assets/js/booking.js

@@ -210,23 +210,84 @@
             </div>`;
     }
 
+    // Active private-lesson offerings per instructor, so revisiting the
+    // registration form does not refetch the same catalog.
+    const offeringCache = new Map();
+
+    function instructorOfferings(instructorId) {
+        if (offeringCache.has(instructorId)) {
+            return Promise.resolve(offeringCache.get(instructorId));
+        }
+        return apiFetch(`offerings?instructor_id=${instructorId}&kind=private_lesson`).then((list) => {
+            offeringCache.set(instructorId, list);
+            return list;
+        });
+    }
+
+    // "Piano Lesson (60 min — $50.00 CAD)" / "Trial Lesson (Free)"
+    function offeringLabel(o) {
+        const duration = o.duration_minutes ? `${o.duration_minutes} min — ` : '';
+        const price = Number(o.price) > 0
+            ? `$${Number(o.price).toFixed(2)} ${o.currency}`
+            : 'Free';
+        return `${o.title} (${duration}${price})`;
+    }
+
     function openRegistration(slot) {
         clearError();
 
-        const offeringId = Number(slot.offering_id) || 0;
-        const qPath = offeringId ? `offerings/${offeringId}/questions` : null;
-
         Promise.all([
-            qPath ? apiFetch(qPath) : Promise.resolve([]),
+            instructorOfferings(Number(slot.instructor_id)),
             apiFetch('policies?scope=booking'),
         ])
-            .then(([questions, policies]) => {
-                renderRegistration(slot, offeringId, questions, policies);
+            .then(([offerings, policies]) => {
+                renderRegistration(slot, offerings, policies);
             })
             .catch((err) => showError(err.message));
     }
 
-    function renderRegistration(slot, offeringId, questions, policies) {
+    function offeringFieldHtml(tied, tiedId, choices) {
+        if (tiedId) {
+            // The slot is tied to one offering: show it locked so the student
+            // sees exactly what they are booking.
+            const label = tied ? offeringLabel(tied) : `Offering #${tiedId}`;
+            return `
+                <p class="us-offering">
+                    <label>Lesson type<br>
+                    <select id="us-offering" disabled><option>${escHtml(label)}</option></select></label>
+                </p>`;
+        }
+        return `
+            <p class="us-offering">
+                <label>Lesson type<br>
+                <select id="us-offering" required>
+                    <option value="">— Choose a lesson type —</option>
+                    ${choices.map((o) => `<option value="${o.id}">${escHtml(offeringLabel(o))}</option>`).join('')}
+                </select></label>
+            </p>`;
+    }
+
+    function renderRegistration(slot, offerings, policies) {
+        const tiedId = Number(slot.offering_id) || 0;
+        const tied   = tiedId ? offerings.find((o) => Number(o.id) === tiedId) : null;
+
+        // Generic slots offer every lesson type that fits the slot's length.
+        const choices = tiedId
+            ? []
+            : offerings.filter((o) => !o.duration_minutes || Number(o.duration_minutes) === Number(slot.duration_minutes));
+
+        if (!tiedId && !choices.length) {
+            // The server rejects offering-less bookings, so without a matching
+            // lesson type this time cannot be booked online.
+            slotList.innerHTML = `
+                <div class="us-register">
+                    <p>This time cannot be booked online right now. Please contact the instructor.</p>
+                    <p><button type="button" id="us-cancel" class="us-cancel-btn">Back</button></p>
+                </div>`;
+            document.getElementById('us-cancel').addEventListener('click', loadSlots);
+            return;
+        }
+
         const weekly = slot.recurrence_group
             ? `<p><label><input type="checkbox" id="us-weekly"> Reserve this time weekly for the term</label></p>`
             : '';
@@ -235,7 +296,8 @@
             <div class="us-register">
                 <h3>${escHtml(dayLabel(dayKey(slot.start_dt)))} · ${escHtml(timeOf(slot.start_dt))}–${escHtml(timeOf(slot.end_dt))}</h3>
                 <form id="us-register-form">
-                    ${questions.map(questionField).join('')}
+                    ${offeringFieldHtml(tied, tiedId, choices)}
+                    <div id="us-questions"></div>
                     ${policies.map(policyField).join('')}
                     ${weekly}
                     <p>
@@ -245,10 +307,42 @@
                 </form>
             </div>`;
 
