<?php

declare(strict_types=1);

namespace App\Service;

use App\BusProNet\DataProcessor\BookingDataProcessor;
use App\BusProNet\Model\Booking;
use App\BusProNet\Model\Pickup;
use App\BusProNet\Model\Service;
use App\Form\Model\BookingDto;
use App\Form\Model\ParticipantDto;
use App\Form\Service\Condition\TravelStartCutoffReachedCondition;

/**
 * Enforces immutable edit categories before submitting booking updates.
 *
 * This guard reconciles the in-session edit DTO with a fresh booking snapshot.
 * If a mutability cutoff passed during an edit session, stale user changes in
 * immutable categories are reverted to the current booking state so update
 * payloads cannot include blocked changes.
 */
class BookingEditSubmitGuard
{
    public function __construct(
        private readonly BookingDataProcessor $bookingDataProcessor,
    ) {
    }

    /**
     * Reverts immutable category changes to fresh booking values.
     *
     * @return bool True when at least one immutable field was reverted
     */
    public function reconcileImmutableCategories(BookingDto $workingDto, Booking $freshBooking): bool
    {
        $baselineDto = $this->bookingDataProcessor->createBookingDtoFromBooking($freshBooking, $workingDto->travel, $workingDto->isInternalAgencyBooking());
        // Booking-level D-4 cutoff used as submit-time safety net for rentals.
        $serviceCutoffReachedCondition = new TravelStartCutoffReachedCondition(
            TravelStartCutoffReachedCondition::DEFAULT_DAYS_BEFORE_START
        );
        // TravelStartCutoffReachedCondition is booking-level (travel date only).
        // The interface requires a participant index, but this condition does not use it,
        // so we pass 0 as a neutral placeholder.
        $rentalsLockedByCutoff = $serviceCutoffReachedCondition->evaluate($workingDto, 0, []);

        $changed = false;

        foreach ($workingDto->participants as $index => $participant) {
            $baseline = $baselineDto->participants[$index] ?? null;
            if (null === $baseline) {
                continue;
            }

            if (false === $workingDto->travel->additionalServicesMutable) {
                $changed = $this->reconcileAdditionalServices($participant, $baseline) || $changed;
            }

            // Reconcile rentals either when BPN additional services are immutable
            // or when our D-4 rule has been reached.
            if (false === $workingDto->travel->additionalServicesMutable || $rentalsLockedByCutoff) {
                $changed = $this->reconcileRentals($participant, $baseline) || $changed;
            }

            if (false === $workingDto->travel->transportationServicesMutable) {
                $changed = $this->reconcileTransportationServices($participant, $baseline) || $changed;
            }

            if (false === $workingDto->travel->pickupsMutable) {
                $changed = $this->reconcilePickups($participant, $baseline) || $changed;
            }
        }

        return $changed;
    }

    private function reconcileAdditionalServices(ParticipantDto $participant, ParticipantDto $baseline): bool
    {
        $changed = false;

        if (false === $this->areServiceListsEqual($participant->courses, $baseline->courses)) {
            $participant->courses = $baseline->courses;
            $changed = true;
        }

        if (false === $this->areServiceListsEqual($participant->additionalServices, $baseline->additionalServices)) {
            $participant->additionalServices = $baseline->additionalServices;
            $changed = true;
        }

        if (false === $this->areServiceListsEqual($participant->board, $baseline->board)) {
            $participant->board = $baseline->board;
            $changed = true;
        }

        if (false === $this->isSameService($participant->veg, $baseline->veg)) {
            $participant->veg = $baseline->veg;
            $changed = true;
        }

        if (false === $this->isSameService($participant->skiPass, $baseline->skiPass)) {
            $participant->skiPass = $baseline->skiPass;
            $changed = true;
        }

        if (false === $this->isSameService($participant->rentalInsurance, $baseline->rentalInsurance)) {
            $participant->rentalInsurance = $baseline->rentalInsurance;
            $changed = true;
        }

        if ($participant->rentalInsuranceSelected !== $baseline->rentalInsuranceSelected) {
            $participant->rentalInsuranceSelected = $baseline->rentalInsuranceSelected;
            $changed = true;
        }

        return $changed;
    }

    private function reconcileRentals(ParticipantDto $participant, ParticipantDto $baseline): bool
    {
        if (false === $this->areServiceListsEqual($participant->rentals, $baseline->rentals)) {
            $participant->rentals = $baseline->rentals;

            return true;
        }

        return false;
    }

    private function reconcileTransportationServices(ParticipantDto $participant, ParticipantDto $baseline): bool
    {
        $changed = false;

        if (false === $this->isSameService($participant->transportationOutbound, $baseline->transportationOutbound)) {
            $participant->transportationOutbound = $baseline->transportationOutbound;
            $changed = true;
        }

        if (false === $this->isSameService($participant->transportationInbound, $baseline->transportationInbound)) {
            $participant->transportationInbound = $baseline->transportationInbound;
            $changed = true;
        }

        if ($participant->parking !== $baseline->parking) {
            $participant->parking = $baseline->parking;
            $changed = true;
        }

        if (false === $this->isSameService($participant->parkingService, $baseline->parkingService)) {
            $participant->parkingService = $baseline->parkingService;
            $changed = true;
        }

        return $changed;
    }

    private function reconcilePickups(ParticipantDto $participant, ParticipantDto $baseline): bool
    {
        $changed = false;

        if (false === $this->isSamePickup($participant->pickup, $baseline->pickup)) {
            $participant->pickup = $baseline->pickup;
            $changed = true;
        }

        if (false === $this->isSamePickup($participant->dropOff, $baseline->dropOff)) {
            $participant->dropOff = $baseline->dropOff;
            $changed = true;
        }

        if ($participant->differentDropOff !== $baseline->differentDropOff) {
            $participant->differentDropOff = $baseline->differentDropOff;
            $changed = true;
        }

        return $changed;
    }

    /**
     * @param list<Service> $left
     * @param list<Service> $right
     */
    private function areServiceListsEqual(array $left, array $right): bool
    {
        return $this->normalizeServiceIds($left) === $this->normalizeServiceIds($right);
    }

    /**
     * @param Service[] $services
     *
     * @return int[]
     */
    private function normalizeServiceIds(array $services): array
    {
        $ids = [];
        foreach ($services as $service) {
            $ids[] = $service->id;
        }

        $ids = array_values(array_unique($ids));
        sort($ids);

        return $ids;
    }

    private function isSameService(?Service $left, ?Service $right): bool
    {
        return $left?->id === $right?->id;
    }

    private function isSamePickup(?Pickup $left, ?Pickup $right): bool
    {
        return $left?->id === $right?->id;
    }
}