<?php

declare(strict_types=1);

namespace App\BusProNet\DataProcessor;

use App\BusProNet\Constants;
use App\BusProNet\Model\Communication;
use App\Form\Model\BookingCreateDto;
use App\Form\Model\BookingEditDto;

/**
 * Processes booking form data and converts it into BusProNet API payload format.
 *
 * This processor handles the complex transformation of booking edit form data into the structured
 * array format required by the BusProNet API. It manages service mappings between participants
 * and various booking components like additional services, transportation, and accommodations.
 * The processor ensures data consistency by resetting and rebuilding participant-to-service
 * mappings based on form selections, while maintaining proper API payload structure.
 */
class BookingDataProcessor
{
    /**
     * Creates an update request payload for the BusProNet API from booking form data.
     *
     * This method processes booking edit form data and transforms it into the structured array
     * format expected by the BusProNet XML API. It handles service mappings, participant data
     * updates, and generates the complete payload structure including booking metadata,
     * participant information, services, transportation, and accommodation details.
     *
     * The process involves:
     * - Resetting existing service-to-participant mappings
     * - Rebuilding mappings based on current form selections
     * - Adding new services from travel data when participants select them
     * - Removing services with no participant mappings
     * - Updating participant personal data from form input
     * - Synchronizing applicant data with first participant details
     * - Building the final API payload structure
     *
     * @param BookingEditDto|null $formData The booking edit form data containing updated participant and service selections
     *
     * @return array The structured payload array ready for BusProNet API submission
     */
    public function createUpdateRequestPayload(?BookingEditDto $formData): array
    {
        $bookingData = $formData->booking;
        $travelData = $formData->travel;

        $this->resetServiceMappings($bookingData);

        foreach ($formData->participants as $participant) {
            $this->processParticipantServices($participant, $bookingData, $travelData);
        }

        $this->removeUnusedServices($bookingData);
        $this->updateParticipantPersonalData($formData->participants, $bookingData);
        $this->syncApplicantData($bookingData);

        $payload = $this->buildBasePayload($bookingData);
        $this->addBankAccountToPayload($payload, $bookingData);
        $this->buildParticipantPayload($payload, $bookingData);
        $this->buildServicesPayload($payload, $bookingData);
        $this->buildPickupPayload($payload, $bookingData);

        return $payload;
    }

    /**
     * Resets all existing participant-to-service mappings to start with a clean slate.
     *
     * This ensures that service assignments are rebuilt from scratch based on current form selections.
     * Includes resetting room mappings to allow room reassignments during edit.
     *
     * @param object $bookingData The booking data object containing services to reset
     */
    private function resetServiceMappings(object $bookingData): void
    {
        $servicesToReset = [
            ...$bookingData->additionalServices,
            ...$bookingData->transportationServices,
            ...$bookingData->pickupsOutbound,
            ...$bookingData->pickupsInbound,
            ...$bookingData->rooms,
        ];

        foreach ($servicesToReset as $service) {
            $service->mapping = [];
        }
    }

    /**
     * Processes all services for a single participant.
     *
     * This orchestrator method handles the complete service assignment workflow for one participant,
     * including additional services, transportation services, pickup locations, and room assignments.
     *
     * @param object $participant The participant data from the form
     * @param object $bookingData The booking data object to update
     * @param object $travelData  The travel data containing available services
     */
    private function processParticipantServices(object $participant, object $bookingData, object $travelData): void
    {
        if (true === $participant->isCanceled()) {
            return;
        }

        $this->processAdditionalServices($participant, $bookingData, $travelData);
        $this->processTransportationServices($participant, $bookingData, $travelData);
        $this->processPickupLocations($participant, $bookingData);
        $this->processRoomAssignment($participant, $bookingData);
    }

