// =========================================================================
// Reiss Multilingual Helpers
// =========================================================================
if (!function_exists('reiss_get_current_request_path')) {
    function reiss_get_current_request_path() {
        $current_request_uri = isset($_SERVER['REQUEST_URI']) ? wp_unslash($_SERVER['REQUEST_URI']) : '/';
        $current_path = strtok($current_request_uri, '?');

        if ($current_path === false || $current_path === '') {
            $current_path = '/';
        }

        $current_path = '/' . ltrim((string) $current_path, '/');
        $current_path = preg_replace('#/+#', '/', $current_path);

        return $current_path;
    }
}

if (!function_exists('reiss_get_default_lang')) {
    function reiss_get_default_lang() {
        return 'en';
    }
}

if (!function_exists('reiss_get_host')) {
    function reiss_get_host() {
        return home_url('/');
    }
}

if (!function_exists('reiss_get_language_codes')) {
    function reiss_get_language_codes() {
        return array(
            'af','ar','az','de','el','es','fa','fr','id','it','ja','ko','ms','nl','pl','pt','ru','sv','th','tr','vi','zh-cn'
        );
    }
}

if (!function_exists('reiss_get_supported_langs')) {
    function reiss_get_supported_langs() {
        return array_values(array_unique(array_merge(array(reiss_get_default_lang()), reiss_get_language_codes())));
    }
}

if (!function_exists('reiss_get_locale_map')) {
    function reiss_get_locale_map() {
        return array(
            'en'    => 'en_US',
            'af'    => 'af_ZA',
            'ar'    => 'ar_SA',
            'az'    => 'az_AZ',
            'de'    => 'de_DE',
            'el'    => 'el_GR',
            'es'    => 'es_ES',
            'fa'    => 'fa_IR',
            'fr'    => 'fr_FR',
            'id'    => 'id_ID',
            'it'    => 'it_IT',
            'ja'    => 'ja_JP',
            'ko'    => 'ko_KR',
            'ms'    => 'ms_MY',
            'nl'    => 'nl_NL',
            'pl'    => 'pl_PL',
            'pt'    => 'pt_PT',
            'ru'    => 'ru_RU',
            'sv'    => 'sv_SE',
            'th'    => 'th_TH',
            'tr'    => 'tr_TR',
            'vi'    => 'vi_VN',
            'zh-cn' => 'zh_CN',
        );
    }
}

if (!function_exists('reiss_get_html_lang_map')) {
    function reiss_get_html_lang_map() {
        return array(
            'en'    => 'en',
            'af'    => 'af',
            'ar'    => 'ar',
            'az'    => 'az',
            'de'    => 'de',
            'el'    => 'el',
            'es'    => 'es',
            'fa'    => 'fa',
            'fr'    => 'fr',
            'id'    => 'id',
            'it'    => 'it',
            'ja'    => 'ja',
            'ko'    => 'ko',
            'ms'    => 'ms',
            'nl'    => 'nl',
            'pl'    => 'pl',
            'pt'    => 'pt',
            'ru'    => 'ru',
            'sv'    => 'sv',
            'th'    => 'th',
            'tr'    => 'tr',
            'vi'    => 'vi',
            'zh-cn' => 'zh-CN',
        );
    }
}

if (!function_exists('reiss_normalize_path')) {
    function reiss_normalize_path($path) {
        $path = '/' . ltrim((string) $path, '/');
        $path = preg_replace('#/+#', '/', $path);

        if ($path !== '/' && substr($path, -1) !== '/') {
            $path .= '/';
        }

        return $path;
    }
}

if (!function_exists('reiss_get_current_lang')) {
    function reiss_get_current_lang() {
        $current_path = reiss_get_current_request_path();
        $current_lang = reiss_get_default_lang();

        if (preg_match('#^/([a-zA-Z]{2,3}(?:-[a-zA-Z]{2})?)(?:/|$)#', $current_path, $matches)) {
            $current_lang = strtolower($matches[1]);
        }

        if (!in_array($current_lang, reiss_get_supported_langs(), true)) {
            $current_lang = reiss_get_default_lang();
        }

        return $current_lang;
    }
}

if (!function_exists('reiss_get_current_lang_path')) {
    function reiss_get_current_lang_path() {
        $current_path = reiss_get_current_request_path();
        $current_lang = reiss_get_current_lang();
        $default_lang = reiss_get_default_lang();
        $path = $current_path;

        if ($current_lang !== $default_lang) {
            $path = preg_replace('#^/' . preg_quote($current_lang, '#') . '(?=/|$)#i', '', $path);
        }

