<?php
/**
 * AKSRT Content Visibility
 *
 * Central access policy for shortcode-gated content and paid-content runtime.
 *
 * @package AKSRT
 */

defined('ABSPATH') || exit;

class AKSRT_Content_Visibility {

    private static $instance = null;

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

        return self::$instance;
    }

    public function init(): void {
        // 短代码注册统一在 AKSRT_Shortcodes（registry）；本类只提供渲染实现。
        add_action('wp_ajax_aksrt_check_visibility', [$this, 'ajax_check_visibility']);
        add_action('wp_ajax_nopriv_aksrt_check_visibility', [$this, 'ajax_check_visibility']);
    }

    /**
     * @param int|WP_Post|null $post
     * @return array<string, mixed>
     */
    public static function get_post_access_state($post = null, int $user_id = 0): array {
        $resource_post = get_post($post);
        $uid = $user_id > 0 ? $user_id : get_current_user_id();
        $pay_meta = function_exists('aksrt_get_pay_meta')
            ? aksrt_get_pay_meta($resource_post)
            : AKSRT_Domain_Model::default_pay_meta();
        $pay_type = AKSRT_Domain_Model::normalize_pay_type((string) ($pay_meta['pay_type'] ?? AKSRT_Domain_Model::PAY_TYPE_NO));
        $priced = function_exists('aksrt_get_user_pay_price')
            ? aksrt_get_user_pay_price($resource_post, $uid)
            : null;
        $pay_modo = is_array($priced)
            ? ((($priced['modo'] ?? '0') === 'points') ? 'points' : '0')
            : ((($pay_meta['pay_modo'] ?? '0') === 'points') ? 'points' : '0');
        $price = is_array($priced)
            ? (float) ($priced['amount'] ?? 0)
            : (($pay_modo === 'points')
                ? (float) ($pay_meta['points_price'] ?? 0)
                : (float) ($pay_meta['price'] ?? 0));
        $paid_settings = class_exists('AKSRT_Settings')
            ? AKSRT_Settings::get_paid_content_settings()
            : [
                'download_login' => true,
                'download_credit' => true,
                'download_captcha' => false,
            ];

        $state = [
            'post_id' => $resource_post instanceof WP_Post ? (int) $resource_post->ID : 0,
            'pay_type' => $pay_type,
            'pay_modo' => $pay_modo,
            'price' => $price,
            'need_login' => false,
            'need_purchase' => false,
            'need_vip' => false,
            'require_captcha' => false,
            'has_paid_access' => false,
            'can_view' => true,
            'can_download' => true,
            'download_cost' => 0,
            'pay_limit' => 0,
            'user_vip_level' => 0,
        ];

        if (!($resource_post instanceof WP_Post)) {
            $state['can_view'] = false;
            $state['can_download'] = false;
            return $state;
        }

        if ($pay_type === AKSRT_Domain_Model::PAY_TYPE_NO) {
            $state['has_paid_access'] = true;
            return $state;
        }

        $has_free_access = $price <= 0 && $pay_type !== AKSRT_Domain_Model::PAY_TYPE_VIP;
        $pay_limit = (int) ($pay_meta['pay_limit'] ?? 0);
        if (!in_array($pay_limit, [0, 1, 2], true)) {
            $pay_limit = 0;
        }
        $state['pay_limit'] = $pay_limit;
        $has_paid_order = false;

        if ($uid > 0 && class_exists('AKSRT_Order')) {
            $has_paid_order = AKSRT_Order::get_instance()->has_paid_access(
                $uid,
                AKSRT_Domain_Model::ORDER_PRODUCT_RESOURCE,
                (int) $resource_post->ID
            );
        }

        $has_vip_access = false;
        $user_vip_level = is_array($priced) ? (int) ($priced['vip_level'] ?? 0) : 0;
        if ($uid > 0) {
            if ($user_vip_level <= 0 && function_exists('aksrt_get_user_vip_level')) {
                $user_vip_level = aksrt_get_user_vip_level($uid);
            }
            if (function_exists('aksrt_is_vip_exempt') && aksrt_is_vip_exempt($uid)) {
                $has_vip_access = true;
                $user_vip_level = max($user_vip_level, 2);
            } elseif ($pay_type === AKSRT_Domain_Model::PAY_TYPE_VIP || $pay_limit > 0) {
                $has_vip_access = $user_vip_level >= max(1, $pay_limit);
            } elseif ($user_vip_level > 0) {
                // VIP tier pricing may zero cost; still track membership.
                $has_vip_access = $pay_limit <= 0 || $user_vip_level >= $pay_limit;
            }
        }
        $state['user_vip_level'] = $user_vip_level;

