public function FullfillsPrerequisites(Colony $c) { if ($this->Prerequisite() == NULL) { return true; } foreach ($this->Prerequisite() as $prerequisite) { $prereqName = $prerequisite->Item()->Name(); $prereqAmount = $prerequisite->Amount(); $colonyAmount = $c->SearchForPrerequisite($prereqName)->Amount(); if ($prereqAmount > $colonyAmount) { return false; } } return true; }