<?php
/**
 * AKSRT IP Geolocation Service
 *
 * 提供 IP 归属地查询能力。支持多 provider、transient 缓存和统一状态输出。
 *
 * @package AKSRT
 */

defined('ABSPATH') || exit;

class AKSRT_IP_Geo {

    private static $instance = null;

    public static function get_instance(): self {
        if (null === self::$instance) self::$instance = new self();
        return self::$instance;
    }

    /**
     * 查询 IP 归属地
     *
     * @param string $ip    IPv4 or IPv6
     * @param bool   $force 管理端测试用：跳过「启用」开关与缓存，仍拒绝私有 IP
     * @return array{country: string, province: string, city: string, raw: array, reason?: string}
     */
    public function lookup(string $ip, bool $force = false): array {
        $config = $this->get_config();

        if (!$force && empty($config['ip_geo_enabled'])) {
            return $this->empty_result('disabled');
        }

        // 本地/私有 IP 跳过查询
        if ($this->is_private_ip($ip)) {
            return $this->empty_result('private_ip');
        }

        $cache_key = 'aksrt_ip_geo_' . md5($ip);
        $ttl       = max(3600, (int) ($config['ip_geo_cache_ttl'] ?? 86400));
        if (!$force) {
            $cached = get_transient($cache_key);
            if ($cached !== false && is_array($cached)) {
                return $cached;
            }
        }

        $provider = sanitize_key((string) ($config['ip_addr_sdk'] ?? ($config['ip_geo_provider'] ?? 'null')));
        $result   = $this->query_provider($provider, $ip, $config);

        if (!empty($result['province']) || !empty($result['city']) || !empty($result['country'])) {
            if (!$force) {
                set_transient($cache_key, $result, $ttl);
            }
            return $result;
        }

        if (empty($result['reason'])) {
            $result['reason'] = 'provider_empty';
        }

        return $result;
    }

    /**
     * 获取服务运行时状态
     */
    public function get_status(): array {
        $config   = $this->get_config();
        $provider = sanitize_key((string) ($config['ip_addr_sdk'] ?? ($config['ip_geo_provider'] ?? 'null')));
        $enabled  = !empty($config['ip_geo_enabled']);

        $missing = [];
        if ($enabled && $provider === 'qq') {
            if (empty($config['ip_addr_sdk_qq_appkey'])) $missing[] = 'ip_addr_sdk_qq_appkey';
            if (empty($config['ip_addr_sdk_qq_secretkey'])) $missing[] = 'ip_addr_sdk_qq_secretkey';
        }
        if ($enabled && $provider === 'amap') {
            if (empty($config['ip_addr_sdk_amap_appkey'])) $missing[] = 'ip_addr_sdk_amap_appkey';
            if (empty($config['ip_addr_sdk_amap_secretkey'])) $missing[] = 'ip_addr_sdk_amap_secretkey';
        }

        return [
            'enabled'        => $enabled,
            'provider'       => $provider,
            'configured'     => $enabled && empty($missing),
            'available'      => $enabled,
            'verified'       => !empty($config['ip_geo_verified']),
            'transport'      => 'http_api',
            'missing_fields' => $missing,
            'cache_ttl'      => (int) ($config['ip_geo_cache_ttl'] ?? 86400),
            'display'        => (array) ($config['ip_geo_display'] ?? ['comment']),
            'format'         => (string) ($config['ip_geo_format'] ?? 'province_city'),
        ];
    }