    /**
     * Processes additional services for a participant.
     *
     * Maps additional services (courses, ski passes, board options, rentals) to the participant.
     * Adds new services to the booking if they don't already exist and sets individual pricing.
     *
     * @param object $participant The participant data from the form
     * @param object $bookingData The booking data object to update
     * @param object $travelData  The travel data containing available services
     */
    private function processAdditionalServices(object $participant, object $bookingData, object $travelData): void
    {
        $servicesToMap = [
            ...$participant->courses,
            ...$participant->additionalServices,
            ...$participant->board,
            ...$participant->rentals,
        ];

        // Add ski pass if selected (single service, not an array)
        if (null !== $participant->skiPass) {
            $servicesToMap[] = $participant->skiPass;
        }

        foreach ($servicesToMap as $service) {
            if (false === isset($bookingData->additionalServices[$service->id])) {
                $serviceToAdd = $travelData->additionalServices[$service->id] ?? null;
                if (null !== $serviceToAdd) {
                    $bookingData->additionalServices[$service->id] = $serviceToAdd;
                    $bookingData->additionalServices[$service->id]->individualPrice[$participant->index] = $serviceToAdd->price;
                }
            }
            $bookingData->additionalServices[$service->id]->mapping[] = $participant->index;
        }
    }

    /**
     * Processes transportation services for a participant.
     *
     * Maps transportation services (both directions: to and from destination) to the participant.
     * Adds new transportation services to the booking if they don't already exist.
     *
     * @param object $participant The participant data from the form
     * @param object $bookingData The booking data object to update
     * @param object $travelData  The travel data containing available services
     */
    private function processTransportationServices(object $participant, object $bookingData, object $travelData): void
    {
        foreach ([$participant->transportationOutbound, $participant->transportationInbound] as $service) {
            if (false === isset($bookingData->transportationServices[$service->id])) {
                $serviceToAdd = $travelData->transportationServices[$service->id] ?? null;
                if (null !== $serviceToAdd) {
                    $bookingData->transportationServices[$service->id] = $serviceToAdd;
                    $bookingData->transportationServices[$service->id]->individualPrice[$participant->index] = $serviceToAdd->price;
                }
            }
            $bookingData->transportationServices[$service->id]->mapping[] = $participant->index;
        }
    }

    /**
     * Processes pickup locations for participants using bus transportation.
     *
     * Only processes pickup locations for bus transportation services and maps the participant
     * to their selected pickup location.
     *
     * @param object $participant The participant data from the form
     * @param object $bookingData The booking data object to update
     */
    private function processPickupLocations(object $participant, object $bookingData): void
    {
        // Check if either transportation direction is BUS and pickup is selected
        $hasOutboundBus = null !== $participant->transportationOutbound && 'BUS' === $participant->transportationOutbound->subType;
        $hasInboundBus = null !== $participant->transportationInbound && 'BUS' === $participant->transportationInbound->subType;

        if (($hasOutboundBus || $hasInboundBus) && null !== $selectedPickup = $participant->pickup) {
            if (false === isset($bookingData->pickupsOutbound[$selectedPickup->id])) {
                $bookingData->pickupsOutbound[$selectedPickup->id] = $selectedPickup;
            }
            $bookingData->pickupsOutbound[$selectedPickup->id]->mapping[] = $participant->index;
        }
    }

    /**
     * Processes room assignment for a participant.
     *
     * Maps the participant to their assigned room. Allows room reassignment during
     * booking edits while maintaining the constraint that participants can only be
     * assigned to room types that have already been booked.
     *
     * @param object $participant The participant data from the form
     * @param object $bookingData The booking data object to update
     */
    private function processRoomAssignment(object $participant, object $bookingData): void
    {
        if (null === $participant->assignedRoomId) {
            return;
        }

        // Find the room in the existing booking by ID
        foreach ($bookingData->rooms as $room) {
            if ($room->id === $participant->assignedRoomId) {
                $room->mapping[] = $participant->index;
                break;
            }
        }
    }

