Add group-class scheduling, instructor assignment, and details/invite management

Group classes now carry a specific class time (alongside date and duration)
and an assigned instructor:

- Schema: add `class_time` (TIME) to `us_offerings`; `Offering` gains
  `normalizeTime`/`sessionWindows`. (Rides the pending 1.0.0->1.1.0 dbDelta
  upgrade, so no version bump.)
- Offering form: class-time field, plus a studio-admin instructor picker
  (plain instructors always own their own classes).
- `ClassSlotReconciler`: assigning an instructor clears their open booking
  slots overlapping each session and flags already-booked lessons that clash
  (a booked lesson is never deleted). Uses new
  `AvailabilityRepository::findOverlapping`.
- Front end: `GET /offerings` exposes `instructor_name`; the enrolment page
  shows who teaches each class and when it meets.

Back-office group-class views redesigned:

- Instructor **My Group Classes** and studio-admin **Group Classes** are now
  per-class summaries with enrolment counts, not flat student lists.
- Each links through (`?class_id=<id>`) to a per-class **details page**
  (schedule panel, roster with payment status, and — for invite-only classes
  — the add/make-available/invite-by-email controls). Invite-only membership
  is managed entirely from this page.
- Invite actions are allowed for the class's owning instructor or any
  `view_all_lessons` studio admin, so an owner-operator (studio admin who also
  teaches) can reach every class's roster and invites from the Group Classes
  page.

Tests: composer test (508), composer lint, composer cs all pass.

Co-Authored-By: Claude Opus 4.8 <[email protected]>

src/GroupClass/GroupClassController.php

@@ -27,33 +27,76 @@ class GroupClassController {
 		private RegistrationMailer $mailer,
 	) {}
 
+	/**
+	 * Studio-admin overview: every group class across instructors as a summary —
+	 * who teaches it, when it meets, and how full it is — rather than a flat list
+	 * of individual student enrolments. Selecting a class (`?class_id=<id>`) opens
+	 * the same per-class details page instructors use, so a studio admin (including
+	 * an owner-operator who also teaches) can view any class's roster and manage
+	 * invite-only membership from here.
+	 */
 	public function renderPage(): void {
 		if ( ! current_user_can( RoleManager::CAP_VIEW_ALL_LESSONS ) ) {
 			wp_die( esc_html__( 'You do not have permission to view group classes.', 'unsupervised-schedular' ) );
 		}
 
+		$notice = '';
+		if ( isset( $_POST['usc_action'] ) && check_admin_referer( 'usc_group_action' ) ) {
+			$notice = $this->handleFormAction( get_current_user_id() );
+		}
+
+		$offerings = $this->offerings->findAll( 0, Offering::KIND_GROUP_CLASS );
+		$baseUrl   = admin_url( 'admin.php?page=us-group-classes' );
+
+		// View-state query param only (which class to drill into) — nothing is
+		// mutated from it, so no nonce applies.
+		// phpcs:ignore WordPress.Security.NonceVerification.Recommended
+		$classId = absint( Val::int( $_GET['class_id'] ?? 0 ) );
+		$current = null;
+		foreach ( $offerings as $offering ) {
+			if ( $offering->id === $classId ) {
+				$current = $offering;
+				break;
+			}
+		}
+
+		if ( null !== $current ) {
+			// Enrolments are looked up by the class's own instructor; classDetail
+			// filters them down to this offering.
+			$class    = $this->classDetail( $current, $this->enrollments->findByInstructor( $current->instructorId ) );
+			$students = $this->studentOptions();
+
+			include USC_PLUGIN_DIR . 'templates/admin/my-group-class-detail.php';
+
+			return;
+		}
+
 		$rows = array_map(
-			function ( Enrollment $enrollment ): array {
-				$offering = $this->offerings->findById( $enrollment->offeringId );
-				$student  = get_userdata( $enrollment->studentId );
+			function ( Offering $offering ): array {
+				$instructor = get_userdata( $offering->instructorId );
 
 				return [
-					'student'  => $student ? $student->display_name : (string) $enrollment->studentId,
-					'offering' => $offering ? $offering->title : (string) $enrollment->offeringId,
-					'status'   => $enrollment->status,
+					'id'          => $offering->id,
+					'title'       => $offering->title,
+					'instructor'  => $instructor ? $instructor->display_name : (string) $offering->instructorId,
+					'when'        => $this->whenLabel( $offering ),
+					'capacity'    => $offering->capacity,
+					'enrolled'    => $this->enrollments->countActiveForOffering( (int) $offering->id ),
+					'invite_only' => $offering->isInviteOnly(),
 				];
 			},
-			$this->enrollments->findAllActive()
+			$offerings
 		);
 
