Add lesson booking registration flow (offering, questions, policies)

Implements #3: students register for a private lesson by picking a slot,
answering the offering's intake questions, and accepting booking-scoped
policies. Payment is a clean seam for #7 (lessons land pending; payment_id
null; instructor confirms via PATCH /bookings/{id}/status).

- Schema: us_lessons += offering_id, recurrence, series_id, payment_id.
- Lesson: new fields + recurrence constants.
- BookingRepository::insertSeries() builds a weekly series sharing a
  series_id; AvailabilityRepository::findUnbookedInGroup() reserves a group.
- RegistrationGate (src/Registration/): validate + record intake answers and
  booking-scoped policy acceptances. Reused by group enrolment (#4).
- BookingEndpoint::book(): offering_id, recurrence, answers,
  accepted_policy_version_ids; single or weekly; records answers/acceptances
  (type lesson).
- GET /policies?scope=booking filter.
- Front-end booking.js: slot -> questions + policies -> submit.
- Wiring: RegistrationGate built in Plugin, passed via RestRegistrar.
- Test-only WP_Error stub in tests/bootstrap.php for gate testing.

Refs #3

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/Availability/AvailabilityRepository.php

@@ -141,6 +141,22 @@ class AvailabilityRepository {
 		return array_map( AvailabilitySlot::fromRow( ... ), $rows ?? [] );
 	}
 
+	/**
+	 * Unbooked slots that belong to a weekly-recurring group, ordered by start.
+	 *
+	 * @return list<AvailabilitySlot>
+	 */
+	public function findUnbookedInGroup( int $recurrenceGroup ): array {
+		$rows = $this->db->get_results(
+			$this->db->prepare(
+				"SELECT * FROM {$this->table} WHERE recurrence_group = %d AND is_booked = 0 ORDER BY start_dt ASC",
+				$recurrenceGroup
+			)
+		);
+
+		return array_map( AvailabilitySlot::fromRow( ... ), $rows ?? [] );
+	}
+
 	public function findById( int $id ): ?AvailabilitySlot {
 		$row = $this->db->get_row(
 			$this->db->prepare( "SELECT * FROM {$this->table} WHERE id = %d", $id )

src/Booking/BookingEndpoint.php

@@ -5,12 +5,17 @@ namespace Unsupervised\Schedular\Booking;
 
 use Unsupervised\Schedular\Availability\AvailabilityRepository;
 use Unsupervised\Schedular\Auth\RoleManager;
+use Unsupervised\Schedular\Offering\OfferingRepository;
+use Unsupervised\Schedular\Policy\PolicyAcceptance;
+use Unsupervised\Schedular\Registration\RegistrationGate;
 
 class BookingEndpoint {
 
 	public function __construct(
 		private AvailabilityRepository $availability,
 		private BookingRepository $bookings,
+		private OfferingRepository $offerings,
+		private RegistrationGate $gate,
 	) {}
 
 	public function registerRoutes( string $route_namespace ): void {
@@ -28,12 +33,28 @@ class BookingEndpoint {
 					'callback'            => [ $this, 'book' ],
 					'permission_callback' => [ $this, 'canBook' ],
 					'args'                => [
-						'slot_id' => [
+						'slot_id'                     => [
 							'type'              => 'integer',
 							'required'          => true,
 							'sanitize_callback' => 'absint',
 						],
-						'notes'   => [
+						'offering_id'                 => [
+							'type'    => 'integer',
+							'default' => 0,
+						],
+						'recurrence'                  => [
+							'type'    => 'string',
+							'default' => 'single',
+						],
+						'answers'                     => [
+							'type'    => 'object',
+							'default' => [],
+						],
+						'accepted_policy_version_ids' => [
+							'type'    => 'array',
+							'default' => [],
+						],
+						'notes'                       => [
 							'type'              => 'string',
 							'default'           => '',
 							'sanitize_callback' => 'sanitize_textarea_field',
@@ -84,26 +105,83 @@ class BookingEndpoint {
 			return new \WP_Error( 'slot_taken', __( 'This slot is already booked.', 'unsupervised-schedular' ), [ 'status' => 409 ] );
 		}
 
