<?php
if (!defined('ABSPATH')) {
    exit;
}

function zib_bbs_get_daily_post_limit()
{
    $enabled = get_option('zib_bbs_daily_post_limit_enabled', '0');
    if (!$enabled || $enabled === '0') {
        return 0;
    }
    $limit = (int) get_option('zib_bbs_daily_post_limit', 0);
    return max(0, $limit);
}

function zib_bbs_get_user_today_post_count($user_id)
{
    $user_id = (int) $user_id;
    if (!$user_id) {
        return 0;
    }
    global $wpdb;
    $today_start = current_time('Y-m-d') . ' 00:00:00';
    $count = $wpdb->get_var(
        $wpdb->prepare(
            "SELECT COUNT(*) FROM {$wpdb->posts}
             WHERE post_type = 'forum_post'
               AND post_author = %d
               AND post_status IN ('publish', 'pending', 'draft')
               AND post_date >= %s",
            $user_id,
            $today_start
        )
    );
    return (int) $count;
}

function zib_bbs_check_daily_post_limit($user_id = 0)
{
    if (!$user_id) {
        $user_id = get_current_user_id();
    }
    $user_id = (int) $user_id;
    if (!$user_id) {
        return array(
            'allowed'   => true,
            'limit'     => 0,
            'count'     => 0,
            'remaining' => 0,
        );
    }
    if (user_can($user_id, 'manage_options')) {
        return array(
            'allowed'   => true,
            'limit'     => 0,
            'count'     => 0,
            'remaining' => 999,
        );
    }
    if (is_super_admin($user_id)) {
        return array(
            'allowed'   => true,
            'limit'     => 0,
            'count'     => 0,
            'remaining' => 999,
        );
    }
    if (function_exists('zib_bbs_user_is_forum_admin') && zib_bbs_user_is_forum_admin($user_id)) {
        return array(
            'allowed'   => true,
            'limit'     => 0,
            'count'     => 0,
            'remaining' => 999,
        );
    }
    $limit = zib_bbs_get_daily_post_limit();
    if ($limit === 0) {
        return array(
            'allowed'   => true,
            'limit'     => 0,
            'count'     => 0,
            'remaining' => 999,
        );
    }
    $count     = zib_bbs_get_user_today_post_count($user_id);
    $remaining = max(0, $limit - $count);
    $allowed   = ($count < $limit);
    return array(
        'allowed'   => $allowed,
        'limit'     => $limit,
        'count'     => $count,
        'remaining' => $remaining,
    );
}

function zib_bbs_daily_limit_pre_post($post_data)
{
    if (!empty($post_data['ID'])) {
        return;
    }
    $post_type = isset($post_data['post_type']) ? $post_data['post_type'] : '';
    if ($post_type !== 'forum_post') {
        return;
    }
    $user_id = !empty($post_data['post_author']) ? (int) $post_data['post_author'] : get_current_user_id();
    if (!$user_id) {
        return;
    }
    $check = zib_bbs_check_daily_post_limit($user_id);
    if (!$check['allowed']) {
        $msg = get_option('zib_bbs_daily_post_limit_msg', '');
        if (!$msg) {
            $msg = sprintf(
                '您今日发帖数量已达上限（%d/%d），请明天再试',
                $check['count'],
                $check['limit']
            );
        }
        if (function_exists('zib_send_json_error')) {
            zib_send_json_error(esc_html($msg));
        } else {
            wp_send_json(array(
                'error' => true,
                'ys'    => 'danger',
                'msg'   => esc_html($msg),
            ));
        }
        exit;
    }
}

