defmodule AlchemyTable.Table.Utils do
  alias Bigtable.MutateRow

  def atoms_from_dots(string) do
    string
    |> String.replace(~r/[\[\]]/, "")
    |> String.split(".")
    |> Enum.map(&String.to_atom/1)
  end

  def build_key_parts(key_pattern) do
    key_pattern
    |> String.split("#")
    |> Enum.map(fn string ->
      case Regex.run(~r/\[(.*)\]/, string) do
        [h | _] ->
          atoms_from_dots(h)

        nil ->
          string
      end
    end)
  end

  def build_row_key(key_parts, data) do
    key_parts
    |> Enum.map(fn kp ->
      if is_list(kp) do
        get_in(data, kp)
      else
        kp
      end
    end)
    |> Enum.join("#")
  end

  def add_ts(key, opts, timestamp) do
    ts_suffix =
      if Keyword.get(opts, :ts, false) do
        "##{timestamp}"
      else
        ""
      end

    key <> ts_suffix
  end

  def get_key_pattern!(opts) do
    Keyword.fetch!(opts, :row_key)
  end

  def get_key_pattern(opts) do
    Keyword.get(opts, :row_key)
  end

  def clone_update(main_key, main_update, data, opts, timestamp) do
    key =
      case get_key_pattern(opts) do
        nil ->
          main_key

        key ->
          key
          |> build_key_parts()
          |> build_row_key(data)
      end

    key = key |> add_ts(opts, timestamp)

    %{main_update | row_key: key}
  end

  def build_mutate_row({instance, table, mutations}) do
    table_name = to_string(table) |> Recase.to_kebab()

    mutations
    |> MutateRow.build("#{instance}/tables/#{table_name}")
  end
end