    /**
     * Removes services and pickups with no participant mappings.
     *
     * Cleans up unused services to prevent empty services from being sent to the API.
     * This includes additional services, transportation services, and pickup locations.
     *
     * @param object $bookingData The booking data object to clean up
     */
    private function removeUnusedServices(object $bookingData): void
    {
        foreach ($bookingData->additionalServices as $service) {
            if (0 === count($service->mapping)) {
                unset($bookingData->additionalServices[$service->id]);
            }
        }

        foreach ($bookingData->transportationServices as $service) {
            if (0 === count($service->mapping)) {
                unset($bookingData->transportationServices[$service->id]);
            }
        }

        foreach ($bookingData->pickupsOutbound as $pickup) {
            if (0 === count($pickup->mapping)) {
                unset($bookingData->pickupsOutbound[$pickup->id]);
            }
        }

        foreach ($bookingData->pickupsInbound as $pickup) {
            if (0 === count($pickup->mapping)) {
                unset($bookingData->pickupsInbound[$pickup->id]);
            }
        }
    }

    /**
     * Updates participant personal data from form input.
     *
     * Only processes participants with status 'F' (active/confirmed participants).
     * Updates all personal data fields and communication information.
     *
     * @param array  $participants The participants array from the form
     * @param object $bookingData  The booking data object to update
     */
    private function updateParticipantPersonalData(array $participants, object $bookingData): void
    {
        foreach ($participants as $participant) {
            if ('F' !== $participant->status) {
                continue;
            }

            $bookingData->participants[$participant->index]->firstName = $participant->firstName;
            $bookingData->participants[$participant->index]->name = $participant->lastName;
            $bookingData->participants[$participant->index]->dateOfBirth = $participant->dateOfBirth;
            $bookingData->participants[$participant->index]->gender = $participant->gender;
            $bookingData->participants[$participant->index]->nationality = $participant->nationality;
            $bookingData->participants[$participant->index]->height = $participant->height;
            $bookingData->participants[$participant->index]->weight = $participant->weight;
            $bookingData->participants[$participant->index]->shoeSize = $participant->shoeSize;

            if ($participant->email || $participant->mobile) {
                if (null === $bookingData->participants[$participant->index]->communication) {
                    $bookingData->participants[$participant->index]->communication = new Communication();
                }
                $bookingData->participants[$participant->index]->communication->email = $participant->email;
                $bookingData->participants[$participant->index]->communication->mobile = $participant->mobile;
            }
        }
    }

    /**
     * Synchronizes applicant data with first participant's physical characteristics.
     *
     * The applicant (booking holder) inherits physical data from the first participant.
     *
     * @param object $bookingData The booking data object to update
     */
    private function syncApplicantData(object $bookingData): void
    {
        if (false !== $firstParticipant = reset($bookingData->participants)) {
            $bookingData->applicant->height = $firstParticipant->height;
            $bookingData->applicant->weight = $firstParticipant->weight;
            $bookingData->applicant->shoeSize = $firstParticipant->shoeSize;
        }
    }

    /**
     * Builds the base API payload structure with booking information.
     *
     * Creates the main structure that will be populated with detailed data sections.
     *
     * @param object $bookingData The booking data object
     *
     * @return array The base payload structure
     */
    private function buildBasePayload(object $bookingData): array
    {
        return [
            'idbuchung' => $bookingData->id,
            'status' => $bookingData->status,
            'idagentur' => $bookingData->agencyId,
            'idreise' => $bookingData->dateId,
            'idpartner' => $bookingData->hotelId,
            'anmelder' => $bookingData->applicant->toPayload(),
            'zahlung' => [
                '@idzahlungsart' => $bookingData->paymentId,
                '@bezeichnung' => $bookingData->paymentLabel,
                '@art' => $bookingData->paymentType,
            ],
            'teilnehmerliste' => [
                'teilnehmer' => [],
            ],
            'zusatzleistungen' => [
                'zusatzleistung' => [],
            ],
            'beförderungen' => [
                'beförderung' => [],
            ],
            'ferienzielunterbringungen' => [
                'ferienzielunterbringung' => [],
            ],
        ];
    }

