feat(admin): render mltextarea fields per locale

- MLField.vue is the one locale-switching wrapper; MLTextField,
  MLMarkdownField and the new MLTextareaField are shells around it
- isMLFieldType replaces the inline ML type-name checks in formState,
  FormView and RelationChildModal
- register mltextarea as a group-labelled control; rebuild dist

admin/src/components/form/fields/MLField.vue

@@ -0,0 +1,93 @@
+<script setup lang="ts">
+// The one locale-switching wrapper of the ML controls (mltext, mltextarea,
+// mlmarkdown). It owns the locale select, follows ML_LOCALE_CHANGE from every
+// other ML control, edits only the active locale and emits the whole map. The
+// inner control (TextField, TextareaField, MarkdownField) is passed in and
+// edits a plain string.
+import { computed, inject, onMounted, onUnmounted, ref, type Component } from 'vue'
+import type { FieldControlProps } from '../control'
+import { FORM_ENABLED_LOCALES } from '../formContext'
+import { ML_LOCALE_CHANGE, broadcastMLLocale, localeRecord } from '../mlLocale'
+
+interface MLFieldProps extends FieldControlProps {
+  /** The control that edits the active locale's text. */
+  inner: Component
+  /** The field type the inner control receives (text, textarea, markdown). */
+  innerType: string
+  /** The ML field type, shown on the root as data-ml-field. */
+  mlType: string
+}
+
+const props = defineProps<MLFieldProps>()
+const emit = defineEmits<{ 'update:modelValue': [value: Record<string, string>] }>()
+
+const values = computed(() => localeRecord(props.modelValue))
+const enabledLocales = inject(FORM_ENABLED_LOCALES, null)
+const locales = computed(() => {
+  const codes = enabledLocales?.value
+  return codes && codes.length > 0 ? [...codes] : []
+})
+const activeLocale = ref(locales.value[0] ?? 'en')
+
+const labelledBy = computed(() => `${props.controlId}-label`)
+const editorId = computed(() => `${props.controlId}-editor`)
+const activeText = computed(() => values.value[activeLocale.value] ?? '')
+// A stable field object for the inner control: it keeps size and attributes.
+const innerField = computed(() => ({ ...props.field, type: props.innerType }))
+
+function setLocale(locale: string) {
+  if (!locale) {
+    return
+  }
+  activeLocale.value = locale
+}
+
+function onLocaleInput(event: Event) {
+  const locale = (event.target as HTMLSelectElement).value
+  setLocale(locale)
+  broadcastMLLocale(locale)
+}
+
+function onText(text: string) {
+  emit('update:modelValue', { ...values.value, [activeLocale.value]: text })
+}
+
+function onBroadcast(event: Event) {
+  const locale = (event as CustomEvent<string>).detail
+  if (typeof locale === 'string' && locale !== '') {
+    setLocale(locale)
+  }
+}
+
+onMounted(() => {
+  window.addEventListener(ML_LOCALE_CHANGE, onBroadcast)
+})
+onUnmounted(() => {
+  window.removeEventListener(ML_LOCALE_CHANGE, onBroadcast)
+})
+</script>
+
+<template>
+  <div class="flex flex-col gap-1.5" role="group" :aria-labelledby="labelledBy" :data-ml-field="mlType">
+    <div class="flex flex-wrap items-center gap-2">
+      <select
+        data-ml-locale
+        class="rounded-control border border-border-strong bg-surface px-2 py-1 text-[13px]"
+        :value="activeLocale"
+        :aria-label="`Locale for ${field.label || field.name}`"
+        @change="onLocaleInput"
+      >
+        <option v-for="code in locales" :key="code" :value="code">{{ code }}</option>
+      </select>
+    </div>
+    <component
+      :is="inner"
+      :field="innerField"
+      :model-value="activeText"
+      :control-id="editorId"
+      :invalid="invalid"
+      :described-by="describedBy"
+      @update:model-value="onText"
+    />
+  </div>
+</template>

admin/src/components/form/fields/MLMarkdownField.vue

@@ -1,78 +1,19 @@
 <script setup lang="ts">
-import { computed, inject, onMounted, onUnmounted, ref } from 'vue'
+// The mlmarkdown control: MLField around MarkdownField.
 import type { FieldControlProps } from '../control'
+import MLField from './MLField.vue'
 import MarkdownField from './MarkdownField.vue'
-import { FORM_ENABLED_LOCALES } from '../formContext'
-import { ML_LOCALE_CHANGE, broadcastMLLocale, localeRecord } from '../mlLocale'
 
