refactor: Replace hardcoded billing data seeding with plugin-configurable collection overrides

- Remove `seedBillingData` function for sample data creation
- Update refunds, invoices, and payments collections to use pluginConfig for dynamic overrides
- Introduce utility functions like `extractSlug` for customizable collection slugs
- Streamline customer relation and data extractor logic across collections

src/plugin/config.ts

@@ -1,6 +1,11 @@
+import { CollectionConfig } from 'payload'
+import { FieldsOverride } from '@/plugin/utils'
 
 export const defaults = {
-  paymentsCollection: 'payments'
+  paymentsCollection: 'payments',
+  invoicesCollection: 'invoices',
+  refundsCollection: 'refunds',
+  customerRelationSlug: 'customer'
 }
 
 // Provider configurations
@@ -51,13 +56,12 @@ export interface BillingPluginConfig {
     dashboard?: boolean
   }
   collections?: {
-    customerRelation?: boolean | string // false to disable, string for custom collection slug
-    customers?: string
-    invoices?: string
-    payments?: string
-    refunds?: string
+    invoices?: string | (Partial<CollectionConfig> & {fields?: FieldsOverride})
+    payments?: string | (Partial<CollectionConfig> & {fields?: FieldsOverride})
+    refunds?: string | (Partial<CollectionConfig> & {fields?: FieldsOverride})
   }
   customerInfoExtractor?: CustomerInfoExtractor // Callback to extract customer info from relationship
+  customerRelationSlug?: string // Customer collection slug for relationship
   disabled?: boolean
   providers?: {
     mollie?: MollieConfig

src/plugin/index.ts

@@ -1,6 +1,6 @@
 import type { Config } from 'payload'
 import { createInvoicesCollection, createPaymentsCollection, createRefundsCollection } from '@/collections'
-import { BillingPluginConfig } from '@/plugin/config'
+import type { BillingPluginConfig } from '@/plugin/config'
 
 export const billingPlugin = (pluginConfig: BillingPluginConfig = {}) => (config: Config): Config => {
   if (pluginConfig.disabled) {
@@ -12,16 +12,10 @@ export const billingPlugin = (pluginConfig: BillingPluginConfig = {}) => (config
     config.collections = []
   }
 
-  const customerSlug = pluginConfig.collections?.customers || 'customers'
-
   config.collections.push(
-    createPaymentsCollection(pluginConfig.collections?.payments || 'payments'),
-    createInvoicesCollection(
-      pluginConfig.collections?.invoices || 'invoices',
-      pluginConfig.collections?.customerRelation !== false ? customerSlug : undefined,
-      pluginConfig.customerInfoExtractor
-    ),
-    createRefundsCollection(pluginConfig.collections?.refunds || 'refunds'),
+    createPaymentsCollection(pluginConfig),
+    createInvoicesCollection(pluginConfig),
+    createRefundsCollection(pluginConfig),
   )
 
   // Initialize endpoints

src/plugin/types.ts

@@ -1,7 +1,58 @@
-import { Customer, Refund } from '../../dev/payload-types'
 
 export type Id = string | number
 
+export interface Refund {
+  id: number;
+  /**
+   * The refund ID from the payment provider
+   */
+  providerId: string;
+  payment: number | Payment;
+  status: 'pending' | 'processing' | 'succeeded' | 'failed' | 'canceled';
+  /**
+   * Refund amount in cents
+   */
+  amount: number;
+  /**
+   * ISO 4217 currency code (e.g., USD, EUR)
+   */
+  currency: string;
+  /**
+   * Reason for the refund
+   */
+  reason?: ('duplicate' | 'fraudulent' | 'requested_by_customer' | 'other') | null;
+  /**
+   * Additional details about the refund
+   */
+  description?: string | null;
+  /**
+   * Additional refund metadata
+   */
+  metadata?:
+    | {
+    [k: string]: unknown;
+  }
+    | unknown[]
+    | string
+    | number
+    | boolean
+    | null;
+  /**
+   * Raw data from the payment provider
+   */
+  providerData?:
+    | {
+    [k: string]: unknown;
+  }
+    | unknown[]
+    | string
+    | number
+    | boolean
+    | null;
+  updatedAt: string;
+  createdAt: string;
+}
+
 export interface Payment {
   id: Id;
   provider: 'stripe' | 'mollie' | 'test';
@@ -22,7 +73,6 @@ export interface Payment {
    * Payment description
    */
   description?: string | null;
-  customer?: (Id | null) | Customer;
   invoice?: (Id | null) | Invoice;
   /**
    * Additional metadata for the payment
@@ -53,7 +103,7 @@ export interface Payment {
   createdAt: string;
 }
 
-export interface Invoice {
+export interface Invoice<TCustomer = unknown> {
   id: Id;
   /**
    * Invoice number (e.g., INV-001)
@@ -62,7 +112,7 @@ export interface Invoice {
   /**
    * Link to customer record (optional)
    */
-  customer?: (Id | null) | Customer;
+  customer?: (Id | null) | TCustomer;
   /**
    * Customer billing information (auto-populated from customer relationship)
    */
@@ -166,3 +216,4 @@ export interface Invoice {
   updatedAt: string;
   createdAt: string;
 }
+

src/plugin/utils.ts

@@ -0,0 +1,5 @@
+import type { CollectionConfig, Field } from 'payload'
+
+export type FieldsOverride = (args: { defaultFields: Field[] }) => Field[]
+
+export const extractSlug = (arg: string | Partial<CollectionConfig>) => typeof arg === 'string' ? arg : arg.slug!