        if ($path === '' || $path === false) {
            $path = '/';
        }

        return reiss_normalize_path($path);
    }
}

if (!function_exists('reiss_lang_url')) {
    function reiss_lang_url($host, $lang, $default, $path) {
        $host = rtrim((string) $host, '/');
        $path = reiss_normalize_path($path);

        if ($lang === $default) {
            return $host . $path;
        }

        return $host . '/' . rawurlencode($lang) . $path;
    }
}

if (!function_exists('reiss_strip_lang_from_path')) {
    function reiss_strip_lang_from_path($path, $supported_langs) {
        $path = (string) $path;
        $path_only = parse_url($path, PHP_URL_PATH);

        if (!is_string($path_only) || $path_only === '') {
            $path_only = '/';
        }

        foreach ($supported_langs as $lang_code) {
            if ($lang_code === reiss_get_default_lang()) {
                continue;
            }

            $pattern = '#^/' . preg_quote($lang_code, '#') . '(?=/|$)#i';

            if (preg_match($pattern, $path_only)) {
                $path_only = preg_replace($pattern, '', $path_only);
                break;
            }
        }

        if ($path_only === '' || $path_only === false) {
            $path_only = '/';
        }

        return reiss_normalize_path($path_only);
    }
}

if (!function_exists('reiss_localize_url')) {
    function reiss_localize_url($url, $target_lang, $default_lang, $host, $supported_langs) {
        $url = trim((string) $url);

        if ($url === '') {
            return $url;
        }

        $parsed = wp_parse_url($url);

        if (!is_array($parsed)) {
            return $url;
        }

        $target_host = wp_parse_url($host, PHP_URL_HOST);
        $url_host = isset($parsed['host']) ? $parsed['host'] : '';

        if ($url_host && $target_host && strtolower($url_host) !== strtolower($target_host)) {
            return $url;
        }

        $path = isset($parsed['path']) ? $parsed['path'] : '/';
        $clean = reiss_strip_lang_from_path($path, $supported_langs);
        $localized = reiss_lang_url($host, $target_lang, $default_lang, $clean);

        if (!empty($parsed['query'])) {
            $localized .= '?' . $parsed['query'];
        }

        if (!empty($parsed['fragment'])) {
            $localized .= '#' . $parsed['fragment'];
        }

        return $localized;
    }
}

if (!function_exists('reiss_replace_host_urls_in_value')) {
    function reiss_replace_host_urls_in_value($value, $current_lang, $default_lang, $host, $supported_langs) {
        if (is_array($value)) {
            foreach ($value as $k => $v) {
                $value[$k] = reiss_replace_host_urls_in_value($v, $current_lang, $default_lang, $host, $supported_langs);
            }
            return $value;
        }

        if (is_string($value) && preg_match('#^https?://#i', $value)) {
            return reiss_localize_url($value, $current_lang, $default_lang, $host, $supported_langs);
        }

        return $value;
    }
}

if (!function_exists('reiss_replace_host_urls_in_json_string')) {
    function reiss_replace_host_urls_in_json_string($json, $current_lang, $default_lang, $host, $supported_langs) {
        if (!is_string($json) || $json === '') {
            return $json;
        }

        $host_no_trailing = rtrim($host, '/');
        $host_quoted = preg_quote($host_no_trailing, '#');

        foreach ($supported_langs as $lang_code) {
            if ($lang_code === $default_lang) {
                continue;
            }

            $json = preg_replace(
                '#'.$host_quoted.'/' . preg_quote($lang_code, '#') . '(/?)#i',
                $host_no_trailing . '$1',
                $json
            );
        }

        $path = reiss_get_current_lang_path();
        $current_url = reiss_lang_url($host, $current_lang, $default_lang, $path);
        $default_url = reiss_lang_url($host, $default_lang, $default_lang, $path);

        $json = str_replace(
            array(
                wp_json_encode(rtrim($default_url, '/') . '/#article'),
                wp_json_encode(rtrim($default_url, '/') . '/#breadcrumb'),
                wp_json_encode(rtrim($default_url, '/') . '/#primaryimage'),
                wp_json_encode(rtrim($default_url, '/') . '/#webpage'),
                wp_json_encode(rtrim($default_url, '/') . '/')
            ),
            array(
                wp_json_encode(rtrim($current_url, '/') . '/#article'),
                wp_json_encode(rtrim($current_url, '/') . '/#breadcrumb'),
                wp_json_encode(rtrim($current_url, '/') . '/#primaryimage'),
                wp_json_encode(rtrim($current_url, '/') . '/#webpage'),
                wp_json_encode(rtrim($current_url, '/') . '/')
            ),
            $json
        );

