akkoma/lib/pleroma/object/updater.ex
floatingghost 2641dcdd15 Post editing (#202)
Rebased from #103

Co-authored-by: Tusooa Zhu <tusooa@kazv.moe>
Co-authored-by: FloatingGhost <hannah@coffee-and-dreams.uk>
Reviewed-on: https://akkoma.dev/AkkomaGang/akkoma/pulls/202
2022-09-06 19:24:02 +00:00

241 lines
7.1 KiB
Elixir

# Pleroma: A lightweight social networking server
# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only
defmodule Pleroma.Object.Updater do
require Pleroma.Constants
def update_content_fields(orig_object_data, updated_object) do
Pleroma.Constants.status_updatable_fields()
|> Enum.reduce(
%{data: orig_object_data, updated: false},
fn field, %{data: data, updated: updated} ->
updated =
updated or
(field != "updated" and
Map.get(updated_object, field) != Map.get(orig_object_data, field))
data =
if Map.has_key?(updated_object, field) do
Map.put(data, field, updated_object[field])
else
Map.drop(data, [field])
end
%{data: data, updated: updated}
end
)
end
def maybe_history(object) do
with history <- Map.get(object, "formerRepresentations"),
true <- is_map(history),
"OrderedCollection" <- Map.get(history, "type"),
true <- is_list(Map.get(history, "orderedItems")),
true <- is_integer(Map.get(history, "totalItems")) do
history
else
_ -> nil
end
end
def history_for(object) do
with history when not is_nil(history) <- maybe_history(object) do
history
else
_ -> history_skeleton()
end
end
defp history_skeleton do
%{
"type" => "OrderedCollection",
"totalItems" => 0,
"orderedItems" => []
}
end
def maybe_update_history(
updated_object,
orig_object_data,
opts
) do
updated = opts[:updated]
use_history_in_new_object? = opts[:use_history_in_new_object?]
if not updated do
%{updated_object: updated_object, used_history_in_new_object?: false}
else
# Put edit history
# Note that we may have got the edit history by first fetching the object
{new_history, used_history_in_new_object?} =
with true <- use_history_in_new_object?,
updated_history when not is_nil(updated_history) <- maybe_history(opts[:new_data]) do
{updated_history, true}
else
_ ->
history = history_for(orig_object_data)
latest_history_item =
orig_object_data
|> Map.drop(["id", "formerRepresentations"])
updated_history =
history
|> Map.put("orderedItems", [latest_history_item | history["orderedItems"]])
|> Map.put("totalItems", history["totalItems"] + 1)
{updated_history, false}
end
updated_object =
updated_object
|> Map.put("formerRepresentations", new_history)
%{updated_object: updated_object, used_history_in_new_object?: used_history_in_new_object?}
end
end
defp maybe_update_poll(to_be_updated, updated_object) do
choice_key = fn data ->
if Map.has_key?(data, "anyOf"), do: "anyOf", else: "oneOf"
end
with true <- to_be_updated["type"] == "Question",
key <- choice_key.(updated_object),
true <- key == choice_key.(to_be_updated),
orig_choices <- to_be_updated[key] |> Enum.map(&Map.drop(&1, ["replies"])),
new_choices <- updated_object[key] |> Enum.map(&Map.drop(&1, ["replies"])),
true <- orig_choices == new_choices do
# Choices are the same, but counts are different
to_be_updated
|> Map.put(key, updated_object[key])
else
# Choices (or vote type) have changed, do not allow this
_ -> to_be_updated
end
end
# This calculates the data to be sent as the object of an Update.
# new_data's formerRepresentations is not considered.
# formerRepresentations is added to the returned data.
def make_update_object_data(original_data, new_data, date) do
%{data: updated_data, updated: updated} =
original_data
|> update_content_fields(new_data)
if not updated do
updated_data
else
%{updated_object: updated_data} =
updated_data
|> maybe_update_history(original_data, updated: updated, use_history_in_new_object?: false)
updated_data
|> Map.put("updated", date)
end
end
# This calculates the data of the new Object from an Update.
# new_data's formerRepresentations is considered.
def make_new_object_data_from_update_object(original_data, new_data) do
update_is_reasonable =
with {_, updated} when not is_nil(updated) <- {:cur_updated, new_data["updated"]},
{_, {:ok, updated_time, _}} <- {:cur_updated, DateTime.from_iso8601(updated)},
{_, last_updated} when not is_nil(last_updated) <-
{:last_updated, original_data["updated"] || original_data["published"]},
{_, {:ok, last_updated_time, _}} <-
{:last_updated, DateTime.from_iso8601(last_updated)},
:gt <- DateTime.compare(updated_time, last_updated_time) do
:update_everything
else
# only allow poll updates
{:cur_updated, _} -> :no_content_update
:eq -> :no_content_update
# allow all updates
{:last_updated, _} -> :update_everything
# allow no updates
_ -> false
end
%{
updated_object: updated_data,
used_history_in_new_object?: used_history_in_new_object?,
updated: updated
} =
if update_is_reasonable == :update_everything do
%{data: updated_data, updated: updated} =
original_data
|> update_content_fields(new_data)
updated_data
|> maybe_update_history(original_data,
updated: updated,
use_history_in_new_object?: true,
new_data: new_data
)
|> Map.put(:updated, updated)
else
%{
updated_object: original_data,
used_history_in_new_object?: false,
updated: false
}
end
updated_data =
if update_is_reasonable != false do
updated_data
|> maybe_update_poll(new_data)
else
updated_data
end
%{
updated_data: updated_data,
updated: updated,
used_history_in_new_object?: used_history_in_new_object?
}
end
def for_each_history_item(%{"orderedItems" => items} = history, _object, fun) do
new_items =
Enum.map(items, fun)
|> Enum.reduce_while(
{:ok, []},
fn
{:ok, item}, {:ok, acc} -> {:cont, {:ok, acc ++ [item]}}
e, _acc -> {:halt, e}
end
)
case new_items do
{:ok, items} -> {:ok, Map.put(history, "orderedItems", items)}
e -> e
end
end
def for_each_history_item(history, _, _) do
{:ok, history}
end
def do_with_history(object, fun) do
with history <- object["formerRepresentations"],
object <- Map.drop(object, ["formerRepresentations"]),
{_, {:ok, object}} <- {:main_body, fun.(object)},
{_, {:ok, history}} <- {:history_items, for_each_history_item(history, object, fun)} do
object =
if history do
Map.put(object, "formerRepresentations", history)
else
object
end
{:ok, object}
else
{:main_body, e} -> e
{:history_items, e} -> e
end
end
end