feat: Mentees & Activity tab on /admin/mentors

Adds a project-centric ops view for mentor management:
- New mentor.getMenteeActivity tRPC procedure aggregates every project
  with wantsMentorship=true and derives a status (unassigned / assigned
  / active / stalled) from the latest message + file activity.
- /admin/mentors becomes a tabbed page: existing Mentor list +
  new Mentees & Activity table with status pills, search, and a
  per-row Assign/Open CTA linking to /admin/projects/[id]/mentor.
- Includes 2 unit tests covering classification + program scoping.

Also: ignore .remember/ (plugin scratch dir).

.gitignore

@@ -62,3 +62,4 @@ build-output.txt
 # Private keys and secrets
 private/
 public/build-id.json
+.remember/

src/app/(admin)/admin/mentors/page.tsx

@@ -13,6 +13,7 @@ import { Input } from '@/components/ui/input'
 import { Badge } from '@/components/ui/badge'
 import { Button } from '@/components/ui/button'
 import { Skeleton } from '@/components/ui/skeleton'
+import { Tabs, TabsContent, TabsList, TabsTrigger } from '@/components/ui/tabs'
 import {
   Table,
   TableBody,
@@ -21,7 +22,8 @@ import {
   TableHeader,
   TableRow,
 } from '@/components/ui/table'
-import { ArrowUpDown, Search, Users } from 'lucide-react'
+import { ArrowUpDown, GraduationCap, Search, Users } from 'lucide-react'
+import { formatEnumLabel } from '@/lib/utils'
 
 type SortKey = 'name' | 'load' | 'capacity' | 'lastActivity'
 
@@ -37,6 +39,16 @@ function formatRelativePast(date: Date | string | null): string {
   return `${Math.max(0, minutes)}m ago`
 }
 
+const STATUS_BADGE: Record<
+  'unassigned' | 'assigned' | 'active' | 'stalled',
+  { label: string; variant: 'default' | 'secondary' | 'destructive' | 'outline' }
+> = {
+  unassigned: { label: 'Unassigned', variant: 'outline' },
+  assigned: { label: 'Assigned', variant: 'secondary' },
+  active: { label: 'Active', variant: 'default' },
+  stalled: { label: 'Stalled', variant: 'destructive' },
+}
+
 type Mentor = {
   id: string
   name: string | null
@@ -50,7 +62,7 @@ type Mentor = {
   lastActivityAt: Date | string | null
 }
 
-export default function MentorsListPage() {
+function MentorListPanel() {
   const [search, setSearch] = useState('')
   const [sortKey, setSortKey] = useState<SortKey>('load')
   const [sortDir, setSortDir] = useState<'asc' | 'desc'>('asc')
@@ -128,21 +140,6 @@ export default function MentorsListPage() {
 
