<?php

namespace App\Yr\Forecast\Tabular\Time;

/**
 * Wind direction
 *
 * @author Joachim M. Giæver (joachim[]giaever.org)
 */
class WindDirection extends AbstractUnit{
    const DEFAULT_VARIANCE = 22.5;
    private $name;

    /**
     * @param \SimpleXMLElement $xml XML element containing the wind direction
     */
    public function __construct(\SimpleXMLElement $xml) {
        parent::__construct(
            (float)$xml['deg'],
            (string)$xml['code']
        );

        $this->name = (string)$xml['name'];
    }

    /**
     * Returns the wind direction in full,
     * e.g «Northeast».
     *
     * @return string
     */
    public function getName(): string {
        return $this->name;
    }

    /**
     * {@inheritDoc}
     */
    public function diff(DiffInterface $d): int {
        if ($diff = parent::diff($d))
            return $diff > static::DEFAULT_VARIANCE ? 1 : 0;
        return 0;
    }

}