feat(前台): 各页直达后台对应功能——编辑这一课、新建比赛、编辑这条公告……

题目页「编辑题目」从只给超管放宽到有权改这道题的人（含学生管理员改自己出的题）；
题目、比赛、题单列表加「新建」；自学首页加「自学情况」「管理教程」，课文加「编辑这一课」；
公告加「编辑这条」「发公告」；成就加「管理成就」；智能分析加「AI 报告」，看某个学生时
带着用户名过去直接筛到他。按钮统一走 shared/components/AdminLink.vue。

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/api/src/auth/presence.ts

@@ -1,6 +1,7 @@
 import type { ChainableCommander } from "ioredis"
 
 import { redis } from "../redis"
+import { calendarDay } from "../time"
 
 /**
  * 「谁现在在线」。member = userId，score = 最后一次活动的毫秒时间戳。
@@ -18,9 +19,24 @@ const PRESENCE_KEY = "online-users"
  */
 const ONLINE_WINDOW_MS = 5 * 60 * 1000
 
+/**
+ * 「今天谁上过线、最后一次是几点」，一天一个 key，同样是 userId → 毫秒时间戳。
+ *
+ * 课堂看板拿它判断谁今天没来：机房有两人共用一台电脑的，同一时刻只有一个人登着，
+ * 只看「此刻在不在线」会把坐在旁边的同桌当成没来。上过线的人不管现在登没登着都算来过。
+ * 上面那张会被修剪到最近 5 分钟，留不住这个，所以单记一张，放两天自己过期。
+ */
+const seenTodayKey = (day: string) => `online-users:${day}`
+const SEEN_TODAY_TTL_SECONDS = 2 * 24 * 60 * 60
+
 /** 记一笔活动。传 pipeline 而不是自己发命令：调用点都在热路径上 */
 export function markOnline(pipeline: ChainableCommander, userId: number) {
-  pipeline.zadd(PRESENCE_KEY, Date.now(), String(userId))
+  const now = Date.now()
+  const seenKey = seenTodayKey(calendarDay(now))
+  pipeline
+    .zadd(PRESENCE_KEY, now, String(userId))
+    .zadd(seenKey, now, String(userId))
+    .expire(seenKey, SEEN_TODAY_TTL_SECONDS)
 }
 
 /**
@@ -51,3 +67,21 @@ export async function isUserOnline(userId: number) {
   const score = await redis.zscore(PRESENCE_KEY, String(userId))
   return score !== null && Number(score) >= Date.now() - ONLINE_WINDOW_MS
 }
+
+/**
+ * 这批人今天最后一次上线的时刻（毫秒），今天没上过线的不在结果里。
+ * `online` 和 onlineUserIds 同一个窗口
+ */
+export async function seenToday(userIds: number[]) {
+  const seen = new Map<number, { at: number; online: boolean }>()
+  if (!userIds.length) return seen
+  const scores = await redis.zmscore(seenTodayKey(calendarDay()), ...userIds.map(String))
+  const cutoff = Date.now() - ONLINE_WINDOW_MS
+  userIds.forEach((userId, i) => {
+    const score = scores[i]
+    if (score === null || score === undefined) return
+    const at = Number(score)
+    seen.set(userId, { at, online: at >= cutoff })
+  })
+  return seen
+}

apps/api/src/routes/classroom.ts

@@ -17,6 +17,7 @@ import { and, asc, desc, eq, gte, inArray, isNotNull, isNull, lt, sql } from "dr
 import { Hono } from "hono"
 
 import { requireAuth, requireTeacher, type AppEnv } from "../auth/middleware"
+import { seenToday } from "../auth/presence"
 import { getLoginWindow } from "../auth/session"
 import { presenceOf } from "../collab/state"
 import { db, schema } from "../db"
@@ -568,7 +569,7 @@ classroomRoutes.get("/classroom/board", requireTeacher, async (c) => {
   // 「来了几次」代码和流程图合起来数：那天只画了流程图的也算来过，和 recentDays 同一个口径
   const recentActivity = activityRows({ since: windowStart, users: userIds })
   const localDay = sql<string>`to_char(${localTime(recentActivity.createTime)}, 'YYYY-MM-DD')`
-  const [cells, lastSubmits, lastDrawn, attendance, drawn, latests] = await Promise.all([
+  const [cells, lastSubmits, lastDrawn, attendance, drawn, latests, seen] = await Promise.all([
     ids.length && userIds.length
       ? db
           .select({
@@ -694,6 +695,7 @@ classroomRoutes.get("/classroom/board", requireTeacher, async (c) => {
             desc(schema.submission.createTime),
           )
       : [],
+    seenToday(userIds),
   ])
   const latestByKey = new Map(latests.map((row) => [`${row.userId}:${row.problemId}`, row]))
   const cellByKey = new Map(cells.map((row) => [`${row.userId}:${row.problemId}`, row]))
@@ -757,6 +759,10 @@ classroomRoutes.get("/classroom/board", requireTeacher, async (c) => {
           drawnToday: drawnTodayUsers.has(student.userId),
           recentAttended: attendedByUser.get(student.userId) ?? 0,
           editing: presenceOf(student.userId)?.problemId ?? null,
+          online: seen.get(student.userId)?.online ?? false,
+          seenAt: seen.has(student.userId)
+            ? new Date(seen.get(student.userId)!.at).toISOString()
+            : null,
         }) satisfies ClassBoardStudent,
     ),
     recentLessons: recentDays.length,