 		include USC_PLUGIN_DIR . 'templates/admin/group-classes.php';
 	}
 
 	/**
-	 * Instructor view: their own group classes with per-class rosters. Each class
-	 * shows its enrolment count against capacity plus a roster of enrolled
-	 * students with enrolment and payment status. Invite-only classes also carry
-	 * controls to add, grant access to, or email-invite students.
+	 * Instructor view. By default a summary of the instructor's own group classes
+	 * — each with when it meets and how many are enrolled — rather than a dump of
+	 * every roster. A `class_id` query param drills into one class to show its
+	 * roster of enrolled students and, for invite-only classes, the controls to
+	 * add, grant access to, or email-invite students.
 	 */
 	public function renderInstructorPage(): void {
 		if ( ! current_user_can( RoleManager::CAP_VIEW_LESSONS ) ) {
@@ -67,50 +110,127 @@ class GroupClassController {
 			$notice = $this->handleFormAction( $instructorId );
 		}
 
+		$offerings   = $this->offerings->findAll( $instructorId, Offering::KIND_GROUP_CLASS );
 		$enrollments = $this->enrollments->findByInstructor( $instructorId );
 
+		// View-state query param only (which class to drill into) — nothing is
+		// mutated from it, so no nonce applies.
+		// phpcs:ignore WordPress.Security.NonceVerification.Recommended
+		$classId = absint( Val::int( $_GET['class_id'] ?? 0 ) );
+		$current = null;
+		foreach ( $offerings as $offering ) {
+			if ( $offering->id === $classId ) {
+				$current = $offering;
+				break;
+			}
+		}
+
+		if ( null !== $current ) {
+			$baseUrl  = admin_url( 'admin.php?page=us-my-group-classes' );
+			$class    = $this->classDetail( $current, $enrollments );
+			$students = $this->studentOptions();
+
+			include USC_PLUGIN_DIR . 'templates/admin/my-group-class-detail.php';
+
+			return;
+		}
+
 		$classes = array_map(
-			function ( Offering $offering ) use ( $enrollments ): array {
-				$roster   = [];
-				$enrolled = 0;
-
-				foreach ( $enrollments as $enrollment ) {
-					if ( $enrollment->offeringId !== $offering->id ) {
-						continue;
-					}
-
-					if ( Enrollment::STATUS_ACTIVE === $enrollment->status ) {
-						++$enrolled;
-					}
-
-					$student = get_userdata( $enrollment->studentId );
-					$payment = null !== $enrollment->paymentId ? $this->payments->findById( $enrollment->paymentId ) : null;
-
-					$roster[] = [
-						'student' => $student ? $student->display_name : (string) $enrollment->studentId,
-						'status'  => $enrollment->status,
-						'payment' => $payment?->status,
-					];
-				}
-
-				return [
-					'id'          => $offering->id,
-					'title'       => $offering->title,
-					'capacity'    => $offering->capacity,
-					'enrolled'    => $enrolled,
-					'invite_only' => $offering->isInviteOnly(),
-					'roster'      => $roster,
-					'invited'     => $offering->isInviteOnly() ? $this->pendingInvites( (int) $offering->id ) : [],
-				];
-			},
-			$this->offerings->findAll( $instructorId, Offering::KIND_GROUP_CLASS )
+			fn( Offering $offering ): array => $this->classSummary( $offering, $enrollments ),
+			$offerings
 		);
 
-		$students = $this->studentOptions();
+		$baseUrl = admin_url( 'admin.php?page=us-my-group-classes' );
 