   return (
     <div className="space-y-6">
-      <div className="flex items-center justify-between">
-        <div>
-          <h1 className="text-2xl font-semibold tracking-tight">Mentors</h1>
-          <p className="text-muted-foreground">
-            All users with the MENTOR role and their current workload.
-          </p>
-        </div>
-        <Button asChild variant="outline">
-          <Link href="/admin/members">
-            <Users className="mr-2 h-4 w-4" />
-            Manage Members
-          </Link>
-        </Button>
-      </div>
-
       <div className="grid gap-4 md:grid-cols-3">
         <Card>
           <CardHeader className="pb-2">
@@ -279,3 +276,252 @@ export default function MentorsListPage() {
     </div>
   )
 }
+
+type StatusFilter = 'all' | 'unassigned' | 'assigned' | 'active' | 'stalled'
+
+function MenteeActivityPanel() {
+  const [search, setSearch] = useState('')
+  const [statusFilter, setStatusFilter] = useState<StatusFilter>('all')
+
+  const { data, isLoading } = trpc.mentor.getMenteeActivity.useQuery({})
+
+  const filtered = useMemo(() => {
+    if (!data) return []
+    const q = search.trim().toLowerCase()
+    return data.rows.filter((r) => {
+      if (statusFilter !== 'all' && r.status !== statusFilter) return false
+      if (!q) return true
+      const hay = [
+        r.project.title,
+        r.project.country ?? '',
+        r.teamLead?.name ?? '',
+        r.teamLead?.email ?? '',
+        r.mentor?.name ?? '',
+        r.mentor?.email ?? '',
+      ]
+        .join(' ')
+        .toLowerCase()
+      return hay.includes(q)
+    })
+  }, [data, search, statusFilter])
+
+  const totals = data?.totals ?? { unassigned: 0, assigned: 0, active: 0, stalled: 0 }
+
+  const StatusPill = ({ value, label, count }: { value: StatusFilter; label: string; count: number }) => (
+    <button
+      type="button"
+      onClick={() => setStatusFilter(value)}
+      className={`rounded-md border px-2.5 py-1 text-xs font-medium transition-colors ${
+        statusFilter === value
+          ? 'bg-primary text-primary-foreground border-primary'
+          : 'bg-background hover:bg-muted'
+      }`}
+    >
+      {label} <span className="tabular-nums opacity-80">({count})</span>
+    </button>
+  )
+
+  return (
+    <div className="space-y-6">
+      <div className="grid gap-4 md:grid-cols-4">
+        <Card>
+          <CardHeader className="pb-2">
+            <CardTitle className="text-muted-foreground text-xs font-medium uppercase tracking-wide">
+              Unassigned
+            </CardTitle>
+          </CardHeader>
+          <CardContent>
+            <div className="text-3xl font-bold tabular-nums">{totals.unassigned}</div>
+          </CardContent>
+        </Card>
+        <Card>
+          <CardHeader className="pb-2">
+            <CardTitle className="text-muted-foreground text-xs font-medium uppercase tracking-wide">
+              Assigned
+            </CardTitle>
+          </CardHeader>
+          <CardContent>
+            <div className="text-3xl font-bold tabular-nums">{totals.assigned}</div>
+          </CardContent>
+        </Card>
+        <Card>
+          <CardHeader className="pb-2">
+            <CardTitle className="text-muted-foreground text-xs font-medium uppercase tracking-wide">
+              Active
+            </CardTitle>
+          </CardHeader>
+          <CardContent>
+            <div className="text-3xl font-bold tabular-nums">{totals.active}</div>
+          </CardContent>
+        </Card>
+        <Card>
+          <CardHeader className="pb-2">
+            <CardTitle className="text-muted-foreground text-xs font-medium uppercase tracking-wide">
+              Stalled
+            </CardTitle>
+          </CardHeader>
+          <CardContent>
+            <div className="text-3xl font-bold tabular-nums text-destructive">
+              {totals.stalled}
+            </div>
+          </CardContent>
+        </Card>
+      </div>
+
+      <Card>
+        <CardHeader className="space-y-4">
+          <div className="flex items-center justify-between gap-4">
+            <CardTitle className="text-base">Mentee teams</CardTitle>
+            <div className="flex flex-wrap gap-1.5">
+              <StatusPill
+                value="all"
+                label="All"
+                count={
+                  totals.unassigned + totals.assigned + totals.active + totals.stalled
+                }
+              />
+              <StatusPill value="unassigned" label="Unassigned" count={totals.unassigned} />
+              <StatusPill value="assigned" label="Assigned" count={totals.assigned} />
+              <StatusPill value="active" label="Active" count={totals.active} />
+              <StatusPill value="stalled" label="Stalled" count={totals.stalled} />
+            </div>
+          </div>
+          <div className="relative">
+            <Search className="text-muted-foreground absolute left-3 top-1/2 h-4 w-4 -translate-y-1/2" />
+            <Input
+              value={search}
+              onChange={(e) => setSearch(e.target.value)}
+              placeholder="Search by project, team lead, or mentor…"
+              className="pl-9"
+            />
+          </div>
+        </CardHeader>
+        <CardContent>