-		$notes  = (string) $request->get_param( 'notes' );
-		$lesson = new Lesson(
+		$offeringId = absint( $request->get_param( 'offering_id' ) );
+		if ( 0 === $offeringId ) {
+			$offeringId = (int) ( $slot->offeringId ?? 0 );
+		}
+		if ( $offeringId > 0 && null === $this->offerings->findById( $offeringId ) ) {
+			return new \WP_Error( 'invalid_offering', __( 'Offering not found.', 'unsupervised-schedular' ), [ 'status' => 400 ] );
+		}
+
+		$answers            = $this->answers( $request );
+		$acceptedVersionIds = array_map( 'absint', (array) $request->get_param( 'accepted_policy_version_ids' ) );
+
+		$gateError = $this->gate->validate( $offeringId, $answers, $acceptedVersionIds );
+		if ( $gateError instanceof \WP_Error ) {
+			return $gateError;
+		}
+
+		$studentId  = get_current_user_id();
+		$notes      = (string) $request->get_param( 'notes' );
+		$recurrence = Lesson::RECURRENCE_WEEKLY === $request->get_param( 'recurrence' )
+			? Lesson::RECURRENCE_WEEKLY
+			: Lesson::RECURRENCE_SINGLE;
+
+		$template = new Lesson(
 			slotId:       $slotId,
-			studentId:    get_current_user_id(),
+			studentId:    $studentId,
 			instructorId: $slot->instructorId,
+			offeringId:   $offeringId > 0 ? $offeringId : null,
+			recurrence:   $recurrence,
 			notes:        '' !== $notes ? $notes : null,
 		);
 
-		$id = $this->bookings->insert( $lesson );
-		$this->availability->markBooked( $slotId );
+		// Weekly reservation across the slot's recurring group; otherwise a single lesson.
+		if ( Lesson::RECURRENCE_WEEKLY === $recurrence && null !== $slot->recurrenceGroup ) {
+			$slotIds = array_map( static fn( $s ): int => (int) $s->id, $this->availability->findUnbookedInGroup( $slot->recurrenceGroup ) );
+			$ids     = $this->bookings->insertSeries( $template, $slotIds );
+			foreach ( $slotIds as $reservedSlotId ) {
+				$this->availability->markBooked( $reservedSlotId );
+			}
+			$anchorId = $ids[0] ?? 0;
+		} else {
+			$anchorId = $this->bookings->insert( $template );
+			$this->availability->markBooked( $slotId );
+			$ids = [ $anchorId ];
+		}
+
+		$this->gate->record( PolicyAcceptance::REG_LESSON, $anchorId, $studentId, $offeringId, $answers, $acceptedVersionIds, $this->clientIp() );
 
 		return new \WP_REST_Response(
 			[
-				'id'     => $id,
+				'ids'    => $ids,
 				'status' => Lesson::STATUS_PENDING,
 			],
 			201
 		);
 	}
 
+	/**
+	 * Extract a question_id => value map from the request.
+	 *
+	 * @return array<int, string>
+	 */
+	private function answers( \WP_REST_Request $request ): array {
+		$out = [];
+		foreach ( (array) $request->get_param( 'answers' ) as $questionId => $value ) {
+			$out[ (int) $questionId ] = sanitize_text_field( (string) $value );
+		}
+
+		return $out;
+	}
+
+	private function clientIp(): ?string {
+		// phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized, WordPress.Security.ValidatedSanitizedInput.MissingUnslash -- IP stored verbatim for audit.
+		$ip = sanitize_text_field( wp_unslash( $_SERVER['REMOTE_ADDR'] ?? '' ) );
+
+		return '' !== $ip ? $ip : null;
+	}
+
 	public function updateStatus( \WP_REST_Request $request ): \WP_REST_Response|\WP_Error {
 		$id     = absint( $request->get_param( 'id' ) );
 		$lesson = $this->bookings->findById( $id );

