feat(error-book): add analytics stats, charts, and error collection

- Add analytics-stats-cards, chapter-weakness-chart, class-error-bar-chart

- Add knowledge-point-weakness-chart, subject-distribution-chart, subject-tabs

- Add class-filter and grouped-student-error-table components

- Add data-access-collection for error aggregation from multiple sources

- Update error-book-detail-dialog, data-access, and types

src/modules/error-book/components/analytics-stats-cards.tsx

@@ -0,0 +1,97 @@
+import { BookOpen, Brain, CheckCircle2, Clock, TrendingUp } from "lucide-react"
+import { Card, CardContent } from "@/shared/components/ui/card"
+import { cn } from "@/shared/lib/utils"
+
+interface AnalyticsStatsCardsProps {
+  totalStudents: number
+  studentsWithErrorBook: number
+  totalErrorItems: number
+  averageMasteryRate: number
+  dueReviewCount: number
+  /** 涉及的知识点数 */
+  knowledgePointCount?: number
+  className?: string
+}
+
+/**
+ * 错题分析统计卡片（教师/管理员视图）
+ * 5 个卡片：覆盖学生/错题总数/平均掌握率/待复习/知识点数
+ */
+export function AnalyticsStatsCards({
+  totalStudents,
+  studentsWithErrorBook,
+  totalErrorItems,
+  averageMasteryRate,
+  dueReviewCount,
+  knowledgePointCount,
+  className,
+}: AnalyticsStatsCardsProps) {
+  const cards = [
+    {
+      label: "覆盖学生",
+      value: studentsWithErrorBook,
+      sub: `/ ${totalStudents} 人`,
+      icon: BookOpen,
+      color: "text-blue-600 dark:text-blue-400",
+      bg: "bg-blue-50 dark:bg-blue-950/30",
+    },
+    {
+      label: "错题总数",
+      value: totalErrorItems,
+      sub: `人均 ${(totalStudents > 0 ? totalErrorItems / totalStudents : 0).toFixed(1)} 题`,
+      icon: TrendingUp,
+      color: "text-rose-600 dark:text-rose-400",
+      bg: "bg-rose-50 dark:bg-rose-950/30",
+    },
+    {
+      label: "平均掌握率",
+      value: `${Math.round(averageMasteryRate * 100)}%`,
+      sub: averageMasteryRate >= 0.6 ? "整体良好" : "需加强",
+      icon: CheckCircle2,
+      color: "text-emerald-600 dark:text-emerald-400",
+      bg: "bg-emerald-50 dark:bg-emerald-950/30",
+    },
+    {
+      label: "待复习",
+      value: dueReviewCount,
+      sub: dueReviewCount > 0 ? "需要关注" : "无到期",
+      icon: Clock,
+      color: "text-amber-600 dark:text-amber-400",
+      bg: "bg-amber-50 dark:bg-amber-950/30",
+    },
+    {
+      label: "涉及知识点",
+      value: knowledgePointCount ?? 0,
+      sub: knowledgePointCount && knowledgePointCount > 5 ? "范围较广" : "集中",
+      icon: Brain,
+      color: "text-purple-600 dark:text-purple-400",
+      bg: "bg-purple-50 dark:bg-purple-950/30",
+    },
+  ]
+
+  return (
+    <div className={cn("grid gap-3 sm:grid-cols-2 lg:grid-cols-5", className)}>
+      {cards.map((card) => {
+        const Icon = card.icon
+        return (
+          <Card key={card.label} className="overflow-hidden">
+            <CardContent className="p-4">
+              <div className="flex items-start justify-between">
+                <div className="min-w-0 flex-1">
+                  <div className="text-xs text-muted-foreground">{card.label}</div>
+                  <div className={cn("mt-1 text-2xl font-bold", card.color)}>
+                    {card.value}
+                  </div>
+                  <div className="mt-0.5 text-xs text-muted-foreground">{card.sub}</div>
+                </div>
+                <div className={cn("rounded-lg p-2", card.bg)}>
+                  <Icon className={cn("h-4 w-4", card.color)} />
+                </div>
+              </div>
+            </CardContent>
+          </Card>
+        )
+      })}
+    </div>
+  )
+}

src/modules/error-book/components/chapter-weakness-chart.tsx

@@ -0,0 +1,155 @@
+"use client"
+
+import { Bar, BarChart, CartesianGrid, XAxis, YAxis, Cell } from "recharts"
+import {
+  ChartContainer,
+  ChartTooltip,
+  ChartTooltipContent,
+  type ChartConfig,
+} from "@/shared/components/ui/chart"
+import { Card, CardContent, CardHeader, CardTitle } from "@/shared/components/ui/card"
+import { Badge } from "@/shared/components/ui/badge"
+import { cn } from "@/shared/lib/utils"
+
+import type { ChapterWeakness } from "@/modules/error-book/types"
+
+interface ChapterWeaknessChartProps {
+  data: ChapterWeakness[]
+  className?: string
+}
+
+/**
+ * 章节薄弱度图表（哪些课在错）
+ * 横向柱状图，按错题数降序
+ * 每个柱子可展开显示该章节下错得最多的知识点
+ */
+export function ChapterWeaknessChart({ data, className }: ChapterWeaknessChartProps) {
+  if (data.length === 0) return null
+
+  const chartData = data.map((d) => ({
+    name: d.chapterTitle,
+    errorCount: d.errorCount,
+    masteredCount: d.masteredCount,
+    masteryRate: Number((d.masteryRate * 100).toFixed(0)),
+    knowledgePointCount: d.knowledgePointCount,
+    topKps: d.topKnowledgePoints,
+  }))
+
+  const chartConfig: ChartConfig = {
+    errorCount: {
+      label: "错题数",
+      color: "var(--color-chart-2)",
+    },
+  }
+
+  return (
+    <Card className={cn("overflow-hidden", className)}>
+      <CardHeader>
+        <CardTitle className="text-base">章节错题分布（哪些课在错）</CardTitle>
+      </CardHeader>
+      <CardContent className="space-y-4">
+        <ChartContainer config={chartConfig} className="h-[300px] w-full">
+          <BarChart
+            data={chartData}
+            layout="vertical"
+            margin={{ left: 8, right: 16, top: 8, bottom: 8 }}
+          >
+            <CartesianGrid horizontal={false} strokeDasharray="4 4" strokeOpacity={0.4} />
+            <XAxis type="number" tickLine={false} axisLine={false} />
+            <YAxis
+              type="number"
+              dataKey="name"
+              tickLine={false}
+              axisLine={false}
+              width={120}
+              tickFormatter={(value: string) =>
+                value.length > 10 ? `${value.slice(0, 10)}...` : value
+              }
+            />
+            <ChartTooltip
+              content={
+                <ChartTooltipContent
+                  className="w-[280px]"
+                  formatter={(payload: unknown) => {
+                    const p = payload as unknown as {
+                      name: string
+                      errorCount: number
+                      masteredCount: number
+                      masteryRate: number
+                      knowledgePointCount: number
+                      topKps: Array<{ knowledgePointName: string; errorCount: number }>
+                    }
+                    return (
+                      <div className="space-y-1.5">
+                        <div className="font-medium">{p.name}</div>
+                        <div className="text-muted-foreground">
+                          错题数：<span className="font-medium text-foreground">{p.errorCount}</span>
+                          <span className="ml-2">已掌握：<span className="font-medium text-emerald-600">{p.masteredCount}</span></span>
+                        </div>
+                        <div className="text-muted-foreground">
+                          掌握率：<span className="font-medium text-foreground">{p.masteryRate}%</span>
+                          <span className="ml-2">知识点数：<span className="font-medium text-foreground">{p.knowledgePointCount}</span></span>
+                        </div>
+                        {p.topKps && p.topKps.length > 0 ? (
+                          <div className="border-t pt-1.5 mt-1.5">
+                            <div className="text-xs text-muted-foreground mb-1">薄弱知识点：</div>
+                            {p.topKps.map((kp) => (
+                              <div key={kp.knowledgePointName} className="flex justify-between text-xs">
+                                <span>{kp.knowledgePointName}</span>
+                                <span className="font-medium text-rose-600">{kp.errorCount}</span>
+                              </div>
+                            ))}
+                          </div>
+                        ) : null}
+                      </div>
+                    )
+                  }}
+                />
+              }
+            />
+            <Bar dataKey="errorCount" radius={[0, 4, 4, 0]}>
+              {chartData.map((entry, idx) => (
+                <Cell
+                  key={idx}
+                  fill={entry.masteryRate < 30 ? "var(--color-rose-500)" : entry.masteryRate < 60 ? "var(--color-amber-500)" : "var(--color-emerald-500)"}
+                />
+              ))}
+            </Bar>
+          </BarChart>
+        </ChartContainer>
+
+        {/* 章节详情列表 */}
+        <div className="space-y-2">
+          {data.slice(0, 5).map((chapter) => (
+            <div
+              key={chapter.chapterId}
+              className="flex items-start justify-between gap-3 rounded-lg border p-3"
+            >
+              <div className="min-w-0 flex-1 space-y-1">
+                <div className="flex items-center gap-2">
+                  <span className="truncate font-medium text-sm">{chapter.chapterTitle}</span>
+                  <Badge variant="outline" className="shrink-0 text-xs">
+                    {chapter.knowledgePointCount} 个知识点
+                  </Badge>
+                </div>
+                {chapter.topKnowledgePoints.length > 0 ? (
+                  <div className="flex flex-wrap gap-1">
+                    {chapter.topKnowledgePoints.map((kp) => (
+                      <Badge key={kp.knowledgePointId} variant="secondary" className="text-xs">
+                        {kp.knowledgePointName} · {kp.errorCount}
+                      </Badge>
+                    ))}
+                  </div>
+                ) : null}
+              </div>
+              <div className="flex shrink-0 flex-col items-end gap-0.5 text-xs">
+                <span className="font-bold text-rose-600">{chapter.errorCount}</span>
+                <span className="text-muted-foreground">掌握 {Math.round(chapter.masteryRate * 100)}%</span>
+              </div>
+            </div>
+          ))}
+        </div>
+      </CardContent>
+    </Card>
+  )
+}

