defmodule Aprs.Workers.PacketCleanupWorker do
  @moduledoc """
  Oban worker for cleaning up old APRS packet data.

  This worker is responsible for:
  1. Removing packets older than the retention period (1 year by default)
  2. Providing granular cleanup with custom age parameters
  3. Logging statistics about cleanup operations

  ## Functions
  - `perform/1` - Standard cleanup using configured retention period
  - `cleanup_packets_older_than/1` - Cleanup packets older than specified days
  - `schedule_cleanup/0` - Schedule standard cleanup job
  - `schedule_cleanup_for_age/1` - Schedule cleanup with custom age parameter
  - `schedule_daily_cleanup/0` - Schedule daily cleanup at midnight UTC
  """

  use Oban.Worker, queue: :maintenance, max_attempts: 3

  # Import modules needed for database operations

  alias Aprs.Packet
  alias Aprs.Packets
  alias Aprs.Repo

  require Logger

  @impl Oban.Worker
  def perform(%Oban.Job{args: %{"cleanup_days" => days}}) when is_integer(days) do
    Logger.info("Starting scheduled APRS packet cleanup for packets older than #{days} days")

    # Count packets before cleanup for statistics
    _total_before = count_total_packets()

    # Perform the cleanup of old packets with custom age
    deleted_count = Packets.clean_packets_older_than(days)

    # Log results
    Logger.info("APRS packet cleanup complete: removed #{deleted_count} packets older than #{days} days")

    # Return success
    :ok
  end

  def perform(%Oban.Job{args: _args}) do
    Logger.info("Starting scheduled APRS packet cleanup")

    # Count packets before cleanup for statistics
    _total_before = count_total_packets()

    # Perform the cleanup of old packets (older than 1 year by default)
    deleted_count = cleanup_old_packets()

    # Log results
    retention_days = Application.get_env(:aprs, :packet_retention_days, 365)
    Logger.info("APRS packet cleanup complete: removed #{deleted_count} packets older than #{retention_days} days")

    # Return success
    :ok
  end

  # Schedule this job to run daily
  def schedule_cleanup do
    %{}
    |> Oban.Job.new(worker: __MODULE__, queue: :maintenance)
    |> Oban.insert()
  end

  # Schedule cleanup with custom age parameter
  def schedule_cleanup_for_age(days) when is_integer(days) and days > 0 do
    %{"cleanup_days" => days}
    |> Oban.Job.new(worker: __MODULE__, queue: :maintenance)
    |> Oban.insert()
  end

  # Schedule this job to run daily at midnight UTC
  def schedule_daily_cleanup do
    # Calculate when the next midnight UTC is
    now = DateTime.utc_now()
    tomorrow = Date.add(now, 1)

    next_midnight = %{
      now
      | year: tomorrow.year,
        month: tomorrow.month,
        day: tomorrow.day,
        hour: 0,
        minute: 0,
        second: 0,
        microsecond: {0, 6}
    }

    # Schedule the job
    %{}
    |> Oban.Job.new(worker: __MODULE__, queue: :maintenance)
    |> Oban.insert(scheduled_at: next_midnight)
  end

  defp count_total_packets do
    Repo.aggregate(Packet, :count, :id)
  end

  defp cleanup_old_packets do
    # Use the existing function from Packets context
    Packets.clean_old_packets()
  end

  @doc """
  Perform cleanup of packets older than a specific number of days.

  This function provides more granular control over packet cleanup operations.

  ## Parameters
  - `days` - Number of days to retain packets (packets older than this will be deleted)

  ## Returns
  - Number of packets deleted
  """
  def cleanup_packets_older_than(days) when is_integer(days) and days > 0 do
    Logger.info("Starting APRS packet cleanup for packets older than #{days} days")

    deleted_count = Packets.clean_packets_older_than(days)

    Logger.info("APRS packet cleanup complete: removed #{deleted_count} packets older than #{days} days")

    deleted_count
  end
end