src/Booking/BookingRepository.php

@@ -16,18 +16,68 @@ class BookingRepository {
 			$this->table,
 			[
 				'slot_id'       => $lesson->slotId,
+				'offering_id'   => $lesson->offeringId,
 				'student_id'    => $lesson->studentId,
 				'instructor_id' => $lesson->instructorId,
+				'recurrence'    => $lesson->recurrence,
+				'series_id'     => $lesson->seriesId,
 				'status'        => $lesson->status,
+				'payment_id'    => $lesson->paymentId,
 				'notes'         => $lesson->notes,
 				'created_at'    => current_time( 'mysql' ),
 			],
-			[ '%d', '%d', '%d', '%s', '%s', '%s' ]
+			[ '%d', '%d', '%d', '%d', '%s', '%d', '%s', '%d', '%s', '%s' ]
 		);
 
 		return $this->db->insert_id;
 	}
 
+	/**
+	 * Create a weekly lesson series — one lesson per slot, all sharing a
+	 * `series_id` (the id of the first lesson row).
+	 *
+	 * @param list<int> $slotIds Availability slot IDs to reserve, in order.
+	 * @return list<int> Inserted lesson IDs.
+	 */
+	public function insertSeries( Lesson $template, array $slotIds ): array {
+		$ids      = [];
+		$seriesId = 0;
+
+		foreach ( $slotIds as $slotId ) {
+			$id = $this->insert(
+				new Lesson(
+					slotId:       $slotId,
+					studentId:    $template->studentId,
+					instructorId: $template->instructorId,
+					offeringId:   $template->offeringId,
+					recurrence:   Lesson::RECURRENCE_WEEKLY,
+					seriesId:     $seriesId > 0 ? $seriesId : null,
+					status:       $template->status,
+					notes:        $template->notes,
+				)
+			);
+
+			if ( 0 === $seriesId ) {
+				$seriesId = $id;
+				$this->setSeriesId( $id, $seriesId );
+			}
+
+			$ids[] = $id;
+		}
+
+		return $ids;
+	}
+
+	private function setSeriesId( int $id, int $seriesId ): void {
+		$this->db->update(
+			$this->table,
+			[ 'series_id' => $seriesId ],
+			[ 'id' => $id ],
+			[ '%d' ],
+			[ '%d' ]
+		);
+	}
+
 	public function findById( int $id ): ?Lesson {
 		$row = $this->db->get_row(
 			$this->db->prepare( "SELECT * FROM {$this->table} WHERE id = %d", $id )

src/Booking/Lesson.php

@@ -16,11 +16,25 @@ class Lesson {
 	 */
 	public const VALID_STATUSES = [ self::STATUS_PENDING, self::STATUS_CONFIRMED, self::STATUS_CANCELLED ];
 
+	public const RECURRENCE_SINGLE = 'single';
+	public const RECURRENCE_WEEKLY = 'weekly';
+
+	/**
+	 * All valid recurrence values.
+	 *
+	 * @var list<string>
+	 */
+	public const VALID_RECURRENCES = [ self::RECURRENCE_SINGLE, self::RECURRENCE_WEEKLY ];
+
 	public function __construct(
 		public readonly int $slotId,
 		public readonly int $studentId,
 		public readonly int $instructorId,
+		public readonly ?int $offeringId = null,
+		public readonly string $recurrence = self::RECURRENCE_SINGLE,
+		public readonly ?int $seriesId = null,
 		public readonly string $status = self::STATUS_PENDING,
+		public readonly ?int $paymentId = null,
 		public readonly ?string $notes = null,
 		public readonly ?int $id = null,
 	) {}
@@ -30,7 +44,11 @@ class Lesson {
 			slotId:       (int) $row->slot_id,
 			studentId:    (int) $row->student_id,
 			instructorId: (int) $row->instructor_id,
+			offeringId:   null !== $row->offering_id ? (int) $row->offering_id : null,
+			recurrence:   $row->recurrence,
+			seriesId:     null !== $row->series_id ? (int) $row->series_id : null,
 			status:       $row->status,
+			paymentId:    null !== $row->payment_id ? (int) $row->payment_id : null,
 			notes:        $row->notes,
 			id:           (int) $row->id,
 		);
@@ -45,9 +63,13 @@ class Lesson {
 		return [
 			'id'            => $this->id,
 			'slot_id'       => $this->slotId,
+			'offering_id'   => $this->offeringId,
 			'student_id'    => $this->studentId,
 			'instructor_id' => $this->instructorId,
+			'recurrence'    => $this->recurrence,
+			'series_id'     => $this->seriesId,
 			'status'        => $this->status,
+			'payment_id'    => $this->paymentId,
 			'notes'         => $this->notes,
 		];
 	}