src/modules/error-book/components/class-error-bar-chart.tsx

@@ -0,0 +1,118 @@
+"use client"
+
+import { Bar, BarChart, CartesianGrid, XAxis, YAxis, Cell } from "recharts"
+import {
+  ChartContainer,
+  ChartTooltip,
+  ChartTooltipContent,
+  type ChartConfig,
+} from "@/shared/components/ui/chart"
+import { Card, CardContent, CardHeader, CardTitle } from "@/shared/components/ui/card"
+import { cn } from "@/shared/lib/utils"
+
+import type { ClassErrorOverview } from "@/modules/error-book/types"
+
+interface ClassErrorBarChartProps {
+  data: ClassErrorOverview[]
+  className?: string
+}
+
+const CHART_COLORS = [
+  "var(--color-chart-1)",
+  "var(--color-chart-2)",
+  "var(--color-chart-3)",
+  "var(--color-chart-4)",
+  "var(--color-chart-5)",
+]
+
+/**
+ * 班级错题数对比柱状图（教师视图）
+ * 横轴：班级名称，纵轴：错题总数
+ * 颜色按班级区分，tooltip 显示学生数/人均/掌握率
+ */
+export function ClassErrorBarChart({ data, className }: ClassErrorBarChartProps) {
+  if (data.length === 0) return null
+
+  const chartData = data.map((d) => ({
+    name: d.className,
+    totalErrorItems: d.totalErrorItems,
+    studentCount: d.studentCount,
+    averageErrorPerStudent: Number(d.averageErrorPerStudent.toFixed(1)),
+    averageMasteryRate: Number((d.averageMasteryRate * 100).toFixed(0)),
+    dueReviewCount: d.dueReviewCount,
+  }))
+
+  const chartConfig: ChartConfig = {
+    totalErrorItems: {
+      label: "错题总数",
+      color: "var(--color-chart-1)",
+    },
+  }
+
+  return (
+    <Card className={cn("overflow-hidden", className)}>
+      <CardHeader>
+        <CardTitle className="text-base">各班级错题数对比</CardTitle>
+      </CardHeader>
+      <CardContent>
+        <ChartContainer config={chartConfig} className="h-[280px] w-full">
+          <BarChart data={chartData} margin={{ left: 8, right: 8, top: 8, bottom: 8 }}>
+            <CartesianGrid vertical={false} strokeDasharray="4 4" strokeOpacity={0.4} />
+            <XAxis
+              dataKey="name"
+              tickLine={false}
+              axisLine={false}
+              tickMargin={8}
+              tickFormatter={(value: string) =>
+                value.length > 8 ? `${value.slice(0, 8)}...` : value
+              }
+            />
+            <YAxis tickLine={false} axisLine={false} width={36} />
+            <ChartTooltip
+              content={
+                <ChartTooltipContent
+                  className="w-[220px]"
+                  formatter={(payload: unknown) => {
+                    const p = payload as unknown as {
+                      name: string
+                      totalErrorItems: number
+                      studentCount: number
+                      averageErrorPerStudent: number
+                      averageMasteryRate: number
+                      dueReviewCount: number
+                    }
+                    return (
+                      <div className="space-y-1.5">
+                        <div className="font-medium">{p.name}</div>
+                        <div className="text-muted-foreground">
+                          错题总数：<span className="font-medium text-foreground">{p.totalErrorItems}</span>
+                        </div>
+                        <div className="text-muted-foreground">
+                          学生数：<span className="font-medium text-foreground">{p.studentCount}</span>
+                        </div>
+                        <div className="text-muted-foreground">
+                          人均错题：<span className="font-medium text-foreground">{p.averageErrorPerStudent}</span>
+                        </div>
+                        <div className="text-muted-foreground">
+                          平均掌握率：<span className="font-medium text-foreground">{p.averageMasteryRate}%</span>
+                        </div>
+                        <div className="text-muted-foreground">
+                          待复习：<span className="font-medium text-rose-600">{p.dueReviewCount}</span>
+                        </div>
+                      </div>
+                    )
+                  }}
+                />
+              }
+            />
+            <Bar dataKey="totalErrorItems" radius={[4, 4, 0, 0]}>
+              {chartData.map((_, idx) => (
+                <Cell key={idx} fill={CHART_COLORS[idx % CHART_COLORS.length]} />
+              ))}
+            </Bar>
+          </BarChart>
+        </ChartContainer>
+      </CardContent>
+    </Card>
+  )
+}

src/modules/error-book/components/class-filter.tsx

@@ -0,0 +1,91 @@
+"use client"
+
+import { useRouter, useSearchParams } from "next/navigation"
+import { cn } from "@/shared/lib/utils"
+import { Badge } from "@/shared/components/ui/badge"
+
+import type { ClassErrorOverview } from "@/modules/error-book/types"
+
+interface ClassFilterProps {
+  classes: ClassErrorOverview[]
+  /** 当前选中的班级 ID（"all" 表示全部） */
+  currentClassId: string
+  /** URL 参数名（默认 "classId"） */
+  paramName?: string
+}
+
+/**
+ * 班级筛选器（教师视图）
+ * 显示教师所教的所有班级，点击切换查看单个班级
+ */
+export function ClassFilter({
+  classes,
+  currentClassId,
+  paramName = "classId",
+}: ClassFilterProps) {
+  const router = useRouter()
+  const searchParams = useSearchParams()
+
+  const handleSelect = (classId: string) => {
+    const params = new URLSearchParams(searchParams.toString())
+    if (classId === "all") {
+      params.delete(paramName)
+    } else {
+      params.set(paramName, classId)
+    }
+    router.push(`?${params.toString()}`, { scroll: false })
+  }
+
+  if (classes.length === 0) return null
+
+  return (
+    <div className="flex flex-wrap gap-2">
+      <button
+        type="button"
+        onClick={() => handleSelect("all")}
+        className={cn(
+          "inline-flex items-center gap-2 rounded-md border px-3 py-1.5 text-sm transition-colors",
+          currentClassId === "all"
+            ? "border-primary bg-primary text-primary-foreground"
+            : "bg-card hover:bg-muted"
+        )}
+      >
+        <span className="font-medium">全部班级</span>
+      </button>
+      {classes.map((cls) => {
+        const isActive = currentClassId === cls.classId
+        return (
+          <button
+            key={cls.classId}
+            type="button"
+            onClick={() => handleSelect(cls.classId)}
+            className={cn(
+              "inline-flex items-center gap-2 rounded-md border px-3 py-1.5 text-sm transition-colors",
+              isActive
+                ? "border-primary bg-primary text-primary-foreground"
+                : "bg-card hover:bg-muted"
+            )}
+          >
+            <span className="font-medium">{cls.className}</span>
+            <Badge
+              variant={isActive ? "secondary" : "outline"}
+              className="text-xs"
+            >
+              {cls.totalErrorItems} 错题
+            </Badge>
+            {cls.dueReviewCount > 0 ? (
+              <span
+                className={cn(
+                  "text-xs",
+                  isActive ? "text-primary-foreground/80" : "text-rose-600"
+                )}
+              >
+                {cls.dueReviewCount} 待复习
+              </span>
+            ) : null}
+          </button>
+        )
+      })}
+    </div>
+  )
+}

src/modules/error-book/components/error-book-detail-dialog.tsx

@@ -1,7 +1,9 @@
 "use client"
 
 import { useState, useTransition } from "react"
-import { Archive, Trash2, FileText, Calendar, History } from "lucide-react"
+import { useRouter } from "next/navigation"
+import { useTranslations } from "next-intl"
+import { Archive, Trash2, FileText, Calendar, History, Target } from "lucide-react"
 import { toast } from "sonner"
 
 import {
@@ -36,6 +38,7 @@ import {
 } from "../types"
 import { ReviewButtons } from "./review-buttons"
 import { AiErrorBookAnalysis } from "@/modules/ai/components/ai-error-book-analysis"
+import { createPracticeSessionAction } from "@/modules/adaptive-practice/actions"
 
 interface ErrorBookDetailDialogProps {
   item: ErrorBookItemDetail | (Omit<ErrorBookItemDetail, "reviews"> & { reviews?: ErrorBookItemDetail["reviews"] })
@@ -89,6 +92,9 @@ export function ErrorBookDetailDialog({ item, trigger, studentId, errorItems }:
   const [isPending, startTransition] = useTransition()
   const [note, setNote] = useState(item.note ?? "")
   const [errorTags, setErrorTags] = useState<string[]>(item.errorTags ?? [])
+  const router = useRouter()
+  const t = useTranslations("error-book")
+  const tPractice = useTranslations("practice")
 