        // Member-only purchase restriction (Zibll pay_limit).
        if ($pay_limit > 0 && $pay_type !== AKSRT_Domain_Model::PAY_TYPE_NO) {
            $state['need_vip'] = $uid <= 0 || $user_vip_level < $pay_limit;
            $allowed_member = $uid > 0 && $user_vip_level >= $pay_limit;
            if ($pay_type === AKSRT_Domain_Model::PAY_TYPE_DOWNLOAD) {
                // Cash: order gate only. Points: cashier once → paid order zeros cost.
                $download_cost = 0;
                if ($pay_modo === 'points' && $price > 0 && !$has_paid_order) {
                    $download_cost = (int) ceil($price);
                }
                if ($allowed_member && $price <= 0) {
                    $download_cost = 0;
                }
                $state['download_cost'] = max(0, $download_cost);
                $state['need_login'] = $uid <= 0;
                $state['need_purchase'] = $allowed_member && $price > 0 && !$has_paid_order;
                $state['has_paid_access'] = $allowed_member && ($has_paid_order || $price <= 0);
                $state['can_view'] = true;
                $state['can_download'] = $allowed_member && ($uid > 0) && ($has_paid_order || $price <= 0);
                if (!$allowed_member) {
                    $state['can_download'] = false;
                    $state['has_paid_access'] = false;
                    $state['need_purchase'] = false;
                    $state['need_vip'] = true;
                }
                return $state;
            }

            // reading/gallery/video with pay_limit
            if ($allowed_member) {
                $state['has_paid_access'] = $has_paid_order || $price <= 0;
                $state['need_purchase'] = !$state['has_paid_access'];
                $state['need_vip'] = false;
            } else {
                $state['has_paid_access'] = false;
                $state['need_purchase'] = false;
                $state['need_vip'] = true;
            }
            $state['can_view'] = $state['has_paid_access'];
            $state['can_download'] = false;
            return $state;
        }

        if ($pay_type === AKSRT_Domain_Model::PAY_TYPE_DOWNLOAD) {
            // Zibll: cash = order unlock; points = one-shot cashier order (not per-download deduct).
            $download_cost = 0;
            if ($pay_modo === 'points' && $price > 0 && !$has_paid_order) {
                $download_cost = (int) ceil($price);
            }
            $state['download_cost'] = max(0, $download_cost);

            $free_logged_show = !empty($paid_settings['free_logged_show']);
            $state['need_login'] = !empty($paid_settings['download_login'])
                || !empty($pay_meta['require_login'])
                || ($free_logged_show && $price <= 0);
            $state['require_captcha'] = !empty($paid_settings['download_captcha']) || !empty($pay_meta['require_captcha']);

            $state['need_purchase'] = !$has_paid_order && $price > 0;
            $state['has_paid_access'] = $has_paid_order || $price <= 0 || $has_free_access;
            $state['can_view'] = true;
            $state['can_download'] = (!$state['need_login'] || $uid > 0) && ($has_paid_order || $price <= 0);

            return $state;
        }

        if ($pay_type === AKSRT_Domain_Model::PAY_TYPE_VIP) {
            $state['need_vip'] = true;
            $state['has_paid_access'] = $has_vip_access;
            $state['can_view'] = $has_vip_access;
            $state['can_download'] = false;

            return $state;
        }

        $state['need_login'] = !empty($pay_meta['require_login']);
        $state['need_purchase'] = !$has_free_access && !$has_paid_order;
        $state['has_paid_access'] = $has_free_access || $has_paid_order;
        // VIP free tier for reading etc. via amount.
        if (!$state['has_paid_access'] && $price <= 0 && $pay_type !== AKSRT_Domain_Model::PAY_TYPE_VIP) {
            $state['has_paid_access'] = true;
            $state['need_purchase'] = false;
        }
        $state['can_view'] = $state['has_paid_access'] && (!$state['need_login'] || $uid > 0);
        $state['can_download'] = false;

        return $state;
    }

    public static function can_view_paid_content($post = null, int $user_id = 0): bool {
        $state = self::get_post_access_state($post, $user_id);
        return !empty($state['can_view']);
    }

