Caramel-CRM/app/Http/Controllers/SettingController.php

<?php

namespace App\Http\Controllers;

use App\Models\Setting;
use Illuminate\Http\Request;

class SettingController extends Controller
{
    public function index()
    {
        return response()->json(Setting::allKeyValue());
    }

    public function update(Request $request)
    {
        // Batch: {"settings": {"invoice_number_start": 2, "foo": "bar"}}
        if ($request->has('settings') && is_array($request->input('settings'))) {
            foreach ($request->input('settings') as $k => $v) {
                Setting::updateOrCreate(['key' => $k], ['value' => is_scalar($v) ? (string)$v : json_encode($v)]);
            }
            return response()->json(Setting::allKeyValue());
        }

        // Single: {"key":"invoice_number_start","value":2}
        $validated = $request->validate([
            'key' => 'required|string',
            'value' => 'nullable',
        ]);

        Setting::updateOrCreate(['key' => $validated['key']], ['value' => isset($validated['value']) && !is_scalar($validated['value']) ? json_encode($validated['value']) : (string)($validated['value'] ?? null)]);

        return response()->json(Setting::allKeyValue());
    }
}