function zib_bbs_daily_limit_notice()
{
    if (is_admin() || !is_user_logged_in()) {
        return;
    }
    $limit = zib_bbs_get_daily_post_limit();
    if ($limit === 0) {
        return;
    }
    $user_id = get_current_user_id();
    $check   = zib_bbs_check_daily_post_limit($user_id);
    if ($check['limit'] === 0) {
        return;
    }
    $remaining = $check['remaining'];
    $count     = $check['count'];
    if ($remaining <= 0) {
        $style_class = 'danger';
        $icon        = 'ban';
        $notice_text = sprintf(
            '您今日发帖数量已达上限，已发 <strong>%d</strong> 篇，限制 <strong>%d</strong> 篇，请明天再试',
            $count,
            $limit
        );
    } elseif ($remaining <= 2) {
        $style_class = 'warning';
        $icon        = 'exclamation-circle';
        $notice_text = sprintf(
            '今日剩余发帖次数：<strong>%d</strong> 次（已发 %d/%d）',
            $remaining,
            $count,
            $limit
        );
    } else {
        $style_class = 'info';
        $icon        = 'info-circle';
        $notice_text = sprintf(
            '今日剩余发帖次数：<strong>%d</strong> 次（已发 %d/%d）',
            $remaining,
            $count,
            $limit
        );
    }
    ?>
    <script type="text/javascript">
    (function() {
        function zibBbsDailyLimitNotice() {
            var formSelectors = [
                '.bbs-new-post-form',
                '.bbs-post-form',
                '#bbs-post-form',
                '.new-post-wrap',
                '.post-editor-wrap'
            ];
            var container = null;
            for (var i = 0; i < formSelectors.length; i++) {
                container = document.querySelector(formSelectors[i]);
                if (container) break;
            }
            if (!container) return;
            if (document.getElementById('zib-bbs-daily-limit-notice')) return;
            var notice = document.createElement('div');
            notice.id = 'zib-bbs-daily-limit-notice';
            notice.className = 'alert alert-' + <?php echo wp_json_encode($style_class); ?> + ' mb15';
            notice.style.cssText = 'padding: 10px 15px; border-radius: 4px; margin-bottom: 15px; font-size: 13px;';
            notice.innerHTML = '<i class="fa fa-' + <?php echo wp_json_encode($icon); ?> + '" aria-hidden="true"></i> ' + <?php echo wp_json_encode($notice_text); ?>;
            container.insertBefore(notice, container.firstChild);
        }
        if (document.readyState === 'loading') {
            document.addEventListener('DOMContentLoaded', zibBbsDailyLimitNotice);
        } else {
            zibBbsDailyLimitNotice();
        }
        setTimeout(zibBbsDailyLimitNotice, 1500);
    })();
    </script>
    <?php
}

function zib_bbs_daily_limit_ajax_check()
{
    $nonce = isset($_REQUEST['nonce']) ? sanitize_text_field($_REQUEST['nonce']) : '';
    if (!wp_verify_nonce($nonce, 'zib_bbs_daily_limit_nonce')) {
        wp_send_json_error(array('msg' => '安全验证失败，请刷新页面重试'));
        return;
    }
    if (!is_user_logged_in()) {
        wp_send_json_error(array('msg' => '请先登录'));
        return;
    }
    $user_id = get_current_user_id();
    $check   = zib_bbs_check_daily_post_limit($user_id);
    wp_send_json_success(array(
        'allowed'   => $check['allowed'],
        'limit'     => $check['limit'],
        'count'     => $check['count'],
        'remaining' => $check['remaining'],
        'msg'       => $check['allowed']
            ? sprintf('今日还可发帖 %d 次', $check['remaining'])
            : sprintf('今日发帖数量已达上限（%d/%d）', $check['count'], $check['limit']),
    ));
}

function zib_bbs_daily_limit_localize()
{
    if (is_admin()) {
        return;
    }
    ?>
    <script type="text/javascript">
    window.zibBbsDailyLimit = {
        ajaxurl: <?php echo wp_json_encode(admin_url('admin-ajax.php')); ?>,
        nonce: <?php echo wp_json_encode(wp_create_nonce('zib_bbs_daily_limit_nonce')); ?>
    };
    </script>
    <?php
}

function zib_bbs_daily_limit_admin_menu()
{
    add_options_page(
        '论坛每日发帖限制',
        '论坛发帖限制',
        'manage_options',
        'zib-bbs-daily-limit',
        'zib_bbs_daily_limit_admin_page'
    );
}

