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diff --git a/lib/pleroma/web/common_api/activity_draft.ex b/lib/pleroma/web/common_api/activity_draft.ex
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+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2022 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.CommonAPI.ActivityDraft do
+  alias Pleroma.Activity
+  alias Pleroma.Conversation.Participation
+  alias Pleroma.Object
+  alias Pleroma.Web.ActivityPub.Builder
+  alias Pleroma.Web.CommonAPI
+  alias Pleroma.Web.CommonAPI.Utils
+
+  import Pleroma.Web.Gettext
+
+  defstruct valid?: true,
+            errors: [],
+            user: nil,
+            params: %{},
+            status: nil,
+            summary: nil,
+            full_payload: nil,
+            attachments: [],
+            in_reply_to: nil,
+            in_reply_to_conversation: nil,
+            visibility: nil,
+            expires_at: nil,
+            extra: nil,
+            emoji: %{},
+            content_html: nil,
+            mentions: [],
+            tags: [],
+            to: [],
+            cc: [],
+            context: nil,
+            sensitive: false,
+            object: nil,
+            preview?: false,
+            changes: %{}
+
+  def new(user, params) do
+    %__MODULE__{user: user}
+    |> put_params(params)
+  end
+
+  def create(user, params) do
+    user
+    |> new(params)
+    |> status()
+    |> summary()
+    |> with_valid(&attachments/1)
+    |> full_payload()
+    |> expires_at()
+    |> poll()
+    |> with_valid(&in_reply_to/1)
+    |> with_valid(&in_reply_to_conversation/1)
+    |> with_valid(&visibility/1)
+    |> content()
+    |> with_valid(&to_and_cc/1)
+    |> with_valid(&context/1)
+    |> sensitive()
+    |> with_valid(&object/1)
+    |> preview?()
+    |> with_valid(&changes/1)
+    |> validate()
+  end
+
+  def listen(user, params) do
+    user
+    |> new(params)
+    |> visibility()
+    |> to_and_cc()
+    |> context()
+    |> listen_object()
+    |> with_valid(&changes/1)
+    |> validate()
+  end
+
+  defp listen_object(draft) do
+    object =
+      draft.params
+      |> Map.take([:album, :artist, :title, :length])
+      |> Map.new(fn {key, value} -> {to_string(key), value} end)
+      |> Map.put("type", "Audio")
+      |> Map.put("to", draft.to)
+      |> Map.put("cc", draft.cc)
+      |> Map.put("actor", draft.user.ap_id)
+
+    %__MODULE__{draft | object: object}
+  end
+
+  defp put_params(draft, params) do
+    params = Map.put_new(params, :in_reply_to_status_id, params[:in_reply_to_id])
+    %__MODULE__{draft | params: params}
+  end
+
+  defp status(%{params: %{status: status}} = draft) do
+    %__MODULE__{draft | status: String.trim(status)}
+  end
+
+  defp summary(%{params: params} = draft) do
+    %__MODULE__{draft | summary: Map.get(params, :spoiler_text, "")}
+  end
+
+  defp full_payload(%{status: status, summary: summary} = draft) do
+    full_payload = String.trim(status <> summary)
+
+    case Utils.validate_character_limit(full_payload, draft.attachments) do
+      :ok -> %__MODULE__{draft | full_payload: full_payload}
+      {:error, message} -> add_error(draft, message)
+    end
+  end
+
+  defp attachments(%{params: params} = draft) do
+    attachments = Utils.attachments_from_ids(params)
+    draft = %__MODULE__{draft | attachments: attachments}
+
+    case Utils.validate_attachments_count(attachments) do
+      :ok -> draft
+      {:error, message} -> add_error(draft, message)
+    end
+  end
+
+  defp in_reply_to(%{params: %{in_reply_to_status_id: ""}} = draft), do: draft
+
+  defp in_reply_to(%{params: %{in_reply_to_status_id: id}} = draft) when is_binary(id) do
+    %__MODULE__{draft | in_reply_to: Activity.get_by_id(id)}
+  end
+
+  defp in_reply_to(%{params: %{in_reply_to_status_id: %Activity{} = in_reply_to}} = draft) do
+    %__MODULE__{draft | in_reply_to: in_reply_to}
+  end
+
+  defp in_reply_to(draft), do: draft
+
+  defp in_reply_to_conversation(draft) do
+    in_reply_to_conversation = Participation.get(draft.params[:in_reply_to_conversation_id])
+    %__MODULE__{draft | in_reply_to_conversation: in_reply_to_conversation}
+  end
+
+  defp visibility(%{params: params} = draft) do