    /**
     * Adds bank account information to the payload if present.
     *
     * Bank account information is required for direct debit payments.
     *
     * @param array  $payload     The payload array to modify
     * @param object $bookingData The booking data object
     */
    private function addBankAccountToPayload(array &$payload, object $bookingData): void
    {
        if (null !== $bookingData->bankAccount) {
            $payload['zahlung']['bankverbindung'] = [
                '@kreditinstitut' => $bookingData->bankAccount->bankName,
                '@iban' => $bookingData->bankAccount->iban,
                '@bic' => $bookingData->bankAccount->bic,
                '@kontoinhaber' => $bookingData->bankAccount->holder,
            ];
        }
    }

    /**
     * Builds the participant list section of the payload.
     *
     * Includes status and personal data for each participant.
     *
     * @param array  $payload     The payload array to modify
     * @param object $bookingData The booking data object
     */
    private function buildParticipantPayload(array &$payload, object $bookingData): void
    {
        foreach ($bookingData->participants as $index => $participant) {
            $payload['teilnehmerliste']['teilnehmer'][] = [
                '@id' => $index + 1,
                'status' => $bookingData->participantsStatus[$index],
                ...$participant->toPayload(),
            ];
        }
    }

    /**
     * Builds the services sections of the payload.
     *
     * Includes additional services, transportation services, and accommodation details
     * with participant mappings and quantities.
     *
     * @param array  $payload     The payload array to modify
     * @param object $bookingData The booking data object
     */
    private function buildServicesPayload(array &$payload, object $bookingData): void
    {
        foreach ($bookingData->additionalServices as $service) {
            $payload['zusatzleistungen']['zusatzleistung'][] = [
                '@idleistung' => $service->id,
                '@anzahl' => count($service->mapping),
                '@zuordnung' => implode(',', array_map(fn ($index) => $index + 1, $service->mapping)),
            ];
        }

        foreach ($bookingData->transportationServices as $service) {
            $payload['beförderungen']['beförderung'][] = [
                '@idleistung' => $service->id,
                '@anzahl' => count($service->mapping),
                '@zuordnung' => implode(',', array_map(fn ($index) => $index + 1, $service->mapping)),
            ];
        }

        foreach ($bookingData->rooms as $room) {
            $payload['ferienzielunterbringungen']['ferienzielunterbringung'][] = [
                '@idzimmer' => $room->id,
                '@kategorie' => $room->category,
                '@idverpflegung' => $room->boardId,
                '@anreise' => $room->dateFrom ? $room->dateFrom->format('d.m.Y') : null,
                '@abreise' => $room->dateTo ? $room->dateTo->format('d.m.Y') : null,
                '@anzahl' => $room->totalCount,
                '@zuordnung' => implode(',', array_map(fn ($index) => $index + 1, $room->mapping)),
            ];
        }
    }

    /**
     * Builds the pickup locations section of the payload.
     *
     * Only included in payload if there are actual pickup assignments for bus transportation.
     *
     * @param array  $payload     The payload array to modify
     * @param object $bookingData The booking data object
     */
    private function buildPickupPayload(array &$payload, object $bookingData): void
    {
        if (0 < count($bookingData->pickupsOutbound)) {
            $payload['zustiege']['zustieg'] = [];
            foreach ($bookingData->pickupsOutbound as $pickup) {
                $payload['zustiege']['zustieg'][] = [
                    '@idzustieg' => $pickup->id,
                    '@anzahl' => count($pickup->mapping),
                    '@zuordnung' => implode(',', array_map(fn ($index) => $index + 1, $pickup->mapping)),
                ];
            }
        }
    }

    /**
     * Creates a booking request payload for new bookings (inquiry or final booking).
     *
     * Generates the array payload structure for creating new bookings through the BusProNet API.
     * This includes all participant data, room selections, services (including insurance), and
     * payment information. The booking type determines whether this is an inquiry validation
     * ('Anfrage') or a final booking commit ('Buchung').
     *
     * @param BookingCreateDto $bookingDto  The booking creation form data
     * @param string           $bookingType Either 'Anfrage' (inquiry) or 'Buchung' (final booking)
     *
     * @return array The structured payload array for BusProNet API submission
     */
    public function createBookingRequestPayload(BookingCreateDto $bookingDto, string $bookingType): array
    {
        $firstParticipant = $bookingDto->participants[0];

