<?php

declare(strict_types=1);

namespace App\FormBuilder\Bindings;

use App\Exceptions\FormBuilder\FormBindingApplicatorException;
use Throwable;

/**
 * Maps a Throwable to a failure_response_code string.
 *
 * Used by both ApplyBindingsOnFormSubmit::handle's catch block (D2) and
 * FormFailureRetryService::recordFailure (D2 update). Centralised so the
 * listener and the retry-service produce identical classifications and a
 * single behaviour change requires a single edit.
 *
 * Resolution order:
 * 1. If the Throwable is a FormBindingApplicatorException, return its reasonCode().
 *    Subclass dispatch handles SchemaConfig / Infra / DataIntegrity / Timeout
 *    (Timeout extends Infra so it inherits 'temporary_error').
 * 2. Otherwise, return 'unknown_error' — anything outside the hierarchy
 *    (database connection lost not surfaced as Infra, generic RuntimeException
 *    from a non-applicator code path, IdentityMatchInvariantViolation if it
 *    somehow leaks here) is unknown from the response-shape perspective.
 *
 * Per RFC-WS-6 §Q3 v1.3 addition 2.
 */
final class FormBindingExceptionClassifier
{
    public static function classify(Throwable $exception): string
    {
        if ($exception instanceof FormBindingApplicatorException) {
            return $exception->reasonCode();
        }

        return 'unknown_error';
    }
}