   function handleSaveNote() {
     startTransition(async () => {
@@ -99,9 +105,9 @@ export function ErrorBookDetailDialog({ item, trigger, studentId, errorItems }:
       )
       const res = await updateErrorBookNoteAction(undefined, formData)
       if (res.success) {
-        toast.success("笔记已保存")
+        toast.success(t("messages.noteSaved"))
       } else {
-        toast.error(res.message ?? "保存失败")
+        toast.error(res.message ?? t("messages.saveFailed"))
       }
     })
   }
@@ -112,10 +118,10 @@ export function ErrorBookDetailDialog({ item, trigger, studentId, errorItems }:
       formData.append("itemId", item.id)
       const res = await archiveErrorBookItemAction(undefined, formData)
       if (res.success) {
-        toast.success(res.message ?? "已归档")
+        toast.success(t("messages.archived"))
         setOpen(false)
       } else {
-        toast.error(res.message ?? "归档失败")
+        toast.error(res.message ?? t("messages.archiveFailed"))
       }
     })
   }
@@ -126,10 +132,42 @@ export function ErrorBookDetailDialog({ item, trigger, studentId, errorItems }:
       formData.append("itemId", item.id)
       const res = await deleteErrorBookItemAction(undefined, formData)
       if (res.success) {
-        toast.success(res.message ?? "已删除")
+        toast.success(t("messages.deleted"))
         setOpen(false)
       } else {
-        toast.error(res.message ?? "删除失败")
+        toast.error(res.message ?? t("messages.deleteFailed"))
+      }
+    })
+  }
+
+  /**
+   * 发起错题变式练习。
+   *
+   * 从当前错题出发，创建一个 error_variant 类型的练习会话，
+   * 使用该错题关联的原题进行针对性练习。
+   */
+  function handleStartVariantPractice() {
+    startTransition(async () => {
+      const formData = new FormData()
+      formData.append(
+        "json",
+        JSON.stringify({
+          practiceType: "error_variant",
+          subjectId: item.subjectId ?? undefined,
+          sourceMeta: {
+            errorBookItemIds: [item.id],
+            sourceQuestionIds: [item.questionId],
+          },
+          questionCount: 10,
+        }),
+      )
+      const res = await createPracticeSessionAction(undefined, formData)
+      if (res.success && res.data) {
+        toast.success(res.message ?? tPractice("starter.title"))
+        setOpen(false)
+        router.push(`/student/practice/${res.data.sessionId}`)
+      } else {
+        toast.error(res.message ?? t("messages.saveFailed"))
       }
     })
   }
@@ -243,6 +281,22 @@ export function ErrorBookDetailDialog({ item, trigger, studentId, errorItems }:
               </section>
             ) : null}
 
+            {/* 变式练习入口 */}
+            <section>
+              <Button
+                onClick={handleStartVariantPractice}
+                disabled={isPending}
+                className="w-full"
+                variant="default"
+              >
+                <Target className="h-4 w-4" />
+                {isPending ? tPractice("starter.creating") : tPractice("types.error_variant")}
+              </Button>
+              <p className="mt-1 text-xs text-muted-foreground text-center">
+                {tPractice("starter.description")}
+              </p>
+            </section>
+
             {/* 复习区 */}
             {item.status !== "mastered" && item.status !== "archived" ? (
               <section>

src/modules/error-book/components/grouped-student-error-table.tsx

@@ -0,0 +1,209 @@
+"use client"
+
+import { useState } from "react"
+import { ChevronDown, ChevronRight, Users } from "lucide-react"
+
+import { Badge } from "@/shared/components/ui/badge"
+import { Progress } from "@/shared/components/ui/progress"
+import { cn } from "@/shared/lib/utils"
+
+import type { StudentErrorBookSummary } from "@/modules/error-book/types"
+
+interface GroupedStudentErrorTableProps {
+  students: StudentErrorBookSummary[]
+  studentNames: Map<string, string>
+  basePath: string
+}
+
+interface ClassGroup {
+  classId: string | null
+  className: string
+  students: StudentErrorBookSummary[]
+  totalErrors: number
+  averageMasteryRate: number
+}
+
+/**
+ * 按班级分组的学生错题表格（教师视图）
+ * 每个班级可展开/折叠，显示该班学生的错题详情
+ */
+export function GroupedStudentErrorTable({
+  students,
+  studentNames,
+  basePath,
+}: GroupedStudentErrorTableProps) {
+  const [expandedClasses, setExpandedClasses] = useState<Set<string>>(new Set())
+
+  // 按班级分组
+  const groups: ClassGroup[] = []
+  const groupMap = new Map<string | null, ClassGroup>()
+
+  for (const student of students) {
+    const key = student.classId
+    let group = groupMap.get(key)
+    if (!group) {
+      group = {
+        classId: key,
+        className: student.className ?? "未分班",
+        students: [],
+        totalErrors: 0,
+        averageMasteryRate: 0,
+      }
+      groupMap.set(key, group)
+      groups.push(group)
+    }
+    group.students.push(student)
+    group.totalErrors += student.totalCount
+  }
+
+  // 计算每组的平均掌握率并排序
+  for (const group of groups) {
+    const studentsWithErrors = group.students.filter((s) => s.totalCount > 0)
+    group.averageMasteryRate =
+      studentsWithErrors.length > 0
+        ? studentsWithErrors.reduce((sum, s) => sum + s.masteredRate, 0) / studentsWithErrors.length
+        : 0
+    // 按错题数降序
+    group.students.sort((a, b) => b.totalCount - a.totalCount)
+  }
+  groups.sort((a, b) => b.totalErrors - a.totalErrors)
+
+  const toggleClass = (classId: string | null) => {
+    const key = classId ?? "unclassified"
+    setExpandedClasses((prev) => {
+      const next = new Set(prev)
+      if (next.has(key)) {
+        next.delete(key)
+      } else {
+        next.add(key)
+      }
+      return next
+    })
+  }
+
+  if (groups.length === 0) return null
+
+  return (
+    <div className="space-y-3">
+      {groups.map((group) => {
+        const groupKey = group.classId ?? "unclassified"
+        const isExpanded = expandedClasses.has(groupKey)
+        const studentsWithErrors = group.students.filter((s) => s.totalCount > 0)
+
+        return (
+          <div key={groupKey} className="overflow-hidden rounded-lg border">
+            {/* 班级头部（可点击展开） */}
+            <button
+              type="button"
+              onClick={() => toggleClass(group.classId)}
+              className="flex w-full items-center justify-between gap-3 bg-muted/50 p-3 text-left transition-colors hover:bg-muted"
+            >
+              <div className="flex items-center gap-2">
+                {isExpanded ? (
+                  <ChevronDown className="h-4 w-4 text-muted-foreground" />
+                ) : (
+                  <ChevronRight className="h-4 w-4 text-muted-foreground" />
+                )}
+                <Users className="h-4 w-4 text-muted-foreground" />
+                <span className="font-medium">{group.className}</span>
+                <Badge variant="outline" className="text-xs">
+                  {group.students.length} 人
+                </Badge>
+                {studentsWithErrors.length < group.students.length ? (
+                  <Badge variant="secondary" className="text-xs">
+                    {studentsWithErrors.length} 人有错题
+                  </Badge>
+                ) : null}
+              </div>
+              <div className="flex items-center gap-4 text-sm">
+                <div className="text-right">
+                  <div className="text-xs text-muted-foreground">错题总数</div>
+                  <div className="font-bold text-rose-600">{group.totalErrors}</div>
+                </div>
+                <div className="text-right">
+                  <div className="text-xs text-muted-foreground">平均掌握率</div>
+                  <div className="font-medium">
+                    {Math.round(group.averageMasteryRate * 100)}%
+                  </div>
+                </div>
+              </div>
+            </button>
+
+            {/* 学生表格（展开时显示） */}
+            {isExpanded ? (
+              <div className="overflow-x-auto">
+                <table className="w-full text-sm">
+                  <thead className="border-b bg-muted/30">
+                    <tr className="text-left text-xs text-muted-foreground">
+                      <th className="px-3 py-2 font-medium">学生</th>
+                      <th className="px-3 py-2 text-right font-medium">错题总数</th>
+                      <th className="px-3 py-2 text-right font-medium">待学习</th>
+                      <th className="px-3 py-2 text-right font-medium">学习中</th>
+                      <th className="px-3 py-2 text-right font-medium">已掌握</th>
+                      <th className="px-3 py-2 text-right font-medium">待复习</th>
+                      <th className="px-3 py-2 font-medium">掌握率</th>
+                    </tr>
+                  </thead>
+                  <tbody>
+                    {group.students.map((student) => {
+                      const name = studentNames.get(student.studentId) ?? "未知"
+                      const hasErrors = student.totalCount > 0
+                      return (
+                        <tr
+                          key={student.studentId}
+                          className={cn(
+                            "border-b last:border-0 transition-colors",
+                            hasErrors ? "hover:bg-muted/50" : "opacity-50"
+                          )}
+                        >
+                          <td className="px-3 py-2">
+                            {hasErrors ? (
+                              <a
+                                href={`${basePath}?studentId=${student.studentId}`}
+                                className="font-medium text-primary hover:underline"
+                              >
+                                {name}
+                              </a>
+                            ) : (
+                              <span className="text-muted-foreground">{name}</span>
+                            )}
+                          </td>
+                          <td className="px-3 py-2 text-right font-medium">
+                            {student.totalCount}
+                          </td>
+                          <td className="px-3 py-2 text-right text-blue-600 dark:text-blue-400">
+                            {student.newCount}
+                          </td>
+                          <td className="px-3 py-2 text-right">
+                            {student.learningCount}
+                          </td>
+                          <td className="px-3 py-2 text-right text-emerald-600 dark:text-emerald-400">
+                            {student.masteredCount}
+                          </td>
+                          <td className="px-3 py-2 text-right text-rose-600 dark:text-rose-400">
+                            {student.dueReviewCount}
+                          </td>
+                          <td className="px-3 py-2">
+                            <div className="flex items-center gap-2">
+                              <Progress
+                                value={student.masteredRate * 100}
+                                className="h-1.5 w-16"
+                              />
+                              <span className="text-xs text-muted-foreground">
+                                {Math.round(student.masteredRate * 100)}%
+                              </span>
+                            </div>
+                          </td>
+                        </tr>
+                      )
+                    })}
+                  </tbody>
+                </table>
+              </div>
+            ) : null}
+          </div>
+        )
+      })}
+    </div>
+  )
+}