        $payload = [
            'buchungsart' => $bookingType,
            'status' => 'F',
            'idreise' => $bookingDto->travel->id,
            'idpartner' => $bookingDto->travel->hotelId,
            'idagentur' => $bookingDto->agencyId,
        ];

        // Add applicant (first participant data)
        $payload['anmelder'] = [
            'name' => $firstParticipant->lastName,
            'vorname' => $firstParticipant->firstName,
            'geschlecht' => $firstParticipant->gender ?? '',
            'nationalitaet' => $firstParticipant->nationality ?? '',
        ];

        if (null !== $firstParticipant->dateOfBirth) {
            $payload['anmelder']['geburtsdatum'] = $firstParticipant->dateOfBirth->format('d.m.Y');
        }

        // Add address for applicant
        if (null !== $firstParticipant->address) {
            $payload['anmelder']['anschrift'] = $firstParticipant->address->toPayload();
        }

        if (null !== $firstParticipant->email || null !== $firstParticipant->mobile) {
            $payload['anmelder']['kommunikation'] = [];
            if (null !== $firstParticipant->email) {
                $payload['anmelder']['kommunikation']['email'] = $firstParticipant->email;
            }
            if (null !== $firstParticipant->mobile) {
                $payload['anmelder']['kommunikation']['telefonmobil'] = $firstParticipant->mobile;
            }
        }

        // Add participants
        $payload['teilnehmerliste']['teilnehmer'] = [];
        foreach ($bookingDto->participants as $index => $participant) {
            $participantData = [
                '@id' => $index + 1,
                'name' => $participant->lastName,
                'vorname' => $participant->firstName,
                'geschlecht' => $participant->gender ?? '',
                'nationalitaet' => $participant->nationality ?? '',
            ];

            if (null !== $participant->dateOfBirth) {
                $participantData['geburtsdatum'] = $participant->dateOfBirth->format('d.m.Y');
            }

            // Add address (always include structure, even if empty)
            $participantData['anschrift'] = $participant->address?->toPayload() ?? [
                'strasse' => null,
                'plz' => null,
                'ort' => null,
                'ortsteil' => null,
                'land' => null,
            ];

            // Add contact info for all participants
            if (null !== $participant->email || null !== $participant->mobile) {
                $participantData['kommunikation'] = [];
                if (null !== $participant->email) {
                    $participantData['kommunikation']['email'] = $participant->email;
                }
                if (null !== $participant->mobile) {
                    $participantData['kommunikation']['telefonmobil'] = $participant->mobile;
                }
            }

            // Add wishes (room remarks and license plate)
            if (null !== $participant->remarksRoom || null !== $participant->licensePlate) {
                $participantData['wünsche'] = [];
                if (null !== $participant->remarksRoom && '' !== trim($participant->remarksRoom)) {
                    $participantData['wünsche']['unterbringungswunsch'] = $participant->remarksRoom;
                }
                if (null !== $participant->licensePlate && '' !== trim($participant->licensePlate)) {
                    $participantData['wünsche']['beförderungswunsch'] = $participant->licensePlate;
                }
            }

            $payload['teilnehmerliste']['teilnehmer'][] = $participantData;
        }

        // Collect and group all services by ID with participant mappings
        $serviceMap = $this->collectServiceMappings($bookingDto);
        $transportationMap = $this->collectTransportationMappings($bookingDto);
        $roomMap = $this->collectRoomMappings($bookingDto);
        $pickupMap = $this->collectPickupMappings($bookingDto);
        $insuranceMap = $this->collectInsuranceMappings($bookingDto);

