defmodule Kandis.Order do
  alias Kandis.Checkout
  alias Kandis.Pdfgenerator
  import Kandis.KdHelpers
  require Ecto.Query

  import HappyWith

  @invoice_nr_prefix Application.get_env(:kandis, :invoice_nr_prefix)
  @invoice_nr_testprefix Application.get_env(:kandis, :invoice_nr_testprefix)

  @local_order Application.get_env(:kandis, :local_order)
  @order_record Application.get_env(:kandis, :order_record)

  @server_view Application.get_env(:kandis, :server_view)
  @repo Application.get_env(:kandis, :repo)
  @translation_function Application.get_env(:kandis, :translation_function)

  @callback create_lineitem_from_cart_item(map(), map()) :: map()
  @callback apply_delivery_cost(map(), map()) :: map()

  def t(lang_or_context, translation_key, variables \\ []),
    do: @translation_function.(lang_or_context, translation_key, variables)

  def create_orderhtml(orderitems, ordervars, order_record \\ nil, mode \\ "order")
      when is_map(orderitems) and is_map(ordervars) do
    if function_exported?(@local_order, :create_orderhtml, 4) do
      @local_order.create_orderhtml(orderitems, ordervars, order_record, mode)
    else
      Phoenix.View.render(@server_view, "orderhtml.html", %{
        orderitems: orderitems,
        ordervars: ordervars,
        order: order_record,
        lang: orderitems.lang,
        mode: mode,
        invoicemode: mode == "invoice"
      })
    end
  end

  def create_orderitems(ordercart, ordervars) when is_map(ordercart) and is_map(ordervars) do
    %{
      lineitems: [],
      stats: %{},
      lang: ordercart.lang,
      cart_id: ordercart.cart_id,
      ordercart: ordercart
    }
    |> add_lineitems_from_cart(ordercart, ordervars)
    |> add_all_totals(ordervars)
  end

  def add_all_totals(orderitems, ordervars) when is_map(orderitems) and is_map(ordervars) do
    orderitems
    |> update_stats(ordervars)
    |> add_product_subtotal(t(orderitems.lang, "order.subtotal"))
    |> @local_order.apply_delivery_cost(ordervars)
    |> update_stats(ordervars)
    |> add_total(t(orderitems.lang, "order.total"))
    |> add_total_taxes(ordervars)
  end

  def remove_all_deleted(orderitems) do
    orderitems
    |> update_in([:lineitems], fn lineitems ->
      lineitems
      |> Enum.filter(&(&1[:deleted] == nil))
    end)
  end

  def remove_all_totals(orderitems) do
    orderitems
    |> update_in([:lineitems], fn lineitems ->
      lineitems
      |> Enum.filter(fn item -> !String.contains?("#{item[:type]}", ["total", "addon"]) end)
    end)
  end

  def add_total_taxes(%{stats: stats} = orderitems, _ordervars) do
    orderitems
    |> update_in([:lineitems], fn lineitems ->
      new_lineitems =
        stats.taxrates
        |> Map.to_list()
        |> Enum.map(fn {taxrate, tax_stats} ->
          %{
            title: t(orderitems.lang, "order.incl_tax", taxrate: taxrate),
            type: "total_tax",
            total_price: tax_stats.tax
          }
        end)

      lineitems ++ new_lineitems
    end)
  end

  def add_product_subtotal(%{stats: stats} = orderitems, title) when is_binary(title) do
    orderitems
    |> update_in([:lineitems], fn lineitems ->
      new_lineitem = %{
        title: title,
        type: "subtotal",
        total_price: stats.total_price
      }

      lineitems ++ [new_lineitem]
    end)
  end

  def add_total(%{stats: stats} = orderitems, title) when is_binary(title) do
    orderitems
    |> update_in([:lineitems], fn lineitems ->
      new_lineitem = %{
        title: title,
        type: "total",
        total_price: stats.total_price
      }

      lineitems = lineitems |> remove_subtotal_if_lastitem()

      lineitems ++ [new_lineitem]
    end)
  end

  def remove_subtotal_if_lastitem(lineitems) do
    last_item = List.last(lineitems)