src/Plugin.php

@@ -12,7 +12,9 @@ use Unsupervised\Schedular\Policy\AcceptanceRepository;
 use Unsupervised\Schedular\Policy\PolicyRepository;
 use Unsupervised\Schedular\Policy\PolicyService;
 use Unsupervised\Schedular\Policy\PolicyVersionRepository;
+use Unsupervised\Schedular\Registration\AnswerRepository;
 use Unsupervised\Schedular\Registration\QuestionRepository;
+use Unsupervised\Schedular\Registration\RegistrationGate;
 
 class Plugin {
 
@@ -20,19 +22,21 @@ class Plugin {
 		load_plugin_textdomain( 'unsupervised-schedular', false, dirname( plugin_basename( USC_PLUGIN_FILE ) ) . '/languages' );
 
 		global $wpdb;
-		$availability   = new AvailabilityRepository( $wpdb );
-		$bookings       = new BookingRepository( $wpdb );
-		$offerings      = new OfferingRepository( $wpdb );
-		$questions      = new QuestionRepository( $wpdb );
-		$policies       = new PolicyRepository( $wpdb );
-		$policyVersions = new PolicyVersionRepository( $wpdb );
-		$policyService  = new PolicyService( $policies, $policyVersions );
-		$acceptances    = new AcceptanceRepository( $wpdb );
-		$invites        = new InviteRepository( $wpdb );
+		$availability     = new AvailabilityRepository( $wpdb );
+		$bookings         = new BookingRepository( $wpdb );
+		$offerings        = new OfferingRepository( $wpdb );
+		$questions        = new QuestionRepository( $wpdb );
+		$answers          = new AnswerRepository( $wpdb );
+		$policies         = new PolicyRepository( $wpdb );
+		$policyVersions   = new PolicyVersionRepository( $wpdb );
+		$policyService    = new PolicyService( $policies, $policyVersions );
+		$acceptances      = new AcceptanceRepository( $wpdb );
+		$invites          = new InviteRepository( $wpdb );
+		$registrationGate = new RegistrationGate( $questions, $answers, $policies, $policyVersions, $acceptances );
 
 		( new RoleManager() )->register();
 		( new AdminMenu( $availability, $bookings, $offerings, $questions, $policies, $policyVersions, $policyService, $invites ) )->register();
-		( new RestRegistrar( $availability, $bookings, $offerings, $questions, $policies, $policyVersions, $policyService ) )->register();
+		( new RestRegistrar( $availability, $bookings, $offerings, $questions, $policies, $policyVersions, $policyService, $registrationGate ) )->register();
 		( new ShortcodeRegistrar( $invites, $policies, $policyVersions, $acceptances ) )->register();
 	}
 }

src/Policy/PolicyEndpoint.php

@@ -69,12 +69,19 @@ class PolicyEndpoint {
 	}
 
 	/**
-	 * Public: the current published version of every policy (the registration gate).
+	 * Public: the current published version of every policy (the registration
+	 * gate). Pass `?scope=signup|booking` to limit to that gate (includes
+	 * `both`-scoped policies).
 	 */
-	public function index(): \WP_REST_Response {
+	public function index( \WP_REST_Request $request ): \WP_REST_Response {
+		$scope    = (string) $request->get_param( 'scope' );
+		$policies = in_array( $scope, [ Policy::SCOPE_SIGNUP, Policy::SCOPE_BOOKING ], true )
+			? $this->policies->findForScope( $scope )
+			: $this->policies->findAll();
+
 		$out = [];
 
