defmodule WorkloadService.Aggregates.QuoteTask do
  use WorkloadService.Aggregates.Task,
    task_type: "quote",
    commands: WorkloadService.Commands.QuoteTask,
    submission_type: map()

  def validate_submission(submission) when is_map(submission) do
    with {:ok, quote_id} <- validate_required_string(submission, "quote_id"),
         {:ok, recorded_by} <- validate_required_string(submission, "recorded_by"),
         {:ok, valid_until} <- validate_date_string(submission, "valid_until"),
         {:ok, plans} <- validate_plans(submission["plans"]) do
      :ok
    end
  end

  def validate_submission(_), do: {:error, :invalid_submission_format}

  defp validate_required_string(submission, field) do
    case Map.get(submission, field) do
      nil -> {:error, {:missing_field, field}}
      value when is_binary(value) and byte_size(value) > 0 -> {:ok, value}
      _ -> {:error, {:invalid_field, field}}
    end
  end

  defp validate_date_string(submission, field) do
    case Map.get(submission, field) do
      nil -> {:error, {:missing_field, field}}
      value when is_binary(value) ->
        case Date.from_iso8601(value) do
          {:ok, _date} -> {:ok, value}
          {:error, _} -> {:error, {:invalid_date_format, field}}
        end
      _ -> {:error, {:invalid_field, field}}
    end
  end

  defp validate_plans(plans) when is_list(plans) do
    if length(plans) == 0 do
      {:error, :no_plans_provided}
    else
      case Enum.reduce_while(plans, :ok, fn plan, _acc ->
        validate_plan(plan)
      end) do
        :ok -> {:ok, plans}
        error -> error
      end
    end
  end

  defp validate_plans(_), do: {:error, :invalid_plans_format}

  defp validate_plan(plan) when is_map(plan) do
    with {:ok, plan_id} <- validate_required_string(plan, "plan_id"),
         {:ok, name} <- validate_required_string(plan, "name"),
         {:ok, premium} <- validate_premium(plan["premium"]),
         {:ok, coverage_details} <- validate_coverage_details(plan["coverage_details"]) do
      {:cont, :ok}
    end
  end

  defp validate_plan(_), do: {:halt, {:error, :invalid_plan_format}}

  defp validate_premium(premium) when is_number(premium) and premium > 0, do: {:ok, premium}
  defp validate_premium(_), do: {:error, :invalid_premium}

  defp validate_coverage_details(details) when is_map(details), do: {:ok, details}
  defp validate_coverage_details(_), do: {:error, :invalid_coverage_details}
end