<?php

namespace App\Yr\Forecast\Tabular\Time;

abstract class AbstractUnit implements DiffInterface {
    const DEFAULT_VARIANCE = 2;

    private $value;
    private $unit;

    public function __construct(float $value, string $unit) {
        $this->value = $value;
        $this->unit = $unit;
    }

    public function getValue(): float {
        return $this->value;
    }

    public function getUnit(): string {
        return $this->unit;
    }

    public function setThresholdValue(int $t): self {
        $this->threshold = $t;
    }

    public function diff(DiffInterface $d): bool {
        if ($d instanceof $this)
            return abs($this->value - $d->getValue()) > static::DEFAULT_VARIANCE;

        return false;
    }

    public function __toString(): string {
        return sprintf(
            "%s: %f %s", basename(str_replace(
                '\\', DIRECTORY_SEPARATOR, get_class($this)
            )), $this->value, $this->unit);
    }
}