<?php

declare(strict_types=1);

namespace App\Form\Service;

use App\BusProNet\Constants;
use App\BusProNet\Model\Service;
use App\Form\Model\BookingDto;
use App\Form\Service\Abstract\AbstractParticipantFieldHandler;

/**
 * Handles processing of the rentals field for booking participants.
 *
 * This handler manages rental equipment selections for participants in the booking
 * creation process. It processes the rentals field from form submissions,
 * filters out age-inappropriate options and duration-inappropriate options, and
 * updates the participant DTO with only valid selections.
 *
 * Dependencies: dateOfBirth (for age evaluation) and skiPass (for duration filtering)
 */
class ParticipantRentalsFieldHandler extends AbstractParticipantFieldHandler
{
    public function getFieldName(): string
    {
        return 'rentals';
    }

    /**
     * Returns the field dependencies for proper processing order.
     *
     * This handler depends on both dateOfBirth (for age evaluation) and skiPass
     * (for duration filtering and field visibility logic).
     *
     * @return string[] Array containing 'dateOfBirth' and 'skiPass' dependencies
     */
    public function getDependencies(): array
    {
        return ['dateOfBirth', 'skiPass'];
    }

    /**
     * Determines if this handler should process the field based on submitted data.
     *
     * For service selection fields like rentals, we always need to process
     * to handle cases where all selections are cleared (field not present in data).
     * This ensures the participant DTO is updated with an empty array when no
     * services are selected.
     *
     * @param array<string, mixed> $submittedData    The submitted participant form data
     * @param string               $mode             The booking mode (BookingDto::MODE_CREATE or MODE_EDIT)
     * @param int                  $participantIndex The index of the participant being processed
     *
     * @return bool Always returns true for service selection fields
     */
    public function shouldProcess(array $submittedData, string $mode, int $participantIndex): bool
    {
        return true; // Always process to handle deselection cases
    }

    public function processField(array $submittedData, BookingDto $bookingDto, int $participantIndex): void
    {
        $participant = $this->getParticipant($bookingDto, $participantIndex);
        if (null === $participant) {
            return;
        }

        // Store previous rental state BEFORE checking skipass
        $previousRentals = $participant->rentals;

        // Check if rentals should be available based on skipass selection
        if (null === $participant->skiPass) {
            // No skipass selected = clear all rental selections
            if ([] !== $previousRentals) {
                $participant->addNotification(
                    'warning',
                    'Ausrüstung wurde entfernt (kein Skipass ausgewählt)'
                );
            }
            $participant->rentals = [];

            return;
        }

        $selectedRentals = $this->getFieldValue($submittedData, $this->getFieldName()) ?? [];

        // Get available rentals from travel data (includes booked rentals in edit mode)
        $availableRentals = $this->getAvailableServicesWithBooked(
            $bookingDto,
            $participantIndex,
            Constants::TOKEN_RENTALS,
            true
        );

        // Filter rentals by skipass duration to ensure only matching rentals are available
        $durationFilteredRentals = $this->filterRentalsBySkiPassDuration($availableRentals, $participant);

        $validSelections = $this->filterValidServiceSelections(
            $selectedRentals,
            $durationFilteredRentals,
            $bookingDto,
            $participantIndex
        );

        // Notify if rentals were cleared due to skipass duration change
        // Only show notification if user had submitted rentals that got filtered out,
        // not if the user intentionally cleared the selection (empty submission)
        if ([] !== $previousRentals && [] === $validSelections && [] !== $selectedRentals) {
            $participant->addNotification(
                'warning',
                'Ausrüstung wurde entfernt (andere Skipass-Dauer ausgewählt)'
            );
        }

        $participant->rentals = $validSelections;
    }

    private function filterValidServiceSelections(
        array $selectedServices,
        array $availableServices,
        BookingDto $bookingDto,
        int $participantIndex,
    ): array {
        $validSelections = [];

        foreach ($selectedServices as $selectedService) {
            if ($this->isServiceValidForParticipant($selectedService, $availableServices, $bookingDto, $participantIndex)) {
                // Convert the selected service ID/data back to the actual Service object
                $serviceObject = $this->findServiceInAvailableServices($selectedService, $availableServices);
                if (null !== $serviceObject) {
                    $validSelections[] = $serviceObject;
                }
            }
        }

        return $validSelections;
    }

    private function isServiceValidForParticipant(
        mixed $selectedService,
        array $availableServices,
        BookingDto $bookingDto,
        int $participantIndex,
    ): bool {
        $service = $this->findServiceInAvailableServices($selectedService, $availableServices);

        if (null === $service) {
            return false;
        }

        $ageEvaluator = new ServiceAgeEvaluator();
        if (!$ageEvaluator->canEvaluate($service)) {
            return true;
        }

        return $ageEvaluator->isServiceAvailableForParticipant($service, $bookingDto, $participantIndex);
    }

    /**
     * Filters rentals to only include those matching the skipass duration.
     *
     * Rentals must have exact date matching with the selected skipass:
     * - rental.dateFrom === skipass.dateFrom
     * - rental.dateTo === skipass.dateTo
     *
     * @param array                          $rentals     All available rental services
     * @param \App\Form\Model\ParticipantDto $participant The participant with skipass selection
     *
     * @return array Filtered rentals matching the skipass duration
     */
    private function filterRentalsBySkiPassDuration(array $rentals, $participant): array
    {
        $selectedSkiPass = $participant->skiPass;

        // If skipass has no valid dates, return empty rentals
        if (null === $selectedSkiPass->dateFrom || null === $selectedSkiPass->dateTo) {
            return [];
        }

        return array_filter($rentals, function (Service $rental) use ($selectedSkiPass) {
            // Rental must have valid dates to be considered
            if (null === $rental->dateFrom || null === $rental->dateTo) {
                return false;
            }

            // Exact date matching: rental dates must match skipass dates exactly
            return $rental->dateFrom == $selectedSkiPass->dateFrom
                && $rental->dateTo == $selectedSkiPass->dateTo;
        });
    }
}