 const props = defineProps<FieldControlProps>()
 const emit = defineEmits<{ 'update:modelValue': [value: Record<string, string>] }>()
-
-const values = computed(() => localeRecord(props.modelValue))
-const enabledLocales = inject(FORM_ENABLED_LOCALES, null)
-const locales = computed(() => {
-  const codes = enabledLocales?.value
-  return codes && codes.length > 0 ? [...codes] : []
-})
-const activeLocale = ref(locales.value[0] ?? 'en')
-
-const labelledBy = computed(() => `${props.controlId}-label`)
-const editorId = computed(() => `${props.controlId}-editor`)
-const activeText = computed(() => values.value[activeLocale.value] ?? '')
-const markdownField = computed(() => ({ ...props.field, type: 'markdown' }))
-
-function setLocale(locale: string) {
-  if (!locale) {
-    return
-  }
-  activeLocale.value = locale
-}
-
-function onLocaleInput(event: Event) {
-  const locale = (event.target as HTMLSelectElement).value
-  setLocale(locale)
-  broadcastMLLocale(locale)
-}
-
-function onText(text: string) {
-  emit('update:modelValue', { ...values.value, [activeLocale.value]: text })
-}
-
-function onBroadcast(event: Event) {
-  const locale = (event as CustomEvent<string>).detail
-  if (typeof locale === 'string' && locale !== '') {
-    setLocale(locale)
-  }
-}
-
-onMounted(() => {
-  window.addEventListener(ML_LOCALE_CHANGE, onBroadcast)
-})
-onUnmounted(() => {
-  window.removeEventListener(ML_LOCALE_CHANGE, onBroadcast)
-})
 </script>
 
 <template>
-  <div class="flex flex-col gap-1.5" role="group" :aria-labelledby="labelledBy" data-ml-field="mlmarkdown">
-    <div class="flex flex-wrap items-center gap-2">
-      <select
-        data-ml-locale
-        class="rounded-control border border-border-strong bg-surface px-2 py-1 text-[13px]"
-        :value="activeLocale"
-        :aria-label="`Locale for ${field.label || field.name}`"
-        @change="onLocaleInput"
-      >
-        <option v-for="code in locales" :key="code" :value="code">{{ code }}</option>
-      </select>
-    </div>
-    <MarkdownField
-      :field="markdownField"
-      :model-value="activeText"
-      :control-id="editorId"
-      :invalid="invalid"
-      :described-by="describedBy"
-      @update:model-value="onText"
-    />
-  </div>
+  <MLField
+    v-bind="props"
+    :inner="MarkdownField"
+    inner-type="markdown"
+    ml-type="mlmarkdown"
+    @update:model-value="emit('update:modelValue', $event)"
+  />
 </template>

admin/src/components/form/fields/MLTextField.vue

@@ -1,77 +1,19 @@
 <script setup lang="ts">
-import { computed, inject, onMounted, onUnmounted, ref } from 'vue'
+// The mltext control: MLField around TextField.
 import type { FieldControlProps } from '../control'
+import MLField from './MLField.vue'
 import TextField from './TextField.vue'
-import { FORM_ENABLED_LOCALES } from '../formContext'
-import { ML_LOCALE_CHANGE, broadcastMLLocale, localeRecord } from '../mlLocale'
 
 const props = defineProps<FieldControlProps>()
 const emit = defineEmits<{ 'update:modelValue': [value: Record<string, string>] }>()
-
-const values = computed(() => localeRecord(props.modelValue))
-const enabledLocales = inject(FORM_ENABLED_LOCALES, null)
-const locales = computed(() => {
-  const codes = enabledLocales?.value
-  return codes && codes.length > 0 ? [...codes] : []
-})
-const activeLocale = ref(locales.value[0] ?? 'en')
-
-const labelledBy = computed(() => `${props.controlId}-label`)
-const editorId = computed(() => `${props.controlId}-editor`)
-const activeText = computed(() => values.value[activeLocale.value] ?? '')
-
-function setLocale(locale: string) {
-  if (!locale) {
-    return
-  }
-  activeLocale.value = locale
-}
-
-function onLocaleInput(event: Event) {
-  const locale = (event.target as HTMLSelectElement).value
-  setLocale(locale)
-  broadcastMLLocale(locale)
-}
-
-function onText(text: string) {
-  emit('update:modelValue', { ...values.value, [activeLocale.value]: text })
-}
-
-function onBroadcast(event: Event) {
-  const locale = (event as CustomEvent<string>).detail
-  if (typeof locale === 'string' && locale !== '') {
-    setLocale(locale)
-  }
-}
-
-onMounted(() => {
-  window.addEventListener(ML_LOCALE_CHANGE, onBroadcast)
-})
-onUnmounted(() => {
-  window.removeEventListener(ML_LOCALE_CHANGE, onBroadcast)
-})
 </script>
 
