public function CostIsDeductible(Cost $value)
{
$enoughMetal = $this->Metal() - $value->Metal() >= 0;
$enoughCrystal = $this->Crystal() - $value->Crystal() >= 0;
$enoughDeuterium = $this->Deuterium() - $value->Deuterium() >= 0;
$enoughEnergy = $this->Energy() - $value->Energy() >= 0;
if ($enoughMetal && $enoughCrystal && $enoughDeuterium && $enoughEnergy) {
return true;
}
return false;
}