+        // The intake questions belong to the selected offering, so they follow
+        // the picker instead of being fixed at render time.
+        let selectedId = tiedId;
+        let questions  = [];
+
+        const questionsBox = document.getElementById('us-questions');
+
+        function loadQuestions() {
+            questions = [];
+            questionsBox.innerHTML = '';
+            if (!selectedId) return;
+            apiFetch(`offerings/${selectedId}/questions`)
+                .then((qs) => {
+                    questions = qs;
+                    questionsBox.innerHTML = qs.map(questionField).join('');
+                })
+                .catch((err) => showError(err.message));
+        }
+
+        if (!tiedId) {
+            document.getElementById('us-offering').addEventListener('change', (e) => {
+                selectedId = Number(e.target.value) || 0;
+                loadQuestions();
+            });
+        }
+
+        loadQuestions();
+
         document.getElementById('us-cancel').addEventListener('click', loadSlots);
         document.getElementById('us-register-form').addEventListener('submit', (e) => {
             e.preventDefault();
-            submitBooking(e.target, slot, offeringId, questions);
+            if (!selectedId) {
+                showError('Please choose a lesson type.');
+                return;
+            }
+            submitBooking(e.target, slot, selectedId, questions);
         });
     }
 

docs/features/lesson-booking.md

@@ -21,12 +21,12 @@ Students register for a private lesson by choosing an offering, picking a time (
 
 ## Registration Flow
 1. Student opens the page with the `[us_booking]` shortcode and browses open slots as an agenda list or a weekly calendar (view toggle with previous/next-week navigation; times shown in 12-hour AM/PM form).
-2. Student picks an **offering** (a 30 or 60-minute private-lesson type) and a slot.
+2. Student picks a slot and an **offering** (a 30 or 60-minute private-lesson type). When the slot is tied to an offering the form shows it locked (the student sees exactly what they are booking); otherwise the form presents the instructor's active private-lesson offerings whose duration fits the slot. Every booking requires an offering — a generic slot with no fitting offering cannot be booked online.
 3. For a `weekly` reservation, the same weekday/time is held for the rest of the offering's term.
 4. Student answers the offering's questions (`GET /offerings/{id}/questions`).
 5. Student accepts the current published policy versions (`GET /policies`) — required to continue.
 6. Payment is taken per the student's billing method (card by default; `pending` for e-transfer; skipped for comp). See `payments.md`.
-7. `POST /bookings` creates the lesson row(s) (`status = pending`), records answers and policy acceptances, marks `us_availability.is_booked = 1`, and links the payment. A booking with nothing owed (no offering, or a free offering) creates no payment and is `confirmed` immediately.
+7. `POST /bookings` creates the lesson row(s) (`status = pending`), records answers and policy acceptances, marks `us_availability.is_booked = 1`, and links the payment. A booking with nothing owed (a free offering) creates no payment and is `confirmed` immediately.
 8. On successful payment (or comp) the lesson is `confirmed` and a receipt is emailed.
 9. Instructor sees the booking under **My Lessons** and may update status via `PATCH /bookings/{id}/status`.
 10. The booking page also shows the student their upcoming lessons (`GET /bookings`) with a per-lesson status badge (pending payment / confirmed) and a **Cancel** button.
@@ -61,6 +61,11 @@ offering).
 `status`, and `payment` — a `{id, method, status}` summary, or `null` when
 nothing is owed (the front end then skips the payment step).
 