src/modules/error-book/components/knowledge-point-weakness-chart.tsx

@@ -0,0 +1,156 @@
+"use client"
+
+import { Bar, BarChart, CartesianGrid, XAxis, YAxis, Cell } from "recharts"
+import {
+  ChartContainer,
+  ChartTooltip,
+  ChartTooltipContent,
+  type ChartConfig,
+} from "@/shared/components/ui/chart"
+import { Card, CardContent, CardHeader, CardTitle } from "@/shared/components/ui/card"
+import { Badge } from "@/shared/components/ui/badge"
+import { cn } from "@/shared/lib/utils"
+
+import type { KnowledgePointWeakness } from "@/modules/error-book/types"
+
+interface KnowledgePointWeaknessChartProps {
+  data: KnowledgePointWeakness[]
+  className?: string
+}
+
+/**
+ * 知识点薄弱度图表
+ * 横向柱状图，按错题数降序
+ * 颜色按掌握率区分（红/黄/绿）
+ * 显示所属章节
+ */
+export function KnowledgePointWeaknessChart({
+  data,
+  className,
+}: KnowledgePointWeaknessChartProps) {
+  if (data.length === 0) return null
+
+  const chartData = data.map((d) => ({
+    name: d.knowledgePointName,
+    errorCount: d.errorCount,
+    masteredCount: d.masteredCount,
+    masteryRate: Number((d.masteryRate * 100).toFixed(0)),
+    chapterTitle: d.chapterTitle ?? "未分类",
+  }))
+
+  const chartConfig: ChartConfig = {
+    errorCount: {
+      label: "错题数",
+      color: "var(--color-chart-1)",
+    },
+  }
+
+  return (
+    <Card className={cn("overflow-hidden", className)}>
+      <CardHeader>
+        <CardTitle className="text-base">薄弱知识点 Top {data.length}</CardTitle>
+      </CardHeader>
+      <CardContent className="space-y-4">
+        <ChartContainer config={chartConfig} className="h-[320px] w-full">
+          <BarChart
+            data={chartData}
+            layout="vertical"
+            margin={{ left: 8, right: 16, top: 8, bottom: 8 }}
+          >
+            <CartesianGrid horizontal={false} strokeDasharray="4 4" strokeOpacity={0.4} />
+            <XAxis type="number" tickLine={false} axisLine={false} />
+            <YAxis
+              type="number"
+              dataKey="name"
+              tickLine={false}
+              axisLine={false}
+              width={100}
+              tickFormatter={(value: string) =>
+                value.length > 8 ? `${value.slice(0, 8)}...` : value
+              }
+            />
+            <ChartTooltip
+              content={
+                <ChartTooltipContent
+                  className="w-[240px]"
+                  formatter={(payload: unknown) => {
+                    const p = payload as unknown as {
+                      name: string
+                      errorCount: number
+                      masteredCount: number
+                      masteryRate: number
+                      chapterTitle: string
+                    }
+                    return (
+                      <div className="space-y-1.5">
+                        <div className="font-medium">{p.name}</div>
+                        <div className="text-xs text-muted-foreground">
+                          所属章节：{p.chapterTitle}
+                        </div>
+                        <div className="text-muted-foreground">
+                          错题数：<span className="font-medium text-foreground">{p.errorCount}</span>
+                          <span className="ml-2">已掌握：<span className="font-medium text-emerald-600">{p.masteredCount}</span></span>
+                        </div>
+                        <div className="text-muted-foreground">
+                          掌握率：<span className="font-medium text-foreground">{p.masteryRate}%</span>
+                        </div>
+                      </div>
+                    )
+                  }}
+                />
+              }
+            />
+            <Bar dataKey="errorCount" radius={[0, 4, 4, 0]}>
+              {chartData.map((entry, idx) => (
+                <Cell
+                  key={idx}
+                  fill={
+                    entry.masteryRate < 30
+                      ? "var(--color-rose-500)"
+                      : entry.masteryRate < 60
+                        ? "var(--color-amber-500)"
+                        : "var(--color-emerald-500)"
+                  }
+                />
+              ))}
+            </Bar>
+          </BarChart>
+        </ChartContainer>
+
+        {/* 知识点详情列表（带章节归属） */}
+        <div className="space-y-2">
+          {data.slice(0, 8).map((kp) => (
+            <div
+              key={kp.knowledgePointId}
+              className="flex items-center justify-between gap-3 rounded-lg border p-2.5"
+            >
+              <div className="min-w-0 flex-1">
+                <div className="truncate text-sm font-medium">{kp.knowledgePointName}</div>
+                {kp.chapterTitle ? (
+                  <div className="truncate text-xs text-muted-foreground">
+                    {kp.chapterTitle}
+                  </div>
+                ) : null}
+              </div>
+              <div className="flex shrink-0 items-center gap-2">
+                <Badge
+                  variant={
+                    kp.masteryRate < 0.3
+                      ? "destructive"
+                      : kp.masteryRate < 0.6
+                        ? "secondary"
+                        : "outline"
+                  }
+                  className="text-xs"
+                >
+                  {Math.round(kp.masteryRate * 100)}%
+                </Badge>
+                <span className="text-sm font-bold text-rose-600">{kp.errorCount}</span>
+              </div>
+            </div>
+          ))}
+        </div>
+      </CardContent>
+    </Card>
+  )
+}

src/modules/error-book/components/subject-distribution-chart.tsx

@@ -0,0 +1,111 @@
+"use client"
+
+import { Bar, BarChart, CartesianGrid, XAxis, YAxis, Cell } from "recharts"
+import {
+  ChartContainer,
+  ChartTooltip,
+  ChartTooltipContent,
+  type ChartConfig,
+} from "@/shared/components/ui/chart"
+import { Card, CardContent, CardHeader, CardTitle } from "@/shared/components/ui/card"
+import { cn } from "@/shared/lib/utils"
+
+import type { SubjectErrorDistribution } from "@/modules/error-book/types"
+
+interface SubjectDistributionChartProps {
+  data: SubjectErrorDistribution[]
+  className?: string
+}
+
+const SUBJECT_COLORS = [
+  "var(--color-chart-1)",
+  "var(--color-chart-2)",
+  "var(--color-chart-3)",
+  "var(--color-chart-4)",
+  "var(--color-chart-5)",
+]
+
+/**
+ * 学科错题分布柱状图（管理员视图）
+ * 横轴：学科名称，纵轴：错题数
+ * tooltip 显示已掌握/掌握率
+ */
+export function SubjectDistributionChart({
+  data,
+  className,
+}: SubjectDistributionChartProps) {
+  if (data.length === 0) return null
+
+  const chartData = data.map((d) => ({
+    name: d.subjectName,
+    errorCount: d.errorCount,
+    masteredCount: d.masteredCount,
+    masteryRate: Number((d.masteryRate * 100).toFixed(0)),
+  }))
+
+  const chartConfig: ChartConfig = {
+    errorCount: {
+      label: "错题数",
+      color: "var(--color-chart-1)",
+    },
+  }
+
+  return (
+    <Card className={cn("overflow-hidden", className)}>
+      <CardHeader>
+        <CardTitle className="text-base">各学科错题分布</CardTitle>
+      </CardHeader>
+      <CardContent>
+        <ChartContainer config={chartConfig} className="h-[280px] w-full">
+          <BarChart data={chartData} margin={{ left: 8, right: 8, top: 8, bottom: 8 }}>
+            <CartesianGrid vertical={false} strokeDasharray="4 4" strokeOpacity={0.4} />
+            <XAxis
+              dataKey="name"
+              tickLine={false}
+              axisLine={false}
+              tickMargin={8}
+              tickFormatter={(value: string) =>
+                value.length > 6 ? `${value.slice(0, 6)}...` : value
+              }
+            />
+            <YAxis tickLine={false} axisLine={false} width={36} />
+            <ChartTooltip
+              content={
+                <ChartTooltipContent
+                  className="w-[200px]"
+                  formatter={(payload: unknown) => {
+                    const p = payload as unknown as {
+                      name: string
+                      errorCount: number
+                      masteredCount: number
+                      masteryRate: number
+                    }
+                    return (
+                      <div className="space-y-1.5">
+                        <div className="font-medium">{p.name}</div>
+                        <div className="text-muted-foreground">
+                          错题数：<span className="font-medium text-foreground">{p.errorCount}</span>
+                        </div>
+                        <div className="text-muted-foreground">
+                          已掌握：<span className="font-medium text-emerald-600">{p.masteredCount}</span>
+                        </div>
+                        <div className="text-muted-foreground">
+                          掌握率：<span className="font-medium text-foreground">{p.masteryRate}%</span>
+                        </div>
+                      </div>
+                    )
+                  }}
+                />
+              }
+            />
+            <Bar dataKey="errorCount" radius={[4, 4, 0, 0]}>
+              {chartData.map((_, idx) => (
+                <Cell key={idx} fill={SUBJECT_COLORS[idx % SUBJECT_COLORS.length]} />
+              ))}
+            </Bar>
+          </BarChart>
+        </ChartContainer>
+      </CardContent>
+    </Card>
+  )
+}