    /**
     * @param int|WP_Post|null $post
     * @return true|WP_Error
     */
    public static function can_download_resource($post = null, int $user_id = 0) {
        $resource_post = get_post($post);
        if (!($resource_post instanceof WP_Post) || !function_exists('aksrt_is_downloadable_content') || !aksrt_is_downloadable_content($resource_post)) {
            return new WP_Error('aksrt_not_downloadable', __('该内容未启用下载能力。', 'aksrt'));
        }

        $state = self::get_post_access_state($resource_post, $user_id);
        $uid = $user_id > 0 ? $user_id : get_current_user_id();

        if (($state['pay_type'] ?? '') !== AKSRT_Domain_Model::PAY_TYPE_DOWNLOAD) {
            return new WP_Error('aksrt_not_downloadable', __('该内容未启用下载能力。', 'aksrt'));
        }

        if (!empty($state['need_login']) && $uid <= 0) {
            return new WP_Error('aksrt_need_login', __('请先登录后再下载。', 'aksrt'), [
                'status' => 401,
                'login_url' => wp_login_url(get_permalink($resource_post)),
            ]);
        }

        // Free download + pay_free_logged_show (belt-and-suspenders with state.need_login).
        $cost = (int) ($state['download_cost'] ?? 0);
        $paid_settings = class_exists('AKSRT_Settings')
            ? AKSRT_Settings::get_paid_content_settings()
            : ['download_credit' => true, 'free_logged_show' => false];

        if ($cost <= 0 && !empty($paid_settings['free_logged_show']) && $uid <= 0) {
            return new WP_Error('aksrt_need_login', __('免费资源，请登录后下载。', 'aksrt'), [
                'status' => 401,
                'login_url' => wp_login_url(get_permalink($resource_post)),
            ]);
        }

        // Member-only (pay_limit).
        if (!empty($state['need_vip']) && empty($state['has_paid_access']) && empty($state['can_download'])) {
            $need_level = (int) ($state['pay_limit'] ?? 1);
            return new WP_Error('aksrt_need_vip', sprintf(
                /* translators: %d: required VIP level */
                __('该资源仅限 VIP%s 及以上会员购买/下载。', 'aksrt'),
                max(1, $need_level)
            ), [
                'status' => 403,
                'pay_limit' => $need_level,
            ]);
        }

        // Cash or points: require cashier purchase (resource order) before download token.
        if (!empty($state['need_purchase']) && empty($state['has_paid_access'])) {
            $pay_modo = (string) ($state['pay_modo'] ?? '0');
            $price = (float) ($state['price'] ?? 0);
            return new WP_Error('aksrt_need_purchase', __('请先购买后再下载。', 'aksrt'), [
                'status' => 402,
                'pay_modo' => $pay_modo,
                'amount' => $pay_modo === 'points' ? (int) ceil($price) : $price,
                'post_id' => (int) ($state['post_id'] ?? 0),
            ]);
        }

        // Zibll daily free-download quota (only when free / already unlocked).
        if ($cost <= 0 && function_exists('aksrt_check_free_download_quota')) {
            // Provide per-post overbuy price to quota error.
            $over_cb = static function ($over, $uid) use ($resource_post) {
                if (!($resource_post instanceof WP_Post) || !function_exists('aksrt_get_pay_meta')) {
                    return $over;
                }
                $m = aksrt_get_pay_meta($resource_post);
                return max(0.0, (float) ($m['download_limit_over_price'] ?? 0));
            };
            add_filter('aksrt_download_limit_over_price', $over_cb, 10, 2);
            $quota = aksrt_check_free_download_quota($uid, $cost);
            remove_filter('aksrt_download_limit_over_price', $over_cb, 10);
            if (is_wp_error($quota)) {
                $data = (array) $quota->get_error_data();
                $data['post_id'] = (int) ($state['post_id'] ?? 0);
                $data['pay_modo'] = (string) ($state['pay_modo'] ?? '0');
                return new WP_Error($quota->get_error_code(), $quota->get_error_message(), $data);
            }
        }

        return true;
    }

    public function render_hide_shortcode(array $atts, string $content = ''): string {
        $atts = shortcode_atts([
            'mode'    => 'comment',
            'message' => '',
            'pid'     => get_the_ID(),
        ], $atts, 'aksrt_hide');

