Refactor NWC lud16 parsing to set initial value for lightning address

wallets/client/components/form/hooks.js

@@ -2,7 +2,6 @@ import { isTemplate, isWallet, protocolClientSchema, protocolFields, protocolFor
 import { createContext, useContext, useEffect, useMemo, useCallback, useState } from 'react'
 import { useWalletProtocolUpsert } from '@/wallets/client/hooks'
 import { MultiStepForm, useFormState, useStep } from '@/components/multi-step-form'
-import { parseNwcUrl } from '@/wallets/lib/validate'
 
 export const Step = {
   SEND: 'send',
@@ -83,9 +82,9 @@ function useProtocolFormState (protocol) {
 }
 
 export function useProtocolForm (protocol) {
+  const [globalFormState] = useFormState()
   const [formState, setFormState] = useProtocolFormState(protocol)
   const [complementaryFormState] = useProtocolFormState({ name: protocol.name, send: !protocol.send })
-  const [nwcSendFormState] = useProtocolFormState({ name: 'NWC', send: true })
   const wallet = useWallet()
   const lud16Domain = walletLud16Domain(wallet.name)
   const fields = protocolFields(protocol)
@@ -98,16 +97,13 @@ export function useProtocolForm (protocol) {
       value = complementaryFormState?.config?.[field.name]
     }
 
-    if (protocol.name === 'LN_ADDR' && field.name === 'address' && lud16Domain) {
-      // automatically set lightning addresses from NWC urls if lud16 parameter is present
-      if (nwcSendFormState?.config?.url) {
-        const { lud16 } = parseNwcUrl(nwcSendFormState.config.url)
-        if (lud16?.split('@')[1] === lud16Domain) value = lud16
-      }
-      // remove domain part since we will append it automatically if lud16Domain is set
-      if (lud16Domain && value) {
-        value = value.split('@')[0]
-      }
+    if (!value && field.populate && globalFormState) {
+      value = field.populate(wallet, globalFormState)
+    }
+
+    if (lud16Domain && value) {
+      // remove domain part since we will append it automatically on submit if lud16Domain is set
+      value = value.split('@')[0]
     }
 
     return {
@@ -120,6 +116,7 @@ export function useProtocolForm (protocol) {
   if (lud16Domain) {
     schema = schema.transform(({ address, ...rest }) => {
       return {
+        // append domain part to pass validation on submit
         address: address ? `${address}@${lud16Domain}` : '',
         ...rest
       }

wallets/client/components/form/index.js

@@ -100,6 +100,8 @@ function WalletProtocolForm () {
 
   // create a copy of values to avoid mutating the original
   const onSubmit = useCallback(async ({ ...values }) => {
+    // the schema transformation already does this to pass validation on submit
+    // so it would be better to use the transformed values instead of manually appending the domain part again here
     const lud16Domain = walletLud16Domain(wallet.name)
     if (values.address && lud16Domain) {
       values.address = `${values.address}@${lud16Domain}`
@@ -180,7 +182,7 @@ function WalletProtocolFormField ({ type, ...props }) {
   const [protocol] = useProtocol()
   const formik = useFormikContext()
 
-  function transform ({ validate, encrypt, editable, help, share, ...props }) {
+  function transform ({ validate, encrypt, editable, help, share, populate, ...props }) {
     const [upperHint, bottomHint] = Array.isArray(props.hint) ? props.hint : [null, props.hint]
 
     const parseHelpText = text => Array.isArray(text) ? text.join('\n\n') : text

wallets/lib/protocols/index.js

@@ -36,6 +36,14 @@ import clinkSuite from './clink'
  * @property {string} [hint] - hint text shown below field
  * @property {boolean} [share] - whether field can be used to prepopulate field of complementary send/receive protocol
  * @property {boolean} [editable] - whether the field is editable after it was saved
+ * @property {ProtocolFieldPopulate} [populate] - function to populate the field using values from other protocol forms
+ */
+
+/**
+ * @callback ProtocolFieldPopulate
+ * @param {Object} wallet - the wallet we are configuring
+ * @param {Object} formState - the current form state across all protocols
+ * @returns {string|null} - the value to populate the field with, or null if no value is available
  */
 
 /** @type {Protocol[]} */

wallets/lib/protocols/lnAddr.js

@@ -1,4 +1,5 @@
-import { externalLightningAddressValidator } from '@/wallets/lib/validate'
+import { externalLightningAddressValidator, parseNwcUrl } from '@/wallets/lib/validate'
+import { protocolFormId, walletLud16Domain } from '../util'
 
 // Lightning Address (LUD-16)
 // https://github.com/lnurl/luds/blob/luds/16.md
@@ -13,8 +14,30 @@ export default {
       label: 'address',
       type: 'text',
       required: true,
-      validate: externalLightningAddressValidator
+      validate: externalLightningAddressValidator,
+      populate: addressPopulate
     }
   ],
   relationName: 'walletRecvLightningAddress'
 }
+
+function addressPopulate (wallet, formState) {
+  const nwcFormId = protocolFormId({ name: 'NWC', send: true })
+  const nwcFormState = formState[nwcFormId]
+  if (!nwcFormState?.config?.url) {
+    return null
+  }
+
+  const { lud16: nwcLud16 } = parseNwcUrl(nwcFormState.config.url)
+  if (!nwcLud16) {
+    return null
+  }
+
+  const lud16Domain = walletLud16Domain(wallet.name)
+  const nwcLud16Domain = nwcLud16.split('@')[1]
+  if (lud16Domain && nwcLud16Domain !== lud16Domain) {
+    return null
+  }
+
+  return nwcLud16
+}