common_api.ex

# Pleroma: A lightweight social networking server
# Copyright © 2017-2019 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only

defmodule Pleroma.Web.CommonAPI do
  alias Pleroma.Activity
  alias Pleroma.Formatter
  alias Pleroma.Object
  alias Pleroma.ThreadMute
  alias Pleroma.User
  alias Pleroma.Web.ActivityPub.ActivityPub
  alias Pleroma.Web.ActivityPub.Utils
  alias Pleroma.Web.ActivityPub.Visibility

  import Pleroma.Web.Gettext
  import Pleroma.Web.CommonAPI.Utils

  def follow(follower, followed) do
    with {:ok, follower} <- User.maybe_direct_follow(follower, followed),
         {:ok, activity} <- ActivityPub.follow(follower, followed),
         {:ok, follower, followed} <-
           User.wait_and_refresh(
             Pleroma.Config.get([:activitypub, :follow_handshake_timeout]),
             follower,
             followed
           ) do
      {:ok, follower, followed, activity}
    end
  end

  def unfollow(follower, unfollowed) do
    with {:ok, follower, _follow_activity} <- User.unfollow(follower, unfollowed),
         {:ok, _activity} <- ActivityPub.unfollow(follower, unfollowed),
         {:ok, _unfollowed} <- User.unsubscribe(follower, unfollowed) do
      {:ok, follower}
    end
  end

  def accept_follow_request(follower, followed) do
    with {:ok, follower} <- User.follow(follower, followed),
         %Activity{} = follow_activity <- Utils.fetch_latest_follow(follower, followed),
         {:ok, follow_activity} <- Utils.update_follow_state_for_all(follow_activity, "accept"),
         {:ok, _activity} <-
           ActivityPub.accept(%{
             to: [follower.ap_id],
             actor: followed,
             object: follow_activity.data["id"],
             type: "Accept"
           }) do
      {:ok, follower}
    end
  end

  def reject_follow_request(follower, followed) do
    with %Activity{} = follow_activity <- Utils.fetch_latest_follow(follower, followed),
         {:ok, follow_activity} <- Utils.update_follow_state_for_all(follow_activity, "reject"),
         {:ok, _activity} <-
           ActivityPub.reject(%{
             to: [follower.ap_id],
             actor: followed,
             object: follow_activity.data["id"],
             type: "Reject"
           }) do
      {:ok, follower}
    end
  end

  def delete(activity_id, user) do
    with %Activity{data: %{"object" => _}} = activity <-
           Activity.get_by_id_with_object(activity_id),
         %Object{} = object <- Object.normalize(activity),
         true <- User.superuser?(user) || user.ap_id == object.data["actor"],
         {:ok, _} <- unpin(activity_id, user),
         {:ok, delete} <- ActivityPub.delete(object) do
      {:ok, delete}
    else
      _ ->
        {:error, dgettext("errors", "Could not delete")}
    end
  end

  def repeat(id_or_ap_id, user) do
    with %Activity{} = activity <- get_by_id_or_ap_id(id_or_ap_id),
         object <- Object.normalize(activity),
         nil <- Utils.get_existing_announce(user.ap_id, object) do
      ActivityPub.announce(user, object)
    else
      _ ->
        {:error, dgettext("errors", "Could not repeat")}
    end
  end

  def unrepeat(id_or_ap_id, user) do
    with %Activity{} = activity <- get_by_id_or_ap_id(id_or_ap_id),
         object <- Object.normalize(activity) do
      ActivityPub.unannounce(user, object)
    else
      _ ->
        {:error, dgettext("errors", "Could not unrepeat")}
    end
  end

  def favorite(id_or_ap_id, user) do
    with %Activity{} = activity <- get_by_id_or_ap_id(id_or_ap_id),
         object <- Object.normalize(activity),
         nil <- Utils.get_existing_like(user.ap_id, object) do
      ActivityPub.like(user, object)
    else
      _ ->
        {:error, dgettext("errors", "Could not favorite")}
    end
  end

