Implement multi-step registration process: Add step indicators, error handling, and payment processing for membership registration. Enhance form validation and user feedback with success and error messages. Refactor state management for improved clarity and maintainability.

server/api/helcim/update-billing.post.js

@@ -0,0 +1,71 @@
+// Update customer billing address
+const HELCIM_API_BASE = 'https://api.helcim.com/v2'
+
+export default defineEventHandler(async (event) => {
+  try {
+    const config = useRuntimeConfig(event)
+    const body = await readBody(event)
+    
+    // Validate required fields
+    if (!body.customerId || !body.billingAddress) {
+      throw createError({
+        statusCode: 400,
+        statusMessage: 'Customer ID and billing address are required'
+      })
+    }
+
+    const { billingAddress } = body
+    
+    // Validate billing address fields
+    if (!billingAddress.street || !billingAddress.city || !billingAddress.country || !billingAddress.postalCode) {
+      throw createError({
+        statusCode: 400,
+        statusMessage: 'Complete billing address is required'
+      })
+    }
+
+    const helcimToken = config.public.helcimToken || process.env.NUXT_PUBLIC_HELCIM_TOKEN
+    
+    // Update customer billing address in Helcim
+    const response = await fetch(`${HELCIM_API_BASE}/customers/${body.customerId}`, {
+      method: 'PATCH',
+      headers: {
+        'accept': 'application/json',
+        'content-type': 'application/json',
+        'api-token': helcimToken
+      },
+      body: JSON.stringify({
+        billingAddress: {
+          name: billingAddress.name,
+          street1: billingAddress.street,
+          city: billingAddress.city,
+          province: billingAddress.province || billingAddress.state,
+          country: billingAddress.country,
+          postalCode: billingAddress.postalCode
+        }
+      })
+    })
+    
+    if (!response.ok) {
+      const errorText = await response.text()
+      console.error('Billing address update failed:', response.status, errorText)
+      throw createError({
+        statusCode: response.status,
+        statusMessage: `Failed to update billing address: ${errorText}`
+      })
+    }
+    
+    const customerData = await response.json()
+
+    return {
+      success: true,
+      customer: customerData
+    }
+  } catch (error) {
+    console.error('Error updating billing address:', error)
+    throw createError({
+      statusCode: error.statusCode || 500,
+      statusMessage: error.message || 'Failed to update billing address'
+    })
+  }
+})