feat(diagnostic): add export, stats service, and confidence utils

- Add export module for diagnostic report data export

- Add stats-service for diagnostic analytics aggregation

- Add confidence-utils for diagnostic confidence score calculations

src/modules/diagnostic/components/class-diagnostic-view.tsx

@@ -4,7 +4,8 @@ import { useState } from "react"
 import Link from "next/link"
 import { useRouter } from "next/navigation"
 import { toast } from "sonner"
-import { Users, AlertTriangle, TrendingUp, FileText } from "lucide-react"
+import { useTranslations } from "next-intl"
+import { Users, AlertTriangle, TrendingUp, FileText, Filter } from "lucide-react"
 
 import { Card, CardContent, CardHeader, CardTitle, CardDescription } from "@/shared/components/ui/card"
 import { Badge } from "@/shared/components/ui/badge"
@@ -12,6 +13,13 @@ import { Button } from "@/shared/components/ui/button"
 import { Input } from "@/shared/components/ui/input"
 import { Label } from "@/shared/components/ui/label"
 import { EmptyState } from "@/shared/components/ui/empty-state"
+import {
+  Select,
+  SelectContent,
+  SelectItem,
+  SelectTrigger,
+  SelectValue,
+} from "@/shared/components/ui/select"
 import {
   Table,
   TableBody,
@@ -22,7 +30,7 @@ import {
 } from "@/shared/components/ui/table"
 import { usePermission } from "@/shared/hooks"
 import { Permissions } from "@/shared/types/permissions"
-import { generateClassReportAction } from "../actions"
+import { generateClassReportAction, getClassStudentsByKnowledgePointAction } from "../actions"
 import type { ClassMasterySummary } from "../types"
 
 interface ClassDiagnosticViewProps {
@@ -37,13 +45,29 @@ function masteryColor(level: number): string {
   return "bg-red-500"
 }
 
+type KnowledgePointStudent = {
+  studentId: string
+  studentName: string
+  masteryLevel: number
+  totalQuestions: number
+  correctQuestions: number
+  lastAssessedAt: string | null
+  needsAttention: boolean
+}
+
 export function ClassDiagnosticView({ summary }: ClassDiagnosticViewProps) {
+  const t = useTranslations("diagnostic")
   const router = useRouter()
   const { hasPermission } = usePermission()
   const canManage = hasPermission(Permissions.DIAGNOSTIC_MANAGE)
   const [period, setPeriod] = useState(new Date().toISOString().slice(0, 7))
   const [isGenerating, setIsGenerating] = useState(false)
 
+  // v3-P2-5: 知识点筛选状态
+  const [selectedKpId, setSelectedKpId] = useState<string>("all")
+  const [filteredStudents, setFilteredStudents] = useState<KnowledgePointStudent[] | null>(null)
+  const [isFiltering, setIsFiltering] = useState(false)
+
   const handleGenerate = async () => {
     if (!summary) return
     setIsGenerating(true)
@@ -56,15 +80,45 @@ export function ClassDiagnosticView({ summary }: ClassDiagnosticViewProps) {
       toast.success(result.message)
       router.refresh()
     } else {
-      toast.error(result.message || "Failed to generate class report")
+      toast.error(result.message || t("error.generateClassFailed"))
+    }
+  }
+
+  /**
+   * v3-P2-5: 按知识点筛选学生。
+   * 选择知识点后调用 server action 获取该知识点上所有学生的掌握度。
+   */
+  const handleKpFilter = async (kpId: string) => {
+    setSelectedKpId(kpId)
+    if (!summary || kpId === "all") {
+      setFilteredStudents(null)
+      return
+    }
+    setIsFiltering(true)
+    try {
+      const result = await getClassStudentsByKnowledgePointAction({
+        classId: summary.classId,
+        knowledgePointId: kpId,
+      })
+      if (result.success && result.data) {
+        setFilteredStudents(result.data)
+      } else {
+        toast.error(result.message || t("error.loadFailed"))
+        setFilteredStudents(null)
+      }
+    } catch {
+      toast.error(t("error.loadFailed"))
+      setFilteredStudents(null)
+    } finally {
+      setIsFiltering(false)
     }
   }
 