        $decoded = json_decode($json, true);
        if (json_last_error() === JSON_ERROR_NONE && is_array($decoded)) {
            $decoded = reiss_replace_host_urls_in_value($decoded, $current_lang, $default_lang, $host, $supported_langs);
            return wp_json_encode($decoded, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
        }

        return $json;
    }
}

if (!function_exists('reiss_get_current_url')) {
    function reiss_get_current_url() {
        return reiss_lang_url(
            reiss_get_host(),
            reiss_get_current_lang(),
            reiss_get_default_lang(),
            reiss_get_current_lang_path()
        );
    }
}

if (!function_exists('reiss_get_default_url')) {
    function reiss_get_default_url() {
        return reiss_lang_url(
            reiss_get_host(),
            reiss_get_default_lang(),
            reiss_get_default_lang(),
            reiss_get_current_lang_path()
        );
    }
}

if (!function_exists('reiss_get_current_og_locale')) {
    function reiss_get_current_og_locale() {
        $map = reiss_get_locale_map();
        $lang = reiss_get_current_lang();

        return isset($map[$lang]) ? $map[$lang] : 'en_US';
    }
}

if (!function_exists('reiss_get_current_html_lang')) {
    function reiss_get_current_html_lang() {
        $map = reiss_get_html_lang_map();
        $lang = reiss_get_current_lang();

        return isset($map[$lang]) ? $map[$lang] : 'en';
    }
}

if (!function_exists('reiss_get_schema_language')) {
    function reiss_get_schema_language() {
        $lang = reiss_get_current_lang();

        if ($lang === 'en') {
            return 'en-US';
        }

        $map = array(
            'zh-cn' => 'zh-CN',
        );

        return isset($map[$lang]) ? $map[$lang] : $lang;
    }
}

// =========================================================================
// Language Attributes
// =========================================================================
function reiss_filter_language_attributes($output) {
    $html_lang = reiss_get_current_html_lang();
    $output = preg_replace('/lang=("|\')[^"\']*("|\')/i', 'lang="' . esc_attr($html_lang) . '"', $output);

    if (stripos($output, 'lang=') === false) {
        $output .= ' lang="' . esc_attr($html_lang) . '"';
    }

    return $output;
}
add_filter('language_attributes', 'reiss_filter_language_attributes', 20);

// =========================================================================
// Yoast SEO Multilingual Fix - Base Filters
// =========================================================================
function reiss_filter_wpseo_canonical($canonical) {
    if (is_search() || is_404()) {
        return $canonical;
    }

    $current_lang = reiss_get_current_lang();
    $default_lang = reiss_get_default_lang();
    $host = reiss_get_host();
    $current_path = reiss_get_current_lang_path();
    $supported_langs = reiss_get_supported_langs();

    if (!empty($canonical)) {
        return reiss_localize_url($canonical, $current_lang, $default_lang, $host, $supported_langs);
    }

    return reiss_lang_url($host, $current_lang, $default_lang, $current_path);
}
add_filter('wpseo_canonical', 'reiss_filter_wpseo_canonical', 99);

function reiss_filter_wpseo_opengraph_url($url) {
    $current_lang = reiss_get_current_lang();
    $default_lang = reiss_get_default_lang();
    $host = reiss_get_host();
    $current_path = reiss_get_current_lang_path();
    $supported_langs = reiss_get_supported_langs();

    if (!empty($url)) {
        return reiss_localize_url($url, $current_lang, $default_lang, $host, $supported_langs);
    }

    return reiss_lang_url($host, $current_lang, $default_lang, $current_path);
}
add_filter('wpseo_opengraph_url', 'reiss_filter_wpseo_opengraph_url', 99);

function reiss_filter_wpseo_locale($locale) {
    return reiss_get_current_og_locale();
}
add_filter('wpseo_locale', 'reiss_filter_wpseo_locale', 99);

function reiss_filter_wpseo_schema_graph($graph) {
    if (!is_array($graph)) {
        return $graph;
    }

    $current_lang = reiss_get_current_lang();
    $default_lang = reiss_get_default_lang();
    $host = reiss_get_host();
    $supported_langs = reiss_get_supported_langs();
    $schema_lang = reiss_get_schema_language();

    foreach ($graph as $i => $piece) {
        $graph[$i] = reiss_replace_host_urls_in_value($piece, $current_lang, $default_lang, $host, $supported_langs);

        if (is_array($graph[$i]) && isset($graph[$i]['inLanguage'])) {
            $graph[$i]['inLanguage'] = $schema_lang;
        }
    }

    return $graph;
}
add_filter('wpseo_schema_graph', 'reiss_filter_wpseo_schema_graph', 999);

function reiss_filter_wpseo_json_ld_output($data) {
    if (!is_array($data)) {
        return $data;
    }