  def unfavorite(id_or_ap_id, user) do
    with %Activity{} = activity <- get_by_id_or_ap_id(id_or_ap_id),
         object <- Object.normalize(activity) do
      ActivityPub.unlike(user, object)
    else
      _ ->
        {:error, dgettext("errors", "Could not unfavorite")}
    end
  end

  def vote(user, object, choices) do
    with "Question" <- object.data["type"],
         {:author, false} <- {:author, object.data["actor"] == user.ap_id},
         {:existing_votes, []} <- {:existing_votes, Utils.get_existing_votes(user.ap_id, object)},
         {options, max_count} <- get_options_and_max_count(object),
         option_count <- Enum.count(options),
         {:choice_check, {choices, true}} <-
           {:choice_check, normalize_and_validate_choice_indices(choices, option_count)},
         {:count_check, true} <- {:count_check, Enum.count(choices) <= max_count} do
      answer_activities =
        Enum.map(choices, fn index ->
          answer_data = make_answer_data(user, object, Enum.at(options, index)["name"])

          {:ok, activity} =
            ActivityPub.create(%{
              to: answer_data["to"],
              actor: user,
              context: object.data["context"],
              object: answer_data,
              additional: %{"cc" => answer_data["cc"]}
            })

          activity
        end)

      object = Object.get_cached_by_ap_id(object.data["id"])
      {:ok, answer_activities, object}
    else
      {:author, _} -> {:error, dgettext("errors", "Poll's author can't vote")}
      {:existing_votes, _} -> {:error, dgettext("errors", "Already voted")}
      {:choice_check, {_, false}} -> {:error, dgettext("errors", "Invalid indices")}
      {:count_check, false} -> {:error, dgettext("errors", "Too many choices")}
    end
  end

  defp get_options_and_max_count(object) do
    if Map.has_key?(object.data, "anyOf") do
      {object.data["anyOf"], Enum.count(object.data["anyOf"])}
    else
      {object.data["oneOf"], 1}
    end
  end

  defp normalize_and_validate_choice_indices(choices, count) do
    Enum.map_reduce(choices, true, fn index, valid ->
      index = if is_binary(index), do: String.to_integer(index), else: index
      {index, if(valid, do: index < count, else: valid)}
    end)
  end

  def get_visibility(%{"visibility" => visibility}, in_reply_to)
      when visibility in ~w{public unlisted private direct},
      do: {visibility, get_replied_to_visibility(in_reply_to)}

  def get_visibility(%{"visibility" => "list:" <> list_id}, in_reply_to) do
    visibility = {:list, String.to_integer(list_id)}
    {visibility, get_replied_to_visibility(in_reply_to)}
  end

  def get_visibility(_, in_reply_to) when not is_nil(in_reply_to) do
    visibility = get_replied_to_visibility(in_reply_to)
    {visibility, visibility}
  end

  def get_visibility(_, in_reply_to), do: {"public", get_replied_to_visibility(in_reply_to)}

  def get_replied_to_visibility(nil), do: nil

  def get_replied_to_visibility(activity) do
    with %Object{} = object <- Object.normalize(activity) do
      Pleroma.Web.ActivityPub.Visibility.get_visibility(object)
    end
  end

  def post(user, %{"status" => status} = data) do
    limit = Pleroma.Config.get([:instance, :limit])