   if (!summary) {
     return (
       <EmptyState
-        title="No class data"
-        description="Unable to load class mastery summary."
+        title={t("classDiagnostic.noClassDataTitle")}
+        description={t("empty.noClassData")}
         icon={Users}
         className="border-none shadow-none"
       />
@@ -77,7 +131,7 @@ export function ClassDiagnosticView({ summary }: ClassDiagnosticViewProps) {
       <div className="grid grid-cols-1 gap-4 md:grid-cols-4">
         <Card>
           <CardHeader className="pb-2">
-            <CardTitle className="text-sm font-medium text-muted-foreground">Class</CardTitle>
+            <CardTitle className="text-sm font-medium text-muted-foreground">{t("summary.class")}</CardTitle>
           </CardHeader>
           <CardContent>
             <p className="text-2xl font-bold">{summary.className}</p>
@@ -85,7 +139,7 @@ export function ClassDiagnosticView({ summary }: ClassDiagnosticViewProps) {
         </Card>
         <Card>
           <CardHeader className="pb-2">
-            <CardTitle className="text-sm font-medium text-muted-foreground">Students</CardTitle>
+            <CardTitle className="text-sm font-medium text-muted-foreground">{t("summary.students")}</CardTitle>
           </CardHeader>
           <CardContent>
             <p className="text-2xl font-bold">{summary.studentCount}</p>
@@ -93,7 +147,7 @@ export function ClassDiagnosticView({ summary }: ClassDiagnosticViewProps) {
         </Card>
         <Card>
           <CardHeader className="pb-2">
-            <CardTitle className="text-sm font-medium text-muted-foreground">Avg Mastery</CardTitle>
+            <CardTitle className="text-sm font-medium text-muted-foreground">{t("summary.avgMastery")}</CardTitle>
           </CardHeader>
           <CardContent>
             <p className="text-2xl font-bold">{summary.averageMastery.toFixed(1)}%</p>
@@ -101,7 +155,7 @@ export function ClassDiagnosticView({ summary }: ClassDiagnosticViewProps) {
         </Card>
         <Card>
           <CardHeader className="pb-2">
-            <CardTitle className="text-sm font-medium text-muted-foreground">Need Attention</CardTitle>
+            <CardTitle className="text-sm font-medium text-muted-foreground">{t("summary.needAttention")}</CardTitle>
           </CardHeader>
           <CardContent>
             <p className="text-2xl font-bold text-red-600">{summary.studentsNeedingAttention.length}</p>
@@ -114,70 +168,194 @@ export function ClassDiagnosticView({ summary }: ClassDiagnosticViewProps) {
         <CardHeader>
           <CardTitle className="flex items-center gap-2">
             <TrendingUp className="h-4 w-4" />
-            Knowledge Point Mastery Heatmap
+            {t("chart.heatmapTitle")}
           </CardTitle>
           <CardDescription>
-            Average mastery level per knowledge point (green ≥80%, yellow 60-79%, orange 40-59%, red &lt;40%).
+            {t("classDiagnostic.heatmapDescription")}
           </CardDescription>
         </CardHeader>
         <CardContent>
           {summary.knowledgePointStats.length === 0 ? (
-            <p className="text-sm text-muted-foreground">No knowledge point data available.</p>
+            <p className="text-sm text-muted-foreground">{t("classDiagnostic.noKnowledgePointData")}</p>
           ) : (
-            <div className="flex flex-wrap gap-2">
-              {summary.knowledgePointStats.map((kp) => (
-                <div
-                  key={kp.knowledgePointId}
-                  className={`flex flex-col items-center justify-center rounded-md px-3 py-2 text-white ${masteryColor(kp.averageMastery)}`}
-                  title={`${kp.knowledgePointName}: ${kp.averageMastery.toFixed(1)}% (mastered ${kp.masteredCount}/${kp.totalStudents})`}
-                >
-                  <span className="max-w-32 truncate text-xs font-medium">
-                    {kp.knowledgePointName}
-                  </span>
-                  <span className="text-sm font-bold">{kp.averageMastery.toFixed(0)}%</span>
+            <>
+              <div
+                className="flex flex-wrap gap-2"
+                role="img"
+                aria-label={t("classDiagnostic.heatmapAriaLabel", { count: summary.knowledgePointStats.length })}
+              >
+                {summary.knowledgePointStats.map((kp) => {
+                  const levelLabel = kp.averageMastery >= 80 ? t("classDiagnostic.masteryLevelExcellent") : kp.averageMastery >= 60 ? t("classDiagnostic.masteryLevelGood") : kp.averageMastery >= 40 ? t("classDiagnostic.masteryLevelNeedsImprovement") : t("classDiagnostic.masteryLevelWeak")
+                  return (
+                    <div
+                      key={kp.knowledgePointId}
+                      className={`flex flex-col items-center justify-center rounded-md px-3 py-2 text-white ${masteryColor(kp.averageMastery)}`}
+                      role="img"
+                      aria-label={`${kp.knowledgePointName}：${kp.averageMastery.toFixed(1)}%，${levelLabel}，${kp.masteredCount}/${kp.totalStudents}`}
+                      title={`${kp.knowledgePointName}: ${kp.averageMastery.toFixed(1)}% (${kp.masteredCount}/${kp.totalStudents})`}
+                    >
+                      <span className="max-w-32 truncate text-xs font-medium">
+                        {kp.knowledgePointName}
+                      </span>
+                      <span className="text-sm font-bold">{kp.averageMastery.toFixed(0)}%</span>
+                    </div>
+                  )
+                })}
+              </div>
+              {/* v4-P1-8: 热力图颜色图例 */}
+              <div className="mt-4 flex flex-wrap items-center gap-3 border-t pt-3">
+                <span className="text-xs font-medium text-muted-foreground">
+                  {t("classDiagnostic.legendLabel")}
+                </span>
+                <div className="flex flex-wrap items-center gap-3 text-xs">
+                  <div className="flex items-center gap-1.5">
+                    <span className="inline-block h-3 w-3 rounded-sm bg-green-500" aria-hidden="true" />
+                    <span>{t("classDiagnostic.masteryLevelExcellent")} (≥80%)</span>
+                  </div>
+                  <div className="flex items-center gap-1.5">
+                    <span className="inline-block h-3 w-3 rounded-sm bg-yellow-500" aria-hidden="true" />
+                    <span>{t("classDiagnostic.masteryLevelGood")} (60-79%)</span>
+                  </div>
+                  <div className="flex items-center gap-1.5">
+                    <span className="inline-block h-3 w-3 rounded-sm bg-orange-500" aria-hidden="true" />
+                    <span>{t("classDiagnostic.masteryLevelNeedsImprovement")} (40-59%)</span>
+                  </div>
+                  <div className="flex items-center gap-1.5">
+                    <span className="inline-block h-3 w-3 rounded-sm bg-red-500" aria-hidden="true" />
+                    <span>{t("classDiagnostic.masteryLevelWeak")} (&lt;40%)</span>
+                  </div>
                 </div>
-              ))}
-            </div>
+              </div>
+            </>
           )}
         </CardContent>
       </Card>
 