+An offering is always required (`400 offering_required` otherwise): a slot tied
+to an offering uses that offering regardless of the request, while a generic
+slot uses the student's `offering_id`, which must be one of the instructor's
+active `private_lesson` offerings whose `duration_minutes` matches the slot.
+
 `GET /bookings` returns the caller's upcoming, non-cancelled lessons (their own
 for students; the instructor's for callers with `manage_availability`), each
 with the slot's `start_dt`/`end_dt`.

src/Booking/BookingEndpoint.php

@@ -5,6 +5,7 @@ namespace Unsupervised\Schedular\Booking;
 
 use Unsupervised\Schedular\Availability\AvailabilityRepository;
 use Unsupervised\Schedular\Auth\RoleManager;
+use Unsupervised\Schedular\Offering\Offering;
 use Unsupervised\Schedular\Offering\OfferingRepository;
 use Unsupervised\Schedular\Payment\Payment;
 use Unsupervised\Schedular\Payment\PaymentService;
@@ -165,15 +166,35 @@ class BookingEndpoint {
 			$offeringId = $requestedOfferingId;
 		}
 
-		$offering = $offeringId > 0 ? $this->offerings->findById( $offeringId ) : null;
-		if ( $offeringId > 0 && null === $offering ) {
+		// Every lesson books against an offering: it carries the price, intake
+		// questions, and payment routing. Without one the booking would silently
+		// be free and unquestioned, so generic slots require the student's choice.
+		if ( $offeringId <= 0 ) {
+			return new \WP_Error( 'offering_required', __( 'Choose a lesson type to book this slot.', 'unsupervised-schedular' ), [ 'status' => 400 ] );
+		}
+
+		$offering = $this->offerings->findById( $offeringId );
+		if ( null === $offering ) {
 			return new \WP_Error( 'invalid_offering', __( 'Offering not found.', 'unsupervised-schedular' ), [ 'status' => 400 ] );
 		}
 
-		if ( null !== $offering && $offering->instructorId !== $slot->instructorId ) {
+		if ( $offering->instructorId !== $slot->instructorId ) {
 			return new \WP_Error( 'offering_mismatch', __( 'That offering is not available for this slot.', 'unsupervised-schedular' ), [ 'status' => 400 ] );
 		}
 
+		// A slot-tied offering was the instructor's explicit choice and is honoured
+		// as-is; a student-chosen one must be something the catalog actually offers
+		// for this slot: an active private-lesson type whose length fits the slot.
+		if ( 0 === $slotOfferingId ) {
+			if ( ! $offering->isActive || Offering::KIND_PRIVATE_LESSON !== $offering->kind ) {
+				return new \WP_Error( 'invalid_offering', __( 'That offering cannot be booked as a private lesson.', 'unsupervised-schedular' ), [ 'status' => 400 ] );
+			}
+
+			if ( null !== $offering->durationMinutes && $offering->durationMinutes !== $slot->durationMinutes ) {
+				return new \WP_Error( 'offering_mismatch', __( 'That offering does not match this slot\'s lesson length.', 'unsupervised-schedular' ), [ 'status' => 400 ] );
+			}
+		}
+
 		$answers            = $this->answers( $request );
 		$acceptedVersionIds = array_values( array_map( static fn( mixed $v ): int => absint( Val::int( $v ) ), (array) $request->get_param( 'accepted_policy_version_ids' ) ) );
 
@@ -192,7 +213,7 @@ class BookingEndpoint {
 			slotId:       $slotId,
 			studentId:    $studentId,
 			instructorId: $slot->instructorId,
-			offeringId:   $offeringId > 0 ? $offeringId : null,
+			offeringId:   $offeringId,
 			recurrence:   $recurrence,
 			notes:        '' !== $notes ? $notes : null,
 		);
@@ -227,14 +248,14 @@ class BookingEndpoint {
 		$payment = null;
 		$status  = Lesson::STATUS_PENDING;
 