        // Add services using reusable helper methods
        $this->addServicesFromMap($payload, 'beförderungen', 'beförderung', '@idleistung', $transportationMap);
        $this->addRoomMappingsToPayload($payload, $roomMap, $bookingDto);
        $this->addServicesFromMap($payload, 'zusatzleistungen', 'zusatzleistung', '@idleistung', $serviceMap);
        $this->addServicesFromMap($payload, 'zustiege', 'zustieg', '@idzustieg', $pickupMap);
        $this->addServicesFromMap($payload, 'versicherungen', 'versicherung', '@idversicherung', $insuranceMap);

        // Add payment information
        $payload['zahlung'] = [
            '@idzahlungsart' => Constants::PAYMENT_METHOD_DEBIT === $bookingDto->paymentMethod
                ? Constants::PAYMENT_TYPE_ID_DEBIT
                : Constants::PAYMENT_TYPE_ID_TRANSFER,
            '@art' => Constants::PAYMENT_METHOD_DEBIT === $bookingDto->paymentMethod ? 'EINZUG' : 'UEBERWEISUNG',
        ];

        if (Constants::PAYMENT_METHOD_DEBIT === $bookingDto->paymentMethod && null !== $bookingDto->bankAccount) {
            $payload['zahlung']['bankverbindung'] = [
                '@iban' => $bookingDto->bankAccount->iban,
                '@kontoinhaber' => $bookingDto->bankAccount->accountHolder,
            ];
        }

        return $payload;
    }

    /**
     * Adds services from a mapping to the payload.
     *
     * Generic helper method that converts service ID => participant IDs mappings
     * into XML payload structure.
     *
     * @param array  $payload         The payload array to modify
     * @param string $sectionKey      The section key (e.g., 'beförderungen', 'versicherungen')
     * @param string $itemKey         The item key (e.g., 'beförderung', 'versicherung')
     * @param string $idAttributeName The ID attribute name (e.g., '@idleistung', '@idversicherung')
     * @param array  $serviceMap      Map of service ID to participant IDs
     */
    private function addServicesFromMap(
        array &$payload,
        string $sectionKey,
        string $itemKey,
        string $idAttributeName,
        array $serviceMap,
    ): void {
        if (false === empty($serviceMap)) {
            $payload[$sectionKey][$itemKey] = [];
            foreach ($serviceMap as $serviceId => $participantIds) {
                $payload[$sectionKey][$itemKey][] = [
                    $idAttributeName => $serviceId,
                    '@anzahl' => count($participantIds),
                    '@zuordnung' => implode(',', $participantIds),
                ];
            }
        }
    }

    /**
     * Adds room mappings with detailed attributes to the payload.
     *
     * Rooms require special attributes beyond simple service mapping:
     * - kategorie (room category code)
     * - idverpflegung (board type ID)
     * - anreise (arrival date)
     * - abreise (departure date)
     * - anzahl (number of rooms of this type booked)
     *
     * @param array            $payload    The payload array to modify
     * @param array            $roomMap    Map of room ID to participant IDs
     * @param BookingCreateDto $bookingDto The booking data for accessing room details and quantities
     */
    private function addRoomMappingsToPayload(array &$payload, array $roomMap, BookingCreateDto $bookingDto): void
    {
        if (empty($roomMap)) {
            return;
        }

        $availableRooms = $bookingDto->travel->getAvailableRooms();
        $payload['ferienzielunterbringungen']['ferienzielunterbringung'] = [];

        // Build room selection quantity lookup
        $roomQuantities = [];
        foreach ($bookingDto->roomSelections as $selection) {
            if ($selection->quantity > 0) {
                $roomQuantities[$selection->roomId] = $selection->quantity;
            }
        }

        foreach ($roomMap as $roomId => $participantIds) {
            $room = $availableRooms[$roomId] ?? null;
            if (null === $room) {
                continue;
            }

            $quantity = $roomQuantities[$roomId] ?? 1;

            $payload['ferienzielunterbringungen']['ferienzielunterbringung'][] = [
                '@idzimmer' => $room->id,
                '@kategorie' => $room->category,
                '@idverpflegung' => $room->boardId,
                '@anreise' => $bookingDto->travel->dateFrom->format('d.m.Y'),
                '@abreise' => $bookingDto->travel->dateTo->format('d.m.Y'),
                '@anzahl' => $quantity,
                '@zuordnung' => implode(',', $participantIds),
            ];
        }
    }