    with status <- String.trim(status),
         attachments <- attachments_from_ids(data),
         in_reply_to <- get_replied_to_activity(data["in_reply_to_status_id"]),
         {visibility, in_reply_to_visibility} <- get_visibility(data, in_reply_to),
         {_, false} <-
           {:private_to_public, in_reply_to_visibility == "direct" && visibility != "direct"},
         {content_html, mentions, tags} <-
           make_content_html(
             status,
             attachments,
             data,
             visibility
           ),
         mentioned_users <- for({_, mentioned_user} <- mentions, do: mentioned_user.ap_id),
         addressed_users <- get_addressed_users(mentioned_users, data["to"]),
         {poll, poll_emoji} <- make_poll_data(data),
         {to, cc} <- get_to_and_cc(user, addressed_users, in_reply_to, visibility),
         context <- make_context(in_reply_to),
         cw <- data["spoiler_text"] || "",
         sensitive <- data["sensitive"] || Enum.member?(tags, {"#nsfw", "nsfw"}),
         full_payload <- String.trim(status <> cw),
         :ok <- validate_character_limit(full_payload, attachments, limit),
         object <-
           make_note_data(
             user.ap_id,
             to,
             context,
             content_html,
             attachments,
             in_reply_to,
             tags,
             cw,
             cc,
             sensitive,
             poll
           ),
         object <-
           Map.put(
             object,
             "emoji",
             Map.merge(Formatter.get_emoji_map(full_payload), poll_emoji)
           ) do
      preview? = Pleroma.Web.ControllerHelper.truthy_param?(data["preview"]) || false
      direct? = visibility == "direct"

      %{
        to: to,
        actor: user,
        context: context,
        object: object,
        additional: %{"cc" => cc, "directMessage" => direct?}
      }
      |> maybe_add_list_data(user, visibility)
      |> ActivityPub.create(preview?)
    else
      {:private_to_public, true} ->
        {:error, dgettext("errors", "The message visibility must be direct")}

      {:error, _} = e ->
        e

      e ->
        {:error, e}
    end
  end

  # Updates the emojis for a user based on their profile
  def update(user) do
    user =
      with emoji <- emoji_from_profile(user),
           source_data <- (user.info.source_data || %{}) |> Map.put("tag", emoji),
           info_cng <- User.Info.set_source_data(user.info, source_data),
           change <- Ecto.Changeset.change(user) |> Ecto.Changeset.put_embed(:info, info_cng),
           {:ok, user} <- User.update_and_set_cache(change) do
        user
      else
        _e ->
          user
      end

    ActivityPub.update(%{
      local: true,
      to: [user.follower_address],
      cc: [],
      actor: user.ap_id,
      object: Pleroma.Web.ActivityPub.UserView.render("user.json", %{user: user})
    })
  end

  def pin(id_or_ap_id, %{ap_id: user_ap_id} = user) do
    with %Activity{
           actor: ^user_ap_id,
           data: %{
             "type" => "Create"
           },
           object: %Object{
             data: %{
               "type" => "Note"
             }
           }
         } = activity <- get_by_id_or_ap_id(id_or_ap_id),
         true <- Visibility.is_public?(activity),
         %{valid?: true} = info_changeset <- User.Info.add_pinnned_activity(user.info, activity),
         changeset <-
           Ecto.Changeset.change(user) |> Ecto.Changeset.put_embed(:info, info_changeset),
         {:ok, _user} <- User.update_and_set_cache(changeset) do
      {:ok, activity}
    else
      %{errors: [pinned_activities: {err, _}]} ->
        {:error, err}

      _ ->
        {:error, dgettext("errors", "Could not pin")}
    end
  end

  def unpin(id_or_ap_id, user) do
    with %Activity{} = activity <- get_by_id_or_ap_id(id_or_ap_id),
         %{valid?: true} = info_changeset <-
           User.Info.remove_pinnned_activity(user.info, activity),
         changeset <-
           Ecto.Changeset.change(user) |> Ecto.Changeset.put_embed(:info, info_changeset),
         {:ok, _user} <- User.update_and_set_cache(changeset) do
      {:ok, activity}
    else
      %{errors: [pinned_activities: {err, _}]} ->
        {:error, err}

