<?php

declare(strict_types=1);

namespace Esun\MultiLocaleTranslation\Model;

use Magento\Framework\App\Config\ScopeConfigInterface;
use Magento\Store\Model\ScopeInterface;

class LocaleResolver
{
    private const LOCALE_PATH = 'general/locale/code';
    private const DEFAULT_SOURCE_LANGUAGE_PATH =
        'esun_multilocale_translation/general/default_source_language';

    private const GOOGLE_LANGUAGE_MAP = [
        'zh_CN' => 'zh-CN',
        'zh_Hans_CN' => 'zh-CN',
        'zh_TW' => 'zh-TW',
        'zh_Hant_TW' => 'zh-TW',
        'nb_NO' => 'no',
    ];

    private const DEEPL_TARGET_LANGUAGE_MAP = [
        'en_US' => 'EN-US',
        'en_GB' => 'EN-GB',
        'en_AU' => 'EN-GB',
        'pt_BR' => 'PT-BR',
        'pt_PT' => 'PT-PT',
        'zh_CN' => 'ZH-HANS',
        'zh_Hans_CN' => 'ZH-HANS',
        'zh_TW' => 'ZH-HANT',
        'zh_Hant_TW' => 'ZH-HANT',
    ];

    public function __construct(private readonly ScopeConfigInterface $scopeConfig)
    {
    }

    public function getLanguageCode(int $storeId, string $provider, bool $target): string
    {
        if ($storeId <= 0) {
            $locale = (string)$this->scopeConfig->getValue(self::DEFAULT_SOURCE_LANGUAGE_PATH);
        } else {
            $locale = (string)$this->scopeConfig->getValue(
                self::LOCALE_PATH,
                ScopeInterface::SCOPE_STORE,
                $storeId
            );
        }

        if ($locale === '') {
            throw new \RuntimeException((string)__('The Locale is not configured for this Store View.'));
        }

        if ($provider === 'deepl') {
            if ($target && isset(self::DEEPL_TARGET_LANGUAGE_MAP[$locale])) {
                return self::DEEPL_TARGET_LANGUAGE_MAP[$locale];
            }
            return strtoupper($this->getBaseLanguage($locale));
        }

        if (isset(self::GOOGLE_LANGUAGE_MAP[$locale])) {
            return self::GOOGLE_LANGUAGE_MAP[$locale];
        }

        return $this->getBaseLanguage($locale);
    }

    private function getBaseLanguage(string $locale): string
    {
        $parts = preg_split('/[_-]/', $locale);
        $language = strtolower((string)($parts[0] ?? ''));
        if ($language === '') {
            throw new \RuntimeException((string)__('Invalid Locale "%1".', $locale));
        }

        return $language;
    }
}