function zib_bbs_daily_limit_admin_settings_init()
{
    register_setting(
        'zib_bbs_daily_limit_group',
        'zib_bbs_daily_post_limit_enabled',
        array(
            'type'              => 'string',
            'sanitize_callback' => 'sanitize_text_field',
            'default'           => '0',
        )
    );
    register_setting(
        'zib_bbs_daily_limit_group',
        'zib_bbs_daily_post_limit',
        array(
            'type'              => 'integer',
            'sanitize_callback' => 'absint',
            'default'           => 10,
        )
    );
    register_setting(
        'zib_bbs_daily_limit_group',
        'zib_bbs_daily_post_limit_msg',
        array(
            'type'              => 'string',
            'sanitize_callback' => 'sanitize_text_field',
            'default'           => '',
        )
    );
    add_settings_section(
        'zib_bbs_daily_limit_section',
        '基本设置',
        'zib_bbs_daily_limit_section_callback',
        'zib-bbs-daily-limit'
    );
    add_settings_field(
        'zib_bbs_daily_post_limit_enabled',
        '启用发帖数量限制',
        'zib_bbs_daily_limit_field_enabled',
        'zib-bbs-daily-limit',
        'zib_bbs_daily_limit_section'
    );
    add_settings_field(
        'zib_bbs_daily_post_limit',
        '每日最大发帖数',
        'zib_bbs_daily_limit_field_count',
        'zib-bbs-daily-limit',
        'zib_bbs_daily_limit_section'
    );
    add_settings_field(
        'zib_bbs_daily_post_limit_msg',
        '超限提示消息',
        'zib_bbs_daily_limit_field_msg',
        'zib-bbs-daily-limit',
        'zib_bbs_daily_limit_section'
    );
}

function zib_bbs_daily_limit_section_callback()
{
    echo '<p style="color:#666;">配置论坛用户每天最多可以发布的帖子数量。管理员和论坛版主不受此限制约束。</p>';
}

function zib_bbs_daily_limit_field_enabled()
{
    $value = get_option('zib_bbs_daily_post_limit_enabled', '0');
    ?>
    <input type="hidden" name="zib_bbs_daily_post_limit_enabled" value="0" />
    <label>
        <input type="checkbox"
               name="zib_bbs_daily_post_limit_enabled"
               value="1"
               <?php checked('1', $value); ?> />
        开启后将对普通用户的每日论坛发帖数量进行限制
    </label>
    <?php
}

function zib_bbs_daily_limit_field_count()
{
    $value = (int) get_option('zib_bbs_daily_post_limit', 10);
    ?>
    <input type="number"
           id="zib_bbs_daily_post_limit"
           name="zib_bbs_daily_post_limit"
           value="<?php echo esc_attr($value); ?>"
           min="1"
           max="9999"
           step="1"
           style="width:100px;" />
    <p class="description">每个用户每天最多可在论坛发布的帖子数量（仅在启用限制时生效）。</p>
    <?php
}

function zib_bbs_daily_limit_field_msg()
{
    $value = get_option('zib_bbs_daily_post_limit_msg', '');
    ?>
    <input type="text"
           id="zib_bbs_daily_post_limit_msg"
           name="zib_bbs_daily_post_limit_msg"
           value="<?php echo esc_attr($value); ?>"
           style="width:400px;"
           placeholder="留空则使用默认提示：您今日发帖数量已达上限（X/X），请明天再试" />
    <p class="description">用户触发每日发帖限制时显示的提示消息，留空使用默认消息。</p>
    <?php
}