src/modules/error-book/components/subject-tabs.tsx

@@ -0,0 +1,99 @@
+"use client"
+
+import { useRouter, useSearchParams } from "next/navigation"
+import { cn } from "@/shared/lib/utils"
+import { Badge } from "@/shared/components/ui/badge"
+
+import type { SubjectErrorOverview } from "@/modules/error-book/types"
+
+interface SubjectTabsProps {
+  subjects: SubjectErrorOverview[]
+  /** 当前选中的学科 ID（null 表示全部） */
+  currentSubjectId: string | null
+  /** URL 参数名（默认 "subject"） */
+  paramName?: string
+}
+
+/**
+ * 学科切换 Tab（教师/管理员视图）
+ * 显示每个学科的错题数概览，点击切换
+ */
+export function SubjectTabs({
+  subjects,
+  currentSubjectId,
+  paramName = "subject",
+}: SubjectTabsProps) {
+  const router = useRouter()
+  const searchParams = useSearchParams()
+
+  const handleSelect = (subjectId: string | null) => {
+    const params = new URLSearchParams(searchParams.toString())
+    if (subjectId === null) {
+      params.delete(paramName)
+    } else {
+      params.set(paramName, subjectId)
+    }
+    router.push(`?${params.toString()}`, { scroll: false })
+  }
+
+  if (subjects.length === 0) return null
+
+  const totalErrors = subjects.reduce((sum, s) => sum + s.totalErrorItems, 0)
+
+  return (
+    <div className="flex flex-wrap gap-2">
+      <button
+        type="button"
+        onClick={() => handleSelect(null)}
+        className={cn(
+          "inline-flex items-center gap-2 rounded-full border px-3 py-1.5 text-sm transition-colors",
+          currentSubjectId === null
+            ? "border-primary bg-primary text-primary-foreground"
+            : "bg-card hover:bg-muted"
+        )}
+      >
+        <span className="font-medium">全部学科</span>
+        <Badge
+          variant={currentSubjectId === null ? "secondary" : "outline"}
+          className="text-xs"
+        >
+          {totalErrors}
+        </Badge>
+      </button>
+      {subjects.map((subject) => {
+        const isActive = currentSubjectId === subject.subjectId
+        return (
+          <button
+            key={subject.subjectId}
+            type="button"
+            onClick={() => handleSelect(subject.subjectId)}
+            className={cn(
+              "inline-flex items-center gap-2 rounded-full border px-3 py-1.5 text-sm transition-colors",
+              isActive
+                ? "border-primary bg-primary text-primary-foreground"
+                : "bg-card hover:bg-muted"
+            )}
+          >
+            <span className="font-medium">{subject.subjectName}</span>
+            <Badge
+              variant={isActive ? "secondary" : "outline"}
+              className="text-xs"
+            >
+              {subject.totalErrorItems}
+            </Badge>
+            {subject.dueReviewCount > 0 ? (
+              <span
+                className={cn(
+                  "text-xs",
+                  isActive ? "text-primary-foreground/80" : "text-rose-600"
+                )}
+              >
+                待复习 {subject.dueReviewCount}
+              </span>
+            ) : null}
+          </button>
+        )
+      })}
+    </div>
+  )
+}

src/modules/error-book/data-access-collection.ts

@@ -0,0 +1,170 @@
+import "server-only"
+
+import { and, eq, inArray } from "drizzle-orm"
+import { createId } from "@paralleldrive/cuid2"
+
+import { db } from "@/shared/db"
+import { errorBookItems } from "@/shared/db/schema"
+import { getExamSubmissionDataForErrorCollection } from "@/modules/exams/data-access-error-collection"
+import { getHomeworkSubmissionDataForErrorCollection } from "@/modules/homework/data-access-error-collection"
+import {
+  getKnowledgePointsForQuestions,
+  getQuestionsContentForErrorCollection,
+} from "@/modules/questions/data-access"
+import { extractCorrectAnswer } from "@/shared/lib/question-content"
+
+/**
+ * 错题采集的答案数据（由各模块的跨模块接口返回）
+ */
+type AnswerForCollection = {
+  questionId: string
+  answerContent: unknown
+  score: number | null
+  feedback: string | null
+  maxScore: number
+}
+
+/**
+ * 从答案列表中采集错题并写入 errorBookItems 表。
+ *
+ * 这是 collectFromExamSubmission 和 collectFromHomeworkSubmission 的共享逻辑：
+ * 1. 筛选错题（score < maxScore）
+ * 2. 查询已存在的错题避免重复
+ * 3. 获取题目关联的知识点（通过 questions 模块跨模块接口）
+ * 4. 获取题目内容并提取正确答案（通过 questions 模块 + shared 纯函数）
+ * 5. 批量插入错题
+ *
+ * @param studentId 学生 ID
+ * @param sourceType 错题来源类型 ("exam" | "homework")
+ * @param sourceId 来源提交 ID
+ * @param subjectId 学科 ID（可为 null）
+ * @param answers 答案列表
+ * @returns 新采集的错题数量
+ */
+async function collectErrorItemsFromAnswers(
+  studentId: string,
+  sourceType: "exam" | "homework",
+  sourceId: string,
+  subjectId: string | null,
+  answers: AnswerForCollection[],
+): Promise<number> {
+  // 筛选错题：得分为 0 或低于满分
+  const wrongAnswers = answers.filter((a) => (a.score ?? 0) < a.maxScore)
+
+  if (wrongAnswers.length === 0) return 0
+
+  const wrongQuestionIds = wrongAnswers.map((a) => a.questionId)
+
+  // 并行查询：已存在的错题、知识点关联、题目内容
+  const [existing, kpMap, questionContentMap] = await Promise.all([
+    db
+      .select({ questionId: errorBookItems.questionId })
+      .from(errorBookItems)
+      .where(
+        and(
+          eq(errorBookItems.studentId, studentId),
+          inArray(errorBookItems.questionId, wrongQuestionIds),
+        ),
+      ),
+    getKnowledgePointsForQuestions(wrongQuestionIds),
+    getQuestionsContentForErrorCollection(wrongQuestionIds),
+  ])
+
+  const existingSet = new Set(existing.map((e) => e.questionId))
+
+  const now = new Date()
+  const toInsert = wrongAnswers
+    .filter((a) => !existingSet.has(a.questionId))
+    .map((a) => {
+      // 从题目内容中提取正确答案
+      const questionData = questionContentMap.get(a.questionId)
+      const correctAnswer = questionData
+        ? extractCorrectAnswer(questionData.type, questionData.content)
+        : null
+
+      // 提取知识点 ID 列表
+      const kpLinks = kpMap.get(a.questionId) ?? []
+      const knowledgePointIds = kpLinks.length > 0 ? kpLinks.map((k) => k.knowledgePointId) : null
+
+      return {
+        id: createId(),
+        studentId,
+        questionId: a.questionId,
+        sourceType,
+        sourceId,
+        studentAnswer: a.answerContent,
+        correctAnswer,
+        subjectId,
+        knowledgePointIds,
+        status: "new" as const,
+        masteryLevel: 0,
+        nextReviewAt: now,
+        reviewInterval: 1,
+        reviewCount: 0,
+        correctStreak: 0,
+        note: a.feedback ?? null,
+        errorTags: null,
+      }
+    })
+
+  if (toInsert.length > 0) {
+    await db.insert(errorBookItems).values(toInsert)
+  }
+
+  return toInsert.length
+}
+
+/**
+ * 自动采集：从考试提交中收集错题。
+ *
+ * 通过 exams 模块的跨模块接口获取提交数据，避免直接查询
+ * examSubmissions、submissionAnswers、examQuestions、exams 等表。
+ *
+ * @param submissionId 考试提交 ID
+ * @param studentId 学生 ID（用于校验提交归属）
+ * @returns 新采集的错题数量
+ * @throws 若提交记录不存在或 studentId 不匹配
+ */
+export async function collectFromExamSubmission(
+  submissionId: string,
+  studentId: string,
+): Promise<number> {
+  const data = await getExamSubmissionDataForErrorCollection(submissionId, studentId)
+  if (!data) throw new Error("考试提交记录不存在")
+
+  return collectErrorItemsFromAnswers(
+    studentId,
+    "exam",
+    submissionId,
+    data.subjectId,
+    data.answers,
+  )
+}
+
+/**
+ * 自动采集：从作业提交中收集错题。
+ *
+ * 通过 homework 模块的跨模块接口获取提交数据，避免直接查询
+ * homeworkSubmissions、homeworkAssignments、homeworkAnswers、
+ * homeworkAssignmentQuestions、exams 等表。
+ *
+ * @param submissionId 作业提交 ID
+ * @param studentId 学生 ID
+ * @returns 新采集的错题数量
+ * @throws 若提交记录不存在
+ */
+export async function collectFromHomeworkSubmission(
+  submissionId: string,
+  studentId: string,
+): Promise<number> {
+  const data = await getHomeworkSubmissionDataForErrorCollection(submissionId)
+  if (!data) throw new Error("作业提交记录不存在")
+
+  return collectErrorItemsFromAnswers(
+    studentId,
+    "homework",
+    submissionId,
+    data.subjectId,
+    data.answers,
+  )
+}

src/modules/error-book/data-access.ts

@@ -8,17 +8,14 @@ import { db } from "@/shared/db"
 import {
   errorBookItems,
   errorBookReviews,
-  examSubmissions,
-  submissionAnswers,
-  homeworkSubmissions,
-  homeworkAnswers,
   questions,
   questionsToKnowledgePoints,
   knowledgePoints,
+  chapters,
   subjects,
-  examQuestions,
-  homeworkAssignmentQuestions,
   users,
+  classEnrollments,
+  classes,
 } from "@/shared/db/schema"
 import { getStudentIdsByClassIds } from "@/modules/classes/data-access"
 import {
@@ -37,6 +34,11 @@ import type {
   ErrorBookStats,
   ErrorBookStatusValue,
   GetErrorBookItemsParams,
+  KnowledgePointWeakness,
+  ChapterWeakness,
+  ClassErrorOverview,
+  SubjectErrorOverview,
+  StudentErrorBookSummary,
 } from "./types"
 import type { ErrorBookReviewResult } from "./schema"
 