    $current_lang = reiss_get_current_lang();
    $default_lang = reiss_get_default_lang();
    $host = reiss_get_host();
    $supported_langs = reiss_get_supported_langs();
    $schema_lang = reiss_get_schema_language();

    $data = reiss_replace_host_urls_in_value($data, $current_lang, $default_lang, $host, $supported_langs);

    if (!empty($data['@graph']) && is_array($data['@graph'])) {
        foreach ($data['@graph'] as $index => $node) {
            if (!is_array($node)) {
                continue;
            }

            if (isset($node['inLanguage'])) {
                $data['@graph'][$index]['inLanguage'] = $schema_lang;
            }

            $data['@graph'][$index] = reiss_replace_host_urls_in_value($node, $current_lang, $default_lang, $host, $supported_langs);
        }
    }

    return $data;
}
add_filter('wpseo_json_ld_output', 'reiss_filter_wpseo_json_ld_output', 999);

// =========================================================================
// Yoast SEO Multilingual Fix - Final Head Output Override
// =========================================================================
if (!function_exists('reiss_start_wpseo_head_buffer')) {
    function reiss_start_wpseo_head_buffer() {
        ob_start('reiss_filter_wpseo_head_output');
    }
}

if (!function_exists('reiss_end_wpseo_head_buffer')) {
    function reiss_end_wpseo_head_buffer() {
        if (ob_get_level() > 0) {
            @ob_end_flush();
        }
    }
}

if (!function_exists('reiss_filter_wpseo_head_output')) {
    function reiss_filter_wpseo_head_output($html) {
        if (!is_string($html) || trim($html) === '') {
            return $html;
        }

        if (strpos($html, 'yoast') === false && strpos($html, 'og:locale') === false && strpos($html, 'application/ld+json') === false) {
            return $html;
        }

        $current_lang = reiss_get_current_lang();
        $default_lang = reiss_get_default_lang();
        $host = reiss_get_host();
        $supported_langs = reiss_get_supported_langs();
        $current_url = reiss_get_current_url();
        $current_og_locale = reiss_get_current_og_locale();
        $schema_lang = reiss_get_schema_language();

        $html = preg_replace(
            '#<meta\s+property=("|\')og:locale\1\s+content=("|\')[^"\']*("|\')\s*/?>#i',
            '<meta property="og:locale" content="' . esc_attr($current_og_locale) . '">',
            $html
        );

        $html = preg_replace(
            '#<meta\s+property=("|\')og:url\1\s+content=("|\')[^"\']*("|\')\s*/?>#i',
            '<meta property="og:url" content="' . esc_url($current_url) . '">',
            $html
        );

        $html = preg_replace(
            '#<link\s+rel=("|\')canonical\1\s+href=("|\')[^"\']*("|\')\s*/?>#i',
            '<link rel="canonical" href="' . esc_url($current_url) . '">',
            $html
        );

        $html = preg_replace_callback(
            '#<script[^>]*type=("|\')application/ld\+json\1[^>]*>(.*?)</script>#is',
            function ($matches) use ($current_lang, $default_lang, $host, $supported_langs, $schema_lang) {
                $script_open = preg_replace('#>(.*?)$#s', '>', $matches[0]);
                $json = $matches[2];

                $decoded = json_decode($json, true);

                if (json_last_error() === JSON_ERROR_NONE && is_array($decoded)) {
                    $decoded = reiss_replace_host_urls_in_value($decoded, $current_lang, $default_lang, $host, $supported_langs);

                    if (!empty($decoded['@graph']) && is_array($decoded['@graph'])) {
                        foreach ($decoded['@graph'] as $i => $node) {
                            if (!is_array($node)) {
                                continue;
                            }

                            $decoded['@graph'][$i] = reiss_replace_host_urls_in_value($node, $current_lang, $default_lang, $host, $supported_langs);

                            if (isset($decoded['@graph'][$i]['inLanguage'])) {
                                $decoded['@graph'][$i]['inLanguage'] = $schema_lang;
                            }
                        }
                    } elseif (isset($decoded['inLanguage'])) {
                        $decoded['inLanguage'] = $schema_lang;
                    }

                    $json = wp_json_encode($decoded, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
                } else {
                    $json = reiss_replace_host_urls_in_json_string($json, $current_lang, $default_lang, $host, $supported_langs);
                }

                return preg_replace(
                    '#<script[^>]*type=("|\')application/ld\+json\1[^>]*>.*?</script>#is',
                    $script_open . $json . '</script>',
                    $matches[0]
                );
            },
            $html
        );

        return $html;
    }
}

add_action('wpseo_head', 'reiss_start_wpseo_head_buffer', 0);
add_action('wpseo_head', 'reiss_end_wpseo_head_buffer', 999999);