      _ ->
        {:error, dgettext("errors", "Could not unpin")}
    end
  end

  def add_mute(user, activity) do
    with {:ok, _} <- ThreadMute.add_mute(user.id, activity.data["context"]) do
      {:ok, activity}
    else
      {:error, _} -> {:error, dgettext("errors", "conversation is already muted")}
    end
  end

  def remove_mute(user, activity) do
    ThreadMute.remove_mute(user.id, activity.data["context"])
    {:ok, activity}
  end

  def thread_muted?(%{id: nil} = _user, _activity), do: false

  def thread_muted?(user, activity) do
    with [] <- ThreadMute.check_muted(user.id, activity.data["context"]) do
      false
    else
      _ -> true
    end
  end

  def report(user, data) do
    with {:account_id, %{"account_id" => account_id}} <- {:account_id, data},
         {:account, %User{} = account} <- {:account, User.get_cached_by_id(account_id)},
         {:ok, {content_html, _, _}} <- make_report_content_html(data["comment"]),
         {:ok, statuses} <- get_report_statuses(account, data),
         {:ok, activity} <-
           ActivityPub.flag(%{
             context: Utils.generate_context_id(),
             actor: user,
             account: account,
             statuses: statuses,
             content: content_html,
             forward: data["forward"] || false
           }) do
      {:ok, activity}
    else
      {:error, err} -> {:error, err}
      {:account_id, %{}} -> {:error, dgettext("errors", "Valid `account_id` required")}
      {:account, nil} -> {:error, dgettext("errors", "Account not found")}
    end
  end

  def update_report_state(activity_id, state) do
    with %Activity{} = activity <- Activity.get_by_id(activity_id),
         {:ok, activity} <- Utils.update_report_state(activity, state) do
      {:ok, activity}
    else
      nil -> {:error, :not_found}
      {:error, reason} -> {:error, reason}
      _ -> {:error, dgettext("errors", "Could not update state")}
    end
  end

  def update_activity_scope(activity_id, opts \\ %{}) do
    with %Activity{} = activity <- Activity.get_by_id_with_object(activity_id),
         {:ok, activity} <- toggle_sensitive(activity, opts),
         {:ok, activity} <- set_visibility(activity, opts) do
      {:ok, activity}
    else
      nil -> {:error, :not_found}
      {:error, reason} -> {:error, reason}
    end
  end

  defp toggle_sensitive(activity, %{"sensitive" => sensitive}) when sensitive in ~w(true false) do
    toggle_sensitive(activity, %{"sensitive" => String.to_existing_atom(sensitive)})
  end

  defp toggle_sensitive(%Activity{object: object} = activity, %{"sensitive" => sensitive})
       when is_boolean(sensitive) do
    new_data = Map.put(object.data, "sensitive", sensitive)

    {:ok, object} =
      object
      |> Object.change(%{data: new_data})
      |> Object.update_and_set_cache()

    {:ok, Map.put(activity, :object, object)}
  end

  defp toggle_sensitive(activity, _), do: {:ok, activity}

  defp set_visibility(activity, %{"visibility" => visibility}) do
    Utils.update_activity_visibility(activity, visibility)
  end

  defp set_visibility(activity, _), do: {:ok, activity}

  def hide_reblogs(user, muted) do
    ap_id = muted.ap_id

    if ap_id not in user.info.muted_reblogs do
      info_changeset = User.Info.add_reblog_mute(user.info, ap_id)
      changeset = Ecto.Changeset.change(user) |> Ecto.Changeset.put_embed(:info, info_changeset)
      User.update_and_set_cache(changeset)
    end
  end

  def show_reblogs(user, muted) do
    ap_id = muted.ap_id

    if ap_id in user.info.muted_reblogs do
      info_changeset = User.Info.remove_reblog_mute(user.info, ap_id)
      changeset = Ecto.Changeset.change(user) |> Ecto.Changeset.put_embed(:info, info_changeset)
      User.update_and_set_cache(changeset)
    end
  end
end