@@ -436,259 +438,41 @@ export async function archiveErrorBookItem(itemId: string, studentId: string): P
 }
 
 // ---------------------------------------------------------------------------
-// 自动采集：从考试提交中收集错题
+// 自动采集函数已迁移至 data-access-collection.ts
+// 通过跨模块接口（exams/homework/questions data-access）避免直查多表，修复三层架构违规
 // ---------------------------------------------------------------------------
 
-export async function collectFromExamSubmission(
-  submissionId: string,
-  studentId: string
-): Promise<number> {
-  const submission = await db.query.examSubmissions.findFirst({
-    where: and(
-      eq(examSubmissions.id, submissionId),
-      eq(examSubmissions.studentId, studentId)
-    ),
-  })
-
-  if (!submission) throw new Error("考试提交记录不存在")
-
-  // 查询该提交的所有作答
-  const answers = await db
-    .select({
-      answerId: submissionAnswers.id,
-      questionId: submissionAnswers.questionId,
-      answerContent: submissionAnswers.answerContent,
-      score: submissionAnswers.score,
-      feedback: submissionAnswers.feedback,
-    })
-    .from(submissionAnswers)
-    .where(eq(submissionAnswers.submissionId, submissionId))
-
-  // 查询题目满分（用于判断是否答错）
-  const questionIds = answers.map((a) => a.questionId)
-  const examQuestionScores = await db
-    .select({
-      questionId: examQuestions.questionId,
-      maxScore: examQuestions.score,
-    })
-    .from(examQuestions)
-    .where(
-      and(
-        eq(examQuestions.examId, submission.examId),
-        inArray(examQuestions.questionId, questionIds)
-      )
-    )
-
-  const maxScoreMap = new Map(examQuestionScores.map((q) => [q.questionId, q.maxScore ?? 0]))
-
-  // 筛选错题：得分为 0 或低于满分
-  const wrongAnswers = answers.filter((a) => {
-    const max = maxScoreMap.get(a.questionId) ?? 0
-    return (a.score ?? 0) < max
-  })
-
-  if (wrongAnswers.length === 0) return 0
-
-  // 查询已存在的错题，避免重复
-  const existing = await db
-    .select({ questionId: errorBookItems.questionId })
-    .from(errorBookItems)
-    .where(
-      and(
-        eq(errorBookItems.studentId, studentId),
-        inArray(
-          errorBookItems.questionId,
-          wrongAnswers.map((a) => a.questionId)
-        )
-      )
-    )
-  const existingSet = new Set(existing.map((e) => e.questionId))
-
-  // 查询题目关联的知识点
-  const kpRows = await db
-    .select({
-      questionId: questionsToKnowledgePoints.questionId,
-      knowledgePointId: questionsToKnowledgePoints.knowledgePointId,
-    })
-    .from(questionsToKnowledgePoints)
-    .where(
-      inArray(
-        questionsToKnowledgePoints.questionId,
-        wrongAnswers.map((a) => a.questionId)
-      )
-    )
-  const kpMap = new Map<string, string[]>()
-  for (const kp of kpRows) {
-    const list = kpMap.get(kp.questionId) ?? []
-    list.push(kp.knowledgePointId)
-    kpMap.set(kp.questionId, list)
-  }
-
-  // 批量插入
-  const now = new Date()
-  const toInsert = wrongAnswers
-    .filter((a) => !existingSet.has(a.questionId))
-    .map((a) => ({
-      id: createId(),
-      studentId,
-      questionId: a.questionId,
-      sourceType: "exam" as const,
-      sourceId: submissionId,
-      studentAnswer: a.answerContent,
-      correctAnswer: null,
-      subjectId: null,
-      knowledgePointIds: kpMap.get(a.questionId) ?? null,
-      status: "new" as const,
-      masteryLevel: 0,
-      nextReviewAt: now,
-      reviewInterval: 1,
-      reviewCount: 0,
-      correctStreak: 0,
-      note: a.feedback ?? null,
-      errorTags: null,
-    }))
-
-  if (toInsert.length > 0) {
-    await db.insert(errorBookItems).values(toInsert)
-  }
-
-  return toInsert.length
-}
-
-// ---------------------------------------------------------------------------
-// 自动采集：从作业提交中收集错题
-// ---------------------------------------------------------------------------
-
-export async function collectFromHomeworkSubmission(
-  submissionId: string,
-  studentId: string
-): Promise<number> {
-  const submission = await db.query.homeworkSubmissions.findFirst({
-    where: eq(homeworkSubmissions.id, submissionId),
-  })
-
-  if (!submission) throw new Error("作业提交记录不存在")
-
-  const answers = await db
-    .select({
-      answerId: homeworkAnswers.id,
-      questionId: homeworkAnswers.questionId,
-      answerContent: homeworkAnswers.answerContent,
-      score: homeworkAnswers.score,
-      feedback: homeworkAnswers.feedback,
-    })
-    .from(homeworkAnswers)
-    .where(eq(homeworkAnswers.submissionId, submissionId))
-
-  // 查询题目满分
-  const questionIds = answers.map((a) => a.questionId)
-  const hwQuestionScores = await db
-    .select({
-      questionId: homeworkAssignmentQuestions.questionId,
-      maxScore: homeworkAssignmentQuestions.score,
-    })
-    .from(homeworkAssignmentQuestions)
-    .where(
-      and(
-        eq(homeworkAssignmentQuestions.assignmentId, submission.assignmentId),
-        inArray(homeworkAssignmentQuestions.questionId, questionIds)
-      )
-    )
-
-  const maxScoreMap = new Map(hwQuestionScores.map((q) => [q.questionId, q.maxScore ?? 0]))
-
-  const wrongAnswers = answers.filter((a) => {
-    const max = maxScoreMap.get(a.questionId) ?? 0
-    return (a.score ?? 0) < max
-  })
-
-  if (wrongAnswers.length === 0) return 0
-
-  // 去重
-  const existing = await db
-    .select({ questionId: errorBookItems.questionId })
-    .from(errorBookItems)
-    .where(
-      and(
-        eq(errorBookItems.studentId, studentId),
-        inArray(
-          errorBookItems.questionId,
-          wrongAnswers.map((a) => a.questionId)
-        )
-      )
-    )
-  const existingSet = new Set(existing.map((e) => e.questionId))
-
-  // 查询知识点
-  const kpRows = await db
-    .select({
-      questionId: questionsToKnowledgePoints.questionId,
-      knowledgePointId: questionsToKnowledgePoints.knowledgePointId,
-    })
-    .from(questionsToKnowledgePoints)
-    .where(
-      inArray(
-        questionsToKnowledgePoints.questionId,
-        wrongAnswers.map((a) => a.questionId)
-      )
-    )
-  const kpMap = new Map<string, string[]>()
-  for (const kp of kpRows) {
-    const list = kpMap.get(kp.questionId) ?? []
-    list.push(kp.knowledgePointId)
-    kpMap.set(kp.questionId, list)
-  }
-
-  const now = new Date()
-  const toInsert = wrongAnswers
-    .filter((a) => !existingSet.has(a.questionId))
-    .map((a) => ({
-      id: createId(),
-      studentId,
-      questionId: a.questionId,
-      sourceType: "homework" as const,
-      sourceId: submissionId,
-      studentAnswer: a.answerContent,
-      correctAnswer: null,
-      subjectId: null,
-      knowledgePointIds: kpMap.get(a.questionId) ?? null,
-      status: "new" as const,
-      masteryLevel: 0,
-      nextReviewAt: now,
-      reviewInterval: 1,
-      reviewCount: 0,
-      correctStreak: 0,
-      note: a.feedback ?? null,
-      errorTags: null,
-    }))
-
-  if (toInsert.length > 0) {
-    await db.insert(errorBookItems).values(toInsert)
-  }
-
-  return toInsert.length
-}
+export {
+  collectFromExamSubmission,
+  collectFromHomeworkSubmission,
+} from "./data-access-collection"
 
 // ---------------------------------------------------------------------------
 // 跨模块查询接口：供教师/家长视图使用
 // ---------------------------------------------------------------------------
 
