// ==UserScript==
// @name         广谈大湾网 · 今日发帖数
// @namespace    local.dww.today-threads
// @version      1.0.0
// @description  在论坛主题管理的主题总数右侧显示北京时间当日新增主题数（不含回复）。
// @match        https://www.dww11.com/admin.php*
// @match        https://dww11.com/admin.php*
// @run-at       document-idle
// @grant        none
// ==/UserScript==

(() => {
    'use strict';

    // 不要添加 @noframes：管理列表就在后台的 main iframe 内。
    const params = new URLSearchParams(location.search);
    if (params.get('action') !== 'threads' || params.get('operation')) return;

    const header = [...document.querySelectorAll('#cpform th.partition')]
        .find(el => /^\s*(?:最新主题数|符合条件的主题数)\s*\d+/.test(el.textContent));
    const form = document.querySelector('#threadforum');
    if (!header || !form || document.getElementById('dww-today-threads')) return;

    const badge = document.createElement('span');
    badge.id = 'dww-today-threads';
    badge.style.cssText = 'display:inline-block;margin-left:20px;color:#008640;white-space:nowrap;';
    const label = document.createElement('span');
    label.setAttribute('role', 'status');
    label.setAttribute('aria-live', 'polite');
    label.textContent = '今日发帖数：统计中…';
    const refresh = document.createElement('button');
    refresh.type = 'button';
    refresh.textContent = '刷新';
    refresh.style.cssText = 'margin-left:8px;padding:0;border:0;background:none;color:#2369a0;cursor:pointer;font:inherit;font-weight:normal;';
    badge.append(label, refresh);
    header.append(badge);

    function dayRange(now = new Date()) {
        // 用 UTC 计算固定东八区日期，避免电脑时区及夏令时影响。
        const offset = 8 * 60 * 60 * 1000;
        const localDay = new Date(now.getTime() + offset).toISOString().slice(0, 10);
        const previousDay = new Date(Date.parse(localDay + 'T00:00:00Z') - 86400000)
            .toISOString().slice(0, 10);
        // Discuz 原生查询使用 dateline > starttime 且 <= endtime。
        // 从前一天最后一秒之后开始，完整涵盖今日 00:00:00 至 23:59:59。
        return [localDay, `${previousDay} 23:59:59`, `${localDay} 23:59:59`];
    }

    async function queryCount(start, end) {
        const hash = form.querySelector('input[name="formhash"]')?.value;
        if (!hash) throw new Error('未找到后台查询凭据，请重新登录后刷新');

        // 只提交查询字段，不读取/提交 #cpform 的批量修改、删除字段。
        // 不继承当前筛选条件，今日数始终表示全部可查询版块的新增主题。
        const body = new URLSearchParams({
            formhash: hash, searchsubmit: '1', detail: '1',
            page: '1', pp: '', perpage: '20',
            inforum: 'all', intype: '', insort: 'all',
            starttime: start, endtime: end,
            users: '', keywords: '', viewsmore: '', viewsless: '',
            repliesmore: '', repliesless: '', readpermmore: '',
            pricemore: '', noreplydays: '', savethread: '0', hidethread: '0'
        });
        const endpoint = new URL('admin.php?action=threads', location.href);
        const controller = new AbortController();
        const timer = setTimeout(() => controller.abort(), 25000);
        try {
            const response = await fetch(endpoint.href, {
                method: 'POST', credentials: 'same-origin', cache: 'no-store',
                body, signal: controller.signal
            });
            if (!response.ok) throw new Error(`后台返回 HTTP ${response.status}`);
            const buffer = await response.arrayBuffer();
            const charset = response.headers.get('content-type')?.match(/charset=([^;\s]+)/i)?.[1]
                || document.characterSet || 'utf-8';
            const html = new TextDecoder(charset).decode(buffer);
            const result = new DOMParser().parseFromString(html, 'text/html');
            const summary = [...result.querySelectorAll('#cpform th.partition')]
                .map(el => el.textContent.match(/^\s*符合条件的主题数\s*([\d,]+)/))
                .find(Boolean);
            if (summary) {
                // 必须是按指定日期查询的结果，避免把默认最新主题数误报成今日数。
                const returnedStart = result.querySelector('#threadforum [name="starttime"]')?.value;
                const returnedEnd = result.querySelector('#threadforum [name="endtime"]')?.value;
                if (returnedStart !== start || returnedEnd !== end) {
                    throw new Error('后台未返回指定日期条件，无法确认统计结果');
                }
                return Number(summary[1].replaceAll(',', ''));
            }
            throw new Error('未读取到统计结果，可能登录已过期或后台查询异常');
        } finally {
            clearTimeout(timer);
        }
    }

    let busy = false;
    let lastDay = '';
    async function update() {
        if (busy) return;
        busy = true;
        refresh.disabled = true;
        const [day, start, end] = dayRange();
        label.textContent = '今日发帖数：统计中…';
        badge.style.color = '#008640';
        try {
            const count = await queryCount(start, end);
            if (dayRange()[0] !== day) {
                // 请求恰好跨过午夜，不把昨日结果标为今日。
                label.textContent = '今日发帖数：请刷新';
                lastDay = '';
                return;
            }
            lastDay = day;
            label.textContent = `今日发帖数：${count}`;
            badge.title = `北京时间 ${day} 新增主题，不含回复；以后台正常主题查询口径为准。更新于 ${new Date().toLocaleTimeString('zh-CN', { timeZone: 'Asia/Shanghai', hour12: false })}`;
        } catch (error) {
            label.textContent = '今日发帖数：读取失败';
            badge.style.color = '#c0392b';
            badge.title = error.name === 'AbortError' ? '查询超时，请点击刷新重试' : error.message;
        } finally {
            busy = false;
            refresh.disabled = false;
        }
    }

    refresh.addEventListener('click', update);
    // 每分钟一条后台只读查询；后台标签页暂停轮询。
    setInterval(() => { if (!document.hidden) update(); }, 60000);
    document.addEventListener('visibilitychange', () => {
        if (!document.hidden && lastDay !== dayRange()[0]) update();
    });
    update();
})();