apps/web/src/admin/ai/list.vue

@@ -21,7 +21,13 @@ const theme = useThemeVars()
 
 const reports = ref<AdminAiReportListItem[]>([])
 const total = ref(0)
-const query = reactive({ limit: 10, page: 1, username: "" })
+// 前台「智能分析」看某个学生时的「AI 报告」按钮带着 ?username= 过来，直接筛到他
+const route = useRoute()
+const query = reactive({
+  limit: 10,
+  page: 1,
+  username: typeof route.query.username === "string" ? route.query.username : "",
+})
 
 const selectedId = ref<number | null>(null)
 const detail = ref<AdminAiReport | null>(null)

apps/web/src/oj/achievement/index.vue

@@ -4,6 +4,7 @@ import { getAchievements } from "oj/achievement/api"
 import { getUserBadges } from "oj/api"
 import { useBreakpoints } from "shared/composables/breakpoints"
 import UserName from "shared/components/UserName.vue"
+import AdminLink from "shared/components/AdminLink.vue"
 import { useUserStore } from "shared/store/user"
 import { RARITY_COLOR, RARITY_LABEL } from "utils/constants"
 import type { AchievementList, AchievementRarity, UserBadge } from "utils/types"
@@ -83,6 +84,9 @@ watch(name, load)
             </span>
           </span>
           <router-link v-if="other" to="/achievement" class="mine">看我的 ›</router-link>
+          <div v-if="userStore.isSuperAdmin && isDesktop" class="admin-link">
+            <AdminLink to="/admin/achievement/list" size="small">管理成就</AdminLink>
+          </div>
         </div>
 
         <!-- 没有班级（老师、自己注册的号）就没有「本班」，「快拿到了」三个横排占满整宽 -->
@@ -168,6 +172,16 @@ h2 {
   font-variant-numeric: tabular-nums;
 }
 
+/* 两个都在时「看我的」占着 auto，按钮跟在它后面 */
+.admin-link {
+  margin-left: auto;
+  align-self: center;
+}
+
+.mine + .admin-link {
+  margin-left: 0;
+}
+
 .mine {
   margin-left: auto;
   font-size: var(--oj-fs-sec);

apps/web/src/oj/ai/analysis.vue

@@ -8,6 +8,7 @@ import {
 import { useRouteQuery } from "@vueuse/router"
 import { useThemeVars } from "naive-ui"
 import { useBreakpoints } from "shared/composables/breakpoints"
+import AdminLink from "shared/components/AdminLink.vue"
 import { useUserStore } from "shared/store/user"
 import UserName from "shared/components/UserName.vue"
 import { classLabel } from "oj/submission/utils"
@@ -137,6 +138,13 @@ function goStudent(username: string | null | undefined) {
       >
         看<UserName :username="viewing" />的提交 ›
       </router-link>
+      <AdminLink
+        v-if="userStore.isTeacherOrAbove && isDesktop"
+        :to="{ path: '/admin/ai/reports', query: viewing ? { username: viewing } : {} }"
+        size="small"
+      >
+        AI 报告
+      </AdminLink>
     </div>
 
     <n-spin :show="loading" :delay="150">

apps/web/src/oj/announcement/list.vue

@@ -1,8 +1,10 @@
 <script setup lang="ts">
 import { useThemeVars } from "naive-ui"
 import { getAnnouncement, getAnnouncementList } from "oj/api"
+import AdminLink from "shared/components/AdminLink.vue"
 import NotFound from "shared/components/NotFound.vue"
 import { useBreakpoints } from "shared/composables/breakpoints"
+import { useUserStore } from "shared/store/user"
 import { errorCode } from "utils/api"
 import { parseTime, zonedParts, zonedYear } from "utils/functions"
 import type { Announcement, AnnouncementListItem } from "utils/types"
@@ -19,6 +21,7 @@ const LIMIT = 100
 const theme = useThemeVars()
 const route = useRoute()
 const router = useRouter()
+const userStore = useUserStore()
 const { isDesktop } = useBreakpoints()
 
 const announcements = ref<AnnouncementListItem[]>([])
@@ -105,7 +108,19 @@ const showReader = computed(() => isDesktop.value || queryId.value !== null)
 
 <template>
   <div class="page oj-page">
-    <h2>公告</h2>
+    <div class="head">
+      <h2>公告</h2>
+      <template v-if="userStore.isSuperAdmin">
+        <span class="grow"></span>
+        <AdminLink
+          v-if="showReader && detail"
+          :to="{ name: 'admin announcement edit', params: { announcementID: detail.id } }"
+        >
+          编辑这条
+        </AdminLink>
+        <AdminLink to="/admin/announcement/create">发公告</AdminLink>
+      </template>
+    </div>
 