    case last_item.type do
      "subtotal" -> List.delete_at(lineitems, length(lineitems) - 1)
      _ -> lineitems
    end
  end

  def add_lineitems_from_cart(orderitems, %{items: cartitems} = _ordercart, ordervars)
      when is_map(ordervars) do
    orderitems
    |> update_in([:lineitems], fn lineitems ->
      new_lineitems =
        cartitems
        |> Enum.map(&@local_order.create_lineitem_from_cart_item(&1, ordervars))
        |> Enum.filter(&Kandis.KdHelpers.present?/1)

      lineitems ++ new_lineitems
    end)
  end

  def update_stats(orderitems, _ordervars) do
    orderitems
    |> update_in([:stats], fn stats ->
      stats
      |> Map.merge(get_stats_for_lineitems(orderitems.lineitems))
    end)
  end

  def get_stats_for_lineitems(lineitems) do
    lineitems
    # skip totals:
    |> Enum.filter(fn a -> not String.contains?(a.type, "total") end)
    |> Enum.reduce(
      %{total_amount: 0, total_price: "0", total_product_price: "0", taxrates: %{}},
      fn item, acc ->
        acc
        |> update_in(
          [:total_amount],
          &(&1 + (item[:amount] || 0))
        )
        |> update_in([:total_price], &Decimal.add(&1, item.total_price))
        |> pipe_when(
          item.type == "product",
          update_in([:total_product_price], &Decimal.add(&1, item.total_price))
        )
        |> pipe_when(
          item[:taxrate],
          update_in([:taxrates], &update_taxrate_stats(&1, item))
        )
      end
    )
  end

  def update_taxrate_stats(taxrates = %{}, %{taxrate: taxrate} = item) do
    taxkey = "#{taxrate}"

    taxrate_item =
      taxrates[taxkey]
      |> if_empty(%{tax: "0", net: "0", gross: "0"})
      |> taxrate_item_append(create_taxrate_stats_entry_for_item(item))

    taxrates
    |> Map.put(taxkey, taxrate_item)
  end

  def update_taxrate_stats(taxes, _, _), do: taxes

  def taxrate_item_append(map, new_item) when is_map(map) and is_map(new_item) do
    new_item
    |> Map.to_list()
    |> Enum.reduce(map, fn {key, val}, acc ->
      acc
      |> update_in([key], &Decimal.add(&1, val))
    end)
    |> Map.new()
  end

  def update_ordervars(order_nr, nil) do
    case get_by_order_nr(order_nr) do
      order when is_map(order) -> {:ok, order}
      _ -> {:error, "no order found"}
    end
  end

  def update_ordervars(order_nr, new_ordervars)
      when is_map(new_ordervars) and is_binary(order_nr) do
    order = get_by_order_nr(order_nr)

    if MavuUtils.present?(new_ordervars) do
      updated_ordervars =
        order.ordervars
        |> Map.merge(new_ordervars)

      store_archive_version(order.order_nr)

      changes =
        %{ordervars: updated_ordervars}
        |> Map.merge(get_toplevel_order_fields(order.orderitems, updated_ordervars))

      {:ok, _updated_order} =
        order
        |> Ecto.Changeset.change(changes)
        |> Ecto.Changeset.change(%{version: order.version + 1})
        |> @repo.update()

      msg = "updated some order-variables"
      payload = %{new_ordervars: new_ordervars}
      # diff: generate_diff(order, updated_order)
      store_history_entry(order.order_nr, payload, msg)
    else
      {:ok, order}
    end
  end

  def update_orderitems(order_nr, nil) do
    case get_by_order_nr(order_nr) do
      order when is_map(order) -> {:ok, order}
      _ -> {:error, "no order found"}
    end
  end

  def update_orderitems(order_nr, new_orderitems)
      when is_map(new_orderitems) and is_binary(order_nr) do
    order = get_by_order_nr(order_nr)

    if MavuUtils.present?(new_orderitems) do
      updated_orderitems =
        merge_orderitem_changes(order.orderitems, new_orderitems)
        |> remove_all_deleted()
        |> remove_all_totals()
        |> add_all_totals(order.ordervars)

      store_archive_version(order.order_nr)

      changes =
        %{orderitems: updated_orderitems}
        |> Map.merge(get_toplevel_order_fields(updated_orderitems, order.ordervars))