 <template>
-  <div class="flex flex-col gap-1.5" role="group" :aria-labelledby="labelledBy" data-ml-field="mltext">
-    <div class="flex flex-wrap items-center gap-2">
-      <select
-        data-ml-locale
-        class="rounded-control border border-border-strong bg-surface px-2 py-1 text-[13px]"
-        :value="activeLocale"
-        :aria-label="`Locale for ${field.label || field.name}`"
-        @change="onLocaleInput"
-      >
-        <option v-for="code in locales" :key="code" :value="code">{{ code }}</option>
-      </select>
-    </div>
-    <TextField
-      :field="{ ...field, type: 'text' }"
-      :model-value="activeText"
-      :control-id="editorId"
-      :invalid="invalid"
-      :described-by="describedBy"
-      @update:model-value="onText"
-    />
-  </div>
+  <MLField
+    v-bind="props"
+    :inner="TextField"
+    inner-type="text"
+    ml-type="mltext"
+    @update:model-value="emit('update:modelValue', $event)"
+  />
 </template>

admin/src/components/form/fields/MLTextareaField.vue

@@ -0,0 +1,19 @@
+<script setup lang="ts">
+// The mltextarea control: MLField around TextareaField.
+import type { FieldControlProps } from '../control'
+import MLField from './MLField.vue'
+import TextareaField from './TextareaField.vue'
+
+const props = defineProps<FieldControlProps>()
+const emit = defineEmits<{ 'update:modelValue': [value: Record<string, string>] }>()
+</script>
+
+<template>
+  <MLField
+    v-bind="props"
+    :inner="TextareaField"
+    inner-type="textarea"
+    ml-type="mltextarea"
+    @update:model-value="emit('update:modelValue', $event)"
+  />
+</template>

admin/src/components/form/formState.ts

@@ -2,10 +2,10 @@
 // filtering, the save payload, 422 detail mapping and focus.
 import type { AdminRecord, ErrorBody, FormField } from '../../api/types'
 import { permissionValues } from './control'
-import { localeRecord } from './mlLocale'
+import { isMLFieldType, localeRecord } from './mlLocale'
 import { isRegistered } from './registry'
 
-export { ML_LOCALE_CHANGE, broadcastMLLocale, localeRecord } from './mlLocale'
+export { ML_LOCALE_CHANGE, broadcastMLLocale, isMLFieldType, localeRecord } from './mlLocale'
 
 /** The screen a field is filtered for: the two form modes and the read-only preview (D-11). */
 export type FormMode = 'create' | 'update' | 'preview'
@@ -65,7 +65,7 @@ export function editablePayload(fields: FormField[], values: AdminRecord, mode:
       out[field.name] = permissionValues(field, value)
       continue
     }
-    if (field.type === 'mltext' || field.type === 'mlmarkdown') {
+    if (isMLFieldType(field.type)) {
       out[field.name] = localeRecord(value)
       continue
     }
@@ -111,10 +111,6 @@ export function changedLocales(previous: unknown, next: unknown): string[] {
  * whole field when no locale is given, one locale of an ML target otherwise. */
 export type PresetEdited = (target: string, locale?: string) => boolean
 
-function isMLType(type: string | undefined): boolean {
-  return type === 'mltext' || type === 'mlmarkdown'
-}
-
 /**
  * The preset targets of `source` (fields.yaml `preset`) to rewrite after the
  * source changed from `previous` to `next`: target name -> new value. Targets
@@ -140,7 +136,7 @@ export function presetUpdates(
   isEdited: PresetEdited,
 ): AdminRecord {
   const out: AdminRecord = {}
-  const sourceML = isMLType(fields.find((field) => field.name === source)?.type)
+  const sourceML = isMLFieldType(fields.find((field) => field.name === source)?.type)
   for (const field of fields) {
     const preset = field.preset
     if (!preset || preset.field !== source || (field.type !== 'text' && field.type !== 'mltext')) {
@@ -188,7 +184,7 @@ export function initialValues(fields: FormField[], enabledLocales: readonly stri
       out[field.name] = false
     } else if (field.type === 'relation' && field.multiple) {
       out[field.name] = []
-    } else if (field.type === 'mltext' || field.type === 'mlmarkdown') {
+    } else if (isMLFieldType(field.type)) {
       const seed: Record<string, string> = {}
       for (const code of enabledLocales) {
         seed[code] = ''

