<?php

namespace Ajaxy\Forms\Inc\Types;

use Isolated\Symfony\Component\Form\Exception\LogicException;
use Isolated\Symfony\Component\Form\Extension\Core\DataTransformer\ArrayToPartsTransformer;
use Isolated\Symfony\Component\Form\Extension\Core\DataTransformer\DataTransformerChain;
use Isolated\Symfony\Component\Form\Extension\Core\DataTransformer\DateTimeImmutableToDateTimeTransformer;
use Isolated\Symfony\Component\Form\Extension\Core\DataTransformer\DateTimeToArrayTransformer;
use Isolated\Symfony\Component\Form\Extension\Core\DataTransformer\DateTimeToHtml5LocalDateTimeTransformer;
use Isolated\Symfony\Component\Form\Extension\Core\DataTransformer\DateTimeToLocalizedStringTransformer;
use Isolated\Symfony\Component\Form\Extension\Core\DataTransformer\DateTimeToStringTransformer;
use Isolated\Symfony\Component\Form\Extension\Core\DataTransformer\DateTimeToTimestampTransformer;
use Isolated\Symfony\Component\Form\Extension\Core\Type\DateTimeType as SymfonyDateTimeType;
use Isolated\Symfony\Component\Form\Extension\Core\Type\DateType;
use Isolated\Symfony\Component\Form\Extension\Core\Type\TimeType;
use Isolated\Symfony\Component\Form\FormBuilderInterface;
use Isolated\Symfony\Component\Form\FormEvent;
use Isolated\Symfony\Component\Form\FormEvents;
use Isolated\Symfony\Component\Form\FormInterface;
use Isolated\Symfony\Component\Form\FormView;
use Isolated\Symfony\Component\Form\ReversedTransformer;
use Isolated\Symfony\Component\OptionsResolver\Exception\InvalidOptionsException;
use Isolated\Symfony\Component\OptionsResolver\Options;
use Isolated\Symfony\Component\OptionsResolver\OptionsResolver;

class DateTimeType extends SymfonyDateTimeType
{
    public const DEFAULT_DATE_FORMAT = \IntlDateFormatter::MEDIUM;
    public const DEFAULT_TIME_FORMAT = \IntlDateFormatter::MEDIUM;

    /**
     * The HTML5 datetime-local format as defined in
     * http://w3c.github.io/html-reference/datatypes.html#form.data.datetime-local.
     */
    public const HTML5_FORMAT = "yyyy-MM-dd'T'HH:mm:ss";

    private const ACCEPTED_FORMATS = [
        \IntlDateFormatter::FULL,
        \IntlDateFormatter::LONG,
        \IntlDateFormatter::MEDIUM,
        \IntlDateFormatter::SHORT,
    ];

    public function buildForm(FormBuilderInterface $builder, array $options): void
    {
        $parts = ['year', 'month', 'day', 'hour'];
        $dateParts = ['year', 'month', 'day'];
        $timeParts = ['hour'];

        if ($options['with_minutes']) {
            $parts[] = 'minute';
            $timeParts[] = 'minute';
        }

        if ($options['with_seconds']) {
            $parts[] = 'second';
            $timeParts[] = 'second';
        }

        $dateFormat = \is_int($options['date_format']) ? $options['date_format'] : self::DEFAULT_DATE_FORMAT;
        $timeFormat = self::DEFAULT_TIME_FORMAT;
        $calendar = \IntlDateFormatter::GREGORIAN;
        $pattern = \is_string($options['format']) ? $options['format'] : null;

        if (!\in_array($dateFormat, self::ACCEPTED_FORMATS, true)) {
            throw new InvalidOptionsException('The "date_format" option must be one of the IntlDateFormatter constants (FULL, LONG, MEDIUM, SHORT) or a string representing a custom format.');
        }

        if ('single_text' === $options['widget']) {
            if (self::HTML5_FORMAT === $pattern) {
                $builder->addViewTransformer(new DateTimeToHtml5LocalDateTimeTransformer(
                    $options['model_timezone'],
                    $options['view_timezone'],
                    $options['with_seconds']
                ));
            } else {
                $builder->addViewTransformer(new DateTimeToLocalizedStringTransformer(
                    $options['model_timezone'],
                    $options['view_timezone'],
                    $dateFormat,
                    $timeFormat,
                    $calendar,
                    $pattern
                ));
            }
        } else {
            // when the form is compound the entries of the array are ignored in favor of children data
            // so we need to handle the cascade setting here
            $emptyData = $builder->getEmptyData() ?: [];
            // Only pass a subset of the options to children
            $dateOptions = array_intersect_key($options, array_flip([
                'years',
                'months',
                'days',
                'placeholder',
                'choice_translation_domain',
                'required',
                'translation_domain',
                'html5',
                'invalid_message',
                'invalid_message_parameters',
            ]));