      {:ok, updated_order} =
        order
        |> Ecto.Changeset.change(changes)
        |> Ecto.Changeset.change(%{version: order.version + 1})
        |> @repo.update()

      decrement_stock_for_order(updated_order)

      msg = "updated some order-items"
      payload = %{new_orderitems: new_orderitems}
      # diff: generate_diff(order, updated_order)
      store_history_entry(updated_order.order_nr, payload, msg)
    else
      {:ok, order}
    end
  end

  def merge_orderitem_changes(orderitems, orderitem_changes)
      when is_map(orderitems) and is_map(orderitem_changes) do
    {orderitems, orderitem_changes}
    |> IO.inspect(label: "mwuits-debug 2021-09-24_22:04 merge_orderitem_changes")

    orderitem_changes
    |> Map.to_list()
    |> Enum.reduce(orderitems, fn {name, values}, acc ->
      acc |> merge_orderitem_change(name, values)
    end)
    |> IO.inspect(label: "mwuits-debug 2021-09-24_22:04 CHANGED VALS")
  end

  def merge_orderitem_change(orderitems, name, new_values)
      when is_map(orderitems) and is_atom(name) and is_map(new_values) do
    case "#{name}" do
      "orderitem_" <> idx_str ->
        # incoming-index is 1-based:
        idx = MavuUtils.to_int(idx_str) - 1

        orderitems
        |> update_in([:lineitems, Access.at(idx)], fn item -> Map.merge(item, new_values) end)

      _ ->
        # return unchanged version
        orderitems
    end
  end

  def generate_diff(order, updated_order) do
    MapDiff.diff(order |> clean_for_diff(), updated_order |> clean_for_diff())
  end

  def clean_for_diff(order) when is_map(order) do
    Map.from_struct(order)
    |> Map.drop(~w(inserted_at updated_at archive history)a)
  end

  def store_history_entry(order_nr, payload, msg)
      when is_map(payload) and is_binary(msg) and is_binary(order_nr) do
    order = get_by_order_nr(order_nr)
    history_record = create_history_record(order, payload, msg)

    order
    |> Ecto.Changeset.change(%{history: (order.history || []) ++ [history_record]})
    |> @repo.update()
  end

  def store_archive_version(order_nr) when is_binary(order_nr) do
    order = get_by_order_nr(order_nr)
    version_record = create_version_record(order)

    order
    |> Ecto.Changeset.change(%{archive: (order.archive || []) ++ [version_record]})
    |> @repo.update()
  end

  def erase_archive(order_nr) when is_binary(order_nr) do
    order = get_by_order_nr(order_nr)
    version_record = create_version_record(order)

    order
    |> Ecto.Changeset.change(%{archive: []})
    |> @repo.update()

    {:ok, version_record}
  end

  def restore_archive_version(order_nr, version)
      when is_integer(version) and is_binary(order_nr) do
    order = get_by_order_nr(order_nr)
    version_record = get_version_record(order, version)

    {:ok, updated_order} =
      order
      |> Ecto.Changeset.change(%{
        version: order.version + 1,
        ordervars: version_record.ordervars,
        orderitems: version_record.orderitems
      })
      |> @repo.update()

    decrement_stock_for_order(updated_order)

    msg = "restored from version ##{version}"
    payload = %{source_version: version, target_version: updated_order.version}
    # diff: generate_diff(order, updated_order)
    store_history_entry(updated_order.order_nr, payload, msg)
  end

  def erase_history(order_nr) when is_binary(order_nr) do
    order = get_by_order_nr(order_nr)
    version_record = create_version_record(order)

    order
    |> Ecto.Changeset.change(%{history: []})
    |> @repo.update()

