defmodule WandererApp.Utils.CSVUtil do
  @moduledoc false

  alias NimbleCSV.RFC4180, as: CSV

  def get_column_names(file) do
    file
    |> File.stream!()
    |> CSV.parse_stream(skip_headers: false)
    |> Enum.fetch!(0)
    |> Enum.with_index()
    |> Map.new(fn {val, num} -> {num, val} end)
  end

  def csv_row_to_table_record(file, mapper) do
    column_names = get_column_names(file)

    file
    |> File.stream!()
    |> CSV.parse_stream(skip_headers: true)
    |> Enum.map(fn row ->
      row
      |> Enum.with_index()
      |> Map.new(fn {val, num} -> {column_names[num], val} end)
      |> mapper.()
    end)
  end
end