     <n-empty v-if="loaded && !announcements.length" description="还没有公告" class="blank" />
 
@@ -177,6 +192,16 @@ h2 {
   font-size: var(--oj-fs-title);
 }
 
+.head {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+}
+
+.grow {
+  flex-grow: 1;
+}
+
 .blank {
   margin-top: 60px;
 }

apps/web/src/oj/classroom/board.vue

@@ -189,6 +189,20 @@ function oftenIdle(student: ClassBoardStudent) {
   return total >= 3 && student.recentAttended <= 1
 }
 
+/**
+ * 今天一次都没上过线。机房有两人共用一台电脑的，同桌只有一个登着，所以「谁没来」
+ * 看今天上没上过线，不看此刻在不在线（见契约 seenAt）
+ */
+function unseen(student: ClassBoardStudent) {
+  return !student.seenAt
+}
+
+/** 没在线的人最后一次上线是多久前，「在写」那格用 */
+function seenText(seenAt: string) {
+  const minutes = Math.max(0, Math.floor((now.value.getTime() - Date.parse(seenAt)) / 60_000))
+  return minutes < 60 ? `${minutes} 分钟前在` : `${Math.floor(minutes / 60)} 小时前在`
+}
+
 function doneCount(student: ClassBoardStudent) {
   return student.cells.filter((cell) => cell.status === "accepted").length
 }
@@ -251,7 +265,22 @@ watchEffect(() => {
 const leaveDialog = ref(false)
 /** 弹框里能勾的：今天还没交过的（刚上课时就是全班），按名字排 */
 const leaveCandidates = computed(() => boardStudents.value.filter(canLeave).sort(byName))
+/** 今天没上过线的分在前面一堆：请假的人基本在这里面，剩下的是和同桌共用电脑的 */
+const leaveSections = computed(() =>
+  [
+    { label: "今天没上线", students: leaveCandidates.value.filter(unseen) },
+    {
+      label: "今天上过线",
+      students: leaveCandidates.value.filter((student) => !unseen(student)),
+    },
+  ].filter((section) => section.students.length),
+)
 const leaveSelected = ref<string[]>([])
+function selectAll(list: ClassBoardStudent[]) {
+  leaveSelected.value = [
+    ...new Set([...leaveSelected.value, ...list.map((student) => student.username)]),
+  ]
+}
 function openLeaveDialog() {
   leaveSelected.value = leaveStudents.value.map((student) => student.username)
   leaveDialog.value = true
@@ -272,7 +301,8 @@ const students = computed(() =>
   [...boardStudents.value].sort(
     (a, b) =>
       GROUP_ORDER[groupOf(a)] - GROUP_ORDER[groupOf(b)] ||
-      // 同样是没交过，经常不动手的排前面
+      // 同样是没交过，今天没上过线的排最前（多半没来，好标请假），再是经常不动手的
+      Number(unseen(b)) - Number(unseen(a)) ||
       Number(oftenIdle(b)) - Number(oftenIdle(a)) ||
       // 同样在做，做对得少的排前面（只做了一道的那几个）
       (groupOf(a) === "working" ? doneCount(a) - doneCount(b) : 0) ||
@@ -679,7 +709,7 @@ function shortTitle(title: string, size: number) {
           <thead>
             <tr>
               <th class="name">学生</th>
-              <th class="narrow-col where-col">在写</th>
+              <th class="narrow-col where-col">在线</th>
               <th
                 v-for="(stat, i) in problemStats"
                 :key="stat.problem.problemId"
@@ -728,8 +758,9 @@ function shortTitle(title: string, size: number) {
                     举手 {{ waitedText(helpOf(student)!.createdAt) }}
                   </span>
                 </td>
-                <!-- 在写：举手的「帮他」；别人在帮的写谁在帮；开着题目的点题号直接打开他正在写的
-                     代码（他没举手也行，他那边会显示「xxx 在看你的代码」） -->
+                <!-- 在线：举手的「帮他」；别人在帮的写谁在帮；开着题目的点题号直接打开他正在写的
+                     代码（他没举手也行，他那边会显示「xxx 在看你的代码」）；剩下的写在不在线、
+                     多久前在、今天没上过线 -->
                 <td class="where-col">
                   <n-button
                     v-if="helpOf(student)?.status === 'pending'"
@@ -751,7 +782,11 @@ function shortTitle(title: string, size: number) {
                   >
                     {{ student.editing }}
                   </button>
-                  <span v-else class="muted">—</span>
+                  <span v-else-if="student.online" class="present">在线</span>
+                  <span v-else-if="student.seenAt" class="seen">
+                    {{ seenText(student.seenAt) }}
+                  </span>
+                  <span v-else class="seen">今天没上线</span>
                 </td>
                 <td
                   v-for="(cell, i) in student.cells"
@@ -814,14 +849,30 @@ function shortTitle(title: string, size: number) {
       style="width: 640px; max-width: calc(100vw - 32px)"
     >
       <n-checkbox-group v-if="leaveCandidates.length" v-model:value="leaveSelected">
-        <div class="leave-grid">
-          <n-checkbox
-            v-for="student in leaveCandidates"
-            :key="student.userId"
-            :value="student.username"
-            :label="student.username"
-            class="leave-option"
-          />
+        <div v-for="section in leaveSections" :key="section.label" class="leave-section">
+          <div v-if="leaveSections.length > 1 || unseen(section.students[0])" class="leave-head">
+            {{ section.label }} {{ section.students.length }} 人
+            <n-button
+              v-if="unseen(section.students[0])"
+              text
+              type="primary"
+              :disabled="
+                section.students.every((student) => leaveSelected.includes(student.username))
+              "
+              @click="selectAll(section.students)"
+            >
+              全勾上
+            </n-button>
+          </div>
+          <div class="leave-grid">
+            <n-checkbox
+              v-for="student in section.students"
+              :key="student.userId"
+              :value="student.username"
+              :label="student.username"
+              class="leave-option"
+            />
+          </div>
         </div>
       </n-checkbox-group>
       <n-text v-else depth="3">请假的人一定是没交过题的，现在没有人可以标。</n-text>
@@ -1305,7 +1356,22 @@ a.cell {
   cursor: pointer;
 }
 
