<?php

namespace App\Polls;

/**
 * Picks a label from a per-locale array: {"en": "...", "nl": "..."}.
 */
class Localized
{
    /**
     * The label in the given (or current) locale, falling back to the app fallback
     * locale and then to the first label that is filled in.
     */
    public static function pick(?array $labels, ?string $locale = null): string
    {
        $labels = array_filter($labels ?? [], fn ($label) => is_string($label) && trim($label) !== '');
        $locale = $locale ?? app()->getLocale();

        return $labels[$locale]
            ?? $labels[config('app.fallback_locale')]
            ?? (string) reset($labels);
    }

    /**
     * Validation rule: at least one locale has a label.
     */
    public static function filledRule(): \Closure
    {
        return function (string $attribute, $value, \Closure $fail) {
            if (!is_array($value) || self::pick($value) === '') {
                $fail(__('Fill in at least one language.'));
            }
        };
    }
}