    /**
     * Collects room mappings.
     *
     * Groups participants by their assigned room ID.
     *
     * @return array<string, array<int>> Map of room ID to participant IDs
     */
    private function collectRoomMappings(BookingCreateDto $bookingDto): array
    {
        $roomMap = [];

        foreach ($bookingDto->participants as $index => $participant) {
            $participantId = $index + 1;

            if (null !== $participant->assignedRoomId) {
                $roomMap[$participant->assignedRoomId][] = $participantId;
            }
        }

        return $roomMap;
    }

    /**
     * Collects service mappings for the booking request.
     *
     * Groups board, ski passes, rentals, rental insurance, courses, parking, and additional services
     * by service ID with their participant assignments (1-based).
     *
     * @return array<string, array<int>> Map of service ID to participant IDs
     */
    private function collectServiceMappings(BookingCreateDto $bookingDto): array
    {
        $serviceMap = [];

        foreach ($bookingDto->participants as $index => $participant) {
            $participantId = $index + 1;

            // Board services
            foreach ($participant->board as $board) {
                $serviceMap[$board->id][] = $participantId;
            }

            // Ski pass
            if (null !== $participant->skiPass) {
                $serviceMap[$participant->skiPass->id][] = $participantId;
            }

            // Rentals
            foreach ($participant->rentals as $rental) {
                $serviceMap[$rental->id][] = $participantId;
            }

            // Rental insurance
            if (null !== $participant->rentalInsurance) {
                $serviceMap[$participant->rentalInsurance->id][] = $participantId;
            }

            // Courses
            foreach ($participant->courses as $course) {
                $serviceMap[$course->id][] = $participantId;
            }

            // Parking service (for self-organized transportation)
            if (true === $participant->parking && null !== $participant->parkingService) {
                $serviceMap[$participant->parkingService->id][] = $participantId;
            }

            // Additional services
            foreach ($participant->additionalServices as $service) {
                $serviceMap[$service->id][] = $participantId;
            }
        }

        return $serviceMap;
    }

    /**
     * Collects transportation service mappings.
     *
     * @return array<string, array<int>> Map of transportation service ID to participant IDs
     */
    private function collectTransportationMappings(BookingCreateDto $bookingDto): array
    {
        $transportationMap = [];

        foreach ($bookingDto->participants as $index => $participant) {
            $participantId = $index + 1;

            if (null !== $participant->transportationOutbound) {
                $transportationMap[$participant->transportationOutbound->id][] = $participantId;
            }

            if (null !== $participant->transportationInbound) {
                $transportationMap[$participant->transportationInbound->id][] = $participantId;
            }
        }

        return $transportationMap;
    }

    /**
     * Collects pickup location mappings.
     *
     * Collects the unified pickup selection which applies to both directions.
     * The API receives this as outbound pickup data.
     *
     * @return array<string, array<int>> Map of pickup ID to participant IDs
     */
    private function collectPickupMappings(BookingCreateDto $bookingDto): array
    {
        $pickupMap = [];

        foreach ($bookingDto->participants as $index => $participant) {
            $participantId = $index + 1;

            if (null !== $participant->pickup) {
                $pickupMap[$participant->pickup->id][] = $participantId;
            }
        }

        return $pickupMap;
    }

    /**
     * Collects insurance mappings.
     *
     * CRITICAL: Insurance data is only included in CREATE flow, not in UPDATE flow.
     *
     * @return array<string, array<int>> Map of insurance ID to participant IDs
     */
    private function collectInsuranceMappings(BookingCreateDto $bookingDto): array
    {
        $insuranceMap = [];

        foreach ($bookingDto->participants as $index => $participant) {
            $participantId = $index + 1;

            if (null !== $participant->insurance) {
                $insuranceMap[$participant->insurance->id][] = $participantId;
            }
        }

        return $insuranceMap;
    }
}