-.where::before {
+.present {
+  display: inline-flex;
+  align-items: center;
+  gap: 5px;
+  font-size: 13px;
+  color: v-bind("tone('success').color");
+}
+
+.seen {
+  font-size: 13px;
+  white-space: nowrap;
+  color: v-bind("theme.textColor3");
+}
+
+.where::before,
+.present::before {
   content: "";
   width: 7px;
   height: 7px;
@@ -1323,6 +1389,18 @@ a.cell {
   color: v-bind("tone('info').color");
 }
 
+.leave-section + .leave-section {
+  margin-top: 18px;
+}
+
+.leave-head {
+  display: flex;
+  align-items: center;
+  gap: 12px;
+  margin-bottom: 10px;
+  font-weight: 600;
+}
+
 .leave-grid {
   display: grid;
   grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));

apps/web/src/oj/contest/list.vue

@@ -9,6 +9,8 @@ import ContestTitle from "shared/components/ContestTitle.vue"
 import Pagination from "shared/components/Pagination.vue"
 import { useAuthModalStore } from "shared/store/authModal"
 import { usePagination } from "shared/composables/pagination"
+import AdminLink from "shared/components/AdminLink.vue"
+import { useBreakpoints } from "shared/composables/breakpoints"
 import { useUserStore } from "shared/store/user"
 import { ContestStatus } from "utils/constants"
 import ContestBadge from "./components/ContestBadge.vue"
@@ -19,6 +21,7 @@ import ContestBadge from "./components/ContestBadge.vue"
  */
 const router = useRouter()
 const userStore = useUserStore()
+const { isDesktop } = useBreakpoints()
 const authStore = useAuthModalStore()
 const theme = useThemeVars()
 const tone = useTone()
@@ -145,6 +148,10 @@ const warning = computed(() => tone("warning"))
         {{ item.label }}
       </button>
       <n-input v-model:value="query.keyword" clearable placeholder="比赛名" style="width: 200px" />
+      <!-- 手机上一行放不下，也没人在手机上出题，只给电脑 -->
+      <AdminLink v-if="isDesktop && userStore.isTeacherOrAbove" to="/admin/contest/create"
+        >新建比赛</AdminLink
+      >
     </div>
 
     <div

apps/web/src/oj/learn/components/CodeRunBlock.vue

@@ -10,8 +10,6 @@ import { explainRuntimeError } from "oj/problem/utils/runtimeError"
 import { useAuthModalStore } from "shared/store/authModal"
 import { useUserStore } from "shared/store/user"
 import { mainWrapExtensions, wrapMain } from "../wrapMain"
-import { hangWrapExtensions } from "shared/extensions/hangIndent"
-import { useBreakpoints } from "shared/composables/breakpoints"
 
 const CodeEditor = defineAsyncComponent(() => import("shared/components/CodeEditor.vue"))
 
