// ==UserScript==
 // @name         职教云下一节辅助工具
 // @namespace    https://icve.com.cn/
 // @version      1.0.0
 // @description  视频结束提醒、返回课程列表、定位下一节未完成课件
 // @match        *://*.icve.com.cn/*
 // @match        *://icve.com.cn/*
 // @match        *://*.zjy2.icve.com.cn/*
 // @run-at       document-idle
 // @grant        none
 // ==/UserScript==

 (() => {
   'use strict';

   if (window.top !== window.self) return;
   if (window.__zhijiaoHelperInstalled) return;
   window.__zhijiaoHelperInstalled = true;

   const PREFIX = '[职教云辅助]';

   const log = (...args) => console.log(PREFIX, ...args);

   const visible = el =>
     !!el &&
     el.isConnected &&
     el.getClientRects().length > 0;

   const textOf = el =>
     (el?.innerText || el?.textContent || '').trim();

   // 查找页面中可见的按钮或链接
   function findVisibleControl(pattern) {
     return [...document.querySelectorAll(
       'button, a, [role="button"]'
     )].find(el =>
       visible(el) &&
       pattern.test(textOf(el) ||
         el.getAttribute('aria-label') || '')
     );
   }

   // 创建辅助面板
   const panel = document.createElement('div');

   panel.style.cssText = `
     position:fixed;
     right:18px;
     bottom:20px;
     z-index:2147483647;
     width:250px;
     padding:14px;
     background:#fff;
     color:#25264b;
     border:1px solid #8174ff;
     border-radius:12px;
     box-shadow:0 5px 20px #0003;
     font:14px/1.7 Arial,sans-serif;
   `;

   panel.innerHTML = `
     <div style="font-weight:bold;margin-bottom:8px">
       职教云学习辅助
     </div>
     <div id="zj-status" style="margin-bottom:10px">
       正在识别页面……
     </div>
     <button id="zj-locate"
       style="padding:7px 10px;border:0;border-radius:7px;
       background:#6655ee;color:white;cursor:pointer">
       定位下一节
     </button>
     <button id="zj-return"
       style="padding:7px 10px;margin-left:5px;
       border:1px solid #aaa;border-radius:7px;
       background:white;cursor:pointer">
       返回列表
     </button>
     <div id="zj-result"
       style="margin-top:8px;color:#666;overflow-wrap:anywhere">
     </div>
   `;

   document.body.appendChild(panel);

   const status = panel.querySelector('#zj-status');
   const result = panel.querySelector('#zj-result');

   // 尝试识别课程列表中尚未完成的课件
   function findIncompleteLesson() {
     const progressNodes = [
       ...document.querySelectorAll('body *')
     ].filter(el => {
       if (!visible(el)) return false;
       if (el.children.length > 2) return false;

       const t = textOf(el);

       return /学习进度\s*[:：]\s*\d+(?:\.\d+)?\s*%/.test(t);
     });

     const lessons = [];
     const seen = new Set();

     for (const node of progressNodes) {
       const match = textOf(node).match(
         /学习进度\s*[:：]\s*(\d+(?:\.\d+)?)\s*%/
       );

       if (!match) continue;

       const progress = Number(match[1]);
       if (progress >= 100) continue;

       // 向上寻找同时包含进度与“查看”按钮的最小容器
       let container = node;

       for (let i = 0; i < 8 && container; i++) {
         const controls = [
           ...container.querySelectorAll(
             'button, a, [role="button"]'
           )
         ];

         const hasView = controls.some(el =>
           visible(el) && /查看/.test(textOf(el))
         );

         const hasProgress = /学习进度/.test(textOf(container));

         if (hasView && hasProgress) break;

         container = container.parentElement;
       }

       if (!container || seen.has(container)) continue;

       const viewButton = [
         ...container.querySelectorAll(
           'button, a, [role="button"]'
         )
       ].find(el =>
         visible(el) && /查看/.test(textOf(el))
       );

       if (!viewButton) continue;

       seen.add(container);

       lessons.push({
         container,
         viewButton,
         progress,
         title: textOf(container).slice(0, 100)
       });
     }

     // 按页面从上到下排列
     lessons.sort((a, b) =>
       a.container.getBoundingClientRect().top -
       b.container.getBoundingClientRect().top
     );

     return lessons[0] || null;
   }

   // 在列表页定位下一节未完成的课件
   function locateNext() {
     const lesson = findIncompleteLesson();

     if (!lesson) {
       status.textContent = '未找到可识别的未完成课件';
       result.textContent =
         '请确认当前是课程列表页，并且进度文字为“学习进度：xx%”。';
       return;
     }

     lesson.container.scrollIntoView({
       behavior: 'smooth',
       block: 'center'
     });

     lesson.container.style.outline = '3px solid #8877ff';
     lesson.container.style.outlineOffset = '3px';

     status.textContent =
       `找到下一节候选课件：${lesson.progress}%`;

     result.textContent =
       '已定位到未完成课件。请核对课件名称，再点击该课件右侧的“查看”。';

     log('候选课件', lesson.title, lesson.progress + '%');
   }

   // 返回课程活动列表
   function returnToList() {
     const button = findVisibleControl(/返回课堂活动列表/);

     if (button) {
       button.click();
       result.textContent = '已尝试返回课程活动列表。';
       return;
     }

     result.textContent =
       '当前页面未找到“返回课堂活动列表”按钮，请手动返回列表。';
   }

   panel.querySelector('#zj-locate')
     .addEventListener('click', locateNext);

   panel.querySelector('#zj-return')
     .addEventListener('click', returnToList);

   // 检查当前页面是否有视频
   const videos = [...document.querySelectorAll('video')];

   if (videos.length) {
     status.textContent = '已检测到视频播放器';

     videos.forEach(video => {
       video.addEventListener('ended', () => {
         status.textContent = '视频播放结束';

         result.textContent =
           '请确认学习记录已保存，再点击“返回列表”，定位下一节。';

         log('检测到视频 ended 事件');
       });
     });
   } else {
     status.textContent = '辅助面板已启动';
   }

   log('初始化完成', location.href);
 })();