<?php
declare(strict_types=1);

namespace Unsupervised\Schedular\Auth;

use Unsupervised\Schedular\Availability\AvailabilityRepository;
use Unsupervised\Schedular\Booking\BookingRepository;
use Unsupervised\Schedular\Booking\Lesson;
use Unsupervised\Schedular\GroupClass\Enrollment;
use Unsupervised\Schedular\GroupClass\EnrollmentRepository;
use Unsupervised\Schedular\Payment\PaymentService;

/**
 * Studio-admin actions on a single student from the student detail view:
 * cancelling a lesson, withdrawing a group-class enrolment, and editing basic
 * account details. Mutations go through the same paths as the student-facing
 * flows so slot release and pending-payment voiding stay consistent.
 */
class StudentActions {

	public function __construct(
		private BookingRepository $bookings,
		private AvailabilityRepository $availability,
		private EnrollmentRepository $enrollments,
		private PaymentService $payments,
	) {}

	/**
	 * Cancel a lesson on the student's behalf: marks it cancelled, frees the
	 * slot for rebooking, and voids a still-pending payment. A paid lesson is
	 * credited back to the student's account (a per-lesson share of what they
	 * paid) to offset their future scheduled billing.
	 */
	public function cancelLesson( int $lessonId, int $studentId ): bool {
		$lesson = $this->bookings->findById( $lessonId );

		if ( null === $lesson || $lesson->studentId !== $studentId || Lesson::STATUS_CANCELLED === $lesson->status ) {
			return false;
		}

		$this->bookings->updateStatus( $lessonId, Lesson::STATUS_CANCELLED );
		$this->availability->release( $lesson->slotId );
		$this->payments->voidPending( $lesson->paymentId );
		$this->payments->creditForCancelledLesson( $lesson );

		return true;
	}

	/**
	 * Withdraw the student from a group class: marks the active enrolment
	 * cancelled (freeing its capacity seat) and voids a still-pending payment.
	 */
	public function withdrawEnrollment( int $enrollmentId, int $studentId ): bool {
		$enrollment = $this->enrollments->findById( $enrollmentId );

		if ( null === $enrollment || $enrollment->studentId !== $studentId || Enrollment::STATUS_ACTIVE !== $enrollment->status ) {
			return false;
		}

		$this->enrollments->updateStatus( $enrollmentId, Enrollment::STATUS_CANCELLED );
		$this->payments->voidPending( $enrollment->paymentId );

		return true;
	}

	/**
	 * Update the student's display name and email. The email must be valid and
	 * not belong to another user.
	 */
	public function updateAccount( int $studentId, string $displayName, string $email ): bool|\WP_Error {
		if ( '' === $displayName ) {
			return new \WP_Error( 'empty_name', __( 'Display name cannot be empty.', 'unsupervised-schedular' ) );
		}

		if ( ! is_email( $email ) ) {
			return new \WP_Error( 'invalid_email', __( 'Please enter a valid email address.', 'unsupervised-schedular' ) );
		}

		$existing = email_exists( $email );
		if ( false !== $existing && (int) $existing !== $studentId ) {
			return new \WP_Error( 'email_taken', __( 'Another account already uses this email address.', 'unsupervised-schedular' ) );
		}

		$result = wp_update_user(
			[
				'ID'           => $studentId,
				'display_name' => $displayName,
				'user_email'   => $email,
			]
		);

		return $result instanceof \WP_Error ? $result : true;
	}
}