slate-700">Internal notes</h3>
+      <form
+        className="space-y-3"
+        onSubmit={async (event) => {
+          event.preventDefault();
+          await onSave(notes);
+        }}
+      >
+        <label className="block text-sm text-slate-700">
+          <span className="mb-1 block">Notes</span>
+          <textarea
+            className="w-full resize-none rounded-lg border border-slate-300 px-3 py-2"
+            rows={5}
+            value={notes}
+            onChange={(event) => setNotes(event.target.value)}
+          />
+        </label>
+        <button className="rounded-md bg-slate-900 px-4 py-2 text-sm font-medium text-white" type="submit">
+          Save notes
+        </button>
+      </form>
+    </section>
+  );
+}

apps/web/src/orders/order-page.tsx

@@ -1,8 +1,8 @@
 import { useEffect, useState } from "react";
-import type { Address, AuditEvent, OrderDetail } from "@orderops/shared";
+import { canEditOrderItems, orderItemsLockedMessage, type Address, type AuditEvent, type OrderDetail } from "@orderops/shared";
 import { Link, useParams } from "react-router-dom";
 import { Toast } from "../ui/toast";
-import { cancelOrder, getOrder, listAuditEvents, saveOrderNotes, updateOrderItemQuantity, updateShippingAddress } from "./order-api";
+import { cancelOrder, getOrder, listAuditEvents, updateOrderItemQuantity, updateOrderNotes, updateShippingAddress } from "./order-api";
 import { OrderDetailPage } from "./order-detail-page";
 
 interface ToastState {
@@ -72,6 +72,19 @@ export function OrderPage() {
     }
   }
 
+  async function handleUpdateQuantity(itemId: string, quantity: number) {
+    if (!order) {
+      return;
+    }
+
+    if (!canEditOrderItems(order.status)) {
+      setToast({ message: orderItemsLockedMessage, variant: "error" });
+      return;
+    }
+
+    await runAction(() => updateOrderItemQuantity(order.id, itemId, quantity), "Quantity saved.");
+  }
+
   return (
     <div className="space-y-4">
       <Link className="inline-flex text-sm font-medium text-blue-600 hover:text-blue-700" to="/orders">
@@ -84,9 +97,9 @@ export function OrderPage() {
         <OrderDetailPage
           order={order}
           auditEvents={auditEvents}
-          onUpdateQuantity={(itemId, quantity) => runAction(() => updateOrderItemQuantity(order.id, itemId, quantity), "Quantity saved.")}
+          onUpdateQuantity={handleUpdateQuantity}
           onSaveAddress={(address: Address) => runAction(() => updateShippingAddress(order.id, address), "Shipping address saved.")}
-          onSaveNotes={(notes: string) => runAction(() => saveOrderNotes(order.id, notes), "Internal notes saved.")}
+          onSaveNotes={(notes) => runAction(() => updateOrderNotes(order.id, notes), "Notes saved.")}
           onCancel={() => runAction(() => cancelOrder(order.id), "Order cancelled.")}
         />
       ) : null}

packages/shared/src/order-detail.ts

@@ -3,9 +3,6 @@ import type { CustomerSummary } from "./customer";
 import type { Money } from "./money";
 import type { OrderStatus } from "./order-status";
 
-// Shared so the API and the notes panel describe the same limit.
-export const orderNotesMaxLength = 1000;
-
 export interface OrderItemDetail {
   id: string;
   productId: string;
@@ -22,8 +19,8 @@ export interface OrderDetail {
   status: OrderStatus;
   createdAt: string;
   updatedAt: string;
+  notes: string | null;
   customer: CustomerSummary;
   shippingAddress: Address;
   items: OrderItemDetail[];
-  notes: string;
 }

packages/shared/src/order-status.ts

@@ -1,3 +1,23 @@
 export const orderStatuses = ["pending", "processing", "shipped", "cancelled", "refunded"] as const;
 
 export type OrderStatus = (typeof orderStatuses)[number];
+
+const orderItemsEditableStatuses: readonly OrderStatus[] = ["pending"];
+const shippingAddressEditableStatuses: readonly OrderStatus[] = ["pending", "processing"];
+const orderCancellableStatuses: readonly OrderStatus[] = ["pending", "processing"];
+
+export const orderItemsLockedMessage = "Order items cannot be changed for this order status.";
+export const shippingAddressLockedMessage = "Shipping address cannot be changed for this order status.";
+export const orderCancellationBlockedMessage = "Order cannot be cancelled for this order status.";
+
+export function canEditOrderItems(status: OrderStatus) {
+  return orderItemsEditableStatuses.includes(status);
+}
+
+export function canEditShippingAddress(status: OrderStatus) {
+  return shippingAddressEditableStatuses.includes(status);
+}
+
+export function canCancelOrder(status: OrderStatus) {
+  return orderCancellableStatuses.includes(status);
+}