dashboard refactor: useHomeDashboardData (#3342)

* dashboard refactor phase 3: extract home dashboard view-model helpers

Move home-only data orchestration out of the home dashboard component
and into a typed composer (private function in HomeEnrollmentsDisplay.tsx)
that calls named pure helpers from model/dashboardViewModel.ts.

New pure helpers in dashboardViewModel.ts (with unit tests):
  bucketAndSortHomeEnrollments, enrollmentCourseIsInPrograms,
  groupModuleCoursesByProgramId, getModuleCourseIdsFromPrograms,
  getNonContractProgramEnrollments, getTopLevelProgramEnrollments,
  isProgramAsCourse, isNonContractEnrollment.

ProgramEnrollmentDisplay's two inline reduces (enrollmentsByCourseId,
programEnrollmentsById) now use the simplified helpers added in Phase 1.
Drop the dead courses parameter from groupCourseRunEnrollmentsByCourseId
— its filter never tripped because both callers only look up by ids the
helper would have included.

Soften the plan's "zero inline transforms" exit check across Phases 3-5
to "no inline-defined domain logic" — composing a named predicate or
comparator with .filter() is glue, not orchestration. Add an Open
question noting Phase 3 inlined useHomeDashboardData as a private
function rather than its own file; Phase 4/5 settle the hook location
and test strategy before they begin.

Rename ProgramContent.test.tsx's mock testid enrollment-display →
program-enrollment-display for clarity now that two dashboards exist.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* Add home dashboard B2B course filter test

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* dashboard refactor phase 3 v3: extract useHomeDashboardData hook + assembleHomeCardList

Set the consistent composer/testing pattern for the dashboard refactor
(Phases 4-5 follow it):

- Add pure assembleHomeCardList(buckets+programEnrollments) ->
  { cards, initiallyVisibleCount } owning home card ordering + the
  MIN_VISIBLE promotion rule (was stranded in EnrollmentExpandCollapse).
  Isolated unit tests in dashboardViewModel.test.ts.
- Move useHomeDashboardData out of HomeEnrollmentsDisplay.tsx into a
  separate exported hooks/useHomeDashboardData.ts; emits the durable
  contract { cards, initiallyVisibleCount, ... }.
- Add hooks/useHomeDashboardData.test.tsx renderHook suite reusing the
  shared setupEnrollments scenario (no duplicated mock setup).
- EnrollmentExpandCollapse reduced to zero-logic slice + toggle.
- HomeEnrollmentsDisplay.test.tsx left exactly untouched as the
  behavior-preservation oracle.
- Update dashboardRefactorPlan.md: resolve the hook location/testing
  open question, document Phase 3 v3, re-scope Phase 6 to a checkpoint,
  add overall testing-strategy section.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* address phase 3 v3 review feedback

- B#1: resolveSlotForLanguage calls local pickDisplayedEnrollmentForLegacyDashboard
  instead of round-tripping through helpers.selectBestEnrollment; drop the
  now-unused ../helpers import. Removes the gratuitous helpers<->viewModel
  cycle leg. Zero behavior change (resolveSlotForLanguage/Program/Contract
  suites green).
- A: add assembleHomeCardList case (nonExpired>0, no expired ->
  initiallyVisibleCount === cards.length), closing the case matrix.
- B#2: fix DashboardCourseSlot JSDoc typo.
- B#3: scope the type-only-import comment to that line (not a file-wide
  no-cycle claim).
- Rewrite useHomeDashboardData JSDoc: timeless/descriptive, drop the
  refactor-historical 'remains unchanged' framing.
- Plan: record the uniform durable-contract assertion rule (composer
  suites assert the durable contract, never through the adapter;
  displayed-*/run-selection pinned only in the resolveSlotForLanguage
  unit suite) so Phase 4/5 inherit it.

Oracle (HomeEnrollmentsDisplay.test.tsx) still untouched. Full
DashboardPage suite 411/411.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* plan: language-picker decided (hook owns it, Phase 4); fold reviewer-C refinements

- Resolved decision: language picker = option (b) — useDashboardLanguagePicker
  extracted in Phase 4, composed by useProgramDashboardData; component
  presentational. Rationale recorded (hook needs the key to build slots
  regardless, so the YAGNI-defer argument doesn't hold).
- Phase 4 pre-decisions block: (1) slot/adapter prove-or-delete, default
  lean (A) build it for real on Program; (2) test-utils infra-only +
  composable buildProgramScenario; (3) language picker (b).
- Phase 5: hard exit gate — no OrgProgramDisplay/OrgProgramCollectionDisplay
  inline resolveSlotForLanguage / b2b_contract_id filtering.
- Phase 7: checkbox to migrate DashboardResource/DashboardType into
  dashboardViewModel.ts before deleting DashboardCard.tsx.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* address gpt-5.4 review: doc accuracy + hook contract coverage

- A: scope the 'oracle untouched' wording in dashboardRefactorPlan.md.
  HomeEnrollmentsDisplay.test.tsx is NOT modified by the v3 extraction
  (empty diff for 8ec7d30^..HEAD), but it is new on this branch
  (created cf3c0db, extended d812730 in Phase 3 v1). Plan now says
  'not modified by the extraction commit' and flags the branch-vs-main
  narrative for reviewers, instead of a blanket 'untouched'.
- B: add a renderHook test asserting the durable contract fields
  courseProgramsById / moduleCoursesByProgramId (program-as-course
  lookups the renderer needs) — previously only covered indirectly via
  the component suite.
- C: no change. ProgramContent.test.tsx is modified on the branch only
  by a mechanical test-id rename in Phase 3 v1 (cf3c0db), forced by
  the EnrollmentDisplay->ProgramEnrollmentDisplay rename; its low-value
  nature is pre-existing and out of refactor scope.