+      {/* v3-P2-5: 按知识点筛选学生 */}
+      <Card>
+        <CardHeader>
+          <CardTitle className="flex items-center gap-2">
+            <Filter className="h-4 w-4" />
+            {t("classDiagnostic.filterByKpTitle")}
+          </CardTitle>
+          <CardDescription>
+            {t("classDiagnostic.filterByKpDescription")}
+          </CardDescription>
+        </CardHeader>
+        <CardContent className="space-y-4">
+          <div className="grid gap-2">
+            <Label htmlFor="kp-filter" className="text-xs">
+              {t("classDiagnostic.kpFilterLabel")}
+            </Label>
+            <Select value={selectedKpId} onValueChange={handleKpFilter}>
+              <SelectTrigger id="kp-filter" className="w-full md:w-80">
+                <SelectValue placeholder={t("classDiagnostic.kpFilterPlaceholder")} />
+              </SelectTrigger>
+              <SelectContent>
+                <SelectItem value="all">{t("classDiagnostic.kpFilterAll")}</SelectItem>
+                {summary.knowledgePointStats.map((kp) => (
+                  <SelectItem key={kp.knowledgePointId} value={kp.knowledgePointId}>
+                    {kp.knowledgePointName} ({kp.averageMastery.toFixed(0)}%)
+                  </SelectItem>
+                ))}
+              </SelectContent>
+            </Select>
+          </div>
+
+          {isFiltering ? (
+            <p className="text-sm text-muted-foreground">{t("classDiagnostic.filtering")}</p>
+          ) : filteredStudents && filteredStudents.length > 0 ? (
+            <div className="rounded-md border">
+              {/* v4-P1-11: 移动端表格水平滚动 */}
+              <div className="overflow-x-auto">
+                <Table>
+                  <TableHeader>
+                    <TableRow>
+                      <TableHead>{t("summary.student")}</TableHead>
+                      <TableHead className="text-right">{t("classDiagnostic.avgMasteryColumn")}</TableHead>
+                      <TableHead className="text-right">{t("classDiagnostic.totalQuestionsColumn")}</TableHead>
+                      <TableHead className="text-right">{t("classDiagnostic.correctQuestionsColumn")}</TableHead>
+                      <TableHead>{t("classDiagnostic.statusColumn")}</TableHead>
+                      <TableHead></TableHead>
+                    </TableRow>
+                  </TableHeader>
+                  <TableBody>
+                    {filteredStudents.map((s) => (
+                      <TableRow key={s.studentId}>
+                        <TableCell className="font-medium">{s.studentName}</TableCell>
+                        <TableCell className="text-right font-mono">
+                          <Badge variant={s.masteryLevel >= 80 ? "default" : s.masteryLevel >= 60 ? "secondary" : "destructive"}>
+                            {s.masteryLevel.toFixed(0)}%
+                          </Badge>
+                        </TableCell>
+                        <TableCell className="text-right">{s.totalQuestions}</TableCell>
+                        <TableCell className="text-right">{s.correctQuestions}</TableCell>
+                        <TableCell>
+                          {s.needsAttention ? (
+                            <Badge variant="destructive">{t("classDiagnostic.needsAttention")}</Badge>
+                          ) : (
+                            <Badge variant="default">{t("classDiagnostic.mastered")}</Badge>
+                          )}
+                        </TableCell>
+                        <TableCell>
+                          <Button asChild variant="ghost" size="sm" aria-label={t("classDiagnostic.viewAriaLabel", { studentName: s.studentName })}>
+                            <Link href={`/teacher/diagnostic/student/${s.studentId}`}>
+                              <FileText className="mr-1 h-3 w-3" />
+                              {t("classDiagnostic.viewAction")}
+                            </Link>
+                          </Button>
+                        </TableCell>
+                      </TableRow>
+                    ))}
+                  </TableBody>
+                </Table>
+              </div>
+            </div>
+          ) : filteredStudents && filteredStudents.length === 0 ? (
+            <p className="text-sm text-muted-foreground">{t("classDiagnostic.noStudentsForKp")}</p>
+          ) : null}
+        </CardContent>
+      </Card>
+
       {/* 知识点排名表 */}
       <Card>
         <CardHeader>
-          <CardTitle>Knowledge Point Ranking</CardTitle>
+          <CardTitle>{t("chart.rankingTitle")}</CardTitle>
         </CardHeader>
         <CardContent>
           {summary.knowledgePointStats.length === 0 ? (
-            <p className="text-sm text-muted-foreground">No data.</p>
+            <p className="text-sm text-muted-foreground">{t("classDiagnostic.noRankingData")}</p>
           ) : (
             <div className="rounded-md border">
-              <Table>
-                <TableHeader>
-                  <TableRow>
-                    <TableHead>Knowledge Point</TableHead>
-                    <TableHead className="text-right">Avg Mastery</TableHead>
-                    <TableHead className="text-right">Mastered (≥80%)</TableHead>
-                    <TableHead className="text-right">Not Mastered (&lt;60%)</TableHead>
-                  </TableRow>
-                </TableHeader>
-                <TableBody>
-                  {[...summary.knowledgePointStats]
-                    .sort((a, b) => b.averageMastery - a.averageMastery)
-                    .map((kp) => (
-                      <TableRow key={kp.knowledgePointId}>
-                        <TableCell className="font-medium">{kp.knowledgePointName}</TableCell>
-                        <TableCell className="text-right font-mono">
-                          <Badge variant={kp.averageMastery >= 80 ? "default" : kp.averageMastery >= 60 ? "secondary" : "destructive"}>
-                            {kp.averageMastery.toFixed(1)}%
-                          </Badge>
-                        </TableCell>
-                        <TableCell className="text-right text-green-600">{kp.masteredCount}</TableCell>
-                        <TableCell className="text-right text-red-600">{kp.notMasteredCount}</TableCell>
-                      </TableRow>
-                    ))}
-                </TableBody>
-              </Table>
+              {/* v4-P1-11: 移动端表格水平滚动 */}
+              <div className="overflow-x-auto">
+                <Table>
+                  <TableHeader>
+                    <TableRow>
+                      <TableHead>{t("classDiagnostic.knowledgePointColumn")}</TableHead>
+                      <TableHead className="text-right">{t("classDiagnostic.avgMasteryColumn")}</TableHead>
+                      <TableHead className="text-right">{t("classDiagnostic.masteredColumn")}</TableHead>
+                      <TableHead className="text-right">{t("classDiagnostic.notMasteredColumn")}</TableHead>
+                    </TableRow>
+                  </TableHeader>
+                  <TableBody>
+                    {[...summary.knowledgePointStats]
+                      .sort((a, b) => b.averageMastery - a.averageMastery)
+                      .map((kp) => (
+                        <TableRow key={kp.knowledgePointId}>
+                          <TableCell className="font-medium">{kp.knowledgePointName}</TableCell>
+                          <TableCell className="text-right font-mono">
+                            <Badge variant={kp.averageMastery >= 80 ? "default" : kp.averageMastery >= 60 ? "secondary" : "destructive"}>
+                              {kp.averageMastery.toFixed(1)}%
+                            </Badge>
+                          </TableCell>
+                          <TableCell className="text-right text-green-600">{kp.masteredCount}</TableCell>
+                          <TableCell className="text-right text-red-600">{kp.notMasteredCount}</TableCell>
+                        </TableRow>
+                      ))}
+                  </TableBody>
+                </Table>
+              </div>
             </div>
           )}
         </CardContent>
@@ -188,44 +366,47 @@ export function ClassDiagnosticView({ summary }: ClassDiagnosticViewProps) {
         <CardHeader>
           <CardTitle className="flex items-center gap-2">
             <AlertTriangle className="h-4 w-4 text-red-600" />
-            Students Needing Attention (avg &lt;60%)
+            {t("classDiagnostic.studentsNeedingAttentionTitle")}
           </CardTitle>
-          <CardDescription>Students with low overall mastery.</CardDescription>
+          <CardDescription>{t("classDiagnostic.studentsNeedingAttentionDescription")}</CardDescription>
         </CardHeader>
         <CardContent>
           {summary.studentsNeedingAttention.length === 0 ? (
-            <p className="text-sm text-muted-foreground">All students are above the attention threshold.</p>
+            <p className="text-sm text-muted-foreground">{t("classDiagnostic.allStudentsAboveThreshold")}</p>
           ) : (
             <div className="rounded-md border">
-              <Table>
-                <TableHeader>
-                  <TableRow>
-                    <TableHead>Student</TableHead>
-                    <TableHead className="text-right">Avg Mastery</TableHead>
-                    <TableHead className="text-right">Weak Points</TableHead>
-                    <TableHead></TableHead>
-                  </TableRow>
-                </TableHeader>
-                <TableBody>
-                  {summary.studentsNeedingAttention.map((s) => (
-                    <TableRow key={s.studentId}>
-                      <TableCell className="font-medium">{s.studentName}</TableCell>
-                      <TableCell className="text-right">
-                        <Badge variant="destructive">{s.averageMastery.toFixed(1)}%</Badge>
-                      </TableCell>
-                      <TableCell className="text-right text-red-600">{s.weakCount}</TableCell>
-                      <TableCell>
-                        <Button asChild variant="ghost" size="sm">
-                          <Link href={`/teacher/diagnostic/student/${s.studentId}`}>
-                            <FileText className="mr-1 h-3 w-3" />
-                            View
-                          </Link>
-                        </Button>
-                      </TableCell>
+              {/* v4-P1-11: 移动端表格水平滚动 */}
+              <div className="overflow-x-auto">
+                <Table>
+                  <TableHeader>
+                    <TableRow>
+                      <TableHead>{t("summary.student")}</TableHead>
+                      <TableHead className="text-right">{t("classDiagnostic.avgMasteryColumn")}</TableHead>
+                      <TableHead className="text-right">{t("classDiagnostic.weakPointsColumn")}</TableHead>
+                      <TableHead></TableHead>
                     </TableRow>
-                  ))}
-                </TableBody>
-              </Table>
+                  </TableHeader>
+                  <TableBody>
+                    {summary.studentsNeedingAttention.map((s) => (
+                      <TableRow key={s.studentId}>
+                        <TableCell className="font-medium">{s.studentName}</TableCell>
+                        <TableCell className="text-right">
+                          <Badge variant="destructive">{s.averageMastery.toFixed(1)}%</Badge>
+                        </TableCell>
+                        <TableCell className="text-right text-red-600">{s.weakCount}</TableCell>
+                        <TableCell>
+                          <Button asChild variant="ghost" size="sm" aria-label={t("classDiagnostic.viewAriaLabel", { studentName: s.studentName })}>
+                            <Link href={`/teacher/diagnostic/student/${s.studentId}`}>
+                              <FileText className="mr-1 h-3 w-3" />
+                              {t("classDiagnostic.viewAction")}
+                            </Link>
+                          </Button>
+                        </TableCell>
+                      </TableRow>
+                    ))}
+                  </TableBody>
+                </Table>
+              </div>
             </div>
           )}
         </CardContent>
@@ -237,16 +418,16 @@ export function ClassDiagnosticView({ summary }: ClassDiagnosticViewProps) {
           <CardHeader>
             <CardTitle className="flex items-center gap-2">
               <FileText className="h-4 w-4" />
-              Generate Class Diagnostic Report
+              {t("report.generateClass")}
             </CardTitle>
             <CardDescription>
-              Generate a class-level diagnostic report with aggregated analysis.
+              {t("classDiagnostic.generateDescription")}
             </CardDescription>
           </CardHeader>
           <CardContent>
             <div className="flex items-end gap-3">
               <div className="grid gap-2">
-                <Label htmlFor="class-period" className="text-xs">Period (YYYY-MM)</Label>
+                <Label htmlFor="class-period" className="text-xs">{t("classDiagnostic.periodLabel")}</Label>
                 <Input
                   id="class-period"
                   type="month"
@@ -256,7 +437,7 @@ export function ClassDiagnosticView({ summary }: ClassDiagnosticViewProps) {
                 />
               </div>
               <Button onClick={handleGenerate} disabled={isGenerating}>
-                {isGenerating ? "Generating..." : "Generate Class Report"}
+                {isGenerating ? t("classDiagnostic.generating") : t("classDiagnostic.generateButton")}
               </Button>
             </div>
           </CardContent>

