<?php

declare(strict_types=1);

namespace App\Form\Service;

use App\Form\Model\BookingDtoInterface;
use App\Form\Service\Abstract\AbstractParticipantFieldHandler;

/**
 * Handles processing of the assignedRoomId field for booking participants.
 *
 * This handler manages room assignments for participants in the booking creation
 * process. It processes the assignedRoomId field from form submissions and updates
 * the participant DTO with the selected room. The handler properly handles empty
 * selections (converting them to null) and validates numeric room IDs.
 *
 * Field Processing:
 * - Extracts room ID from submitted form data
 * - Converts empty strings to null (unselected choice)
 * - Normalizes string values to integers
 * - Updates the participant's assignedRoomId property
 *
 * Dependencies: None (this is a base field that other handlers may depend on)
 */
class ParticipantAssignedRoomFieldHandler extends AbstractParticipantFieldHandler
{
    /**
     * Returns the form field name this handler processes.
     *
     * This handler is responsible for the 'assignedRoomId' field, which contains
     * the selected room ID for each participant in the booking form.
     *
     * @return string The field name 'assignedRoomId'
     */
    public function getFieldName(): string
    {
        return 'assignedRoomId';
    }

    /**
     * Processes the assignedRoomId field for a specific participant.
     *
     * This method extracts the room assignment from the submitted form data and
     * updates the corresponding participant in the booking DTO. It handles the
     * common form processing pattern where empty selections are submitted as
     * empty strings but should be stored as null values.
     *
     * Processing steps:
     * 1. Safely retrieves the participant object from the DTO
     * 2. Extracts the assignedRoomId value from submitted data
     * 3. Normalizes the value (empty string → null, numeric string → integer)
     * 4. Updates the participant's assignedRoomId property
     *
     * @param array<string, mixed> $submittedData    The submitted participant form data
     * @param BookingDtoInterface  $bookingDto       The booking DTO to update (create or edit)
     * @param int                  $participantIndex The index of the participant being processed
     */
    public function processField(array $submittedData, BookingDtoInterface $bookingDto, int $participantIndex): void
    {
        // Safely get the participant object, returning early if not found
        $participant = $this->getParticipant($bookingDto, $participantIndex);

        if (null === $participant) {
            return;
        }

        // Extract the room ID from form data (defaults to null if not present)
        $roomId = $this->getFieldValue($submittedData, $this->getFieldName());

        // Convert form string to integer, handling empty selections as null
        $participant->assignedRoomId = $this->normalizeIntValue($roomId);
    }
}