class ApiController extends Controller
{

    public function sendRequest(Request $request){
        $rules = [
            'username' => 'required',
            'password' => 'required',
            //other rules
        ];

        // Initialize response array
        $response['success'] = false;

        // Validate the input
        $validator = Validator::make($request->all(), $rules);

        if ($validator->fails())
        {
            $response['errors'] = $validator->getMessageBag()->toArray();
            goto send_response;
        }

        $username = $request->input('username');
        $password = $request->input('password');

        $user = UserAuth::where('username', $username)->first();

        // Check if user exists
        if (null === $user){
            $response['errors']['username'] = 'Invalid Username';
            goto send_response;
        }

        // Check if password matches
        if (!Hash::check($password, $user->password)){
            $response['errors']['username'] = 'Invalid Password';
            goto send_response;
        }

        // other code here, at the end set $response['success'] to true

        send_response:
        return response()->json($response);

    }
}