    {:ok, version_record}
  end

  def create_version_record(order) when is_map(order) do
    order
    |> Map.take(~w(ordervars orderitems state version)a)
    |> Map.put(:_ts, create_version_timestamp())
  end

  def get_version_record(order, version) when is_integer(version) and is_map(order) do
    order.archive
    |> Enum.find(&(&1["version"] == version))
    |> case do
      nil ->
        nil

      rec ->
        %{
          ordervars: rec["ordervars"] |> AtomicMap.convert(safe: true, ignore: true),
          orderitems: rec["orderitems"] |> AtomicMap.convert(safe: true, ignore: true)
        }
    end
  end

  def create_history_record(order, payload, msg)
      when is_map(payload) and is_binary(msg) and is_map(order) do
    payload
    |> Map.put(:_version, order.version)
    |> Map.put(:_ts, create_version_timestamp())
    |> Map.put(:_msg, msg)
  end

  def create_version_timestamp(),
    do:
      DateTime.utc_now()
      |> DateTime.truncate(:second)
      |> to_string()
      |> String.replace_suffix("Z", "")

  def create_taxrate_stats_entry_for_item(item) do
    taxfactor = Decimal.div(item.taxrate, 100)
    gross = item.total_price
    net = Decimal.div(item.total_price, Decimal.add(taxfactor, 1))
    tax = Decimal.sub(gross, net)
    %{tax: tax, net: net, gross: gross}
  end

  def extract_shipping_address_fields(ordervars) when is_map(ordervars) do
    ordervars
    |> Map.to_list()
    |> Enum.filter(&String.starts_with?(to_string(elem(&1, 0)), "shipping_"))
    |> Enum.map(fn {key, val} ->
      {String.trim_leading(to_string(key), "shipping_") |> String.to_existing_atom(), val}
    end)
    |> Map.new()
  end

  def atomize_maps(rec) when is_map(rec) do
    rec
    |> update_in([:orderitems], &AtomicMap.convert(&1, safe: true, ignore: true))
    |> update_in([:ordervars], &AtomicMap.convert(&1, safe: true, ignore: true))
  end

  def atomize_maps(val), do: val

  def get_by_id(id) when is_integer(id) do
    @repo.get(@order_record, id)
    |> atomize_maps()
  end

  def get_by_cart_id(cart_id) when is_binary(cart_id) do
    @order_record
    |> Ecto.Query.where([o], o.cart_id == ^cart_id)
    |> Ecto.Query.where([o], o.state != "cancelled")
    |> @repo.one()
    |> atomize_maps()
  end

  def get_by_order_nr(order_nr) when is_binary(order_nr) do
    @repo.get_by(@order_record, order_nr: order_nr)
    |> atomize_maps()
  end

  def get_by_order_nr(nil), do: nil

  def get_by_invoice_nr(invoice_nr) when is_binary(invoice_nr) do
    @repo.get_by(@order_record, invoice_nr: invoice_nr)
    |> atomize_maps()
  end

  def get_by_any_id(any_id) when is_binary(any_id) do
    cond do
      String.starts_with?(any_id, @invoice_nr_prefix) -> get_by_invoice_nr(any_id)
      String.starts_with?(any_id, @invoice_nr_testprefix) -> get_by_invoice_nr(any_id)
      true -> get_by_order_nr(any_id)
    end
  end

  def get_by_any_id(any_id) when is_integer(any_id) do
    get_by_id(any_id)
  end

  def get_by_any_id(%_{} = order) when is_struct(order) do
    order
  end

  def create_new_order(orderitems, ordervars) do
    @repo.transaction(fn ->
      data = create_order_record_from_checkout(orderitems, ordervars)

      struct(@order_record)
      |> @order_record.changeset(data)
      |> @repo.insert()
    end)
    |> case do
      {:ok, {:ok, %_{} = order}} ->
        order