-		if ( null !== $offering && $offering->price > 0.0 ) {
+		if ( $offering->price > 0.0 ) {
 			$payment = $this->payments->createForRegistration( Payment::REG_LESSON, $anchorId, $studentId, $slot->instructorId, $offering->price, $offering->currency, $offering->etransferEmail );
 
 			if ( null !== $payment && $payment->isPaid() ) {
 				$status = Lesson::STATUS_CONFIRMED;
 			}
 		} else {
-			// Nothing owed: there is no payment step that would confirm these
+			// Free offering: there is no payment step that would confirm these
 			// lessons later, so they are confirmed at booking time.
 			foreach ( $ids as $lessonId ) {
 				$this->bookings->updateStatus( $lessonId, Lesson::STATUS_CONFIRMED );

tests/Unit/Booking/BookingEndpointTest.php

@@ -98,13 +98,16 @@ class BookingEndpointTest extends TestCase
 
     public function testBookReturns409WhenSlotClaimFails(): void
     {
-        // Generic slot, no offering; another request wins the claim first.
+        // Generic slot; another request wins the claim first.
         $this->availability->shouldReceive('findById')->with(10)->andReturn($this->slot(10, 3, null));
+        $this->offerings->shouldReceive('findById')->with(8)->andReturn(
+            new Offering(instructorId: 3, kind: Offering::KIND_PRIVATE_LESSON, title: 'Lesson', price: 0.0, id: 8)
+        );
         $this->gate->shouldReceive('validate')->andReturn(null);
         $this->availability->shouldReceive('claim')->with(10)->once()->andReturn(false);
         $this->bookings->shouldNotReceive('insert');
 
-        $request = new \WP_REST_Request(['slot_id' => 10]);
+        $request = new \WP_REST_Request(['slot_id' => 10, 'offering_id' => 8]);
         $result  = $this->endpoint->book($request);
 
         self::assertInstanceOf(\WP_Error::class, $result);
@@ -135,22 +138,102 @@ class BookingEndpointTest extends TestCase
         self::assertNull($result->get_data()['payment']);
     }
 
-    public function testBookWithoutOfferingConfirmsImmediatelyWithNoPayment(): void
+    public function testBookWithoutOfferingIsRejected(): void
     {
+        // A booking with no offering would be silently free, so it must be refused.
         $this->availability->shouldReceive('findById')->with(10)->andReturn($this->slot(10, 3, null));
+        $this->offerings->shouldNotReceive('findById');
+        $this->availability->shouldNotReceive('claim');
+        $this->bookings->shouldNotReceive('insert');
+
+        $request = new \WP_REST_Request(['slot_id' => 10]);
+        $result  = $this->endpoint->book($request);
+
+        self::assertInstanceOf(\WP_Error::class, $result);
+        self::assertSame('offering_required', $result->get_error_code());
+    }
+
+    public function testBookUsesSlotTiedOfferingWhenRequestOmitsIt(): void
+    {
+        // Slot tied to offering 5: the booking must charge that offering even
+        // though the client sent no offering_id.
+        $this->availability->shouldReceive('findById')->with(10)->andReturn($this->slot(10, 3, 5));
+        $this->offerings->shouldReceive('findById')->with(5)->andReturn(
+            new Offering(instructorId: 3, kind: Offering::KIND_PRIVATE_LESSON, title: 'Lesson', price: 50.0, id: 5)
+        );
         $this->gate->shouldReceive('validate')->andReturn(null);
         $this->availability->shouldReceive('claim')->with(10)->once()->andReturn(true);
-        $this->bookings->shouldReceive('insert')->once()->andReturn(77);
+        $this->bookings->shouldReceive('insert')
+            ->once()
+            ->with(Mockery::on(static fn (Lesson $l): bool => 5 === $l->offeringId))
+            ->andReturn(77);
         $this->gate->shouldReceive('record')->once();
-        $this->payments->shouldNotReceive('createForRegistration');
-        $this->bookings->shouldReceive('updateStatus')->with(77, Lesson::STATUS_CONFIRMED)->once()->andReturn(true);
+        $this->payments->shouldReceive('createForRegistration')
+            ->once()
+            ->with(Payment::REG_LESSON, 77, 5, 3, 50.0, 'CAD', null)
+            ->andReturn(new Payment(
+                studentId:        5,
+                instructorId:     3,
+                registrationType: Payment::REG_LESSON,
+                registrationId:   77,
+                amount:           50.0,
+                method:           Payment::METHOD_ETRANSFER,
+                status:           Payment::STATUS_PENDING,
+                id:               12,
+            ));
+        $this->bookings->shouldNotReceive('updateStatus');
 