    /**
     * 格式化归属地显示文本
     */
    public function format(array $geo, string $format = ''): string {
        if ($format === '') {
            $config = $this->get_config();
            $format = (string) ($config['ip_geo_format'] ?? 'province_city');
        }

        switch ($format) {
            case 'province':
                return $geo['province'] ?? '';
            case 'country_province':
                return trim(($geo['country'] ?? '') . ' ' . ($geo['province'] ?? ''));
            case 'province_city':
            default:
                $parts = array_filter([$geo['province'] ?? '', $geo['city'] ?? '']);
                return implode(' ', $parts) ?: ($geo['country'] ?? '');
        }
    }

    private function get_config(): array {
        if (class_exists('AKSRT_Settings')) {
            return AKSRT_Settings::get_ip_geo_settings();
        }
        return ['ip_geo_enabled' => false];
    }

    private function query_provider(string $provider, string $ip, array $config): array {
        switch ($provider) {
            case 'qq':
                return $this->query_qq($ip, $config);
            case 'amap':
                return $this->query_amap($ip, $config);
            case 'polling':
                foreach (['qq', 'amap', 'null'] as $fallback) {
                    $result = $this->query_provider($fallback, $ip, $config);
                    if (!empty($result['province']) || !empty($result['city']) || !empty($result['country'])) {
                        return $result;
                    }
                }
                return $this->empty_result();
            case 'null':
            default:
                return $this->query_ip_api($ip);
        }
    }

    private function query_qq(string $ip, array $config): array {
        $appkey = trim((string) ($config['ip_addr_sdk_qq_appkey'] ?? ''));
        if ($appkey === '') {
            return $this->empty_result();
        }

        $url = add_query_arg([
            'ip'  => $ip,
            'key' => $appkey,
        ], 'https://apis.map.qq.com/ws/location/v1/ip');

        $response = wp_remote_get($url, [
            'timeout' => 8,
            'headers' => ['Accept' => 'application/json'],
        ]);
        if (is_wp_error($response)) return $this->empty_result();

        $data = json_decode(wp_remote_retrieve_body($response), true);
        if (!is_array($data) || (int) ($data['status'] ?? 1) !== 0) return $this->empty_result();

        $info = $data['result']['ad_info'] ?? [];
        return [
            'country'  => '中国',
            'province' => (string) ($info['province'] ?? ''),
            'city'     => (string) ($info['city'] ?? ''),
            'raw'      => $data,
        ];
    }

    private function query_amap(string $ip, array $config): array {
        $appkey = trim((string) ($config['ip_addr_sdk_amap_appkey'] ?? ''));
        if ($appkey === '') {
            return $this->empty_result();
        }

        $url = add_query_arg([
            'ip'  => $ip,
            'key' => $appkey,
        ], 'https://restapi.amap.com/v3/ip');

        $response = wp_remote_get($url, [
            'timeout' => 8,
            'headers' => ['Accept' => 'application/json'],
        ]);
        if (is_wp_error($response)) return $this->empty_result();

        $data = json_decode(wp_remote_retrieve_body($response), true);
        if (!is_array($data) || (string) ($data['status'] ?? '0') !== '1') return $this->empty_result();

        return [
            'country'  => '中国',
            'province' => (string) ($data['province'] ?? ''),
            'city'     => (string) ($data['city'] ?? ''),
            'raw'      => $data,
        ];
    }

    private function query_ip_api(string $ip): array {
        $response = wp_remote_get("http://ip-api.com/json/{$ip}?lang=zh-CN", [
            'timeout' => 5,
        ]);
        if (is_wp_error($response)) return $this->empty_result();

        $data = json_decode(wp_remote_retrieve_body($response), true);
        if (!is_array($data) || ($data['status'] ?? '') !== 'success') return $this->empty_result();

        return [
            'country'  => (string) ($data['country'] ?? ''),
            'province' => (string) ($data['regionName'] ?? ''),
            'city'     => (string) ($data['city'] ?? ''),
            'raw'      => $data,
        ];
    }

    private function is_private_ip(string $ip): bool {
        return !filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_NO_PRIV_RANGE | FILTER_FLAG_NO_RES_RANGE);
    }

    private function empty_result(string $reason = ''): array {
        $out = ['country' => '', 'province' => '', 'city' => '', 'raw' => []];
        if ($reason !== '') {
            $out['reason'] = $reason;
        }
        return $out;
    }
}