<?php

declare(strict_types=1);

namespace App\Service;

use App\Form\Model\BookingDto;

/**
 * Generates fingerprints of booking state for change detection in edit mode.
 *
 * Creates SHA-256 hashes of all mutable booking data to detect unsaved changes.
 * Used by EditController to determine if user modifications need to be saved.
 */
class BookingFingerprintService
{
    /**
     * Generates a fingerprint (hash) of all mutable booking data.
     *
     * The fingerprint includes payment details and all participant data including
     * personal information, addresses, body dimensions, room assignments, and service selections.
     */
    public function generateFingerprint(BookingDto $bookingDto, bool $logData = false): string
    {
        $data = [
            'paymentMethod' => $bookingDto->paymentMethod,
            'bankAccount' => [
                'iban' => $bookingDto->bankAccount?->iban,
                'accountHolder' => $bookingDto->bankAccount?->accountHolder,
            ],
            'participants' => [],
        ];

        foreach ($bookingDto->participants as $index => $participant) {
            $data['participants'][$index] = [
                'personalData' => [
                    'firstName' => $participant->firstName,
                    'lastName' => $participant->lastName,
                    'dateOfBirth' => $participant->dateOfBirth?->format('Y-m-d'),
                    'email' => $participant->email,
                    'mobile' => $participant->mobile,
                    'gender' => $participant->gender,
                    'nationality' => $participant->nationality,
                ],
                'address' => [
                    'street' => $participant->address?->street,
                    'postCode' => $participant->address?->postCode,
                    'city' => $participant->address?->city,
                    'country' => $participant->address?->country,
                ],
                'bodyDimensions' => [
                    'height' => $participant->height,
                    'weight' => $participant->weight,
                    'shoeSize' => $participant->shoeSize,
                ],
                'roomAssignment' => [
                    'assignedRoomId' => $participant->assignedRoomId,
                    'remarksRoom' => $participant->remarksRoom,
                ],
                'licensePlate' => $participant->licensePlate,
                'services' => [
                    'skiPass' => $participant->skiPass?->id,
                    'courses' => $this->normalizeServiceArray($participant->courses),
                    'board' => $this->normalizeServiceArray($participant->board),
                    'rentals' => $this->normalizeServiceArray($participant->rentals),
                    'rentalInsurance' => $participant->rentalInsurance?->id,
                    'additionalServices' => $this->normalizeServiceArray($participant->additionalServices),
                    'transportationOutbound' => $participant->transportationOutbound?->id,
                    'transportationInbound' => $participant->transportationInbound?->id,
                    'pickup' => $participant->pickup?->id,
                    'parking' => $participant->parking,
                    'insurance' => $participant->insurance?->id,
                    'bulkInsuranceBooking' => $participant->bulkInsuranceBooking,
                ],
            ];
        }

        $fingerprint = hash('sha256', serialize($data));

        if ($logData) {
            error_log(sprintf('[Fingerprint] Generated fingerprint: %s', $fingerprint));
            error_log(sprintf('[Fingerprint] Serialized data: %s', serialize($data)));
        }

        return $fingerprint;
    }

    /**
     * Normalizes a service array to ensure consistent fingerprinting.
     *
     * Extracts service IDs, sorts them, and returns a simple indexed array.
     * This ensures that associative arrays, indexed arrays, and different orders
     * all produce the same fingerprint as long as the same services are present.
     *
     * @param array $services Array of Service objects
     *
     * @return array Sorted array of service IDs
     */
    private function normalizeServiceArray(array $services): array
    {
        $ids = array_map(fn ($s) => $s->id, $services);
        sort($ids);

        return array_values($ids);
    }

    /**
     * Checks if the booking has unsaved changes in edit mode.
     *
     * Compares the current state fingerprint with the original fingerprint
     * that was set when the booking was loaded from the API.
     */
    public function isDirty(BookingDto $bookingDto): bool
    {
        if (BookingDto::MODE_EDIT !== $bookingDto->getMode()) {
            return false;
        }

        if (null === $bookingDto->originalFingerprint) {
            return false;
        }

        $currentFingerprint = $this->generateFingerprint($bookingDto);
        $isDirty = $bookingDto->originalFingerprint !== $currentFingerprint;

        // Debug logging to identify what changed
        if ($isDirty) {
            error_log(sprintf('[Fingerprint] DIRTY DETECTED! Original: %s, Current: %s', $bookingDto->originalFingerprint, $currentFingerprint));
            $this->logFingerprintDiff($bookingDto);
        }

        return $isDirty;
    }

    /**
     * Logs detailed fingerprint data for debugging dirty state issues.
     */
    private function logFingerprintDiff(BookingDto $bookingDto): void
    {
        foreach ($bookingDto->participants as $index => $participant) {
            $participantData = [
                'firstName' => $participant->firstName,
                'lastName' => $participant->lastName,
                'dateOfBirth' => $participant->dateOfBirth?->format('Y-m-d'),
                'email' => $participant->email,
                'mobile' => $participant->mobile,
                'gender' => $participant->gender,
                'nationality' => $participant->nationality,
                'address' => [
                    'street' => $participant->address?->street,
                    'postCode' => $participant->address?->postCode,
                    'city' => $participant->address?->city,
                    'country' => $participant->address?->country,
                ],
                'services' => [
                    'skiPass' => $participant->skiPass?->id,
                    'courses' => $this->normalizeServiceArray($participant->courses),
                    'board' => $this->normalizeServiceArray($participant->board),
                    'rentals' => $this->normalizeServiceArray($participant->rentals),
                    'rentalInsurance' => $participant->rentalInsurance?->id,
                    'additionalServices' => $this->normalizeServiceArray($participant->additionalServices),
                    'transportationOutbound' => $participant->transportationOutbound?->id,
                    'transportationInbound' => $participant->transportationInbound?->id,
                    'pickup' => $participant->pickup?->id,
                    'parking' => $participant->parking,
                ],
            ];

            error_log(sprintf('[Fingerprint] Participant %d data: %s', $index, json_encode($participantData)));
        }
    }
}