<?php

declare(strict_types=1);

namespace Esun\Translation\Model\StoreView;

use Magento\Store\Model\StoreManagerInterface;

class LanguageGroupProvider
{
    public function __construct(
        private readonly StoreManagerInterface $storeManager
    ) {
    }

    /**
     * @return LanguageGroup[]
     */
    public function getGroups(): array
    {
        $groups = [];
        foreach ($this->storeManager->getStores(false) as $store) {
            if (!$store->isActive()) {
                continue;
            }

            $languageCode = $this->getLanguageCode((string)$store->getCode());
            if ($languageCode === '') {
                continue;
            }

            $groups[$languageCode]['label'] = $this->getLanguageLabel($languageCode);
            $groups[$languageCode]['store_ids'][] = (int)$store->getId();
            $groups[$languageCode]['store_codes'][] = (string)$store->getCode();
        }

        ksort($groups);

        return array_map(
            static fn (array $group): LanguageGroup => new LanguageGroup(
                $group['label'],
                $group['target_locale'],
                $group['store_ids'],
                $group['store_codes']
            ),
            array_map(
                static fn (array $group, string $languageCode): array => $group + ['target_locale' => $languageCode],
                $groups,
                array_keys($groups)
            )
        );
    }

    public function getGroup(string $label): ?LanguageGroup
    {
        foreach ($this->getGroups() as $group) {
            if ($group->getLabel() === $label || $group->getTargetLocale() === $label) {
                return $group;
            }
        }

        return null;
    }

    private function getLanguageCode(string $storeCode): string
    {
        if (!preg_match('/^([a-z]{2,3})(?:[_-]|$)/i', $storeCode, $matches)) {
            return '';
        }

        return strtolower($matches[1]);
    }

    private function getLanguageLabel(string $languageCode): string
    {
        if (class_exists(\Locale::class)) {
            $label = \Locale::getDisplayLanguage($languageCode, 'en');
            if (is_string($label) && $label !== '') {
                return ucfirst($label);
            }
        }

        return strtoupper($languageCode);
    }
}