+          {isLoading ? (
+            <div className="space-y-2">
+              {[1, 2, 3, 4, 5].map((i) => (
+                <Skeleton key={i} className="h-14 w-full" />
+              ))}
+            </div>
+          ) : filtered.length === 0 ? (
+            <div className="text-muted-foreground py-12 text-center text-sm">
+              {search || statusFilter !== 'all'
+                ? 'No matching teams.'
+                : 'No teams have requested mentorship yet.'}
+            </div>
+          ) : (
+            <div className="overflow-hidden rounded-md border">
+              <Table>
+                <TableHeader>
+                  <TableRow>
+                    <TableHead>Project</TableHead>
+                    <TableHead>Status</TableHead>
+                    <TableHead>Mentor</TableHead>
+                    <TableHead className="text-right">Messages</TableHead>
+                    <TableHead className="text-right">Files</TableHead>
+                    <TableHead>Last activity</TableHead>
+                    <TableHead></TableHead>
+                  </TableRow>
+                </TableHeader>
+                <TableBody>
+                  {filtered.map((r) => {
+                    const badge = STATUS_BADGE[r.status]
+                    return (
+                      <TableRow key={r.project.id}>
+                        <TableCell>
+                          <div className="font-medium">{r.project.title}</div>
+                          <div className="text-muted-foreground text-xs">
+                            {r.teamLead?.name ?? r.teamLead?.email ?? '—'}
+                            {r.project.oceanIssue && (
+                              <>
+                                {' · '}
+                                {formatEnumLabel(r.project.oceanIssue)}
+                              </>
+                            )}
+                          </div>
+                        </TableCell>
+                        <TableCell>
+                          <Badge variant={badge.variant} className="text-xs">
+                            {badge.label}
+                          </Badge>
+                        </TableCell>
+                        <TableCell>
+                          {r.mentor ? (
+                            <div className="text-sm">
+                              <div>{r.mentor.name ?? r.mentor.email}</div>
+                              <div className="text-muted-foreground text-xs tabular-nums">
+                                {r.mentor.currentLoad}
+                                {r.mentor.maxAssignments != null
+                                  ? `/${r.mentor.maxAssignments}`
+                                  : ''}
+                                {' load'}
+                              </div>
+                            </div>
+                          ) : (
+                            <span className="text-muted-foreground text-sm">—</span>
+                          )}
+                        </TableCell>
+                        <TableCell className="text-right tabular-nums">
+                          {r.messageCount}
+                        </TableCell>
+                        <TableCell className="text-right tabular-nums">{r.fileCount}</TableCell>
+                        <TableCell className="text-sm">
+                          {formatRelativePast(r.lastActivityAt as unknown as Date | null)}
+                        </TableCell>
+                        <TableCell className="text-right">
+                          <Button asChild size="sm" variant="outline">
+                            <Link href={`/admin/projects/${r.project.id}/mentor`}>
+                              {r.mentor ? 'Open' : 'Assign'}
+                            </Link>
+                          </Button>
+                        </TableCell>
+                      </TableRow>
+                    )
+                  })}
+                </TableBody>
+              </Table>
+            </div>
+          )}
+        </CardContent>
+      </Card>
+    </div>
+  )
+}
+
+export default function MentorsListPage() {
+  return (
+    <div className="space-y-6">
+      <div className="flex items-center justify-between">
+        <div>
+          <h1 className="text-2xl font-semibold tracking-tight">Mentors</h1>
+          <p className="text-muted-foreground">
+            Manage the mentor pool and track mentee teams across the program.
+          </p>
+        </div>
+        <Button asChild variant="outline">
+          <Link href="/admin/members">
+            <Users className="mr-2 h-4 w-4" />
+            Manage Members
+          </Link>
+        </Button>
+      </div>
+
+      <Tabs defaultValue="mentors" className="space-y-6">
+        <TabsList>
+          <TabsTrigger value="mentors">
+            <GraduationCap className="mr-2 h-4 w-4" /> Mentors
+          </TabsTrigger>
+          <TabsTrigger value="mentees">
+            <Users className="mr-2 h-4 w-4" /> Mentees & Activity
+          </TabsTrigger>
+        </TabsList>
+        <TabsContent value="mentors">
+          <MentorListPanel />
+        </TabsContent>
+        <TabsContent value="mentees">
+          <MenteeActivityPanel />
+        </TabsContent>
+      </Tabs>
+    </div>
+  )
+}