-/** 查询多个学生的错题统计（教师视图） */
+/** 构建学生错题查询的 where 条件（支持按学科过滤） */
+function buildStudentErrorWhereClause(
+  studentIds: string[],
+  subjectId?: string | null
+): SQL | undefined {
+  const conditions: SQL[] = [inArray(errorBookItems.studentId, studentIds)]
+  if (subjectId) {
+    conditions.push(eq(errorBookItems.subjectId, subjectId))
+  }
+  return and(...conditions)
+}
+
+/** 查询多个学生的错题统计（教师视图，支持按学科过滤） */
 export async function getStudentErrorBookSummaries(
-  studentIds: string[]
-): Promise<Array<{
-  studentId: string
-  totalCount: number
-  newCount: number
-  learningCount: number
-  masteredCount: number
-  dueReviewCount: number
-  masteredRate: number
-  lastActivityAt: Date | null
-}>> {
+  studentIds: string[],
+  subjectId?: string | null
+): Promise<StudentErrorBookSummary[]> {
   if (studentIds.length === 0) return []
 
   const now = new Date()
+  const whereClause = buildStudentErrorWhereClause(studentIds, subjectId)
+
   const rows = await db
     .select({
       studentId: errorBookItems.studentId,
@@ -697,7 +481,26 @@ export async function getStudentErrorBookSummaries(
       updatedAt: errorBookItems.updatedAt,
     })
     .from(errorBookItems)
-    .where(inArray(errorBookItems.studentId, studentIds))
+    .where(whereClause)
+
+  // 查询学生所属班级（用于按班级分组展示）
+  const enrollmentRows = await db
+    .select({
+      studentId: classEnrollments.studentId,
+      classId: classes.id,
+      className: classes.name,
+    })
+    .from(classEnrollments)
+    .innerJoin(classes, eq(classEnrollments.classId, classes.id))
+    .where(inArray(classEnrollments.studentId, studentIds))
+
+  const studentClassMap = new Map<string, { classId: string; className: string }>()
+  for (const row of enrollmentRows) {
+    // 取第一个班级（学生通常只属于一个班）
+    if (!studentClassMap.has(row.studentId)) {
+      studentClassMap.set(row.studentId, { classId: row.classId, className: row.className })
+    }
+  }
 
   const map = new Map<string, {
     totalCount: number
@@ -736,17 +539,23 @@ export async function getStudentErrorBookSummaries(
     map.set(row.studentId, stat)
   }
 
-  return Array.from(map.entries()).map(([studentId, stat]) => ({
+  return Array.from(map.entries()).map(([studentId, stat]) => {
+    const classInfo = studentClassMap.get(studentId)
+    return {
       studentId,
       ...stat,
       masteredRate: stat.totalCount > 0 ? stat.masteredCount / stat.totalCount : 0,
-  }))
+      classId: classInfo?.classId ?? null,
+      className: classInfo?.className ?? null,
+    }
+  })
 }
 
-/** 查询班级内错题最多的题目（教师视图：高频错题） */
+/** 查询班级内错题最多的题目（教师视图：高频错题，支持按学科过滤） */
 export async function getTopWrongQuestionsByStudentIds(
   studentIds: string[],
-  limit = 10
+  limit = 10,
+  subjectId?: string | null
 ): Promise<Array<{
   questionId: string
   questionContent: unknown
@@ -756,6 +565,8 @@ export async function getTopWrongQuestionsByStudentIds(
 }>> {
   if (studentIds.length === 0) return []
 
+  const whereClause = buildStudentErrorWhereClause(studentIds, subjectId)
+
   const rows = await db
     .select({
       questionId: errorBookItems.questionId,
@@ -765,7 +576,7 @@ export async function getTopWrongQuestionsByStudentIds(
     })
     .from(errorBookItems)
     .innerJoin(questions, eq(questions.id, errorBookItems.questionId))
-    .where(inArray(errorBookItems.studentId, studentIds))
+    .where(whereClause)
 
   const map = new Map<string, { questionContent: unknown; questionType: string; errorCount: number; masteredCount: number }>()
 
@@ -816,23 +627,19 @@ export async function getAllStudentIds(): Promise<string[]> {
 }
 
 // ---------------------------------------------------------------------------
-// 统计：知识点薄弱度 & 学科分布（教师/管理员视图）
+// 统计：知识点薄弱度 & 学科分布 & 章节维度（教师/管理员视图）
 // ---------------------------------------------------------------------------
 
-/** 查询多个学生的知识点薄弱度统计 */
+/** 查询多个学生的知识点薄弱度统计（支持按学科过滤，关联章节信息） */
 export async function getKnowledgePointWeakness(
   studentIds: string[],
-  limit = 10
-): Promise<Array<{
-  knowledgePointId: string
-  knowledgePointName: string
-  errorCount: number
-  masteredCount: number
-  totalCount: number
-  masteryRate: number
-}>> {
+  limit = 10,
+  subjectId?: string | null
+): Promise<KnowledgePointWeakness[]> {
   if (studentIds.length === 0) return []
 
+  const whereClause = buildStudentErrorWhereClause(studentIds, subjectId)
+
   // 查询这些学生的所有错题条目（含知识点）
   const rows = await db
     .select({
@@ -841,7 +648,7 @@ export async function getKnowledgePointWeakness(
       knowledgePointIds: errorBookItems.knowledgePointIds,
     })
     .from(errorBookItems)
-    .where(inArray(errorBookItems.studentId, studentIds))
+    .where(whereClause)
 
   // 展开知识点并统计
   const kpMap = new Map<string, { errorCount: number; masteredCount: number }>()
@@ -858,23 +665,45 @@ export async function getKnowledgePointWeakness(
 
   if (kpMap.size === 0) return []
 
-  // 查询知识点名称
+  // 查询知识点名称及所属章节
   const kpIds = Array.from(kpMap.keys())
   const kpRows = await db
-    .select({ id: knowledgePoints.id, name: knowledgePoints.name })
+    .select({
+      id: knowledgePoints.id,
+      name: knowledgePoints.name,
+      chapterId: knowledgePoints.chapterId,
+    })
     .from(knowledgePoints)
     .where(inArray(knowledgePoints.id, kpIds))
-  const kpNameMap = new Map(kpRows.map((k) => [k.id, k.name]))
+  const kpInfoMap = new Map(kpRows.map((k) => [k.id, { name: k.name, chapterId: k.chapterId }]))
+
+  // 查询章节标题
+  const chapterIds = Array.from(new Set(
+    kpRows.map((k) => k.chapterId).filter((c): c is string => c !== null)
+  ))
+  let chapterTitleMap = new Map<string, string>()
+  if (chapterIds.length > 0) {
+    const chapterRows = await db
+      .select({ id: chapters.id, title: chapters.title })
+      .from(chapters)
+      .where(inArray(chapters.id, chapterIds))
+    chapterTitleMap = new Map(chapterRows.map((c) => [c.id, c.title]))
+  }
 
   return Array.from(kpMap.entries())
-    .map(([kpId, stat]) => ({
+    .map(([kpId, stat]) => {
+      const info = kpInfoMap.get(kpId)
+      return {
         knowledgePointId: kpId,
-      knowledgePointName: kpNameMap.get(kpId) ?? "未知知识点",
+        knowledgePointName: info?.name ?? "未知知识点",
         errorCount: stat.errorCount,
         masteredCount: stat.masteredCount,
         totalCount: stat.errorCount,
         masteryRate: stat.errorCount > 0 ? stat.masteredCount / stat.errorCount : 0,
-    }))
+        chapterId: info?.chapterId ?? null,
+        chapterTitle: info?.chapterId ? (chapterTitleMap.get(info.chapterId) ?? null) : null,
+      }
+    })
     .sort((a, b) => {
       // 按错误数降序，掌握率升序（最薄弱的在前）
       if (b.errorCount !== a.errorCount) return b.errorCount - a.errorCount
@@ -933,6 +762,262 @@ export async function getSubjectErrorDistribution(
   }))
 }
 
