<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\Form\Extension\Core\DataTransformer;

use Symfony\Component\Form\Exception\TransformationFailedException;

/**
 * Transforms between a normalized time and a localized time string/array.
 *
 * @author Bernhard Schussek <bschussek@gmail.com>
 * @author Florian Eckerstorfer <florian@eckerstorfer.org>
 *
 * @extends BaseDateTimeTransformer<array>
 */
class DateTimeToArrayTransformer extends BaseDateTimeTransformer
{
    private array $fields;
    private \DateTimeInterface $referenceDate;

    /**
     * @param string|null   $inputTimezone  The input timezone
     * @param string|null   $outputTimezone The output timezone
     * @param string[]|null $fields         The date fields
     * @param bool          $pad            Whether to use padding
     */
    public function __construct(
        ?string $inputTimezone = null,
        ?string $outputTimezone = null,
        ?array $fields = null,
        private bool $pad = false,
        ?\DateTimeInterface $referenceDate = null,
    ) {
        parent::__construct($inputTimezone, $outputTimezone);

        $this->fields = $fields ?? ['year', 'month', 'day', 'hour', 'minute', 'second'];
        $this->referenceDate = $referenceDate ?? new \DateTimeImmutable('1970-01-01 00:00:00');
    }

    public function transform(mixed $dateTime): array
    {
        if (null === $dateTime) {
            return array_intersect_key([
                'year' => '',
                'month' => '',
                'day' => '',
                'hour' => '',
                'minute' => '',
                'second' => '',
            ], array_flip($this->fields));
        }

        if (!$dateTime instanceof \DateTimeInterface) {
            throw new TransformationFailedException('Expected a \DateTimeInterface.');
        }

        if ($this->inputTimezone !== $this->outputTimezone) {
            $dateTime = \DateTimeImmutable::createFromInterface($dateTime);
            $dateTime = $dateTime->setTimezone(new \DateTimeZone($this->outputTimezone));
        }

        $result = array_intersect_key([
            'year' => $dateTime->format('Y'),
            'month' => $dateTime->format('m'),
            'day' => $dateTime->format('d'),
            'hour' => $dateTime->format('H'),
            'minute' => $dateTime->format('i'),
            'second' => $dateTime->format('s'),
        ], array_flip($this->fields));

        if (!$this->pad) {
            foreach ($result as &$entry) {
                // remove leading zeros
                $entry = (string) (int) $entry;
            }
            // unset reference to keep scope clear
            unset($entry);
        }

        return $result;
    }

    public function reverseTransform(mixed $value): ?\DateTime
    {
        if (null === $value) {
            return null;
        }

        if (!\is_array($value)) {
            throw new TransformationFailedException('Expected an array.');
        }

        if ('' === implode('', $value)) {
            return null;
        }

        $emptyFields = [];

        foreach ($this->fields as $field) {
            if (!isset($value[$field])) {
                $emptyFields[] = $field;
            }
        }

        if (\count($emptyFields) > 0) {
            throw new TransformationFailedException(\sprintf('The fields "%s" should not be empty.', implode('", "', $emptyFields)));
        }

        if (isset($value['month']) && !ctype_digit((string) $value['month'])) {
            throw new TransformationFailedException('This month is invalid.');
        }

        if (isset($value['day']) && !ctype_digit((string) $value['day'])) {
            throw new TransformationFailedException('This day is invalid.');
        }

        if (isset($value['year']) && !ctype_digit((string) $value['year'])) {
            throw new TransformationFailedException('This year is invalid.');
        }

        if (!empty($value['month']) && !empty($value['day']) && !empty($value['year']) && false === checkdate($value['month'], $value['day'], $value['year'])) {
            throw new TransformationFailedException('This is an invalid date.');
        }

        if (isset($value['hour']) && !ctype_digit((string) $value['hour'])) {
            throw new TransformationFailedException('This hour is invalid.');
        }

        if (isset($value['minute']) && !ctype_digit((string) $value['minute'])) {
            throw new TransformationFailedException('This minute is invalid.');
        }

        if (isset($value['second']) && !ctype_digit((string) $value['second'])) {
            throw new TransformationFailedException('This second is invalid.');
        }

        try {
            $dateTime = new \DateTime(\sprintf(
                '%s-%s-%s %s:%s:%s',
                empty($value['year']) ? $this->referenceDate->format('Y') : $value['year'],
                empty($value['month']) ? $this->referenceDate->format('m') : $value['month'],
                empty($value['day']) ? $this->referenceDate->format('d') : $value['day'],
                $value['hour'] ?? $this->referenceDate->format('H'),
                $value['minute'] ?? $this->referenceDate->format('i'),
                $value['second'] ?? $this->referenceDate->format('s')
            ),
                new \DateTimeZone($this->outputTimezone)
            );

            if ($this->inputTimezone !== $this->outputTimezone) {
                $dateTime->setTimezone(new \DateTimeZone($this->inputTimezone));
            }
        } catch (\Exception $e) {
            throw new TransformationFailedException($e->getMessage(), $e->getCode(), $e);
        }

        return $dateTime;
    }
}