        $mode = sanitize_key((string) $atts['mode']);
        $pid  = (int) $atts['pid'];
        $message = (string) $atts['message'];

        if ($pid <= 0) {
            return '';
        }

        if ($this->is_unlocked($mode, $pid)) {
            return '<div class="aksrt-hidden-content aksrt-hidden-content--unlocked">' . do_shortcode($content) . '</div>';
        }

        if ($message === '') {
            switch ($mode) {
                case 'comment':
                    $message = __('评论后查看隐藏内容', 'aksrt');
                    break;
                case 'login':
                    $message = __('登录后查看隐藏内容', 'aksrt');
                    break;
                case 'password':
                    $message = __('输入密码后查看隐藏内容', 'aksrt');
                    break;
                default:
                    $message = __('此内容已隐藏', 'aksrt');
            }
        }

        $wrapper_class = 'aksrt-hidden-content aksrt-hidden-content--locked aksrt-hidden-content--' . esc_attr($mode);
        $html = '<div class="' . $wrapper_class . '" data-aksrt-visibility-mode="' . esc_attr($mode) . '" data-aksrt-visibility-pid="' . esc_attr((string) $pid) . '">';
        $html .= '<div class="aksrt-hidden-content__message">';
        $html .= '<i class="fas fa-lock" aria-hidden="true"></i> ';
        $html .= '<span>' . esc_html($message) . '</span>';
        $html .= '</div>';

        if ($mode === 'password') {
            $html .= '<div class="aksrt-hidden-content__form">';
            $html .= '<input type="password" class="aksrt-hidden-content__password-input" placeholder="' . esc_attr__('请输入密码', 'aksrt') . '">';
            $html .= '<button type="button" class="aksrt-hidden-content__submit-btn btn-primary btn-sm">' . esc_html__('验证', 'aksrt') . '</button>';
            $html .= '</div>';
        }

        $html .= '</div>';

        return $html;
    }

    private function is_unlocked(string $mode, int $pid): bool {
        switch ($mode) {
            case 'comment':
                if (!is_user_logged_in()) {
                    return false;
                }

                return get_comments([
                    'post_id' => $pid,
                    'user_id' => get_current_user_id(),
                    'count' => true,
                    'status' => 'approve',
                ]) > 0;

            case 'login':
                return is_user_logged_in();

            case 'password':
                return !empty($_COOKIE['aksrt_hide_pwd_' . $pid]);

            default:
                return false;
        }
    }

    public function ajax_check_visibility(): void {
        check_ajax_referer('aksrt_visibility', '_nonce');

        $mode = sanitize_key((string) ($_POST['mode'] ?? ''));
        $pid  = (int) ($_POST['pid'] ?? 0);

        if ($pid <= 0 || !in_array($mode, ['comment', 'login', 'password'], true)) {
            wp_send_json_error(['message' => __('参数无效', 'aksrt')]);
        }

        if ($mode === 'password') {
            $password = sanitize_text_field((string) ($_POST['password'] ?? ''));
            $post_password = get_post_password($pid);
            if ($post_password === '' || $password !== $post_password) {
                wp_send_json_error(['message' => __('密码错误', 'aksrt')]);
            }

            setcookie('aksrt_hide_pwd_' . $pid, '1', time() + HOUR_IN_SECONDS, COOKIEPATH, COOKIE_DOMAIN, is_ssl(), true);
            wp_send_json_success(['message' => __('验证成功', 'aksrt')]);
        }

        if ($this->is_unlocked($mode, $pid)) {
            wp_send_json_success(['message' => __('已解锁', 'aksrt')]);
        }

        wp_send_json_error(['message' => __('未满足条件', 'aksrt')]);
    }
}