+/**
+ * 查询章节薄弱度统计（哪些课在错）。
+ * 通过 errorBookItems.knowledgePointIds → knowledgePoints.chapterId → chapters 关联。
+ * 支持按学科过滤（通过 errorBookItems.subjectId）。
+ */
+export async function getChapterWeakness(
+  studentIds: string[],
+  limit = 10,
+  subjectId?: string | null
+): Promise<ChapterWeakness[]> {
+  if (studentIds.length === 0) return []
+
+  const whereClause = buildStudentErrorWhereClause(studentIds, subjectId)
+
+  // 查询错题条目（含知识点和状态）
+  const rows = await db
+    .select({
+      itemId: errorBookItems.id,
+      status: errorBookItems.status,
+      knowledgePointIds: errorBookItems.knowledgePointIds,
+    })
+    .from(errorBookItems)
+    .where(whereClause)
+
+  // 展开知识点，建立 kpId → 错题统计
+  const kpErrorMap = new Map<string, { errorCount: number; masteredCount: number }>()
+  for (const row of rows) {
+    const kps = (row.knowledgePointIds as string[] | null) ?? []
+    for (const kpId of kps) {
+      const stat = kpErrorMap.get(kpId) ?? { errorCount: 0, masteredCount: 0 }
+      stat.errorCount++
+      if (toStatus(row.status) === "mastered") stat.masteredCount++
+      kpErrorMap.set(kpId, stat)
+    }
+  }
+
+  if (kpErrorMap.size === 0) return []
+
+  // 查询知识点 → 章节映射
+  const kpIds = Array.from(kpErrorMap.keys())
+  const kpRows = await db
+    .select({
+      id: knowledgePoints.id,
+      name: knowledgePoints.name,
+      chapterId: knowledgePoints.chapterId,
+    })
+    .from(knowledgePoints)
+    .where(inArray(knowledgePoints.id, kpIds))
+
+  // 按章节聚合
+  const chapterMap = new Map<string, {
+    errorCount: number
+    masteredCount: number
+    knowledgePointCount: number
+    topKps: Array<{ knowledgePointId: string; knowledgePointName: string; errorCount: number }>
+  }>()
+
+  for (const kp of kpRows) {
+    if (!kp.chapterId) continue
+    const kpStat = kpErrorMap.get(kp.id)
+    if (!kpStat) continue
+
+    const chapterStat = chapterMap.get(kp.chapterId) ?? {
+      errorCount: 0,
+      masteredCount: 0,
+      knowledgePointCount: 0,
+      topKps: [],
+    }
+    chapterStat.errorCount += kpStat.errorCount
+    chapterStat.masteredCount += kpStat.masteredCount
+    chapterStat.knowledgePointCount++
+    chapterStat.topKps.push({
+      knowledgePointId: kp.id,
+      knowledgePointName: kp.name,
+      errorCount: kpStat.errorCount,
+    })
+    chapterMap.set(kp.chapterId, chapterStat)
+  }
+
+  if (chapterMap.size === 0) return []
+
+  // 查询章节标题
+  const chapterIds = Array.from(chapterMap.keys())
+  const chapterRows = await db
+    .select({ id: chapters.id, title: chapters.title })
+    .from(chapters)
+    .where(inArray(chapters.id, chapterIds))
+  const chapterTitleMap = new Map(chapterRows.map((c) => [c.id, c.title]))
+
+  return Array.from(chapterMap.entries())
+    .map(([chapterId, stat]) => ({
+      chapterId,
+      chapterTitle: chapterTitleMap.get(chapterId) ?? "未知章节",
+      errorCount: stat.errorCount,
+      masteredCount: stat.masteredCount,
+      knowledgePointCount: stat.knowledgePointCount,
+      masteryRate: stat.errorCount > 0 ? stat.masteredCount / stat.errorCount : 0,
+      topKnowledgePoints: stat.topKps
+        .sort((a, b) => b.errorCount - a.errorCount)
+        .slice(0, 3),
+    }))
+    .sort((a, b) => b.errorCount - a.errorCount)
+    .slice(0, limit)
+}
+
+/**
+ * 查询按班级分组的错题概览（教师视图：分班显示）。
+ * 对每个班级统计：学生数、错题总数、人均错题数、平均掌握率、待复习数。
+ * 支持按学科过滤。
+ */
+export async function getClassErrorOverviews(
+  classIds: string[],
+  subjectId?: string | null
+): Promise<ClassErrorOverview[]> {
+  if (classIds.length === 0) return []
+
+  // 查询每个班级的学生
+  const enrollmentRows = await db
+    .select({
+      classId: classEnrollments.classId,
+      studentId: classEnrollments.studentId,
+      className: classes.name,
+    })
+    .from(classEnrollments)
+    .innerJoin(classes, eq(classEnrollments.classId, classes.id))
+    .where(inArray(classEnrollments.classId, classIds))
+
+  const classStudentMap = new Map<string, { className: string; studentIds: Set<string> }>()
+  for (const row of enrollmentRows) {
+    const entry = classStudentMap.get(row.classId) ?? { className: row.className, studentIds: new Set<string>() }
+    entry.studentIds.add(row.studentId)
+    classStudentMap.set(row.classId, entry)
+  }
+
+  // 查询所有相关学生的错题
+  const allStudentIds = Array.from(new Set(enrollmentRows.map((r) => r.studentId)))
+  if (allStudentIds.length === 0) return []
+
+  const whereClause = buildStudentErrorWhereClause(allStudentIds, subjectId)
+  const errorRows = await db
+    .select({
+      studentId: errorBookItems.studentId,
+      status: errorBookItems.status,
+      nextReviewAt: errorBookItems.nextReviewAt,
+    })
+    .from(errorBookItems)
+    .where(whereClause)
+
+  const now = new Date()
+  // 按学生聚合
+  const studentStatMap = new Map<string, { total: number; mastered: number; due: number }>()
+  for (const row of errorRows) {
+    const stat = studentStatMap.get(row.studentId) ?? { total: 0, mastered: 0, due: 0 }
+    stat.total++
+    const status = toStatus(row.status)
+    if (status === "mastered") stat.mastered++
+    if (status !== "mastered" && status !== "archived") {
+      if (!row.nextReviewAt || row.nextReviewAt <= now) stat.due++
+    }
+    studentStatMap.set(row.studentId, stat)
+  }
+
+  // 按班级聚合
+  return Array.from(classStudentMap.entries()).map(([classId, entry]) => {
+    const studentIds = Array.from(entry.studentIds)
+    let totalError = 0
+    let totalMastered = 0
+    let totalDue = 0
+    for (const sid of studentIds) {
+      const stat = studentStatMap.get(sid)
+      if (stat) {
+        totalError += stat.total
+        totalMastered += stat.mastered
+        totalDue += stat.due
+      }
+    }
+    return {
+      classId,
+      className: entry.className,
+      studentCount: studentIds.length,
+      totalErrorItems: totalError,
+      averageErrorPerStudent: studentIds.length > 0 ? totalError / studentIds.length : 0,
+      averageMasteryRate: totalError > 0 ? totalMastered / totalError : 0,
+      dueReviewCount: totalDue,
+    }
+  }).sort((a, b) => b.totalErrorItems - a.totalErrorItems)
+}
+
+/**
+ * 查询按学科分组的错题概览（用于学科 Tab 展示）。
+ * 返回每个学科的错题总数、涉及学生数、平均掌握率、待复习数。
+ */
+export async function getSubjectErrorOverviews(
+  studentIds: string[]
+): Promise<SubjectErrorOverview[]> {
+  if (studentIds.length === 0) return []
+
+  const rows = await db
+    .select({
+      subjectId: errorBookItems.subjectId,
+      studentId: errorBookItems.studentId,
+      status: errorBookItems.status,
+      nextReviewAt: errorBookItems.nextReviewAt,
+    })
+    .from(errorBookItems)
+    .where(inArray(errorBookItems.studentId, studentIds))
+
+  const now = new Date()
+  const subjectMap = new Map<string, {
+    totalErrorItems: number
+    masteredCount: number
+    dueReviewCount: number
+    studentSet: Set<string>
+  }>()
+
+  for (const row of rows) {
+    const key = row.subjectId
+    if (!key) continue // 跳过无学科的错题
+    const stat = subjectMap.get(key) ?? {
+      totalErrorItems: 0,
+      masteredCount: 0,
+      dueReviewCount: 0,
+      studentSet: new Set<string>(),
+    }
+    stat.totalErrorItems++
+    stat.studentSet.add(row.studentId)
+    const status = toStatus(row.status)
+    if (status === "mastered") stat.masteredCount++
+    if (status !== "mastered" && status !== "archived") {
+      if (!row.nextReviewAt || row.nextReviewAt <= now) stat.dueReviewCount++
+    }
+    subjectMap.set(key, stat)
+  }
+
+  if (subjectMap.size === 0) return []
+
+  // 查询学科名称
+  const subjectIds = Array.from(subjectMap.keys())
+  const subjectRows = await db
+    .select({ id: subjects.id, name: subjects.name })
+    .from(subjects)
+    .where(inArray(subjects.id, subjectIds))
+  const subjectNameMap = new Map(subjectRows.map((s) => [s.id, s.name]))
+
+  return Array.from(subjectMap.entries())
+    .map(([sid, stat]) => ({
+      subjectId: sid,
+      subjectName: subjectNameMap.get(sid) ?? "未知学科",
+      totalErrorItems: stat.totalErrorItems,
+      studentCount: stat.studentSet.size,
+      averageMasteryRate: stat.totalErrorItems > 0 ? stat.masteredCount / stat.totalErrorItems : 0,
+      dueReviewCount: stat.dueReviewCount,
+    }))
+    .sort((a, b) => b.totalErrorItems - a.totalErrorItems)
+}
+
 /** 查询学生姓名映射 */
 export async function getStudentNameMap(studentIds: string[]): Promise<Map<string, string>> {
   if (studentIds.length === 0) return new Map()

src/modules/error-book/types.ts

@@ -152,6 +152,10 @@ export interface KnowledgePointWeakness {
   totalCount: number
   /** 掌握率 0-1 */
   masteryRate: number
+  /** 所属章节 ID（增强：关联章节维度） */
+  chapterId: string | null
+  /** 所属章节标题 */
+  chapterTitle: string | null
 }
 
 /** 学科错题分布 */
@@ -173,6 +177,10 @@ export interface StudentErrorBookSummary {
   dueReviewCount: number
   masteredRate: number
   lastActivityAt: Date | null
+  /** 所属班级 ID（增强：支持按班级分组展示） */
+  classId: string | null
+  /** 所属班级名称 */
+  className: string | null
 }
 
 /** 班级错题统计（教师视图） */
@@ -187,6 +195,47 @@ export interface ClassErrorBookStats {
   topStudents: StudentErrorBookSummary[]
 }
 
+/** 章节薄弱度统计（哪些课在错） */
+export interface ChapterWeakness {
+  chapterId: string
+  chapterTitle: string
+  /** 该章节下的错题总数 */
+  errorCount: number
+  /** 该章节下已掌握的错题数 */
+  masteredCount: number
+  /** 该章节下涉及的知识点数 */
+  knowledgePointCount: number
+  /** 掌握率 0-1 */
+  masteryRate: number
+  /** 该章节下错得最多的知识点（前 3 个） */
+  topKnowledgePoints: Array<{
+    knowledgePointId: string
+    knowledgePointName: string
+    errorCount: number
+  }>
+}
+
+/** 班级错题概览（按班级分组统计） */
+export interface ClassErrorOverview {
+  classId: string
+  className: string
+  studentCount: number
+  totalErrorItems: number
+  averageErrorPerStudent: number
+  averageMasteryRate: number
+  dueReviewCount: number
+}
+
+/** 学科错题概览（按学科分组统计，用于学科 Tab） */
+export interface SubjectErrorOverview {
+  subjectId: string
+  subjectName: string
+  totalErrorItems: number
+  studentCount: number
+  averageMasteryRate: number
+  dueReviewCount: number
+}
+
 /** 错题趋势数据点 */
 export interface ErrorBookTrendPoint {
   date: string