      _ ->
        nil
    end
  end

  def set_state(any_id, new_status) do
    {any_id, new_status} |> Kandis.KdHelpers.log("attempt to set status of order ", :info)

    get_by_any_id(any_id)
    |> @order_record.changeset(%{state: new_status})
    |> @repo.update()
    |> case do
      {:ok, order} ->
        case new_status do
          "cancelled" -> Task.start(fn -> update_stock(order) end)
          _ -> nil
        end

        order

      {:error, _err} ->
        raise "cannot set state on #{any_id}"
    end
  end

  def remove_invoice_nr(order) when is_map(order) do
    {order.order_nr} |> Kandis.KdHelpers.log("attempt to remove_invoice_nr of order ", :info)

    order
    |> @order_record.changeset(%{invoice_nr: nil})
    |> @repo.update()
  end

  def decrement_stock_for_order(%_{} = order) do
    sku_amounts_from_items =
      order.orderitems.lineitems
      |> Enum.filter(&(&1.type == "product"))
      |> Enum.map(&%{sku: &1.sku, amount: &1.amount})

    Enum.map(sku_amounts_from_items, &decrement_stock_for_sku(&1.sku, &1.amount, order))

    # set remaining stock items to 0 (e.g. after editing an order)
    skus_from_stock = get_sku_amounts_in_order(order) |> Enum.map(& &1.sku)
    skus_from_items = sku_amounts_from_items |> Enum.map(& &1.sku)

    hidden_skus = skus_from_stock -- skus_from_items
    Enum.map(hidden_skus, &decrement_stock_for_sku(&1, 0, order))

    update_stock(order)
    order
  end

  def get_sku_amounts_in_order(order) do
    @local_order.get_sku_amounts_in_order(order)
  end

  def decrement_stock_for_sku(sku, amount, order) do
    @local_order.decrement_stock_for_sku(sku, amount, order)
  end

  def update_stock(order) do
    @local_order.update_stock(order)
  end

  def create_order_record_from_checkout(orderitems, ordervars)
      when is_map(orderitems) and is_map(ordervars) do
    %{
      ordervars: ordervars,
      orderitems: orderitems,
      cart_id: orderitems.cart_id,
      order_nr: create_new_order_nr(is_testorder?(orderitems, ordervars)),
      state: "created",
      user_id: ordervars[:user_id],
      email: ordervars[:email],
      payment_type: ordervars[:payment_type],
      delivery_type: ordervars[:delivery_type],
      shipping_country: Checkout.get_shipping_country(ordervars),
      total_price: array_get(orderitems, [:stats, :total_price])
    }
  end

  def get_toplevel_order_fields(orderitems, ordervars)
      when is_map(orderitems) and is_map(ordervars) do
    %{
      email: ordervars[:email],
      payment_type: ordervars[:payment_type],
      delivery_type: ordervars[:delivery_type],
      shipping_country: Checkout.get_shipping_country(ordervars),
      total_price: to_dec(array_get(orderitems, [:stats, :total_price])),
      tags: ordervars[:tags]
    }
  end

  def is_testorder?(orderitems, _ordervars) do
    # orders <=1 EUR are considered test-orders
    Decimal.cmp(array_get(orderitems, [:stats, :total_price], "100"), "1.01") == :lt
  end

  def is_invoiced?(order) do
    MavuUtils.present?(order[:invoice_nr])
  end

  def is_cancelled?(order) do
    order[:state] == "cancelled"
  end

  def create_new_order_nr(is_testmode \\ false) do
    nr =
      if is_testmode do
        get_order_nr_prefix() <> "-TEST-" <> get_random_code(4)
      else
        get_order_nr_prefix() <> "-" <> get_random_code(4)
      end

    if order_nr_taken?(nr) do
      create_new_order_nr(is_testmode)
    else
      nr
    end
  end

  def order_nr_taken?(order_nr) when is_binary(order_nr) do
    case get_by_order_nr(order_nr) do
      nil -> false
      _ -> true
    end
  end

  def get_random_code(length) do
    Enum.shuffle(~w( A B C D E G H J K L M N P R S T U V X))
    |> Enum.join("")
    |> String.slice(1..length)
  end

  def get_order_nr_prefix() do
    Date.utc_today()
    |> Date.to_string()
    |> String.slice(0..-4)
    |> String.replace("-", "")
  end

  def update(data, _params \\ nil) do
    case data do
      %{"id" => id} -> get_by_id(id)
      %{id: id} -> get_by_id(id)
      %{"order_nr" => order_nr} -> get_by_order_nr(order_nr)
      %{order_nr: order_nr} -> get_by_order_nr(order_nr)
    end
    |> @order_record.changeset(data)
    |> @repo.insert_or_update()
  end

  def get_order_query(params) do
    id = params["id"]
    state = params["state"]