@@ -37,12 +35,8 @@ const message = useMessage()
 const { copy } = useClipboard({ legacy: true })
 
 const original = computed(() => (props.wrapMain ? wrapMain(props.code) : props.code))
-const { isDesktop } = useBreakpoints()
-// 手机上折行（见 hangIndent.ts）；桌面正文 720 宽，长行少，照旧横着滚
-const extensions = computed(() => [
-  ...(props.wrapMain ? mainWrapExtensions : []),
-  ...(isDesktop.value ? [] : hangWrapExtensions),
-])
+// 手机上也不折行，长行横着滚：折下来的那截看着像另起了一行代码
+const extensions = computed(() => (props.wrapMain ? mainWrapExtensions : []))
 const value = ref(original.value)
 const input = ref("")
 const running = ref(false)

apps/web/src/oj/learn/components/ExerciseDebug.vue

@@ -2,7 +2,6 @@
 import ExerciseResult from "./ExerciseResult.vue"
 import type { Exercise, ExerciseDebugData } from "utils/types"
 import { highlightLines } from "shared/highlight"
-import { hangStyle } from "shared/extensions/hangIndent"
 
 const props = defineProps<{ exercise: Exercise; lang?: string }>()
 const emit = defineEmits<{
@@ -92,19 +91,19 @@ function reset() {
       点击你认为有错误的代码行（可多选）。
     </p>
 
-    <n-space vertical :size="6">
+    <!-- 不折行：长行整组一起横着滚，每行一样宽（= 最长那行），和正文的代码块一样 -->
+    <div style="overflow-x: auto">
       <div
-        v-for="(line, idx) in data.lines"
-        :key="idx"
-        :style="lineStyle(idx)"
-        @click="toggle(idx)"
+        style="display: flex; flex-direction: column; gap: 6px; width: max-content; min-width: 100%"
       >
-        <span style="color: #bbb; width: 22px; text-align: right; flex-shrink: 0">
-          {{ idx + 1 }}
-        </span>
-        <span v-html="lineHtml[idx]" :style="{ minWidth: 0, ...hangStyle(line) }" />
+        <div v-for="(_, idx) in data.lines" :key="idx" :style="lineStyle(idx)" @click="toggle(idx)">
+          <span style="color: #bbb; width: 22px; text-align: right; flex-shrink: 0">
+            {{ idx + 1 }}
+          </span>
+          <span v-html="lineHtml[idx]" style="white-space: pre" />
+        </div>
       </div>
-    </n-space>
+    </div>
 
     <ExerciseResult
       v-if="submitted"

apps/web/src/oj/learn/components/ExerciseFill.vue

@@ -2,7 +2,6 @@
 import ExerciseResult from "./ExerciseResult.vue"
 import type { Exercise, ExerciseFillData } from "utils/types"
 import { highlightWithHoles } from "shared/highlight"
-import { hangStyle } from "shared/extensions/hangIndent"
 
 const props = defineProps<{ exercise: Exercise; lang?: string }>()
 const emit = defineEmits<{
@@ -39,28 +38,21 @@ const segments = computed<Segment[]>(() => {
 })
 
 /**
- * 按行切开，每行自己折行、悬挂缩进（见 hangIndent.ts）。原来整段 pre-wrap，
- * 手机上行尾的注释折下来顶格，看着像另起了一行代码。
+ * 按行切开，一行一个块；不折行，长行整块横着滚（和正文的代码块一样）。
  * 高亮的 HTML 在换行处是断开的（见 shared/highlight.ts 的 walk），按 "\n" 切不会切坏标签。
  */
 const lines = computed(() => {
-  const rows: { indent: string; parts: Segment[] }[] = [{ indent: "", parts: [] }]
+  const rows: { parts: Segment[] }[] = [{ parts: [] }]
   for (const seg of segments.value) {
     if (seg.type === "blank") {
       rows[rows.length - 1].parts.push(seg)
       continue
     }
     seg.html.split("\n").forEach((html, i) => {
-      if (i > 0) rows.push({ indent: "", parts: [] })
+      if (i > 0) rows.push({ parts: [] })
       if (html) rows[rows.length - 1].parts.push({ type: "code", html })
     })
   }
-  for (const row of rows) {
-    const first = row.parts[0]
-    if (first?.type === "code") {
-      row.indent = first.html.replace(/<[^>]*>/g, "").match(/^[ \t]*/)![0]
-    }
-  }
   return rows
 })
 
@@ -114,13 +106,10 @@ function inputWidth(idx: number): string {
         border: '1px solid var(--learn-line)',
         borderRadius: '6px',
         padding: '10px 12px',
+        overflowX: 'auto',
       }"
     >
-      <div
-        v-for="(row, r) in lines"
-        :key="r"
-        :style="{ minHeight: '1.9em', ...hangStyle(row.indent) }"
-      >
+      <div v-for="(row, r) in lines" :key="r" style="min-height: 1.9em; white-space: pre">
         <template v-for="(seg, i) in row.parts" :key="i"
           ><span v-if="seg.type === 'code'" v-html="seg.html" /><input
             v-else
@@ -136,7 +125,6 @@ function inputWidth(idx: number): string {
               fontSize: '16px',
               lineHeight: '1.4',
               padding: '2px 6px',
-              textIndent: 0,
               borderRadius: '4px',
               border: `1.5px solid ${
                 allCorrect

apps/web/src/oj/learn/components/ExerciseSort.vue

@@ -4,7 +4,6 @@ import type { Exercise, ExerciseSortData } from "utils/types"
 import { shuffle } from "../composables/useShuffle"
 import { highlightLines } from "shared/highlight"
 import { useBreakpoints } from "shared/composables/breakpoints"
-import { hangStyle } from "shared/extensions/hangIndent"
 
 const props = defineProps<{ exercise: Exercise; lang?: string }>()
 const emit = defineEmits<{
@@ -100,51 +99,53 @@ const lineHtml = computed<string[]>(() => highlightLines(data.value.lines, props
       先点一行，再点它该去的位置。
     </p>
 
