Generate map pattern matching functions

I have a goal to code generate the following module

defmodule C do 
  def first(%{company_id: company_id}, user}, do: do_first(company_id, user)
  def first(%{sales_id: sales_id}, user}, do: do_first(sales_id, user)
  #... etc
end

I’d like to create a macro potentially? Or even a function where I can give it a list of those atoms, and have it delegate those arguments to the second function
i.e

defmodule C do
  use FirstMacro, [:company_id, :sales_id]  #... could be a very long list
end

I keep writing macros but am unable to figure out how to code pattern match on a map macro the quoted ast for a map is something like {:%{}, , [key: value]} but I’m not able grab value like I would in defining a function so I can’t achieve my goal here, can someone point me in the right direction kindly ^^. Thanks for any help!

my attempt on the 100th iteration looks something like this

defmodule C do
  defmacro first_list(list, user) do
    quote bind_quoted: [list: list, user: user] do
      Enum.map(list, fn x ->
        def first(unquote({:%{}, [], []}), user),
          do: do_first(:need_this_variable, user)
      end)
    end
  end
end

But I know its all wrong