class Fastly::Invoice

def self.delete_path
  fail "You can't DELETE to an invoice"
end

def self.get_path(*args)
  opts = args.size > 0 ? args[0] : {}
  url  = '/billing/v2'
  url += if opts.key?(:year) && opts.key?(:month)
           "/year/#{opts[:year]}/month/#{opts[:month]}"
         elsif opts.key?(:id)
           "/account_customers/#{opts[:customer_id]}/invoices/#{opts[:id]}"
         elsif opts.key?(:mtd)
           "/account_customers/#{opts[:customer_id]}/mtd_invoice"
         else
           "/account_customers/#{opts[:customer_id]}/invoices"
         end
  url
end

def self.list_path(*args)
  get_path(*args)
end

def self.post_path
  fail "You can't POST to an invoice"
end

def self.put_path
  fail "You can't PUT to an invoice"
end

def delete!
  fail "You can't delete an invoice"
end

def end
  DateTime.parse(end_time).new_offset(0)
end

def save!
  fail "You can't save an invoice"
end

def start
  DateTime.parse(start_time).new_offset(0)
end