function zib_bbs_daily_limit_admin_page()
{
    if (!current_user_can('manage_options')) {
        wp_die('您没有访问此页面的权限');
    }
    $limit   = zib_bbs_get_daily_post_limit();
    $enabled = get_option('zib_bbs_daily_post_limit_enabled', '0');
    ?>
    <div class="wrap">
        <h1><?php echo esc_html(get_admin_page_title()); ?></h1>
        <?php
        if (isset($_GET['settings-updated']) && $_GET['settings-updated']) {
            echo '<div class="notice notice-success is-dismissible"><p>设置已保存。</p></div>';
        }
        ?>
        <?php if ($enabled && $enabled !== '0' && $limit > 0): ?>
        <div class="notice notice-info" style="margin: 15px 0;">
            <p>
                <strong>当前状态：</strong>已启用限制，每日最多发帖 <strong><?php echo esc_html($limit); ?></strong> 篇。
                管理员和论坛版主不受此限制约束。
            </p>
        </div>
        <?php else: ?>
        <div class="notice notice-warning" style="margin: 15px 0;">
            <p><strong>当前状态：</strong>未启用发帖数量限制，所有用户可不限次数发帖（在其他规则允许的前提下）。</p>
        </div>
        <?php endif; ?>
        <form method="post" action="options.php">
            <?php
            settings_fields('zib_bbs_daily_limit_group');
            do_settings_sections('zib-bbs-daily-limit');
            submit_button('保存设置');
            ?>
        </form>
        <hr />
        <h2>今日发帖统计</h2>
        <?php zib_bbs_daily_limit_admin_stats_table(); ?>
        <hr />
        <h2>使用说明</h2>
        <div style="background:#fff;padding:15px;border:1px solid #ddd;border-radius:4px;max-width:700px;">
            <ul style="list-style:disc;padding-left:20px;line-height:1.8;">
                <li>本功能仅限制 <strong>论坛帖子（forum_post）</strong> 类型的每日发布数量。</li>
                <li>限制基于 <strong>当天 00:00:00 至当前时间</strong> 内发布的帖子数量（包含已发布、待审核、草稿状态）。</li>
                <li><strong>超级管理员、后台管理员（manage_options）、论坛管理员、版主</strong>不受此限制约束。</li>
                <li>设置为 0 或关闭开关均可解除限制。</li>
                <li>限制触发后，系统将返回错误提示，帖子不会被保存。</li>
            </ul>
        </div>
    </div>
    <?php
}

function zib_bbs_daily_limit_admin_stats_table()
{
    global $wpdb;
    $today_start = current_time('Y-m-d') . ' 00:00:00';
    $results = $wpdb->get_results(
        $wpdb->prepare(
            "SELECT post_author, COUNT(*) as post_count
             FROM {$wpdb->posts}
             WHERE post_type = 'forum_post'
               AND post_status IN ('publish', 'pending', 'draft')
               AND post_date >= %s
             GROUP BY post_author
             ORDER BY post_count DESC
             LIMIT 20",
            $today_start
        )
    );
    if (empty($results)) {
        echo '<p style="color:#666;">今日暂无论坛发帖记录。</p>';
        return;
    }
    $limit = zib_bbs_get_daily_post_limit();
    echo '<table class="widefat striped" style="max-width:600px;">';
    echo '<thead><tr>';
    echo '<th>用户</th><th>今日发帖数</th>';
    if ($limit > 0) {
        echo '<th>限制 / 剩余</th>';
    }
    echo '</tr></thead><tbody>';
    foreach ($results as $row) {
        $user = get_userdata((int) $row->post_author);
        $name = $user ? esc_html($user->display_name) : '未知用户（ID: ' . (int) $row->post_author . '）';
        $count = (int) $row->post_count;
        $tr_style = ($limit > 0 && $count >= $limit) ? ' style="background:#fff3f3;"' : '';
        echo '<tr' . $tr_style . '>';
        echo '<td>' . $name . '</td>';
        echo '<td><strong>' . $count . '</strong></td>';
        if ($limit > 0) {
            $remaining = max(0, $limit - $count);
            $color     = $remaining <= 0 ? 'color:#c00;' : ($remaining <= 2 ? 'color:#e88400;' : '');
            echo '<td style="' . $color . '">' . $limit . ' / ' . $remaining . '</td>';
        }
        echo '</tr>';
    }
    echo '</tbody></table>';
    echo '<p class="description" style="margin-top:8px;">仅显示今日发帖数排名前 20 的用户（含发布、待审核、草稿状态）。</p>';
}

function zib_bbs_daily_post_limit_init()
{
    add_action('zib_pre_insert_post', 'zib_bbs_daily_limit_pre_post', 15);
    add_action('wp_footer', 'zib_bbs_daily_limit_notice', 20);
    add_action('wp_footer', 'zib_bbs_daily_limit_localize', 1);
    add_action('wp_ajax_zib_bbs_check_daily_limit', 'zib_bbs_daily_limit_ajax_check');
    add_action('admin_menu', 'zib_bbs_daily_limit_admin_menu');
    add_action('admin_init', 'zib_bbs_daily_limit_admin_settings_init');
}

zib_bbs_daily_post_limit_init();