src/server/routers/mentor.ts

@@ -1072,6 +1072,125 @@ export const mentorRouter = router({
       }
     }),
 
+  /**
+   * Project-centric activity view: every project that wants mentorship,
+   * with assignment status, latest activity timestamps, and a derived
+   * status (unassigned / assigned / active / stalled).
+   * Drives the "Mentees & Activity" tab on /admin/mentors.
+   */
+  getMenteeActivity: adminProcedure
+    .input(z.object({ programId: z.string().optional() }))
+    .query(async ({ ctx, input }) => {
+      const projects = await ctx.prisma.project.findMany({
+        where: {
+          wantsMentorship: true,
+          ...(input.programId ? { programId: input.programId } : {}),
+        },
+        select: {
+          id: true,
+          title: true,
+          country: true,
+          status: true,
+          oceanIssue: true,
+          competitionCategory: true,
+          mentorAssignment: {
+            select: {
+              id: true,
+              method: true,
+              assignedAt: true,
+              completionStatus: true,
+              mentor: {
+                select: {
+                  id: true,
+                  name: true,
+                  email: true,
+                  maxAssignments: true,
+                  _count: { select: { mentorAssignments: true } },
+                },
+              },
+              messages: {
+                orderBy: { createdAt: 'desc' },
+                take: 1,
+                select: { createdAt: true },
+              },
+              files: {
+                orderBy: { createdAt: 'desc' },
+                take: 1,
+                select: { createdAt: true },
+              },
+              _count: { select: { messages: true, files: true } },
+            },
+          },
+          teamMembers: {
+            where: { role: 'LEAD' },
+            take: 1,
+            select: { user: { select: { name: true, email: true } } },
+          },
+        },
+        orderBy: { title: 'asc' },
+      })
+
+      const ACTIVE_WINDOW_MS = 7 * 86_400_000
+      const STALLED_WINDOW_MS = 14 * 86_400_000
+      const now = Date.now()
+
+      const totals = { unassigned: 0, assigned: 0, active: 0, stalled: 0 }
+
+      const rows = projects.map((p) => {
+        const ma = p.mentorAssignment
+        const lastMessageAt = ma?.messages[0]?.createdAt ?? null
+        const lastFileAt = ma?.files[0]?.createdAt ?? null
+        const lastActivityAt = [lastMessageAt, lastFileAt]
+          .filter((d): d is Date => d != null)
+          .sort((a, b) => b.getTime() - a.getTime())[0] ?? null
+
+        let status: 'unassigned' | 'assigned' | 'active' | 'stalled'
+        if (!ma) {
+          status = 'unassigned'
+        } else if (lastActivityAt && now - lastActivityAt.getTime() <= ACTIVE_WINDOW_MS) {
+          status = 'active'
+        } else {
+          const referenceTime = lastActivityAt ?? ma.assignedAt
+          const elapsed = now - referenceTime.getTime()
+          status = elapsed > STALLED_WINDOW_MS ? 'stalled' : 'assigned'
+        }
+        totals[status]++
+
+        const teamLead = p.teamMembers[0]?.user ?? null
+
+        return {
+          project: {
+            id: p.id,
+            title: p.title,
+            country: p.country,
+            status: p.status,
+            oceanIssue: p.oceanIssue,
+            competitionCategory: p.competitionCategory,
+          },
+          teamLead: teamLead ? { name: teamLead.name, email: teamLead.email } : null,
+          mentor: ma?.mentor
+            ? {
+                id: ma.mentor.id,
+                name: ma.mentor.name,
+                email: ma.mentor.email,
+                currentLoad: ma.mentor._count.mentorAssignments,
+                maxAssignments: ma.mentor.maxAssignments,
+              }
+            : null,
+          assignmentMethod: ma?.method ?? null,
+          assignedAt: ma?.assignedAt ?? null,
+          lastMessageAt,
+          lastFileAt,
+          lastActivityAt,
+          messageCount: ma?._count.messages ?? 0,
+          fileCount: ma?._count.files ?? 0,
+          status,
+        }
+      })
+
+      return { rows, totals }
+    }),
+
   /**
    * Get mentor's assigned projects
    */