-    <n-space vertical :size="6">
+    <!-- 不折行：长行整组一起横着滚，每行一样宽（= 最长那行），和正文的代码块一样 -->
+    <div style="overflow-x: auto">
       <div
-        v-for="(line, idx) in lines"
-        :key="line.originalIdx"
-        draggable="true"
-        :style="{
-          display: 'flex',
-          alignItems: 'center',
-          gap: '10px',
-          padding: '8px 12px',
-          borderRadius: '6px',
-          border:
-            pickedIdx === idx
-              ? '2px solid #2080f0'
-              : `1.5px ${submitted ? 'solid' : 'dashed'} ${
-                  lineStatus(idx) === 'correct'
-                    ? '#18a058'
-                    : lineStatus(idx) === 'wrong'
-                      ? '#d03050'
-                      : 'var(--learn-control-line)'
-                }`,
-          background:
-            pickedIdx === idx
-              ? 'rgba(32,128,240,0.08)'
-              : lineStatus(idx) === 'correct'
-                ? 'rgba(24,160,88,0.08)'
-                : lineStatus(idx) === 'wrong'
-                  ? 'rgba(208,48,80,0.07)'
-                  : 'transparent',
-          cursor: 'grab',
-          fontFamily: 'var(--learn-code-font)',
-          userSelect: 'none',
-        }"
-        @dragstart="onDragStart(idx)"
-        @dragover.prevent
-        @drop="onDrop(idx)"
-        @click="onLineClick(idx)"
+        style="display: flex; flex-direction: column; gap: 6px; width: max-content; min-width: 100%"
       >
-        <span style="color: #bbb; cursor: grab">⠿</span>
-        <span
-          v-html="lineHtml[line.originalIdx]"
-          :style="{ minWidth: 0, ...hangStyle(line.text) }"
-        />
+        <div
+          v-for="(line, idx) in lines"
+          :key="line.originalIdx"
+          draggable="true"
+          :style="{
+            display: 'flex',
+            alignItems: 'center',
+            gap: '10px',
+            padding: '8px 12px',
+            borderRadius: '6px',
+            border:
+              pickedIdx === idx
+                ? '2px solid #2080f0'
+                : `1.5px ${submitted ? 'solid' : 'dashed'} ${
+                    lineStatus(idx) === 'correct'
+                      ? '#18a058'
+                      : lineStatus(idx) === 'wrong'
+                        ? '#d03050'
+                        : 'var(--learn-control-line)'
+                  }`,
+            background:
+              pickedIdx === idx
+                ? 'rgba(32,128,240,0.08)'
+                : lineStatus(idx) === 'correct'
+                  ? 'rgba(24,160,88,0.08)'
+                  : lineStatus(idx) === 'wrong'
+                    ? 'rgba(208,48,80,0.07)'
+                    : 'transparent',
+            cursor: 'grab',
+            fontFamily: 'var(--learn-code-font)',
+            userSelect: 'none',
+          }"
+          @dragstart="onDragStart(idx)"
+          @dragover.prevent
+          @drop="onDrop(idx)"
+          @click="onLineClick(idx)"
+        >
+          <span style="color: #bbb; cursor: grab">⠿</span>
+          <span v-html="lineHtml[line.originalIdx]" style="white-space: pre" />
+        </div>
       </div>
-    </n-space>
+    </div>
 
     <ExerciseResult
       v-if="submitted"

apps/web/src/oj/learn/home.vue

@@ -4,6 +4,7 @@ import type { TutorialProgress, TutorialSummary } from "@oj2/contract"
 import { getLearnProgress, getTutorials } from "../api"
 import { useBreakpoints } from "shared/composables/breakpoints"
 import { useAuthModalStore } from "shared/store/authModal"
+import AdminLink from "shared/components/AdminLink.vue"
 import { useUserStore } from "shared/store/user"
 import {
   COURSES,
@@ -251,6 +252,16 @@ onMounted(load)
         >
           登录后记下学到哪
         </button>
+        <div v-if="isDesktop && userStore.isTeacherOrAbove" class="admin-links">
+          <AdminLink to="/admin/learn" size="small">自学情况</AdminLink>
+          <AdminLink
+            v-if="userStore.isSuperAdmin"
+            :to="{ path: '/admin/tutorial/list', query: { type: tab } }"
+            size="small"
+          >
+            管理教程
+          </AdminLink>
+        </div>
       </div>
 