src/modules/diagnostic/components/confidence-utils.ts

@@ -0,0 +1,31 @@
+/**
+ * v4-P3-7: 诊断报告数据置信度工具。
+ *
+ * 置信度等级用于指示报告基于的数据量是否充足，帮助教师判断报告可信度。
+ * 提取到独立文件供 report-list 和 student-diagnostic-view 共享，避免重复定义。
+ */
+
+import type { DiagnosticReportWithDetails } from "../types"
+
+export type ConfidenceLevel = "high" | "medium" | "low" | "insufficient"
+
+/**
+ * 根据报告数据计算置信度。
+ * 简化方案：overallScore === null 表示无数据（insufficient），
+ * 否则视为高置信度（high）。
+ * 后续可扩展为基于 totalQuestions 等数据量字段的多级判断。
+ */
+export function getConfidenceLevel(report: DiagnosticReportWithDetails): ConfidenceLevel {
+  if (report.overallScore === null) return "insufficient"
+  return "high"
+}
+
+export const confidenceBadgeVariant: Record<
+  ConfidenceLevel,
+  "default" | "secondary" | "destructive" | "outline"
+> = {
+  high: "default",
+  medium: "secondary",
+  low: "destructive",
+  insufficient: "outline",
+}

src/modules/diagnostic/components/mastery-radar-chart.tsx

@@ -1,5 +1,6 @@
 "use client"
 
+import { useTranslations } from "next-intl"
 import { Target } from "lucide-react"
 
 import { ChartCardShell } from "@/shared/components/charts/chart-card-shell"
@@ -11,6 +12,7 @@ interface MasteryRadarChartProps {
 }
 
 export function MasteryRadarChart({ data }: MasteryRadarChartProps) {
+  const t = useTranslations("diagnostic")
   const isEmpty = !data || data.length === 0
 
   const chartData = isEmpty
@@ -25,17 +27,29 @@ export function MasteryRadarChart({ data }: MasteryRadarChartProps) {
 
   const hasClassAverage = !isEmpty && data.some((d) => d.classAverage !== undefined)
 
+  const ariaLabel = isEmpty
+    ? t("chart.radarAriaLabelEmpty")
+    : t("chart.radarAriaLabelNonEmpty", {
+        count: data.length,
+        withClassAverage: hasClassAverage ? t("chart.withClassAverage") : "",
+      })
+
   return (
     <ChartCardShell
-      title="Knowledge Point Mastery"
-      description="Radar chart of mastery level (0-100) across knowledge points."
+      title={t("chart.radarTitle")}
+      description={t("chart.radarDescriptionNonEmpty")}
       icon={Target}
       isEmpty={isEmpty}
-      emptyTitle="No mastery data"
-      emptyDescription="No knowledge point mastery records found for this student."
+      emptyTitle={t("chart.radarEmptyTitle")}
+      emptyDescription={t("chart.noMasteryDataForStudent")}
       emptyClassName="h-60"
     >
-      <div role="img" aria-label={`知识点掌握度雷达图：${isEmpty ? "暂无数据" : `共 ${data.length} 个知识点的掌握度${hasClassAverage ? "（含班级平均对比）" : ""}`}`}>
+      <div
+        role="img"
+        aria-label={ariaLabel}
+        tabIndex={0}
+        className="rounded-md focus-visible:outline-2 focus-visible:outline-offset-4 focus-visible:outline-ring"
+      >
         <ComparisonRadarChart
           data={chartData}
           angleKey="shortName"
@@ -48,7 +62,7 @@ export function MasteryRadarChart({ data }: MasteryRadarChartProps) {
           series={[
             {
               dataKey: "student",
-              name: "Student",
+              name: t("chart.studentSeries"),
               color: "hsl(var(--primary))",
               fillOpacity: 0.35,
               strokeWidth: 2,
@@ -56,7 +70,7 @@ export function MasteryRadarChart({ data }: MasteryRadarChartProps) {
             },
             {
               dataKey: "classAverage",
-              name: "Class Avg",
+              name: t("chart.classAvgSeries"),
               color: "hsl(var(--chart-2))",
               fillOpacity: 0.15,
               strokeWidth: 2,

src/modules/diagnostic/components/report-list.tsx

@@ -3,8 +3,9 @@
 import { useState } from "react"
 import { useRouter, useSearchParams } from "next/navigation"
 import { useCallback } from "react"
+import { useTranslations } from "next-intl"
 import { toast } from "sonner"
-import { FileText, Trash2, Send } from "lucide-react"
+import { FileText, Trash2, Send, Download, Share2, Copy } from "lucide-react"
 
 import { Badge } from "@/shared/components/ui/badge"
 import { Button } from "@/shared/components/ui/button"
@@ -33,17 +34,18 @@ import {
   DialogHeader,
   DialogTitle,
 } from "@/shared/components/ui/dialog"
+import { Input } from "@/shared/components/ui/input"
+import { Tooltip, TooltipContent, TooltipTrigger } from "@/shared/components/ui/tooltip"
 import { formatDate } from "@/shared/lib/utils"
 import { usePermission } from "@/shared/hooks"
 import { Permissions } from "@/shared/types/permissions"
-import { publishReportAction, deleteReportAction } from "../actions"
+import { publishReportAction, deleteReportAction, exportDiagnosticReportAction } from "../actions"
 import type { DiagnosticReportWithDetails } from "../types"
-
-const typeLabels: Record<string, string> = {
-  individual: "Individual",
-  class: "Class",
-  grade: "Grade",
-}
+import {
+  getConfidenceLevel,
+  confidenceBadgeVariant,
+  type ConfidenceLevel,
+} from "./confidence-utils"
 
 const statusColors: Record<string, "default" | "secondary" | "destructive" | "outline"> = {
   draft: "secondary",
@@ -59,10 +61,12 @@ export function ReportList({ reports }: ReportListProps) {
   const router = useRouter()
   const searchParams = useSearchParams()
   const { hasPermission } = usePermission()
+  const t = useTranslations("diagnostic")
   const canManage = hasPermission(Permissions.DIAGNOSTIC_MANAGE)
 
   const [deleteId, setDeleteId] = useState<string | null>(null)
   const [publishId, setPublishId] = useState<string | null>(null)
+  const [shareId, setShareId] = useState<string | null>(null)
   const [isBusy, setIsBusy] = useState(false)
 
   const updateParam = useCallback(
@@ -90,7 +94,7 @@ export function ReportList({ reports }: ReportListProps) {
       setPublishId(null)
       router.refresh()
     } else {
-      toast.error(result.message || "Failed to publish")
+      toast.error(result.message || t("error.publishFailed"))
     }
   }
 
