# Pleroma: A lightweight social networking server
# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only

defmodule Mix.Tasks.Pleroma.Database do
  alias Pleroma.Conversation
  alias Pleroma.Hashtag
  alias Pleroma.Maintenance
  alias Pleroma.Object
  alias Pleroma.Repo
  alias Pleroma.User

  require Logger
  require Pleroma.Constants

  import Ecto.Query
  import Mix.Pleroma

  use Mix.Task

  @shortdoc "A collection of database related tasks"
  @moduledoc File.read!("docs/administration/CLI_tasks/database.md")

  def run(["remove_embedded_objects" | args]) do
    {options, [], []} =
      OptionParser.parse(
        args,
        strict: [
          vacuum: :boolean
        ]
      )

    start_pleroma()
    Logger.info("Removing embedded objects")

    Repo.query!(
      "update activities set data = safe_jsonb_set(data, '{object}'::text[], data->'object'->'id') where data->'object'->>'id' is not null;",
      [],
      timeout: :infinity
    )

    if Keyword.get(options, :vacuum) do
      Maintenance.vacuum("full")
    end
  end

  def run(["bump_all_conversations"]) do
    start_pleroma()
    Conversation.bump_for_all_activities()
  end

  def run(["update_users_following_followers_counts"]) do
    start_pleroma()

    Repo.transaction(
      fn ->
        from(u in User, select: u)
        |> Repo.stream()
        |> Stream.each(&User.update_follower_count/1)
        |> Stream.run()
      end,
      timeout: :infinity
    )
  end

  def run(["prune_objects" | args]) do
    {options, [], []} =
      OptionParser.parse(
        args,
        strict: [
          vacuum: :boolean
        ]
      )

    start_pleroma()

    deadline = Pleroma.Config.get([:instance, :remote_post_retention_days])

    Logger.info("Pruning objects older than #{deadline} days")

    time_deadline =
      NaiveDateTime.utc_now()
      |> NaiveDateTime.add(-(deadline * 86_400))

    from(o in Object,
      where:
        fragment(
          "?->'to' \\? ? OR ?->'cc' \\? ?",
          o.data,
          ^Pleroma.Constants.as_public(),
          o.data,
          ^Pleroma.Constants.as_public()
        ),
      where: o.inserted_at < ^time_deadline,
      where:
        fragment("split_part(?->>'actor', '/', 3) != ?", o.data, ^Pleroma.Web.Endpoint.host())
    )
    |> Repo.delete_all(timeout: :infinity)

    if Keyword.get(options, :vacuum) do
      Maintenance.vacuum("full")
    end
  end

  def run(["fix_likes_collections"]) do
    start_pleroma()

    from(object in Object,
      where: fragment("(?)->>'likes' is not null", object.data),
      select: %{id: object.id, likes: fragment("(?)->>'likes'", object.data)}
    )
    |> Pleroma.Repo.chunk_stream(100, :batches)
    |> Stream.each(fn objects ->
      ids =
        objects
        |> Enum.filter(fn object -> object.likes |> Jason.decode!() |> is_map() end)
        |> Enum.map(& &1.id)

      Object
      |> where([object], object.id in ^ids)
      |> update([object],
        set: [
          data:
            fragment(
              "safe_jsonb_set(?, '{likes}', '[]'::jsonb, true)",
              object.data
            )
        ]
      )
      |> Repo.update_all([], timeout: :infinity)
    end)
    |> Stream.run()
  end

  def run(["transfer_hashtags"]) do
    import Ecto.Query

    start_pleroma()

    Logger.info("Starting transferring object embedded hashtags to `hashtags` table...")

    # Note: most objects have Mention-type AS2 tags and no hashtags (but we can't filter them out)
    from(
      object in Object,
      left_join: hashtag in assoc(object, :hashtags),
      where: is_nil(hashtag.id),
      where: fragment("(?)->>'tag' != '[]'", object.data),
      select: %{
        id: object.id,
        tag: fragment("(?)->>'tag'", object.data)
      }
    )
    |> Repo.chunk_stream(100, :batches, timeout: :infinity)
    |> Stream.each(fn objects ->
      Logger.info("Processing #{length(objects)} objects starting from id #{hd(objects).id}...")

      failed_ids =
        objects
        |> Enum.map(fn object ->
          hashtags = Object.object_data_hashtags(%{"tag" => Jason.decode!(object.tag)})

          Repo.transaction(fn ->
            with {:ok, hashtag_records} <- Hashtag.get_or_create_by_names(hashtags) do
              for hashtag_record <- hashtag_records do
                with {:ok, _} <-
                       Repo.query(
                         "insert into hashtags_objects(hashtag_id, object_id) values ($1, $2);",
                         [hashtag_record.id, object.id]
                       ) do
                  nil
                else
                  {:error, e} ->
                    error =
                      "ERROR: could not link object #{object.id} and hashtag " <>
                        "#{hashtag_record.id}: #{inspect(e)}"

                    Logger.error(error)
                    Repo.rollback(object.id)
                end
              end

              object.id
            else
              e ->
                error = "ERROR: could not create hashtags for object #{object.id}: #{inspect(e)}"
                Logger.error(error)
                Repo.rollback(object.id)
            end
          end)
        end)
        |> Enum.filter(&(elem(&1, 0) == :error))
        |> Enum.map(&elem(&1, 1))

      if Enum.any?(failed_ids) do
        Logger.error("ERROR: transfer_hashtags iteration failed for ids: #{inspect(failed_ids)}")
      end
    end)
    |> Stream.run()

    Logger.info("Done transferring hashtags. Please check logs to ensure no errors.")
  end

  def run(["vacuum", args]) do
    start_pleroma()

    Maintenance.vacuum(args)
  end

  def run(["ensure_expiration"]) do
    start_pleroma()
    days = Pleroma.Config.get([:mrf_activity_expiration, :days], 365)

    Pleroma.Activity
    |> join(:inner, [a], o in Object,
      on:
        fragment(
          "(?->>'id') = COALESCE((?)->'object'->> 'id', (?)->>'object')",
          o.data,
          a.data,
          a.data
        )
    )
    |> where(local: true)
    |> where([a], fragment("(? ->> 'type'::text) = 'Create'", a.data))
    |> where([_a, o], fragment("?->>'type' = 'Note'", o.data))
    |> Pleroma.Repo.chunk_stream(100, :batches)
    |> Stream.each(fn activities ->
      Enum.each(activities, fn activity ->
        expires_at =
          activity.inserted_at
          |> DateTime.from_naive!("Etc/UTC")
          |> Timex.shift(days: days)

        Pleroma.Workers.PurgeExpiredActivity.enqueue(%{
          activity_id: activity.id,
          expires_at: expires_at
        })
      end)
    end)
    |> Stream.run()
  end
end