tests/unit/mentee-activity.test.ts

@@ -0,0 +1,167 @@
+import { afterAll, describe, expect, it } from 'vitest'
+import { prisma, createCaller } from '../setup'
+import {
+  createTestUser,
+  createTestProgram,
+  createTestProject,
+  cleanupTestData,
+  uid,
+} from '../helpers'
+import { mentorRouter } from '../../src/server/routers/mentor'
+import type { UserRole } from '@prisma/client'
+
+async function createUserWithRoles(primaryRole: UserRole, rolesArray: UserRole[]) {
+  const id = uid('user')
+  return prisma.user.create({
+    data: {
+      id,
+      email: `${id}@test.local`,
+      name: `Test ${primaryRole}`,
+      role: primaryRole,
+      roles: rolesArray,
+      status: 'ACTIVE',
+    },
+  })
+}
+
+const DAY = 86_400_000
+
+describe('mentor.getMenteeActivity', () => {
+  const programIds: string[] = []
+  const userIds: string[] = []
+
+  afterAll(async () => {
+    for (const programId of programIds) {
+      await prisma.mentorAssignment.deleteMany({ where: { project: { programId } } })
+      await cleanupTestData(programId, [])
+    }
+    if (userIds.length > 0) {
+      await prisma.user.deleteMany({ where: { id: { in: userIds } } })
+    }
+  })
+
+  it('classifies projects as unassigned / assigned / active / stalled and returns totals', async () => {
+    const admin = await createTestUser('SUPER_ADMIN')
+    userIds.push(admin.id)
+    const program = await createTestProgram({ name: `mentee-activity-${uid()}` })
+    programIds.push(program.id)
+
+    const lead = await createUserWithRoles('APPLICANT', ['APPLICANT'])
+    userIds.push(lead.id)
+    const mentor = await createUserWithRoles('MENTOR', ['MENTOR'])
+    userIds.push(mentor.id)
+
+    // Four projects all wantsMentorship
+    const pUnassigned = await createTestProject(program.id, { title: 'Unassigned' })
+    const pAssigned = await createTestProject(program.id, { title: 'Assigned' })
+    const pActive = await createTestProject(program.id, { title: 'Active' })
+    const pStalled = await createTestProject(program.id, { title: 'Stalled' })
+    for (const p of [pUnassigned, pAssigned, pActive, pStalled]) {
+      await prisma.project.update({ where: { id: p.id }, data: { wantsMentorship: true } })
+      await prisma.teamMember.create({
+        data: { projectId: p.id, userId: lead.id, role: 'LEAD' },
+      })
+    }
+
+    // Assigned: mentor assigned, no activity yet
+    await prisma.mentorAssignment.create({
+      data: {
+        projectId: pAssigned.id,
+        mentorId: mentor.id,
+        method: 'MANUAL',
+        assignedBy: admin.id,
+        workspaceEnabled: true,
+      },
+    })
+
+    // Active: mentor + recent message
+    const aActive = await prisma.mentorAssignment.create({
+      data: {
+        projectId: pActive.id,
+        mentorId: mentor.id,
+        method: 'MANUAL',
+        assignedBy: admin.id,
+        workspaceEnabled: true,
+      },
+    })
+    await prisma.mentorMessage.create({
+      data: {
+        projectId: pActive.id,
+        senderId: mentor.id,
+        message: 'recent ping',
+        workspaceId: aActive.id,
+        createdAt: new Date(Date.now() - 2 * DAY),
+      },
+    })
+
+    // Stalled: mentor + last message > 14 days ago
+    const aStalled = await prisma.mentorAssignment.create({
+      data: {
+        projectId: pStalled.id,
+        mentorId: mentor.id,
+        method: 'MANUAL',
+        assignedBy: admin.id,
+        workspaceEnabled: true,
+        assignedAt: new Date(Date.now() - 30 * DAY),
+      },
+    })
+    await prisma.mentorMessage.create({
+      data: {
+        projectId: pStalled.id,
+        senderId: mentor.id,
+        message: 'old ping',
+        workspaceId: aStalled.id,
+        createdAt: new Date(Date.now() - 20 * DAY),
+      },
+    })
+
+    const caller = createCaller(mentorRouter, {
+      id: admin.id,
+      email: admin.email,
+      role: 'SUPER_ADMIN',
+    })
+    const result = await caller.getMenteeActivity({ programId: program.id })
+
+    const byTitle = Object.fromEntries(
+      result.rows.map((r: (typeof result.rows)[number]) => [r.project.title, r]),
+    )
+    expect(byTitle['Unassigned'].status).toBe('unassigned')
+    expect(byTitle['Unassigned'].mentor).toBeNull()
+    expect(byTitle['Assigned'].status).toBe('assigned')
+    expect(byTitle['Assigned'].mentor?.id).toBe(mentor.id)
+    expect(byTitle['Active'].status).toBe('active')
+    expect(byTitle['Active'].lastActivityAt).not.toBeNull()
+    expect(byTitle['Stalled'].status).toBe('stalled')
+
+    expect(result.totals.unassigned).toBe(1)
+    expect(result.totals.assigned).toBe(1)
+    expect(result.totals.active).toBe(1)
+    expect(result.totals.stalled).toBe(1)
+
+    // Team lead resolved
+    expect(byTitle['Active'].teamLead?.email).toBe(lead.email)
+  })
+
+  it('only includes projects that wantMentorship within the program scope', async () => {
+    const admin = await createTestUser('SUPER_ADMIN')
+    userIds.push(admin.id)
+    const program = await createTestProgram({ name: `mentee-scope-${uid()}` })
+    programIds.push(program.id)
+
+    const pYes = await createTestProject(program.id, { title: 'Yes' })
+    const pNo = await createTestProject(program.id, { title: 'No' })
+    await prisma.project.update({ where: { id: pYes.id }, data: { wantsMentorship: true } })
+    await prisma.project.update({ where: { id: pNo.id }, data: { wantsMentorship: false } })
+
+    const caller = createCaller(mentorRouter, {
+      id: admin.id,
+      email: admin.email,
+      role: 'SUPER_ADMIN',
+    })
+    const result = await caller.getMenteeActivity({ programId: program.id })
+
+    expect(
+      result.rows.map((r: (typeof result.rows)[number]) => r.project.title).sort(),
+    ).toEqual(['Yes'])
+  })
+})