@@ -106,42 +110,133 @@ export function ReportList({ reports }: ReportListProps) {
       setDeleteId(null)
       router.refresh()
     } else {
-      toast.error(result.message || "Failed to delete")
+      toast.error(result.message || t("error.deleteFailed"))
     }
   }
 
+  /**
+   * v3-P2-4: 导出诊断报告为 Excel。
+   * 调用 server action 获取 base64 buffer，前端转 Blob 下载。
+   */
+  const handleExport = async (reportId: string) => {
+    setIsBusy(true)
+    try {
+      const result = await exportDiagnosticReportAction(reportId)
+      if (!result.success || !result.data) {
+        toast.error(result.message || t("error.exportFailed"))
+        return
+      }
+      // base64 -> Blob -> 下载
+      const binaryString = atob(result.data.buffer)
+      const bytes = new Uint8Array(binaryString.length)
+      for (let i = 0; i < binaryString.length; i += 1) {
+        bytes[i] = binaryString.charCodeAt(i)
+      }
+      const blob = new Blob([bytes], {
+        type: "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
+      })
+      const url = URL.createObjectURL(blob)
+      const a = document.createElement("a")
+      a.href = url
+      a.download = result.data.filename
+      document.body.appendChild(a)
+      a.click()
+      document.body.removeChild(a)
+      URL.revokeObjectURL(url)
+      toast.success(t("reportList.exportSuccess"))
+    } catch {
+      toast.error(t("error.exportFailed"))
+    } finally {
+      setIsBusy(false)
+    }
+  }
+
+  // v3-P3-8: 复制报告分享链接到剪贴板
+  const handleCopyLink = async (): Promise<void> => {
+    if (!shareId) return
+    const url = `${window.location.origin}/teacher/diagnostic/reports/${shareId}`
+    try {
+      await navigator.clipboard.writeText(url)
+      toast.success(t("reportList.copyLinkSuccess"))
+    } catch {
+      toast.error(t("reportList.copyLinkFailed"))
+    }
+  }
+
+  // v4-P3-7: 置信度标签与提示
+  const confidenceLabel = (level: ConfidenceLevel): string => {
+    if (level === "high") return t("reportList.confidenceHigh")
+    if (level === "medium") return t("reportList.confidenceMedium")
+    if (level === "low") return t("reportList.confidenceLow")
+    return t("reportList.confidenceInsufficient")
+  }
+
+  const confidenceHint = (level: ConfidenceLevel): string => {
+    if (level === "high") return t("reportList.confidenceHighHint")
+    if (level === "medium") return t("reportList.confidenceMediumHint")
+    if (level === "low") return t("reportList.confidenceLowHint")
+    return t("reportList.confidenceInsufficient")
+  }
+
   const reportType = searchParams.get("reportType") ?? "all"
   const status = searchParams.get("status") ?? "all"
 
+  const typeLabel = (reportType: string): string => {
+    if (reportType === "individual") return t("type.individual")
+    if (reportType === "class") return t("type.class")
+    if (reportType === "grade") return t("type.grade")
+    return reportType
+  }
+
+  const statusLabel = (status: string): string => {
+    if (status === "draft") return t("status.draft")
+    if (status === "published") return t("status.published")
+    if (status === "archived") return t("status.archived")
+    return status
+  }
+
+  const studentTargetDisplay = (r: DiagnosticReportWithDetails): string => {
+    if (r.studentName) return r.studentName
+    if (r.reportType === "class") return t("reportList.classReportPlaceholder")
+    if (r.reportType === "grade") return t("reportList.gradeReportPlaceholder")
+    return "-"
+  }
+
+  // v3-P3-8: 当前分享的报告及链接
+  const sharedReport = shareId ? reports.find((r) => r.id === shareId) ?? null : null
+  const shareUrl = typeof window !== "undefined" && sharedReport
+    ? `${window.location.origin}/teacher/diagnostic/reports/${sharedReport.id}`
+    : ""
+
   return (
     <div className="space-y-4">
       {/* 过滤器 */}
       <div className="grid grid-cols-1 gap-4 rounded-lg border bg-card p-4 md:grid-cols-2">
         <div className="grid gap-2">
-          <Label className="text-xs">Report Type</Label>
+          <Label htmlFor="filter-report-type" className="text-xs">{t("filters.reportType")}</Label>
           <Select value={reportType} onValueChange={(v) => updateParam("reportType", v)}>
-            <SelectTrigger className="h-9">
-              <SelectValue placeholder="All types" />
+            <SelectTrigger id="filter-report-type" className="h-9">
+              <SelectValue placeholder={t("filters.allTypes")} />
             </SelectTrigger>
             <SelectContent>
-              <SelectItem value="all">All types</SelectItem>
-              <SelectItem value="individual">Individual</SelectItem>
-              <SelectItem value="class">Class</SelectItem>
-              <SelectItem value="grade">Grade</SelectItem>
+              <SelectItem value="all">{t("filters.allTypes")}</SelectItem>
+              <SelectItem value="individual">{t("type.individual")}</SelectItem>
+              <SelectItem value="class">{t("type.class")}</SelectItem>
+              <SelectItem value="grade">{t("type.grade")}</SelectItem>
             </SelectContent>
           </Select>
         </div>
         <div className="grid gap-2">
-          <Label className="text-xs">Status</Label>
+          <Label htmlFor="filter-report-status" className="text-xs">{t("filters.status")}</Label>
           <Select value={status} onValueChange={(v) => updateParam("status", v)}>
-            <SelectTrigger className="h-9">
-              <SelectValue placeholder="All statuses" />
+            <SelectTrigger id="filter-report-status" className="h-9">
+              <SelectValue placeholder={t("filters.allStatuses")} />
             </SelectTrigger>
             <SelectContent>
-              <SelectItem value="all">All statuses</SelectItem>
-              <SelectItem value="draft">Draft</SelectItem>
-              <SelectItem value="published">Published</SelectItem>
-              <SelectItem value="archived">Archived</SelectItem>
+              <SelectItem value="all">{t("filters.allStatuses")}</SelectItem>
+              <SelectItem value="draft">{t("status.draft")}</SelectItem>
+              <SelectItem value="published">{t("status.published")}</SelectItem>
+              <SelectItem value="archived">{t("status.archived")}</SelectItem>
             </SelectContent>
           </Select>
         </div>
@@ -149,71 +244,118 @@ export function ReportList({ reports }: ReportListProps) {
 
