class Apartment::Elevators::Subdomain

def self.excluded_subdomains
  @excluded_subdomains ||= []
end

def self.excluded_subdomains=(arg)
  @excluded_subdomains = arg
end

def domain_valid?(host)
  PublicSuffix.valid?(host, ignore_private: true)
end

def host_valid?(host)
  !ip_host?(host) && domain_valid?(host)
end

def ip_host?(host)
  !/^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$/.match(host).nil?
end

def parse_host(host)
  (PublicSuffix.parse(host, ignore_private: true).trd || '').split('.')
end

def parse_tenant_name(request)
  request_subdomain = subdomain(request.host)
  # If the domain acquired is set to be excluded, set the tenant to whatever is currently
  # next in line in the schema search path.
  tenant = if self.class.excluded_subdomains.include?(request_subdomain)
             nil
           else
             request_subdomain
           end
  tenant.presence
end

def subdomain(host)
  subdomains(host).first
end

def subdomains(host)
  host_valid?(host) ? parse_host(host) : []
end