Add inline MailerLite section to form config

resources/dist/build/assets/addon-l0sNRNKZ.js

@@ -0,0 +1 @@
+

resources/dist/build/manifest.json

@@ -1,6 +1,6 @@
 {
   "resources/js/addon.js": {
-    "file": "assets/addon-e4Zwj-7O.js",
+    "file": "assets/addon-l0sNRNKZ.js",
     "name": "addon",
     "src": "resources/js/addon.js",
     "isEntry": true

resources/js/addon.js

@@ -1,5 +1,3 @@
-import Index from './pages/FormConfig/Index.vue';
-
-Statamic.booting(() => {
-    Statamic.$inertia.register('statamic-mailerlite::FormConfig/Index', Index);
-});
+// No custom Control Panel components. MailerLite configuration lives on the
+// native form configure page, injected via Form::appendConfigFields() in the
+// addon service provider.

src/Fieldtypes/MailerLiteFields.php

@@ -0,0 +1,100 @@
+<?php
+
+namespace Concept7\StatamicMailerLite\Fieldtypes;
+
+use MailerLite\MailerLite;
+use Statamic\CP\Column;
+use Statamic\Facades\Addon;
+use Statamic\Fieldtypes\Relationship;
+
+class MailerLiteFields extends Relationship
+{
+    protected $component = 'relationship';
+
+    protected $indexComponent = 'text';
+
+    protected $canCreate = false;
+
+    protected $canEdit = false;
+
+    protected $canSearch = false;
+
+    protected $statusIcons = false;
+
+    /** @var array<string, array<int, array{id: string, title: string}>> */
+    private static array $cache = [];
+
+    protected function toItemArray($id)
+    {
+        return collect($this->fields())->firstWhere('id', $id) ?? $this->invalidItemArray($id);
+    }
+
+    public function getIndexItems($request)
+    {
+        return collect($this->fields());
+    }
+
+    protected function getColumns()
+    {
+        return [
+            Column::make('title')->label(__('Name')),
+        ];
+    }
+
+    public function preProcessIndex($data)
+    {
+        if (! $data) {
+            return [];
+        }
+
+        return collect($data)->map(function ($id) {
+            $item = $this->toItemArray($id);
+
+            return $item['title'] ?? $id;
+        })->join(', ');
+    }
+
+    /**
+     * The selectable MailerLite subscriber fields, always including the built-in
+     * email attribute. Values are MailerLite field keys (the subscriber payload
+     * is keyed by key, not id); email maps to the SDK's top-level email attribute.
+     *
+     * @return array<int, array{id: string, title: string}>
+     */
+    private function fields(): array
+    {
+        $baseline = [
+            ['id' => 'email', 'title' => __('Email (built-in)')],
+        ];
+
+        $apiKey = Addon::get('concept7/statamic-mailerlite')->setting('api_key');
+
+        if (blank($apiKey)) {
+            return $baseline;
+        }
+
+        $cacheKey = hash('sha256', $apiKey);
+
+        if (isset(self::$cache[$cacheKey])) {
+            return self::$cache[$cacheKey];
+        }
+
+        $custom = rescue(function () use ($apiKey): array {
+            $response = (new MailerLite(['api_key' => $apiKey]))
+                ->fields
+                ->get([
+                    'limit' => 100,
+                    'sort' => 'name',
+                ]);
+
+            return collect($response['body']['data'] ?? [])
+                ->map(fn (array $field): array => [
+                    'id' => $field['key'],
+                    'title' => $field['name'],
+                ])
+                ->all();
+        }, [], report: false);
+
+        return self::$cache[$cacheKey] = [...$baseline, ...$custom];
+    }
+}