       <div v-if="current && isDesktop" class="map">
@@ -483,6 +494,11 @@ onMounted(load)
   font-weight: 400;
   opacity: 0.6;
 }
+.admin-links {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+}
 .login {
   border: 0;
   background: transparent;

apps/web/src/oj/learn/index.vue

@@ -8,6 +8,7 @@ import { parseLesson } from "./composables/useLessonParse"
 import { useLearnTrace } from "./composables/useLearnTrace"
 import { useBackClose } from "shared/composables/backClose"
 import { useBreakpoints } from "shared/composables/breakpoints"
+import AdminLink from "shared/components/AdminLink.vue"
 import { useUserStore } from "shared/store/user"
 import {
   COURSES,
@@ -293,6 +294,15 @@ function jumpExercise(id: number) {
               <span v-if="tutorial.project">{{ tutorial.project }}</span>
               <span v-if="tutorial.project">·</span>
               <span class="num">第 {{ step }} / {{ titles.length }} 课</span>
+              <template v-if="userStore.isSuperAdmin">
+                <span class="grow" />
+                <AdminLink
+                  :to="{ name: 'admin tutorial edit', params: { tutorialID: tutorial.id } }"
+                  size="tiny"
+                >
+                  编辑这一课
+                </AdminLink>
+              </template>
             </div>
             <h1 class="h1">{{ parts.kp }}</h1>
             <div v-if="parts.scene" class="scene">{{ parts.scene }}</div>
@@ -546,6 +556,7 @@ function jumpExercise(id: number) {
 }
 .crumb {
   display: flex;
+  align-items: center;
   gap: 8px;
   font-size: 13px;
   margin-bottom: 6px;

apps/web/src/oj/problem/composables/editorMenu.ts

@@ -58,7 +58,8 @@ export function useEditorMenu(statisticsInline: Ref<boolean>) {
       // 一写回去就顺着 Yjs 同步过去，等于一键清空学生的作业，他还没法撤回
       if (!teacherCollab.value) items.push({ label: "重置代码", key: "reset" })
     }
-    if (isDesktop.value && userStore.isSuperAdmin) items.push({ label: "编辑题目", key: "edit" })
+    if (isDesktop.value && problem.value && userStore.canEditProblem(problem.value))
+      items.push({ label: "编辑题目", key: "edit" })
     return items
   })
 

apps/web/src/oj/problem/list.vue

@@ -15,6 +15,7 @@ import Pagination from "shared/components/Pagination.vue"
 import { useBreakpoints } from "shared/composables/breakpoints"
 import { usePagination } from "shared/composables/pagination"
 import { useAuthModalStore } from "shared/store/authModal"
+import AdminLink from "shared/components/AdminLink.vue"
 import { useUserStore } from "shared/store/user"
 import ProblemStatus from "./components/ProblemStatus.vue"
 import ProblemTypeTag from "./components/ProblemTypeTag.vue"
@@ -430,6 +431,9 @@ const gridColumns = computed(() =>
           </div>
           <div class="spacer"></div>
           <Hitokoto class="hitokoto" />
+          <AdminLink v-if="userStore.hasProblemPermission" to="/admin/problem/create" size="small">
+            新建题目
+          </AdminLink>
         </div>
 
         <div class="titlebar">

apps/web/src/oj/problemset/list.vue

@@ -1,5 +1,8 @@
 <script setup lang="ts">
 import { useThemeVars } from "naive-ui"
+import AdminLink from "shared/components/AdminLink.vue"
+import { useBreakpoints } from "shared/composables/breakpoints"
+import { useUserStore } from "shared/store/user"
 import { getProblemSetList } from "oj/api"
 import { rgba, useTone } from "oj/submission/composables/tone"
 import { parseTime } from "utils/functions"
@@ -13,6 +16,8 @@ import { badgeCondition, ladder, nextBadge } from "./badges"
  * 题单一共十几个，一次全取回来在前端分组，不分页
  */
 const router = useRouter()
+const userStore = useUserStore()
+const { isDesktop } = useBreakpoints()
 const theme = useThemeVars()
 const tone = useTone()
 
@@ -88,6 +93,10 @@ const doneBackground = computed(() => rgba(theme.value.successColor, 0.05))
       <h2>题单</h2>
       <div class="spacer"></div>
       <n-input v-model:value="keyword" placeholder="搜题单" clearable class="search" />
+      <!-- 手机上一行放不下，也没人在手机上出题，只给电脑 -->
+      <AdminLink v-if="isDesktop && userStore.isTeacherOrAbove" to="/admin/problemset/create"
+        >新建题单</AdminLink
+      >
     </div>
 