            if ($emptyData instanceof \Closure) {
                $lazyEmptyData = static fn($option) => static function (FormInterface $form) use ($emptyData, $option) {
                    $emptyData = $emptyData($form->getParent());

                    return $emptyData[$option] ?? '';
                };

                $dateOptions['empty_data'] = $lazyEmptyData('date');
            } elseif (isset($emptyData['date'])) {
                $dateOptions['empty_data'] = $emptyData['date'];
            }

            $timeOptions = array_intersect_key($options, array_flip([
                'hours',
                'minutes',
                'seconds',
                'with_minutes',
                'with_seconds',
                'placeholder',
                'choice_translation_domain',
                'required',
                'translation_domain',
                'html5',
                'invalid_message',
                'invalid_message_parameters',
            ]));

            if ($emptyData instanceof \Closure) {
                $timeOptions['empty_data'] = $lazyEmptyData('time');
            } elseif (isset($emptyData['time'])) {
                $timeOptions['empty_data'] = $emptyData['time'];
            }

            if (false === $options['label']) {
                $dateOptions['label'] = false;
                $timeOptions['label'] = false;
            }

            $dateOptions['widget'] = $options['date_widget'] ?? $options['widget'] ?? 'choice';
            $timeOptions['widget'] = $options['time_widget'] ?? $options['widget'] ?? 'choice';

            if (null !== $options['date_label']) {
                $dateOptions['label'] = $options['date_label'];
            }

            if (null !== $options['time_label']) {
                $timeOptions['label'] = $options['time_label'];
            }

            if (null !== $options['date_format']) {
                $dateOptions['format'] = $options['date_format'];
            }

            $dateOptions['input'] = $timeOptions['input'] = 'array';
            $dateOptions['error_bubbling'] = $timeOptions['error_bubbling'] = true;

            $builder
                // ->addViewTransformer(new DataTransformerChain([
                //     new DateTimeToArrayTransformer($options['model_timezone'], $options['view_timezone'], $parts),
                //     new ArrayToPartsTransformer([
                //         'date' => $dateParts,
                //         'time' => $timeParts,
                //     ]),

                // ]))
                ->add('date', DateType::class, $dateOptions)
                ->add('time', TimeType::class, $timeOptions)
            ;
        }

        if ('datetime_immutable' === $options['input']) {
            $builder->addModelTransformer(new DateTimeImmutableToDateTimeTransformer());
        } elseif ('string' === $options['input']) {
            $builder->addModelTransformer(new ReversedTransformer(
                new DateTimeToStringTransformer($options['model_timezone'], $options['model_timezone'], $options['input_format'])
            ));
        } elseif ('timestamp' === $options['input']) {
            $builder->addModelTransformer(new ReversedTransformer(
                new DateTimeToTimestampTransformer($options['model_timezone'], $options['model_timezone'])
            ));
        } elseif ('array' === $options['input']) {
            // $builder->addModelTransformer(new DataTransformerChain([
            //     new ReversedTransformer(
            //         new ArrayToPartsTransformer([
            //             'date' => $dateParts,
            //             'time' => $timeParts,
            //         ])
            //     ),
            //     new ReversedTransformer(
            //         new DateTimeToArrayTransformer($options['model_timezone'], $options['model_timezone'], $parts)
            //     )
            // ]));
        }

        if (\in_array($options['input'], ['datetime', 'datetime_immutable'], true) && null !== $options['model_timezone']) {
            $builder->addEventListener(FormEvents::POST_SET_DATA, static function (FormEvent $event) use ($options): void {
                $date = $event->getData();

                if (!$date instanceof \DateTimeInterface) {
                    return;
                }

                if ($date->getTimezone()->getName() !== $options['model_timezone']) {
                    throw new LogicException(\esc_html(sprintf('Using a "%s" instance with a timezone ("%s") not matching the configured model timezone "%s" is not supported.', get_debug_type($date), $date->getTimezone()->getName(), $options['model_timezone'])));
                }
            });
        }
    }

    public function buildView(FormView $view, FormInterface $form, array $options): void
    {
        $view->vars['widget'] = $options['widget'];