       {reports.length === 0 ? (
         <EmptyState
-          title="No diagnostic reports"
-          description="Generate diagnostic reports to see them here."
+          title={t("empty.noReports")}
+          description={t("reportList.noReportsDescription")}
           icon={FileText}
           className="border-none shadow-none"
         />
       ) : (
         <div className="rounded-md border bg-card">
           <Table>
-            <caption className="sr-only">学情诊断报告列表</caption>
+            <caption className="sr-only">{t("reportList.caption")}</caption>
             <TableHeader>
               <TableRow>
-                <TableHead>Type</TableHead>
-                <TableHead>Student / Target</TableHead>
-                <TableHead>Period</TableHead>
-                <TableHead className="text-right">Score</TableHead>
-                <TableHead>Status</TableHead>
-                <TableHead>Generated By</TableHead>
-                <TableHead>Date</TableHead>
-                {canManage ? <TableHead className="w-24">Actions</TableHead> : null}
+                <TableHead>{t("reportList.typeColumn")}</TableHead>
+                <TableHead>{t("reportList.studentTargetColumn")}</TableHead>
+                <TableHead>{t("reportList.periodColumn")}</TableHead>
+                <TableHead className="text-right">{t("reportList.scoreColumn")}</TableHead>
+                <TableHead>{t("reportList.confidenceColumn")}</TableHead>
+                <TableHead>{t("reportList.statusColumn")}</TableHead>
+                <TableHead>{t("reportList.generatedByColumn")}</TableHead>
+                <TableHead>{t("reportList.dateColumn")}</TableHead>
+                <TableHead className="w-40">{t("reportList.actionsColumn")}</TableHead>
               </TableRow>
             </TableHeader>
             <TableBody>
               {reports.map((r) => (
                 <TableRow key={r.id}>
                   <TableCell>
-                    <Badge variant="outline">{typeLabels[r.reportType] ?? r.reportType}</Badge>
+                    <Badge variant="outline">{typeLabel(r.reportType)}</Badge>
                   </TableCell>
-                  <TableCell className="font-medium">{r.studentName ?? (r.reportType === "class" ? "（班级报告）" : r.reportType === "grade" ? "（年级报告）" : "-")}</TableCell>
+                  <TableCell className="font-medium">{studentTargetDisplay(r)}</TableCell>
                   <TableCell>{r.period ?? "-"}</TableCell>
                   <TableCell className="text-right font-mono">
                     {r.overallScore !== null ? `${r.overallScore.toFixed(1)}%` : "-"}
                   </TableCell>
                   <TableCell>
-                    <Badge variant={statusColors[r.status] ?? "secondary"}>{r.status}</Badge>
+                    {(() => {
+                      const level = getConfidenceLevel(r)
+                      return (
+                        <Tooltip>
+                          <TooltipTrigger asChild>
+                            <Badge
+                              variant={confidenceBadgeVariant[level]}
+                              aria-label={t("reportList.confidenceAriaLabel", { level: confidenceLabel(level) })}
+                            >
+                              {confidenceLabel(level)}
+                            </Badge>
+                          </TooltipTrigger>
+                          <TooltipContent>{confidenceHint(level)}</TooltipContent>
+                        </Tooltip>
+                      )
+                    })()}
+                  </TableCell>
+                  <TableCell>
+                    <Badge variant={statusColors[r.status] ?? "secondary"}>{statusLabel(r.status)}</Badge>
                   </TableCell>
                   <TableCell className="text-muted-foreground">{r.generatedByName ?? "-"}</TableCell>
                   <TableCell className="text-muted-foreground">{formatDate(r.createdAt)}</TableCell>
-                  {canManage ? (
-                    <TableCell>
-                      <div className="flex gap-1">
-                        {r.status === "draft" ? (
-                          <Button
-                            variant="ghost"
-                            size="icon"
-                            className="h-8 w-8 text-green-600"
-                            onClick={() => setPublishId(r.id)}
-                            title="Publish"
-                            aria-label={`发布报告 ${r.studentName}`}
-                          >
-                            <Send className="h-4 w-4" />
-                          </Button>
-                        ) : null}
+                  <TableCell>
+                    <div className="flex gap-1">
+                      {/* v3-P2-4: 导出按钮（所有角色可见，受 exportDiagnosticReportAction 权限校验保护） */}
+                      <Button
+                        variant="ghost"
+                        size="icon"
+                        className="h-8 w-8"
+                        onClick={() => handleExport(r.id)}
+                        disabled={isBusy}
+                        title={t("report.export")}
+                        aria-label={t("reportList.exportAriaLabel", { studentName: r.studentName ?? "" })}
+                      >
+                        <Download className="h-4 w-4" />
+                      </Button>
+                      {/* v3-P3-8: 分享按钮（仅教师可见） */}
+                      {canManage ? (
+                        <Button
+                          variant="ghost"
+                          size="icon"
+                          className="h-8 w-8"
+                          onClick={() => setShareId(r.id)}
+                          disabled={isBusy}
+                          title={t("reportList.share")}
+                          aria-label={t("reportList.shareAriaLabel", { studentName: r.studentName ?? "" })}
+                        >
+                          <Share2 className="h-4 w-4" />
+                        </Button>
+                      ) : null}
+                      {canManage && r.status === "draft" ? (
+                        <Button
+                          variant="ghost"
+                          size="icon"
+                          className="h-8 w-8 text-green-600"
+                          onClick={() => setPublishId(r.id)}
+                          disabled={isBusy}
+                          title={t("report.publish")}
+                          aria-label={t("reportList.publishAriaLabel", { studentName: r.studentName ?? "" })}
+                        >
+                          <Send className="h-4 w-4" />
+                        </Button>
+                      ) : null}
+                      {canManage ? (
                         <Button
                           variant="ghost"
                           size="icon"
                           className="h-8 w-8 text-destructive"
                           onClick={() => setDeleteId(r.id)}
-                          title="Delete"
-                          aria-label={`删除报告 ${r.studentName}`}
+                          disabled={isBusy}
+                          title={t("report.delete")}
+                          aria-label={t("reportList.deleteAriaLabel", { studentName: r.studentName ?? "" })}
                         >
                           <Trash2 className="h-4 w-4" />
                         </Button>
-                      </div>
-                    </TableCell>
-                  ) : null}
+                      ) : null}
+                    </div>
+                  </TableCell>
                 </TableRow>
               ))}
             </TableBody>
@@ -225,17 +367,17 @@ export function ReportList({ reports }: ReportListProps) {
       <Dialog open={publishId !== null} onOpenChange={(open) => !open && setPublishId(null)}>
         <DialogContent>
           <DialogHeader>
-            <DialogTitle>Publish Report</DialogTitle>
+            <DialogTitle>{t("report.publishTitle")}</DialogTitle>
             <DialogDescription>
-              Once published, the report will be visible to students. Continue?
+              {t("reportList.publishConfirmation")}
             </DialogDescription>
           </DialogHeader>
           <DialogFooter>
             <Button variant="outline" onClick={() => setPublishId(null)} disabled={isBusy}>
-              Cancel
+              {t("report.cancel")}
             </Button>
             <Button onClick={handlePublish} disabled={isBusy}>
-              {isBusy ? "Publishing..." : "Publish"}
+              {isBusy ? t("report.publishing") : t("report.publish")}
             </Button>
           </DialogFooter>
         </DialogContent>
@@ -245,17 +387,55 @@ export function ReportList({ reports }: ReportListProps) {
       <Dialog open={deleteId !== null} onOpenChange={(open) => !open && setDeleteId(null)}>
         <DialogContent>
           <DialogHeader>
-            <DialogTitle>Delete Report</DialogTitle>
+            <DialogTitle>{t("report.deleteTitle")}</DialogTitle>
             <DialogDescription>
-              Are you sure you want to delete this diagnostic report? This action cannot be undone.
+              {t("report.deleteConfirmation")}
             </DialogDescription>
           </DialogHeader>
           <DialogFooter>
             <Button variant="outline" onClick={() => setDeleteId(null)} disabled={isBusy}>
-              Cancel
+              {t("report.cancel")}
             </Button>
             <Button variant="destructive" onClick={handleDelete} disabled={isBusy}>
-              {isBusy ? "Deleting..." : "Delete"}
+              {isBusy ? t("report.deleting") : t("report.delete")}
+            </Button>
+          </DialogFooter>
+        </DialogContent>
+      </Dialog>
+
+      {/* v3-P3-8: 分享报告 */}
+      <Dialog open={shareId !== null} onOpenChange={(open) => !open && setShareId(null)}>
+        <DialogContent>
+          <DialogHeader>
+            <DialogTitle>{t("reportList.shareTitle")}</DialogTitle>
+            <DialogDescription>{t("reportList.shareDescription")}</DialogDescription>
+          </DialogHeader>
+          <div className="space-y-4">
+            {sharedReport?.summary ? (
+              <div className="rounded-md border bg-muted/50 p-3">
+                <p className="text-sm">{sharedReport.summary}</p>
+              </div>
+            ) : null}
+            <div className="space-y-2">
+              <Label htmlFor="share-link" className="text-xs">{t("reportList.shareLinkLabel")}</Label>
+              <div className="flex gap-2">
+                <Input
+                  id="share-link"
+                  readOnly
+                  value={shareUrl}
+                  aria-label={t("reportList.shareLinkAriaLabel")}
+                  className="text-sm"
+                />
+                <Button onClick={handleCopyLink} className="shrink-0">
+                  <Copy className="mr-1 h-4 w-4" />
+                  {t("reportList.copyLink")}
+                </Button>
+              </div>
+            </div>
+          </div>
+          <DialogFooter>
+            <Button variant="outline" onClick={() => setShareId(null)}>
+              {t("report.cancel")}
             </Button>
           </DialogFooter>
         </DialogContent>