-		foreach ( $this->policies->findAll() as $policy ) {
+		foreach ( $policies as $policy ) {
 			if ( null === $policy->currentVersionId ) {
 				continue;
 			}

src/Registration/RegistrationGate.php

@@ -0,0 +1,120 @@
+<?php
+declare(strict_types=1);
+
+namespace Unsupervised\Schedular\Registration;
+
+use Unsupervised\Schedular\Policy\AcceptanceRepository;
+use Unsupervised\Schedular\Policy\Policy;
+use Unsupervised\Schedular\Policy\PolicyAcceptance;
+use Unsupervised\Schedular\Policy\PolicyRepository;
+use Unsupervised\Schedular\Policy\PolicyVersionRepository;
+
+/**
+ * Shared registration gate: validates and records the intake-question answers
+ * and booking-scoped policy acceptances common to lesson bookings and group
+ * enrolments.
+ */
+class RegistrationGate {
+
+	public function __construct(
+		private QuestionRepository $questions,
+		private AnswerRepository $answers,
+		private PolicyRepository $policies,
+		private PolicyVersionRepository $versions,
+		private AcceptanceRepository $acceptances,
+	) {}
+
+	/**
+	 * Validate that required questions are answered and all booking-scoped
+	 * published policies are accepted. Returns null when the gate passes.
+	 *
+	 * @param array<int, string> $answers            question_id => answer value
+	 * @param list<int>          $acceptedVersionIds Accepted policy version IDs
+	 */
+	public function validate( int $offeringId, array $answers, array $acceptedVersionIds ): ?\WP_Error {
+		foreach ( $this->questions->findByOffering( $offeringId, true ) as $question ) {
+			if ( $question->isRequired && '' === trim( (string) ( $answers[ (int) $question->id ] ?? '' ) ) ) {
+				return new \WP_Error(
+					'missing_answer',
+					__( 'Please answer all required questions.', 'unsupervised-schedular' ),
+					[ 'status' => 400 ]
+				);
+			}
+		}
+
+		foreach ( $this->requiredPolicyVersionIds() as $versionId ) {
+			if ( ! in_array( $versionId, $acceptedVersionIds, true ) ) {
+				return new \WP_Error(
+					'policy_required',
+					__( 'You must accept all required policies.', 'unsupervised-schedular' ),
+					[ 'status' => 400 ]
+				);
+			}
+		}
+
+		return null;
+	}
+
+	/**
+	 * Persist answers and policy acceptances for a created registration.
+	 *
+	 * @param array<int, string> $answers            question_id => answer value
+	 * @param list<int>          $acceptedVersionIds Accepted policy version IDs
+	 */
+	public function record( string $registrationType, int $registrationId, int $studentId, int $offeringId, array $answers, array $acceptedVersionIds, ?string $ipAddress = null ): void {
+		foreach ( $this->questions->findByOffering( $offeringId, true ) as $question ) {
+			$value = (string) ( $answers[ (int) $question->id ] ?? '' );
+			if ( '' === $value ) {
+				continue;
+			}
+
+			$this->answers->insert(
+				new Answer(
+					questionId:       (int) $question->id,
+					registrationType: $registrationType,
+					registrationId:   $registrationId,
+					studentId:        $studentId,
+					answerValue:      $value,
+				)
+			);
+		}
+
+		foreach ( $this->requiredPolicyVersionIds() as $versionId ) {
+			if ( ! in_array( $versionId, $acceptedVersionIds, true ) ) {
+				continue;
+			}
+
+			$this->acceptances->insert(
+				new PolicyAcceptance(
+					policyVersionId:  $versionId,
+					studentId:        $studentId,
+					registrationType: $registrationType,
+					registrationId:   $registrationId,
+					ipAddress:        $ipAddress,
+				)
+			);
+		}
+	}
+
+	/**
+	 * Current published version IDs of every booking-scoped policy.
+	 *
+	 * @return list<int>
+	 */
+	private function requiredPolicyVersionIds(): array {
+		$ids = [];
+
+		foreach ( $this->policies->findForScope( Policy::SCOPE_BOOKING ) as $policy ) {
+			if ( null === $policy->currentVersionId ) {
+				continue;
+			}
+
+			$version = $this->versions->findById( $policy->currentVersionId );
+			if ( null !== $version && $version->isPublished() ) {
+				$ids[] = (int) $version->id;
+			}
+		}
+
+		return $ids;
+	}
+}