    @order_record
    |> pipe_when(id, Ecto.Query.where([o], o.id == ^id))
    |> pipe_when(state, Ecto.Query.where([o], o.state == ^state))
    |> Ecto.Query.order_by([o], desc: o.id)
  end

  def get_orders(params) do
    get_order_query(params)
    |> @repo.all()
  end

  def get_orderhtml(%_{} = order, mode \\ "order") do
    create_orderhtml(order.orderitems, order.ordervars, order, mode)
  end

  def get_current_order_for_vid(vid, params \\ %{}) when is_binary(vid) and is_map(params) do
    with _cart = %{cart_id: cart_id} <- Kandis.Cart.get_cart_record(vid),
         %_{} = order <- get_by_cart_id(cart_id) do
      order
    else
      _err -> get_by_order_nr(params["order_nr"])
    end
    |> Kandis.KdHelpers.log("get_current_order_for_vid(#{vid})", :info)
  end

  def get_latest_order_for_vid(vid, params \\ %{}) when is_binary(vid) and is_map(params) do
    with _cart = %{cart_id: cart_id} <- Kandis.Cart.get_cart_record(vid),
         %_{} = firstorder <- get_all_by_cart_id(cart_id) |> hd(),
         %_{} = order <- firstorder |> atomize_maps do
      order
    else
      _err -> get_by_order_nr(params["order_nr"])
    end
  end

  def get_all_by_cart_id(cart_id) do
    @order_record
    |> Ecto.Query.where([o], o.cart_id == ^cart_id)
    |> Ecto.Query.where([o], o.state != "cancelled")
    |> Ecto.Query.order_by([o], desc: o.id)
    |> @repo.all()
  end

  # invoice functions

  def delete_latest_invoice(invoice_nr) when is_binary(invoice_nr) do
    happy_with do
      @get_latest_invoice_nr latest_invoice_nr <- get_latest_invoice_nr(get_invoice_nr_prefix())
      @ensure_invoice_nr_is_latest a when a == true <- latest_invoice_nr == invoice_nr
      @get_order order when is_map(order) <- get_by_invoice_nr(latest_invoice_nr)
      @get_file filename when is_binary(filename) <- get_invoice_file(order.order_nr)
      @remove_invoice_file :ok <- File.rm(filename)
      @remove_invoice_nr_from_order {:ok, order} <- remove_invoice_nr(order)
      {:ok, latest_invoice_nr, order}
    else
      {error_tag, error_context} ->
        error_context |> MavuUtils.log(msg = "cannot '#{error_tag}'", :error)
        {:error, msg, error_context}
    end
  end

  def get_invoice_file(any_id, params \\ %{}) when is_binary(any_id) or is_integer(any_id),
    do: get_order_file(any_id, "invoice", params)

  def get_order_file(any_id, mode, params \\ %{})

  def get_order_file(any_id, "invoice" = mode, params)
      when is_binary(any_id) or is_integer(any_id) do
    order = get_by_any_id(any_id)

    case order do
      %{invoice_nr: invoice_nr} when is_binary(invoice_nr) -> {:ok, invoice_nr}
      %{order_nr: order_nr} -> create_and_assign_new_invoice_nr_for_order(order_nr)
    end

    Pdfgenerator.get_pdf_file_for_order_nr(order.order_nr, order.version, mode, params)
  end

  def get_order_file(any_id, mode, params) when is_binary(any_id) or is_integer(any_id) do
    order = get_by_any_id(any_id)

