defmodule Elixlsx.Compiler.CellStyleDB do
  alias Elixlsx.Compiler.CellStyleDB
  alias Elixlsx.Compiler.FontDB
  alias Elixlsx.Compiler.FillDB
  alias Elixlsx.Compiler.NumFmtDB
  alias Elixlsx.Compiler.BorderStyleDB
  alias Elixlsx.Compiler.WorkbookCompInfo
  alias Elixlsx.Compiler.DBUtil

  defstruct cellstyles: %{}, element_count: 0

  @type t :: %CellStyleDB{
          cellstyles: %{Elixlsx.Style.CellStyle.t() => non_neg_integer},
          element_count: non_neg_integer
        }

  def register_style(cellstyledb, style) do
    case Map.fetch(cellstyledb.cellstyles, style) do
      :error ->
        # add +1 here already since "0" refers to the default style
        csdb =
          update_in(
            cellstyledb.cellstyles,
            &Map.put(&1, style, cellstyledb.element_count + 1)
          )

        update_in(csdb.element_count, &(&1 + 1))

      {:ok, _} ->
        cellstyledb
    end
  end

  def get_id(cellstyledb, style) do
    case Map.fetch(cellstyledb.cellstyles, style) do
      :error ->
        raise %ArgumentError{message: "Could not find key in styledb: " <> inspect(style)}

      {:ok, key} ->
        key
    end
  end

  def id_sorted_styles(cellstyledb), do: DBUtil.id_sorted_values(cellstyledb.cellstyles)

  @doc ~S"""
  Recursively register all fonts, numberformat,
  border* and fill* properties (*=TBD)
  in the WorkbookCompInfo structure.
  """
  @spec register_all(WorkbookCompInfo.t()) :: WorkbookCompInfo.t()
  def register_all(wci) do
    Enum.reduce(wci.cellstyledb.cellstyles, wci, fn {style, _}, wci ->
      wci
      |> update_font(style.font)
      |> update_fill(style.fill)
      |> update_numfmt(style.numfmt)
      |> update_border(style.border)

      # TODO: update_in wci.borderstyledb ...; wci.fillstyledb...
    end)
  end

  defp update_border(wci, nil), do: wci

  defp update_border(wci, border),
    do: update_in(wci.borderstyledb, &BorderStyleDB.register_border(&1, border))

  defp update_fill(wci, nil), do: wci

  defp update_fill(wci, fill), do: update_in(wci.filldb, &FillDB.register_fill(&1, fill))

  defp update_font(wci, nil), do: wci

  defp update_font(wci, font), do: update_in(wci.fontdb, &FontDB.register_font(&1, font))

  defp update_numfmt(wci, nil), do: wci

  defp update_numfmt(wci, numfmt),
    do: update_in(wci.numfmtdb, &NumFmtDB.register_numfmt(&1, numfmt))
end