feat: Add embedded customer info to invoices with configurable relationship

- Add customerInfo and billingAddress fields to invoice collection
- Make customer relationship optional and configurable via plugin config
- Update TypeScript types to reflect new invoice structure
- Allow disabling customer relationship with customerRelation: false

🤖 Generated with [Claude Code](https://claude.ai/code)

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

src/collections/invoices.ts

@@ -10,7 +10,10 @@ import type {
   InvoiceItemData
 } from '../types/payload'
 
-export function createInvoicesCollection(slug: string = 'invoices'): CollectionConfig {
+export function createInvoicesCollection(
+  slug: string = 'invoices',
+  customerCollectionSlug?: string
+): CollectionConfig {
   return {
     slug,
     access: {
@@ -20,7 +23,7 @@ export function createInvoicesCollection(slug: string = 'invoices'): CollectionC
       update: ({ req: { user } }: AccessArgs) => !!user,
     },
     admin: {
-      defaultColumns: ['number', 'customer', 'status', 'amount', 'currency', 'dueDate'],
+      defaultColumns: ['number', 'customerInfo.name', 'status', 'amount', 'currency', 'dueDate'],
       group: 'Billing',
       useAsTitle: 'number',
     },
@@ -35,14 +38,116 @@ export function createInvoicesCollection(slug: string = 'invoices'): CollectionC
         required: true,
         unique: true,
       },
-      {
+      // Optional customer relationship
+      ...(customerCollectionSlug ? [{
         name: 'customer',
-        type: 'relationship',
+        type: 'relationship' as const,
         admin: {
-          position: 'sidebar',
+          position: 'sidebar' as const,
+          description: 'Link to customer record (optional)',
         },
-        relationTo: 'customers',
-        required: true,
+        relationTo: customerCollectionSlug as any,
+        required: false,
+      }] : []),
+      // Basic customer info fields (embedded)
+      {
+        name: 'customerInfo',
+        type: 'group',
+        admin: {
+          description: 'Customer billing information',
+        },
+        fields: [
+          {
+            name: 'name',
+            type: 'text',
+            admin: {
+              description: 'Customer name',
+            },
+            required: true,
+          },
+          {
+            name: 'email',
+            type: 'email',
+            admin: {
+              description: 'Customer email address',
+            },
+            required: true,
+          },
+          {
+            name: 'phone',
+            type: 'text',
+            admin: {
+              description: 'Customer phone number',
+            },
+          },
+          {
+            name: 'company',
+            type: 'text',
+            admin: {
+              description: 'Company name (optional)',
+            },
+          },
+          {
+            name: 'taxId',
+            type: 'text',
+            admin: {
+              description: 'Tax ID or VAT number',
+            },
+          },
+        ],
+      },
+      {
+        name: 'billingAddress',
+        type: 'group',
+        admin: {
+          description: 'Billing address',
+        },
+        fields: [
+          {
+            name: 'line1',
+            type: 'text',
+            admin: {
+              description: 'Address line 1',
+            },
+            required: true,
+          },
+          {
+            name: 'line2',
+            type: 'text',
+            admin: {
+              description: 'Address line 2',
+            },
+          },
+          {
+            name: 'city',
+            type: 'text',
+            required: true,
+          },
+          {
+            name: 'state',
+            type: 'text',
+            admin: {
+              description: 'State or province',
+            },
+          },
+          {
+            name: 'postalCode',
+            type: 'text',
+            admin: {
+              description: 'Postal or ZIP code',
+            },
+            required: true,
+          },
+          {
+            name: 'country',
+            type: 'text',
+            admin: {
+              description: 'Country code (e.g., US, GB)',
+            },
+            maxLength: 2,
+            required: true,
+          },
+        ],
       },
       {
         name: 'status',

src/collections/refunds.ts

@@ -1,6 +1,6 @@
 import type { CollectionConfig } from 'payload'
 
-import type { 
+import type {
   AccessArgs,
   CollectionAfterChangeHook,
   CollectionBeforeChangeHook,
@@ -116,21 +116,20 @@ export function createRefundsCollection(slug: string = 'refunds'): CollectionCon
         async ({ doc, operation, req }: CollectionAfterChangeHook<RefundDocument>) => {
           if (operation === 'create') {
             req.payload.logger.info(`Refund created: ${doc.id} for payment: ${doc.payment}`)
-            
+
             // Update the related payment's refund relationship
             try {
               const payment = await req.payload.findByID({
                 id: typeof doc.payment === 'string' ? doc.payment : doc.payment.id,
                 collection: 'payments',
               })
-              
+
               const refundIds = Array.isArray(payment.refunds) ? payment.refunds : []
-              
               await req.payload.update({
                 id: typeof doc.payment === 'string' ? doc.payment : doc.payment.id,
                 collection: 'payments',
                 data: {
-                  refunds: [...refundIds, doc.id],
+                  refunds: [...refundIds, doc.id as any],
                 },
               })
             } catch (error) {
@@ -146,7 +145,7 @@ export function createRefundsCollection(slug: string = 'refunds'): CollectionCon
             if (data.amount && !Number.isInteger(data.amount)) {
               throw new Error('Amount must be an integer (in cents)')
             }
-            
+
             // Validate currency format
             if (data.currency) {
               data.currency = data.currency.toUpperCase()
@@ -160,4 +159,4 @@ export function createRefundsCollection(slug: string = 'refunds'): CollectionCon
     },
     timestamps: true,
   }
-}
+}