src/RestRegistrar.php

@@ -15,6 +15,7 @@ use Unsupervised\Schedular\Policy\PolicyService;
 use Unsupervised\Schedular\Policy\PolicyVersionRepository;
 use Unsupervised\Schedular\Registration\QuestionEndpoint;
 use Unsupervised\Schedular\Registration\QuestionRepository;
+use Unsupervised\Schedular\Registration\RegistrationGate;
 
 class RestRegistrar {
 
@@ -26,9 +27,9 @@ class RestRegistrar {
 	private QuestionEndpoint $questionEndpoint;
 	private PolicyEndpoint $policyEndpoint;
 
-	public function __construct( AvailabilityRepository $availability, BookingRepository $bookings, OfferingRepository $offerings, QuestionRepository $questions, PolicyRepository $policies, PolicyVersionRepository $policyVersions, PolicyService $policyService ) {
+	public function __construct( AvailabilityRepository $availability, BookingRepository $bookings, OfferingRepository $offerings, QuestionRepository $questions, PolicyRepository $policies, PolicyVersionRepository $policyVersions, PolicyService $policyService, RegistrationGate $gate ) {
 		$this->availabilityEndpoint = new AvailabilityEndpoint( $availability );
-		$this->bookingEndpoint      = new BookingEndpoint( $availability, $bookings );
+		$this->bookingEndpoint      = new BookingEndpoint( $availability, $bookings, $offerings, $gate );
 		$this->offeringEndpoint     = new OfferingEndpoint( $offerings );
 		$this->questionEndpoint     = new QuestionEndpoint( $questions, $offerings );
 		$this->policyEndpoint       = new PolicyEndpoint( $policies, $policyVersions, $policyService );

src/Schema.php

@@ -32,15 +32,21 @@ class Schema {
 			"CREATE TABLE {$prefix}us_lessons (
                 id            BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
                 slot_id       BIGINT UNSIGNED NOT NULL,
+                offering_id   BIGINT UNSIGNED DEFAULT NULL,
                 student_id    BIGINT UNSIGNED NOT NULL,
                 instructor_id BIGINT UNSIGNED NOT NULL,
+                recurrence    VARCHAR(10)     NOT NULL DEFAULT 'single',
+                series_id     BIGINT UNSIGNED DEFAULT NULL,
                 status        VARCHAR(20)     NOT NULL DEFAULT 'pending',
+                payment_id    BIGINT UNSIGNED DEFAULT NULL,
                 notes         TEXT,
                 created_at    DATETIME        NOT NULL,
                 PRIMARY KEY (id),
                 KEY slot_id (slot_id),
+                KEY offering_id (offering_id),
                 KEY student_id (student_id),
-                KEY instructor_id (instructor_id)
+                KEY instructor_id (instructor_id),
+                KEY series_id (series_id)
             ) {$charset};",
 
 			"CREATE TABLE {$prefix}us_offerings (