    Pdfgenerator.get_pdf_file_for_order_nr(order.order_nr, order.version, mode, params)
  end

  def get_invoice_url(any_id, params \\ %{}) when is_binary(any_id) or is_integer(any_id),
    do: get_order_file_url(any_id, "invoice", params)

  def get_order_file_url(any_id, mode, params \\ %{})
      when is_binary(mode) and (is_binary(any_id) or is_integer(any_id)) do
    get_order_file(any_id, mode, params)
    |> Pdfgenerator.get_url_for_file()
  end

  def create_new_invoice_nr(prefix) do
    get_latest_invoice_nr(prefix)
    |> increment_invoice_nr(prefix)
  end

  def get_invoice_nr_prefix(:test), do: @invoice_nr_testprefix
  def get_invoice_nr_prefix(:live), do: @invoice_nr_prefix

  def get_invoice_nr_prefix(), do: get_invoice_nr_prefix(:live)

  def increment_invoice_nr(invoice_nr, prefix) do
    nr = invoice_nr |> String.trim_leading(prefix) |> to_int() |> if_nil(0)
    nr = nr + 1
    "#{prefix}#{nr}"
  end

  def order_nr_is_testmode?(order_nr) when is_binary(order_nr) do
    String.contains?(order_nr, "-TEST-")
  end

  def create_and_assign_new_invoice_nr_for_order(order_nr, tries \\ 0)

  def create_and_assign_new_invoice_nr_for_order(order_nr, tries) when tries > 100 do
    {:error, "could not create new invoice nr for order #{order_nr} after #{tries} tries "}
  end

  def create_and_assign_new_invoice_nr_for_order(order_nr, tries)
      when is_binary(order_nr) do
    inv_prefix =
      if order_nr_is_testmode?(order_nr) do
        @invoice_nr_testprefix
      else
        @invoice_nr_prefix
      end

    new_invoice_nr = create_new_invoice_nr(inv_prefix)

    %{order_nr: order_nr, invoice_nr: new_invoice_nr}
    |> Kandis.Order.update()
    |> case do
      {:ok, record} ->
        {:ok, record[:invoice_nr]}

      {:error,
       %Ecto.Changeset{errors: [invoice_nr: {_, [constraint: :unique, constraint_name: _]}]}} ->
        # try_again
        create_and_assign_new_invoice_nr_for_order(order_nr, tries + 1)

      {:error, error} ->
        {:error, error}
    end
  end

  def finish_order(order_nr) when is_binary(order_nr) do
    order = get_by_order_nr(order_nr)

    if order.state == "w4payment" do
      set_state(order_nr, "paid")
      Checkout.reset_checkout(order)
    end

    order = get_by_order_nr(order_nr)

    @local_order.finish_order(order)
  end

  def get_latest_invoice_nr(prefix) do
    invlike = "#{prefix}%"

    @order_record
    |> Ecto.Query.where([o], like(o.invoice_nr, ^invlike))
    |> @repo.aggregate(:max, :invoice_nr)
    |> if_nil("#{prefix}#{10000}")
  end

  def cancel_orders_for_cart_id(cart_id) when is_binary(cart_id) do
    @order_record
    |> Ecto.Query.where([o], o.cart_id == ^cart_id)
    |> Ecto.Query.where([o], o.state == "w4payment")
    |> Ecto.Query.update(set: [state: "cancelled"])
    |> @repo.update_all([])
  end

  def cancel_expired_orders(n \\ 100) do
    get_expired_orders()
    |> Enum.take(n)
    |> Enum.map(fn order_nr -> set_state(order_nr, "cancelled") end)
  end

  def get_expired_orders() do
    expire_minutes = 30
    expire_time = DateTime.utc_now() |> DateTime.add(expire_minutes * -60, :second)

    @order_record
    |> Ecto.Query.where([r], r.state == "w4payment")
    |> Ecto.Query.where([r], r.updated_at <= ^expire_time)
    |> Ecto.Query.select([r], r.order_nr)
    |> @repo.all()
  end

  def get_history_list(order) when is_map(order) do
    ([get_version_one_record(order)] ++
       case order[:history] do
         nil -> []
         a -> a
       end)
    |> Enum.map(&AtomicMap.convert(&1, safe: true, ignore: true))
  end

  def get_version_one_record(order) do
    %{
      "_msg" => "order created",
      "_ts" =>
        order.inserted_at
        |> NaiveDateTime.truncate(:second)
        |> to_string()
        |> String.replace_suffix("Z", ""),
      "_version" => 1
    }
  end
end