class Date

class Date extends NumericDate implements ContainerFactoryPluginInterface {
    use FieldAPIHandlerTrait;
    
    /**
     * The date formatter service.
     *
     * @var \Drupal\Core\Datetime\DateFormatterInterface
     */
    protected $dateFormatter;
    
    /**
     * Date format for SQL conversion.
     *
     * @var string
     *
     * @see \Drupal\views\Plugin\views\query\Sql::getDateFormat()
     */
    protected $dateFormat = DateTimeItemInterface::DATETIME_STORAGE_FORMAT;
    
    /**
     * Determines if the timezone offset is calculated.
     *
     * @var bool
     */
    protected $calculateOffset = TRUE;
    
    /**
     * The request stack used to determine current time.
     *
     * @var \Symfony\Component\HttpFoundation\RequestStack
     */
    protected $requestStack;
    
    /**
     * Constructs a new Date handler.
     *
     * @param array $configuration
     *   A configuration array containing information about the plugin instance.
     * @param string $plugin_id
     *   The plugin ID for the plugin instance.
     * @param mixed $plugin_definition
     *   The plugin implementation definition.
     * @param \Drupal\Core\Datetime\DateFormatterInterface $date_formatter
     *   The date formatter service.
     * @param \Symfony\Component\HttpFoundation\RequestStack $request_stack
     *   The request stack used to determine the current time.
     */
    public function __construct(array $configuration, $plugin_id, $plugin_definition, DateFormatterInterface $date_formatter, RequestStack $request_stack) {
        parent::__construct($configuration, $plugin_id, $plugin_definition);
        $this->dateFormatter = $date_formatter;
        $this->requestStack = $request_stack;
        $definition = $this->getFieldStorageDefinition();
        if ($definition->getSetting('datetime_type') === DateTimeItem::DATETIME_TYPE_DATE) {
            // Date format depends on field storage format.
            $this->dateFormat = DateTimeItemInterface::DATE_STORAGE_FORMAT;
            // Timezone offset calculation is not applicable to dates that are stored
            // as date-only.
            $this->calculateOffset = FALSE;
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
        return new static($configuration, $plugin_id, $plugin_definition, $container->get('date.formatter'), $container->get('request_stack'));
    }
    
    /**
     * Override parent method, which deals with dates as integers.
     */
    protected function opBetween($field) {
        $timezone = $this->getTimezone();
        $origin_offset = $this->getOffset($this->value['min'], $timezone);
        // Although both 'min' and 'max' values are required, default empty 'min'
        // value as UNIX timestamp 0.
        $min = !empty($this->value['min']) ? $this->value['min'] : '@0';
        // Convert to ISO format and format for query. UTC timezone is used since
        // dates are stored in UTC.
        $a = new DateTimePlus($min, new \DateTimeZone($timezone));
        $a = $this->query
            ->getDateFormat($this->query
            ->getDateField("'" . $this->dateFormatter
            ->format($a->getTimestamp() + $origin_offset, 'custom', DateTimeItemInterface::DATETIME_STORAGE_FORMAT, DateTimeItemInterface::STORAGE_TIMEZONE) . "'", TRUE, $this->calculateOffset), $this->dateFormat, TRUE);
        $b = new DateTimePlus($this->value['max'], new \DateTimeZone($timezone));
        $b = $this->query
            ->getDateFormat($this->query
            ->getDateField("'" . $this->dateFormatter
            ->format($b->getTimestamp() + $origin_offset, 'custom', DateTimeItemInterface::DATETIME_STORAGE_FORMAT, DateTimeItemInterface::STORAGE_TIMEZONE) . "'", TRUE, $this->calculateOffset), $this->dateFormat, TRUE);
        // This is safe because we are manually scrubbing the values.
        $operator = strtoupper($this->operator);
        $field = $this->query
            ->getDateFormat($this->query
            ->getDateField($field, TRUE, $this->calculateOffset), $this->dateFormat, TRUE);
        $this->query
            ->addWhereExpression($this->options['group'], "{$field} {$operator} {$a} AND {$b}");
    }
    
    /**
     * Override parent method, which deals with dates as integers.
     */
    protected function opSimple($field) {
        $timezone = $this->getTimezone();
        $origin_offset = $this->getOffset($this->value['value'], $timezone);
        // Convert to ISO. UTC timezone is used since dates are stored in UTC.
        $value = new DateTimePlus($this->value['value'], new \DateTimeZone($timezone));
        $value = $this->query
            ->getDateFormat($this->query
            ->getDateField("'" . $this->dateFormatter
            ->format($value->getTimestamp() + $origin_offset, 'custom', DateTimeItemInterface::DATETIME_STORAGE_FORMAT, DateTimeItemInterface::STORAGE_TIMEZONE) . "'", TRUE, $this->calculateOffset), $this->dateFormat, TRUE);
        // This is safe because we are manually scrubbing the value.
        $field = $this->query
            ->getDateFormat($this->query
            ->getDateField($field, TRUE, $this->calculateOffset), $this->dateFormat, TRUE);
        $this->query
            ->addWhereExpression($this->options['group'], "{$field} {$this->operator} {$value}");
    }
    
    /**
     * Get the proper time zone to use in computations.
     *
     * Date-only fields do not have a time zone associated with them, so the
     * filter input needs to use UTC for reference. Otherwise, use the time zone
     * for the current user.
     *
     * @return string
     *   The time zone name.
     */
    protected function getTimezone() {
        return $this->dateFormat === DateTimeItemInterface::DATE_STORAGE_FORMAT ? DateTimeItemInterface::STORAGE_TIMEZONE : date_default_timezone_get();
    }
    
    /**
     * Get the proper offset from UTC to use in computations.
     *
     * @param string $time
     *   A date/time string compatible with \DateTime. It is used as the
     *   reference for computing the offset, which can vary based on the time
     *   zone rules.
     * @param string $timezone
     *   The time zone that $time is in.
     *
     * @return int
     *   The computed offset in seconds.
     */
    protected function getOffset($time, $timezone) {
        // Date-only fields do not have a time zone or offset from UTC associated
        // with them. For relative (i.e. 'offset') comparisons, we need to compute
        // the user's offset from UTC for use in the query.
        $origin_offset = 0;
        if ($this->dateFormat === DateTimeItemInterface::DATE_STORAGE_FORMAT && $this->value['type'] === 'offset') {
            $origin_offset = $origin_offset + timezone_offset_get(new \DateTimeZone(date_default_timezone_get()), new \DateTime($time, new \DateTimeZone($timezone)));
        }
        return $origin_offset;
    }

}