src/modules/diagnostic/components/student-diagnostic-view.tsx

@@ -1,28 +1,50 @@
 "use client"
 
 import Link from "next/link"
+import { useTranslations } from "next-intl"
 import { Award, AlertTriangle, Lightbulb, FileText, History, ArrowRight } from "lucide-react"
 
 import { Card, CardContent, CardHeader, CardTitle, CardDescription } from "@/shared/components/ui/card"
 import { Badge } from "@/shared/components/ui/badge"
 import { Button } from "@/shared/components/ui/button"
+import { Tooltip, TooltipContent, TooltipTrigger } from "@/shared/components/ui/tooltip"
 import { EmptyState } from "@/shared/components/ui/empty-state"
 import { formatDate } from "@/shared/lib/utils"
 import { MasteryRadarChart } from "./mastery-radar-chart"
+import {
+  getConfidenceLevel,
+  confidenceBadgeVariant,
+  type ConfidenceLevel,
+} from "./confidence-utils"
 import type { DiagnosticReportWithDetails, MasteryRadarPoint, StudentMasterySummary } from "../types"
 
 interface StudentDiagnosticViewProps {
   summary: StudentMasterySummary | null
   reports: DiagnosticReportWithDetails[]
   classAverageMastery?: MasteryRadarPoint[]
+  /**
+   * v3-P2-6: "练习"按钮的跳转基础路径。
+   * - 学生视角：默认 `/student/learning/assignments`
+   * - 教师视角：传入 `/teacher/questions`（题目库支持 kp 查询参数筛选）
+   * - 家长视角：传入 `null` 隐藏练习按钮（家长无练习入口）
+   * 最终链接会附加 `?kp={knowledgePointId}` 实现个性化练习推荐。
+   */
+  practiceHrefBase?: string | null
 }
 
-export function StudentDiagnosticView({ summary, reports, classAverageMastery }: StudentDiagnosticViewProps) {
+export function StudentDiagnosticView({
+  summary,
+  reports,
+  classAverageMastery,
+  practiceHrefBase = "/student/learning/assignments",
+}: StudentDiagnosticViewProps) {
+  const t = useTranslations("diagnostic")
+
   if (!summary) {
     return (
       <EmptyState
-        title="No diagnostic data"
-        description="Unable to load student mastery data."
+        title={t("empty.noData")}
+        description={t("studentDiagnostic.noDataDescription")}
         icon={FileText}
         className="border-none shadow-none"
       />
@@ -39,7 +61,38 @@ export function StudentDiagnosticView({ summary, reports, classAverageMastery }:
   })
 
   const publishedReports = reports.filter((r) => r.status === "published")
-  const latestReport = publishedReports[0] ?? reports[0] ?? null
+  // v4-P1-3: 移除草稿回退逻辑，仅展示已发布报告
+  // 调用方（学生/家长页面）已传 status: "published" 过滤，此处双重保障
+  const latestReport = publishedReports[0] ?? null
+
+  const statusLabel = (status: string): string => {
+    if (status === "draft") return t("status.draft")
+    if (status === "published") return t("status.published")
+    if (status === "archived") return t("status.archived")
+    return status
+  }
+
+  const typeLabel = (reportType: string): string => {
+    if (reportType === "individual") return t("type.individual")
+    if (reportType === "class") return t("type.class")
+    if (reportType === "grade") return t("type.grade")
+    return reportType
+  }
+
+  // v4-P3-7: 置信度标签与提示
+  const confidenceLabel = (level: ConfidenceLevel): string => {
+    if (level === "high") return t("reportList.confidenceHigh")
+    if (level === "medium") return t("reportList.confidenceMedium")
+    if (level === "low") return t("reportList.confidenceLow")
+    return t("reportList.confidenceInsufficient")
+  }
+
+  const confidenceHint = (level: ConfidenceLevel): string => {
+    if (level === "high") return t("reportList.confidenceHighHint")
+    if (level === "medium") return t("reportList.confidenceMediumHint")
+    if (level === "low") return t("reportList.confidenceLowHint")
+    return t("reportList.confidenceInsufficient")
+  }
 