     <template v-if="assigning.length">

apps/web/src/shared/components/AdminLink.vue

@@ -0,0 +1,19 @@
+<script setup lang="ts">
+import { RouterLink, type RouteLocationRaw } from "vue-router"
+
+/**
+ * 前台页面上直达后台对应功能的按钮（「编辑这一课」「新建比赛」……），和题单页的
+ * 「编辑题单」、比赛页的「比赛设置」同一种样子。渲染成真的 <a>：老师常要一边看前台
+ * 一边改，中键 / Ctrl 点开新标签页得能用。给谁看由调用方用 v-if 管，要和
+ * routes.ts 里目标路由的 meta 对齐，否则点下去被守卫静默踢回首页。
+ */
+withDefaults(defineProps<{ to: RouteLocationRaw; size?: "tiny" | "small" | "medium" }>(), {
+  size: "medium",
+})
+</script>
+
+<template>
+  <RouterLink v-slot="{ href, navigate }" :to="to" custom>
+    <n-button tag="a" :href="href" :size="size" @click="navigate"><slot /></n-button>
+  </RouterLink>
+</template>

apps/web/src/shared/extensions/hangIndent.ts

@@ -8,9 +8,9 @@ import {
 } from "@codemirror/view"
 
 /**
- * 手机上代码折行（自学的代码块和练一练、题目页的编辑器）。原来是横着滚，可没有滚动条
- * 也看不出右边还有，自学综合练习那种长 print 整整半行看不见。折下来的那截缩到这一行的
- * 代码下面再进两格，一眼看得出还是同一行。
+ * 手机上代码折行（题目页的编辑器）。原来是横着滚，可没有滚动条也看不出右边还有。
+ * 折下来的那截缩到这一行的代码下面再进两格，一眼看得出还是同一行。
+ * 自学的代码块和练一练也这么折过，用户嫌不好看，又改回横着滚了。
  */
 
 /** 行首空白占几格，tab 按 4 */
@@ -24,19 +24,6 @@ function leadingWidth(text: string): number {
   return width
 }
 
-/** 静态的代码行（练一练的排序、找错、填空）：折行，接着的那截悬挂缩进 */
-export function hangStyle(text: string): Record<string, string> {
-  const width = leadingWidth(text) + 2
-  return {
-    whiteSpace: "pre-wrap",
-    // 中文连着的一串别从中间断（「类」「型」各在一行），实在放不下才随便断
-    wordBreak: "keep-all",
-    overflowWrap: "anywhere",
-    paddingLeft: `${width}ch`,
-    textIndent: `-${width}ch`,
-  }
-}
-
 const glue = Decoration.mark({ attributes: { style: "white-space: nowrap" } })
 
 function hangDecorations(view: EditorView): DecorationSet {
@@ -82,5 +69,5 @@ const hangPlugin = ViewPlugin.fromClass(
   { decorations: (plugin) => plugin.decorations },
 )
 
-/** 编辑器（正文里能运行的代码块）：折行 + 悬挂缩进 */
+/** 编辑器：折行 + 悬挂缩进 */
 export const hangWrapExtensions = [EditorView.lineWrapping, hangPlugin]

apps/web/src/shared/store/user.ts

@@ -49,6 +49,22 @@ export const useUserStore = defineStore("user", () => {
 
   const canToggleDemoMode = computed(() => realIsSuperAdmin.value)
 
+  /**
+   * 前台「编辑题目」入口给谁看，对齐后端 admin/problem.ts 的 canEdit：
+   * 公开题看题目的创建者（或题目权限是「全部」），比赛题看比赛的创建者。
+   * 题目页拿不到比赛的创建者，比赛题就按题目的创建者估 —— 比赛题基本是出题老师
+   * 自己建或克隆的；估错了后台会拦，只是多一个点进去 404 的入口。
+   */
+  function canEditProblem(problem: { contestId: number | null; createdBy: { id: number } }) {
+    if (isSuperAdmin.value) return true
+    const mine = problem.createdBy.id === user.value?.id
+    if (problem.contestId !== null) return isTeacherOrAbove.value && mine
+    return (
+      hasProblemPermission.value &&
+      (mine || user.value?.problemPermission === PROBLEM_PERMISSION.ALL)
+    )
+  }
+
   function toggleDemoMode() {
     demoSwitch.value = !demoSwitch.value
     storage.set(STORAGE_KEY.DEMO_MODE, demoSwitch.value)
@@ -124,6 +140,7 @@ export const useUserStore = defineStore("user", () => {
     hasProblemPermission,
     demoMode,
     canToggleDemoMode,
+    canEditProblem,
     toggleDemoMode,
     isAuthed,
     showSubmissions,

packages/contract/src/classroom.ts

@@ -144,6 +144,13 @@ export const classBoardStudentSchema = z.object({
    * 代码，不用等他举手。只认连着**本站**的（和课堂求助一样，在 serve 进程的内存里）
    */
   editing: z.string().nullable(),
+  /**
+   * 此刻在线（5 分钟内有动静）、今天最后一次上线的时刻（今天没上过线为 null）。
+   * 机房两人共用一台电脑时同桌只有一个登着，所以「谁没来」看 seenAt，不看 online。
+   * 和 editing 一样只认**本站**：服务器和机房各记各的（在各自的 Redis 里）
+   */
+  online: z.boolean(),
+  seenAt: z.string().nullable(),
 })
 
 /**