         $request = new \WP_REST_Request(['slot_id' => 10]);
         $result  = $this->endpoint->book($request);
 
         self::assertInstanceOf(\WP_REST_Response::class, $result);
-        self::assertSame(Lesson::STATUS_CONFIRMED, $result->get_data()['status']);
-        self::assertNull($result->get_data()['payment']);
+        self::assertSame(Lesson::STATUS_PENDING, $result->get_data()['status']);
+    }
+
+    public function testBookRejectsInactiveStudentChosenOffering(): void
+    {
+        $this->availability->shouldReceive('findById')->with(10)->andReturn($this->slot(10, 3, null));
+        $this->offerings->shouldReceive('findById')->with(8)->andReturn(
+            new Offering(instructorId: 3, kind: Offering::KIND_PRIVATE_LESSON, title: 'Retired', price: 50.0, isActive: false, id: 8)
+        );
+        $this->availability->shouldNotReceive('claim');
+
+        $request = new \WP_REST_Request(['slot_id' => 10, 'offering_id' => 8]);
+        $result  = $this->endpoint->book($request);
+
+        self::assertInstanceOf(\WP_Error::class, $result);
+        self::assertSame('invalid_offering', $result->get_error_code());
+    }
+
+    public function testBookRejectsGroupClassOfferingForLessonSlot(): void
+    {
+        $this->availability->shouldReceive('findById')->with(10)->andReturn($this->slot(10, 3, null));
+        $this->offerings->shouldReceive('findById')->with(8)->andReturn(
+            new Offering(instructorId: 3, kind: Offering::KIND_GROUP_CLASS, title: 'Choir', price: 10.0, id: 8)
+        );
+        $this->availability->shouldNotReceive('claim');
+
+        $request = new \WP_REST_Request(['slot_id' => 10, 'offering_id' => 8]);
+        $result  = $this->endpoint->book($request);
+
+        self::assertInstanceOf(\WP_Error::class, $result);
+        self::assertSame('invalid_offering', $result->get_error_code());
+    }
+
+    public function testBookRejectsOfferingWhoseDurationDoesNotFitSlot(): void
+    {
+        // Slot is 60 minutes (the helper default); a 30-minute offering cannot book it.
+        $this->availability->shouldReceive('findById')->with(10)->andReturn($this->slot(10, 3, null));
+        $this->offerings->shouldReceive('findById')->with(8)->andReturn(
+            new Offering(instructorId: 3, kind: Offering::KIND_PRIVATE_LESSON, title: 'Short', price: 25.0, durationMinutes: 30, id: 8)
+        );
+        $this->availability->shouldNotReceive('claim');
+
+        $request = new \WP_REST_Request(['slot_id' => 10, 'offering_id' => 8]);
+        $result  = $this->endpoint->book($request);
+
+        self::assertInstanceOf(\WP_Error::class, $result);
+        self::assertSame('offering_mismatch', $result->get_error_code());
     }
 
     public function testBookWithPricedOfferingStaysPendingAndReturnsPaymentSummary(): void