+    case CommonAPI.get_visibility(params, draft.in_reply_to, draft.in_reply_to_conversation) do
+      {visibility, "direct"} when visibility != "direct" ->
+        add_error(draft, dgettext("errors", "The message visibility must be direct"))
+
+      {visibility, _} ->
+        %__MODULE__{draft | visibility: visibility}
+    end
+  end
+
+  defp expires_at(draft) do
+    case CommonAPI.check_expiry_date(draft.params[:expires_in]) do
+      {:ok, expires_at} -> %__MODULE__{draft | expires_at: expires_at}
+      {:error, message} -> add_error(draft, message)
+    end
+  end
+
+  defp poll(draft) do
+    case Utils.make_poll_data(draft.params) do
+      {:ok, {poll, poll_emoji}} ->
+        %__MODULE__{draft | extra: poll, emoji: Map.merge(draft.emoji, poll_emoji)}
+
+      {:error, message} ->
+        add_error(draft, message)
+    end
+  end
+
+  defp content(draft) do
+    {content_html, mentioned_users, tags} = Utils.make_content_html(draft)
+
+    mentions =
+      mentioned_users
+      |> Enum.map(fn {_, mentioned_user} -> mentioned_user.ap_id end)
+      |> Utils.get_addressed_users(draft.params[:to])
+
+    %__MODULE__{draft | content_html: content_html, mentions: mentions, tags: tags}
+  end
+
+  defp to_and_cc(draft) do
+    {to, cc} = Utils.get_to_and_cc(draft)
+    %__MODULE__{draft | to: to, cc: cc}
+  end
+
+  defp context(draft) do
+    context = Utils.make_context(draft.in_reply_to, draft.in_reply_to_conversation)
+    %__MODULE__{draft | context: context}
+  end
+
+  defp sensitive(draft) do
+    sensitive = draft.params[:sensitive]
+    %__MODULE__{draft | sensitive: sensitive}
+  end
+
+  defp object(draft) do
+    emoji = Map.merge(Pleroma.Emoji.Formatter.get_emoji_map(draft.full_payload), draft.emoji)
+
+    # Sometimes people create posts with subject containing emoji,
+    # since subjects are usually copied this will result in a broken
+    # subject when someone replies from an instance that does not have
+    # the emoji or has it under different shortcode. This is an attempt
+    # to mitigate this by copying emoji from inReplyTo if they are present
+    # in the subject.
+    summary_emoji =
+      with %Activity{} <- draft.in_reply_to,
+           %Object{data: %{"tag" => [_ | _] = tag}} <- Object.normalize(draft.in_reply_to) do
+        Enum.reduce(tag, %{}, fn
+          %{"type" => "Emoji", "name" => name, "icon" => %{"url" => url}}, acc ->
+            if String.contains?(draft.summary, name) do
+              Map.put(acc, name, url)
+            else
+              acc
+            end
+
+          _, acc ->
+            acc
+        end)
+      else
+        _ -> %{}
+      end
+
+    emoji = Map.merge(emoji, summary_emoji)
+
+    {:ok, note_data, _meta} = Builder.note(draft)
+
+    object =
+      note_data
+      |> Map.put("emoji", emoji)
+      |> Map.put("source", %{
+        "content" => draft.status,
+        "mediaType" => Utils.get_content_type(draft.params[:content_type])
+      })
+      |> Map.put("generator", draft.params[:generator])
+
+    %__MODULE__{draft | object: object}
+  end
+
+  defp preview?(draft) do
+    preview? = Pleroma.Web.Utils.Params.truthy_param?(draft.params[:preview])
+    %__MODULE__{draft | preview?: preview?}
+  end
+
+  defp changes(draft) do
+    direct? = draft.visibility == "direct"
+    additional = %{"cc" => draft.cc, "directMessage" => direct?}
+
+    additional =
+      case draft.expires_at do
+        %DateTime{} = expires_at -> Map.put(additional, "expires_at", expires_at)
+        _ -> additional
+      end
+
+    changes =
+      %{
+        to: draft.to,
+        actor: draft.user,
+        context: draft.context,
+        object: draft.object,
+        additional: additional
+      }
+      |> Utils.maybe_add_list_data(draft.user, draft.visibility)
+
+    %__MODULE__{draft | changes: changes}
+  end
+
+  defp with_valid(%{valid?: true} = draft, func), do: func.(draft)
+  defp with_valid(draft, _func), do: draft
+
+  defp add_error(draft, message) do
+    %__MODULE__{draft | valid?: false, errors: [message | draft.errors]}
+  end
+
+  defp validate(%{valid?: true} = draft), do: {:ok, draft}
+  defp validate(%{errors: [message | _]}), do: {:error, message}
+end