admin/src/components/form/mlLocale.ts

@@ -1,3 +1,11 @@
+/** The multilingual field types: their value is a locale -> text map. */
+export const ML_FIELD_TYPES: ReadonlySet<string> = new Set(['mltext', 'mltextarea', 'mlmarkdown'])
+
+/** Reports whether a field type holds a locale -> text map. */
+export function isMLFieldType(type: string | undefined): boolean {
+  return type !== undefined && ML_FIELD_TYPES.has(type)
+}
+
 /** Window event that keeps every ML control on one active locale. */
 export const ML_LOCALE_CHANGE = 'summer:ml-locale'
 

admin/src/components/form/registry.ts

@@ -14,6 +14,9 @@
 // server never sends back, so it is empty on load and after every save. The
 // permissioneditor control is a value field too: an object of permission code
 // to value, labelled as a group.
+// The ML controls (mltext, mltextarea, mlmarkdown) are thin shells over one
+// locale-switching wrapper, MLField, around the text, textarea and markdown
+// controls; each holds a locale -> text map, labelled as a group.
 import type { Component } from 'vue'
 import CheckboxField from './fields/CheckboxField.vue'
 import DatepickerField from './fields/DatepickerField.vue'
@@ -30,6 +33,7 @@ import TextField from './fields/TextField.vue'
 import TextareaField from './fields/TextareaField.vue'
 import MarkdownField from './fields/MarkdownField.vue'
 import MLTextField from './fields/MLTextField.vue'
+import MLTextareaField from './fields/MLTextareaField.vue'
 import MLMarkdownField from './fields/MLMarkdownField.vue'
 import UnsupportedField from './fields/UnsupportedField.vue'
 import WidgetField from './fields/WidgetField.vue'
@@ -65,6 +69,7 @@ const renderers = new Map<string, Component>([
   ['permissioneditor', PermissionEditorField],
   ['markdown', MarkdownField],
   ['mltext', MLTextField],
+  ['mltextarea', MLTextareaField],
   ['mlmarkdown', MLMarkdownField],
 ])
 
@@ -85,7 +90,7 @@ const valueless = new Set<string>([RELATION_MANAGER, 'widget', 'partial', 'fileu
  * Types whose control is a group rather than one focusable element: the
  * visible label is a span the group points at, not a label for an input.
  */
-const groupLabelledTypes = new Set<string>(['widget', 'partial', 'fileupload', 'permissioneditor', 'mltext', 'mlmarkdown'])
+const groupLabelledTypes = new Set<string>(['widget', 'partial', 'fileupload', 'permissioneditor', 'mltext', 'mltextarea', 'mlmarkdown'])
 
 export function rendererFor(type: string): Component {
   return renderers.get(type) ?? lazyRenderers.get(type)?.() ?? UnsupportedField

admin/src/components/relation/RelationChildModal.vue

@@ -25,6 +25,7 @@ import {
   fieldErrors,
   focusField,
   initialValues,
+  isMLFieldType,
   mergeMLValue,
   panelDomId,
   snapshot,
@@ -217,7 +218,7 @@ function adopt(record: AdminRecord, meta?: RecordMeta): void {
   for (const field of fields.value) {
     if (field.type === 'password') {
       next[field.name] = ''
-    } else if (field.type === 'mltext' || field.type === 'mlmarkdown') {
+    } else if (isMLFieldType(field.type)) {
       next[field.name] = mergeMLValue(record[field.name], locales)
     }
   }

admin/src/views/FormView.vue

@@ -24,6 +24,7 @@ import {
   fieldErrors,
   focusField,
   initialValues,
+  isMLFieldType,
   mergeMLValue,
   panelDomId,
   presetUpdates,
@@ -177,7 +178,7 @@ function adopt(record: RecordEnvelope | undefined): void {
     for (const field of fields.value) {
       if (field.type === 'password') {
         next[field.name] = ''
-      } else if (field.type === 'mltext' || field.type === 'mlmarkdown') {
+      } else if (isMLFieldType(field.type)) {
         next[field.name] = mergeMLValue(record.data[field.name], locales)
       }
     }
@@ -221,7 +222,7 @@ async function load(): Promise<void> {
 const edited = new Set<string>()
 // The locales of each ML field the administrator edited by hand.
 const editedLocales = new Map<string, Set<string>>()
-// The locale every ML control shows (MLTextField broadcasts the choice).
+// The locale every ML control shows (any ML control broadcasts the choice).
 const mlLocale = ref('en')
 
 function firstMLLocale(): string {
@@ -249,7 +250,7 @@ function update(name: string, value: unknown): void {
   const next = { ...values.value, [name]: value }
   edited.add(name)
   const type = fields.value.find((field) => field.name === name)?.type
-  if (type === 'mltext' || type === 'mlmarkdown') {
+  if (isMLFieldType(type)) {
     let locales = editedLocales.get(name)
     if (!locales) {
       locales = new Set<string>()