        // Change the input to an HTML5 datetime input if
        //  * the widget is set to "single_text"
        //  * the format matches the one expected by HTML5
        //  * the html5 is set to true
        if ($options['html5'] && 'single_text' === $options['widget'] && self::HTML5_FORMAT === $options['format']) {
            $view->vars['type'] = 'datetime-local';

            // we need to force the browser to display the seconds by
            // adding the HTML attribute step if not already defined.
            // Otherwise the browser will not display and so not send the seconds
            // therefore the value will always be considered as invalid.
            if (!isset($view->vars['attr']['step'])) {
                if ($options['with_seconds']) {
                    $view->vars['attr']['step'] = 1;
                } elseif (!$options['with_minutes']) {
                    $view->vars['attr']['step'] = 3600;
                }
            }
        }
    }

    public function configureOptions(OptionsResolver $resolver): void
    {
        $compound = static fn(Options $options) => 'single_text' !== $options['widget'];

        $resolver->setDefaults([
            'input' => 'datetime',
            'model_timezone' => null,
            'view_timezone' => null,
            'format' => self::HTML5_FORMAT,
            'date_format' => null,
            'widget' => null,
            'date_widget' => null,
            'time_widget' => null,
            'with_minutes' => true,
            'with_seconds' => false,
            'html5' => true,
            // Don't modify \DateTime classes by reference, we treat
            // them like immutable value objects
            'by_reference' => false,
            'error_bubbling' => false,
            // If initialized with a \DateTime object, FormType initializes
            // this option to "\DateTime". Since the internal, normalized
            // representation is not \DateTime, but an array, we need to unset
            // this option.
            'data_class' => null,
            'compound' => $compound,
            'date_label' => null,
            'time_label' => null,
            'empty_data' => static fn(Options $options) => $options['compound'] ? [] : '',
            'input_format' => 'Y-m-d H:i:s',
            'invalid_message' => 'Please enter a valid date and time.',
        ]);

        // Don't add some defaults in order to preserve the defaults
        // set in DateType and TimeType
        $resolver->setDefined([
            'placeholder',
            'choice_translation_domain',
            'years',
            'months',
            'days',
            'hours',
            'minutes',
            'seconds',
        ]);

        $resolver->setAllowedValues('input', [
            'datetime',
            'datetime_immutable',
            'string',
            'timestamp',
            'array',
        ]);
        $resolver->setAllowedValues('date_widget', [
            null, // inherit default from DateType
            'single_text',
            'text',
            'choice',
        ]);
        $resolver->setAllowedValues('time_widget', [
            null, // inherit default from TimeType
            'single_text',
            'text',
            'choice',
        ]);
        // This option will overwrite "date_widget" and "time_widget" options
        $resolver->setAllowedValues('widget', [
            null, // default, don't overwrite options
            'single_text',
            'text',
            'choice',
        ]);

        $resolver->setAllowedTypes('input_format', 'string');

        $resolver->setNormalizer('date_format', static function (Options $options, $dateFormat) {
            if (null !== $dateFormat && 'single_text' === $options['widget'] && self::HTML5_FORMAT === $options['format']) {
                throw new LogicException(sprintf('Cannot use the "date_format" option of the "%s" with an HTML5 date.', self::class));
            }

            return $dateFormat;
        });
        $resolver->setNormalizer('widget', static function (Options $options, $widget) {
            if ('single_text' === $widget) {
                if (null !== $options['date_widget']) {
                    throw new LogicException(sprintf('Cannot use the "date_widget" option of the "%s" when the "widget" option is set to "single_text".', self::class));
                }
                if (null !== $options['time_widget']) {
                    throw new LogicException(sprintf('Cannot use the "time_widget" option of the "%s" when the "widget" option is set to "single_text".', self::class));
                }
            } elseif (null === $widget && null === $options['date_widget'] && null === $options['time_widget']) {
                return 'single_text';
            }

            return $widget;
        });
        $resolver->setNormalizer('html5', static function (Options $options, $html5) {
            if ($html5 && self::HTML5_FORMAT !== $options['format']) {
                throw new LogicException(sprintf('Cannot use the "format" option of "%s" when the "html5" option is enabled.', self::class));
            }

            return $html5;
        });
    }

    public function getBlockPrefix(): string
    {
        return 'datetime';
    }
}