Oracle still not modified by v3. Full DashboardPage suite 412/412.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* docs: correct adapter/slot wording in dashboard refactor plan

CoursewareCard consumes a per-row variant union, never a slot — fix the
two 'consumes the slot directly' phrasings (lines 214, 731) that
contradicted the Phase 7 variant-union design and stability rule. Also
fix two stale spots that drifted from the Resolved decision: the layer
table's composer-location cell and the net-file-count reading note
(Phase 3 v3 added a hooks/ directory of separate exported composers).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* docs: correct layer-2 assertion rule for displayedEnrollment/displayedRun

The old rule banned displayedEnrollment/displayedRun from composer
renderHook suites and pinned them only in the pure resolveSlotForLanguage
suite — but those fields are returned, render-driving contract, and a
returned field that is 'wrong' to assert is a smell. The pure suite
proves the derivation; it cannot catch wiring (hook feeding the resolver
wrong-scoped enrollments or a stale language key). Split by which bug
each layer catches: composer suite asserts a representative
displayedEnrollment/displayedRun (wiring); pure suite owns the exhaustive
language-resolution matrix (derivation). Drop the stale 'only durable'
framing in the lead-in accordingly.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: 3 people

frontends/main/src/app-pages/DashboardPage/CoursewareDisplay/HomeEnrollmentsDisplay.test.tsx

@@ -57,6 +57,46 @@ describe("HomeEnrollmentsDisplay", () => {
     })
   })
 
+  test("Renders one card per enrollment when a single course has multiple enrollments", async () => {
+    const mitxOnlineUser = mitxonline.factories.user.user()
+    setMockResponse.get(mitxonline.urls.userMe.get(), mitxOnlineUser)
+
+    const sharedCourseId = faker.number.int()
+    const enrollmentA = mitxonline.factories.enrollment.courseEnrollment({
+      run: {
+        title: "Same Course — Run A",
+        course: { id: sharedCourseId },
+      },
+    })
+    const enrollmentB = mitxonline.factories.enrollment.courseEnrollment({
+      run: {
+        title: "Same Course — Run B",
+        course: { id: sharedCourseId },
+      },
+    })
+
+    setMockResponse.get(mitxonline.urls.enrollment.enrollmentsListV3(), [
+      enrollmentA,
+      enrollmentB,
+    ])
+    setMockResponse.get(
+      mitxonline.urls.programEnrollments.enrollmentsListV3(),
+      [],
+    )
+
+    renderWithProviders(<HomeEnrollmentsDisplay />)
+
+    await screen.findByRole("heading", { name: "My Learning" })
+    const cards = await screen.findAllByTestId("enrollment-card-desktop")
+    expect(cards).toHaveLength(2)
+    expect(
+      cards.find((c) => c.textContent?.includes("Same Course — Run A")),
+    ).toBeDefined()
+    expect(
+      cards.find((c) => c.textContent?.includes("Same Course — Run B")),
+    ).toBeDefined()
+  })
+
   test("Renders the proper amount of unenroll and email settings buttons in the context menus", async () => {
     const { enrollments } = setupApis()
     renderWithProviders(<HomeEnrollmentsDisplay />)
@@ -779,6 +819,47 @@ describe("HomeEnrollmentsDisplay", () => {
     expect(screen.queryByText(b2bSimpleProgram.title)).not.toBeInTheDocument()
   })
 
+  test("Filters B2B course enrollments from display", async () => {
+    const mitxOnlineUser = mitxonline.factories.user.user()
+    setMockResponse.get(mitxonline.urls.userMe.get(), mitxOnlineUser)
+
+    mockedUseFeatureFlagEnabled.mockReturnValue(true)
+
+    const b2bEnrollment = mitxonline.factories.enrollment.courseEnrollment({
+      b2b_contract_id: 42,
+      run: {
+        title: "B2B Hidden Course",
+        course: { title: "B2B Hidden Course" },
+      },
+    })
+    const nonB2BEnrollment = mitxonline.factories.enrollment.courseEnrollment({
+      b2b_contract_id: null,
+      run: {
+        title: "Personal Visible Course",
+        course: { title: "Personal Visible Course" },
+      },
+    })
+
+    setMockResponse.get(mitxonline.urls.enrollment.enrollmentsListV3(), [
+      b2bEnrollment,
+      nonB2BEnrollment,
+    ])
+    setMockResponse.get(
+      mitxonline.urls.programEnrollments.enrollmentsListV3(),
+      [],
+    )
+
+    renderWithProviders(<HomeEnrollmentsDisplay />)
+
+    await screen.findByRole("heading", { name: "My Learning" })
+
+    const personalCourseCards = await screen.findAllByText(
+      nonB2BEnrollment.run.title,
+    )
+    expect(personalCourseCards.length).toBeGreaterThan(0)
+    expect(screen.queryByText(b2bEnrollment.run.title)).not.toBeInTheDocument()
+  })
+
   test("Hides child program enrollments that are part of an enrolled parent program", async () => {
     const mitxOnlineUser = mitxonline.factories.user.user()
     setMockResponse.get(mitxonline.urls.userMe.get(), mitxOnlineUser)