   return (
     <div className="space-y-6">
@@ -47,7 +100,7 @@ export function StudentDiagnosticView({ summary, reports, classAverageMastery }:
       <div className="grid grid-cols-1 gap-4 md:grid-cols-4">
         <Card>
           <CardHeader className="pb-2">
-            <CardTitle className="text-sm font-medium text-muted-foreground">Student</CardTitle>
+            <CardTitle className="text-sm font-medium text-muted-foreground">{t("summary.student")}</CardTitle>
           </CardHeader>
           <CardContent>
             <p className="text-2xl font-bold">{summary.studentName}</p>
@@ -55,7 +108,7 @@ export function StudentDiagnosticView({ summary, reports, classAverageMastery }:
         </Card>
         <Card>
           <CardHeader className="pb-2">
-            <CardTitle className="text-sm font-medium text-muted-foreground">Overall Mastery</CardTitle>
+            <CardTitle className="text-sm font-medium text-muted-foreground">{t("summary.overallMastery")}</CardTitle>
           </CardHeader>
           <CardContent>
             <p className="text-2xl font-bold">{summary.averageMastery.toFixed(1)}%</p>
@@ -63,7 +116,7 @@ export function StudentDiagnosticView({ summary, reports, classAverageMastery }:
         </Card>
         <Card>
           <CardHeader className="pb-2">
-            <CardTitle className="text-sm font-medium text-muted-foreground">Strengths</CardTitle>
+            <CardTitle className="text-sm font-medium text-muted-foreground">{t("summary.strengths")}</CardTitle>
           </CardHeader>
           <CardContent>
             <p className="text-2xl font-bold text-green-600">{summary.strengths.length}</p>
@@ -71,7 +124,7 @@ export function StudentDiagnosticView({ summary, reports, classAverageMastery }:
         </Card>
         <Card>
           <CardHeader className="pb-2">
-            <CardTitle className="text-sm font-medium text-muted-foreground">Weaknesses</CardTitle>
+            <CardTitle className="text-sm font-medium text-muted-foreground">{t("summary.weaknesses")}</CardTitle>
           </CardHeader>
           <CardContent>
             <p className="text-2xl font-bold text-red-600">{summary.weaknesses.length}</p>
@@ -88,15 +141,15 @@ export function StudentDiagnosticView({ summary, reports, classAverageMastery }:
           <CardHeader>
             <CardTitle className="flex items-center gap-2">
               <Award className="h-4 w-4 text-green-600" />
-              Strengths (≥80%)
+              {t("strengths.title")}
             </CardTitle>
-            <CardDescription>Knowledge points with high mastery.</CardDescription>
+            <CardDescription>{t("studentDiagnostic.strengthsDescription")}</CardDescription>
           </CardHeader>
           <CardContent>
             {summary.strengths.length === 0 ? (
-              <p className="text-sm text-muted-foreground">No strengths identified yet.</p>
+              <p className="text-sm text-muted-foreground">{t("studentDiagnostic.noStrengths")}</p>
             ) : (
-              <ul className="space-y-2" role="list" aria-label="优势知识点列表">
+              <ul className="space-y-2" role="list" aria-label={t("studentDiagnostic.strengthsListAriaLabel")}>
                 {summary.strengths.map((m) => (
                   <li key={m.knowledgePointId} className="flex items-center justify-between">
                     <span className="text-sm">{m.knowledgePointName}</span>
@@ -111,27 +164,29 @@ export function StudentDiagnosticView({ summary, reports, classAverageMastery }:
           <CardHeader>
             <CardTitle className="flex items-center gap-2">
               <AlertTriangle className="h-4 w-4 text-red-600" />
-              Weaknesses (&lt;60%)
+              {t("weaknesses.title")}
             </CardTitle>
-            <CardDescription>Knowledge points needing attention.</CardDescription>
+            <CardDescription>{t("studentDiagnostic.weaknessesDescription")}</CardDescription>
           </CardHeader>
           <CardContent>
             {summary.weaknesses.length === 0 ? (
-              <p className="text-sm text-muted-foreground">No weaknesses identified.</p>
+              <p className="text-sm text-muted-foreground">{t("studentDiagnostic.noWeaknesses")}</p>
             ) : (
-              <ul className="space-y-2" role="list" aria-label="薄弱知识点列表">
+              <ul className="space-y-2" role="list" aria-label={t("studentDiagnostic.weaknessesListAriaLabel")}>
                 {summary.weaknesses.map((m) => (
                   <li key={m.knowledgePointId} className="flex items-center justify-between gap-2">
                     <div className="flex items-center gap-2 min-w-0">
                       <span className="text-sm truncate">{m.knowledgePointName}</span>
                       <Badge variant="destructive" className="shrink-0">{m.masteryLevel.toFixed(1)}%</Badge>
                     </div>
-                    <Button asChild variant="ghost" size="sm" className="h-7 shrink-0 text-xs">
-                      <Link href="/student/learning/assignments">
-                        Practice
-                        <ArrowRight className="ml-1 h-3 w-3" />
-                      </Link>
-                    </Button>
+                    {practiceHrefBase ? (
+                      <Button asChild variant="ghost" size="sm" className="h-7 shrink-0 text-xs" aria-label={t("studentDiagnostic.practiceAriaLabel", { name: m.knowledgePointName })}>
+                        <Link href={`${practiceHrefBase}?kp=${m.knowledgePointId}`}>
+                          {t("weaknesses.practice")}
+                          <ArrowRight className="ml-1 h-3 w-3" />
+                        </Link>
+                      </Button>
+                    ) : null}
                   </li>
                 ))}
               </ul>
@@ -146,13 +201,32 @@ export function StudentDiagnosticView({ summary, reports, classAverageMastery }:
           <CardHeader>
             <CardTitle className="flex items-center gap-2">
               <Lightbulb className="h-4 w-4" />
-              Diagnostic Report
+              {t("studentDiagnostic.diagnosticReportTitle")}
               <Badge variant={latestReport.status === "published" ? "default" : "secondary"}>
-                {latestReport.status}
+                {statusLabel(latestReport.status)}
               </Badge>
+              {(() => {
+                const level = getConfidenceLevel(latestReport)
+                return (
+                  <Tooltip>
+                    <TooltipTrigger asChild>
+                      <Badge
+                        variant={confidenceBadgeVariant[level]}
+                        aria-label={t("reportList.confidenceAriaLabel", { level: confidenceLabel(level) })}
+                      >
+                        {confidenceLabel(level)}
+                      </Badge>
+                    </TooltipTrigger>
+                    <TooltipContent>{confidenceHint(level)}</TooltipContent>
+                  </Tooltip>
+                )
+              })()}
             </CardTitle>
             <CardDescription>
-              Period: {latestReport.period ?? "-"} · Overall: {latestReport.overallScore?.toFixed(1) ?? "-"}%
+              {t("studentDiagnostic.reportMeta", {
+                period: latestReport.period ?? "-",
+                score: latestReport.overallScore?.toFixed(1) ?? "-",
+              })}
             </CardDescription>
           </CardHeader>
           <CardContent className="space-y-4">
@@ -161,10 +235,10 @@ export function StudentDiagnosticView({ summary, reports, classAverageMastery }:
             ) : null}
             {latestReport.recommendations && latestReport.recommendations.length > 0 ? (
               <div>
-                <h4 className="mb-2 text-sm font-semibold">Recommendations</h4>
-                <ul className="space-y-1.5" role="list" aria-label="学习建议列表">
+                <h4 className="mb-2 text-sm font-semibold">{t("report.recommendations")}</h4>
+                <ul className="space-y-1.5" role="list" aria-label={t("studentDiagnostic.recommendationsListAriaLabel")}>
                   {latestReport.recommendations.map((rec, i) => (
-                    <li key={i} className="text-sm text-muted-foreground">• {rec}</li>
+                    <li key={rec || `rec-${i}`} className="text-sm text-muted-foreground">• {rec}</li>
                   ))}
                 </ul>
               </div>
@@ -179,9 +253,9 @@ export function StudentDiagnosticView({ summary, reports, classAverageMastery }:
           <CardHeader>
             <CardTitle className="flex items-center gap-2">
               <History className="h-4 w-4" />
-              Report History
+              {t("report.history")}
             </CardTitle>
-            <CardDescription>Past diagnostic reports (newest first).</CardDescription>
+            <CardDescription>{t("studentDiagnostic.historyDescription")}</CardDescription>
           </CardHeader>
           <CardContent>
             <div className="space-y-2">
@@ -193,15 +267,19 @@ export function StudentDiagnosticView({ summary, reports, classAverageMastery }:
                   <div className="min-w-0 space-y-1">
                     <div className="flex items-center gap-2">
                       <span className="text-sm font-medium">
-                        {r.period ?? "Untitled period"}
+                        {r.period ?? t("studentDiagnostic.untitledPeriod")}
                       </span>
                       <Badge variant="outline" className="text-xs">
-                        {r.reportType}
+                        {typeLabel(r.reportType)}
                       </Badge>
                     </div>
                     <p className="text-xs text-muted-foreground">
-                      {formatDate(r.createdAt)}
-                      {r.overallScore !== null ? ` · Overall: ${r.overallScore.toFixed(1)}%` : ""}
+                      {r.overallScore !== null
+                        ? t("studentDiagnostic.historyReportMeta", {
+                            date: formatDate(r.createdAt),
+                            score: r.overallScore.toFixed(1),
+                          })
+                        : formatDate(r.createdAt)}
                     </p>
                   </div>
                 </div>