 		include USC_PLUGIN_DIR . 'templates/admin/my-group-classes.php';
 	}
 
+	/**
+	 * Summary row for one class in the instructor overview: its identity, when it
+	 * meets, and how many active enrolments it holds against capacity.
+	 *
+	 * @param list<Enrollment> $enrollments
+	 * @return array{id: int|null, title: string, when: string, capacity: int|null, enrolled: int, invite_only: bool}
+	 */
+	private function classSummary( Offering $offering, array $enrollments ): array {
+		$enrolled = 0;
+		foreach ( $enrollments as $enrollment ) {
+			if ( $enrollment->offeringId === $offering->id && Enrollment::STATUS_ACTIVE === $enrollment->status ) {
+				++$enrolled;
+			}
+		}
+
+		return [
+			'id'          => $offering->id,
+			'title'       => $offering->title,
+			'when'        => $this->whenLabel( $offering ),
+			'capacity'    => $offering->capacity,
+			'enrolled'    => $enrolled,
+			'invite_only' => $offering->isInviteOnly(),
+		];
+	}
+
+	/**
+	 * Full details for one class: the summary fields, the class's own settings
+	 * (instructor, price, duration, description, schedule, active state), the
+	 * roster of enrolled students (with enrolment and payment status), and — for
+	 * invite-only classes — the list of people invited but not yet enrolled.
+	 *
+	 * @param list<Enrollment> $enrollments
+	 * @return array{id: int|null, title: string, when: string, capacity: int|null, enrolled: int, invite_only: bool, instructor: string, price: float, currency: string, duration: int|null, description: string|null, schedule_note: string|null, active: bool, roster: list<array{student: string, status: string, payment: string|null}>, invited: list<array{who: string, kind: string}>}
+	 */
+	private function classDetail( Offering $offering, array $enrollments ): array {
+		$roster = [];
+		foreach ( $enrollments as $enrollment ) {
+			if ( $enrollment->offeringId !== $offering->id ) {
+				continue;
+			}
+
+			$student = get_userdata( $enrollment->studentId );
+			$payment = null !== $enrollment->paymentId ? $this->payments->findById( $enrollment->paymentId ) : null;
+
+			$roster[] = [
+				'student' => $student ? $student->display_name : (string) $enrollment->studentId,
+				'status'  => $enrollment->status,
+				'payment' => $payment?->status,
+			];
+		}
+
+		$instructor = get_userdata( $offering->instructorId );
+
+		return $this->classSummary( $offering, $enrollments ) + [
+			'instructor'    => $instructor ? $instructor->display_name : (string) $offering->instructorId,
+			'price'         => $offering->price,
+			'currency'      => $offering->currency,
+			'duration'      => $offering->durationMinutes,
+			'description'   => $offering->description,
+			'schedule_note' => $offering->scheduleNote,
+			'active'        => $offering->isActive,
+			'roster'        => $roster,
+			'invited'       => $offering->isInviteOnly() ? $this->pendingInvites( (int) $offering->id ) : [],
+		];
+	}
+
+	/**
+	 * Human-readable "when" label for a class: the class date (or weekly date
+	 * range) and, when set, the start time. Empty when the class has no date.
+	 */
+	private function whenLabel( Offering $offering ): string {
+		if ( null === $offering->termStart ) {
+			return '';
+		}
+
+		$label = null === $offering->termEnd || $offering->termEnd === $offering->termStart
+			? (string) mysql2date( 'M j, Y', $offering->termStart )
+			: (string) mysql2date( 'M j, Y', $offering->termStart ) . ' – ' . (string) mysql2date( 'M j, Y', $offering->termEnd );
+
+		if ( null !== $offering->classTime ) {
+			$label .= ' · ' . (string) mysql2date( 'g:i a', $offering->termStart . ' ' . $offering->classTime );
+		}
+
+		return $label;
+	}
+
 	/**
 	 * Pending (not-yet-enrolled) access grants for an invite-only class, shown so
 	 * the instructor can see who has been invited but has not enrolled yet.
@@ -143,7 +263,10 @@ class GroupClassController {
 
 	/**
 	 * Handle a posted management action, returning a status notice for display.
-	 * Every action is scoped to a group class the current instructor owns.
+	 * The action is scoped to a group class the current instructor owns, unless
+	 * the caller is a studio admin (`view_all_lessons`) — who may manage any
+	 * instructor's class, since the studio-admin Group Classes page reaches the
+	 * same controls for every class.
 	 */
 	private function handleFormAction( int $instructorId ): string {
 		// Nonce is verified by the caller before this method runs.
@@ -152,7 +275,10 @@ class GroupClassController {
 		$offeringId = absint( Val::int( $_POST['offering_id'] ?? 0 ) );
 		$offering   = $offeringId > 0 ? $this->offerings->findById( $offeringId ) : null;
 
-		if ( null === $offering || $offering->instructorId !== $instructorId || Offering::KIND_GROUP_CLASS !== $offering->kind ) {
+		$ownsOrManagesAll = null !== $offering
+			&& ( $offering->instructorId === $instructorId || current_user_can( RoleManager::CAP_VIEW_ALL_LESSONS ) );
+
+		if ( null === $offering || ! $ownsOrManagesAll || Offering::KIND_GROUP_CLASS !== $offering->kind ) {
 			return esc_html__( 'That group class was not found.', 'unsupervised-schedular' );
 		}