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

defmodule Pleroma.Web.AdminAPI.AdminAPIController do
  use Pleroma.Web, :controller

  import Pleroma.Web.ControllerHelper, only: [json_response: 3]

  alias Pleroma.Config
  alias Pleroma.MFA
  alias Pleroma.ModerationLog
  alias Pleroma.Stats
  alias Pleroma.User
  alias Pleroma.Web.ActivityPub.ActivityPub
  alias Pleroma.Web.ActivityPub.Builder
  alias Pleroma.Web.ActivityPub.Pipeline
  alias Pleroma.Web.AdminAPI
  alias Pleroma.Web.AdminAPI.AccountView
  alias Pleroma.Web.AdminAPI.ModerationLogView
  alias Pleroma.Web.AdminAPI.Search
  alias Pleroma.Web.Endpoint
  alias Pleroma.Web.Plugs.OAuthScopesPlug
  alias Pleroma.Web.Router

  require Logger

  @users_page_size 50

  plug(
    OAuthScopesPlug,
    %{scopes: ["read:accounts"], admin: true}
    when action in [:list_users, :user_show, :right_get, :show_user_credentials, :create_backup]
  )

  plug(
    OAuthScopesPlug,
    %{scopes: ["write:accounts"], admin: true}
    when action in [
           :get_password_reset,
           :force_password_reset,
           :user_delete,
           :users_create,
           :user_toggle_activation,
           :user_activate,
           :user_deactivate,
           :user_approve,
           :tag_users,
           :untag_users,
           :right_add,
           :right_add_multiple,
           :right_delete,
           :disable_mfa,
           :right_delete_multiple,
           :update_user_credentials
         ]
  )

  plug(
    OAuthScopesPlug,
    %{scopes: ["write:follows"], admin: true}
    when action in [:user_follow, :user_unfollow]
  )

  plug(
    OAuthScopesPlug,
    %{scopes: ["read:statuses"], admin: true}
    when action in [:list_user_statuses, :list_instance_statuses]
  )

  plug(
    OAuthScopesPlug,
    %{scopes: ["read:chats"], admin: true}
    when action in [:list_user_chats]
  )

  plug(
    OAuthScopesPlug,
    %{scopes: ["read"], admin: true}
    when action in [
           :list_log,
           :stats,
           :need_reboot
         ]
  )

  plug(
    OAuthScopesPlug,
    %{scopes: ["write"], admin: true}
    when action in [
           :restart,
           :resend_confirmation_email,
           :confirm_email,
           :reload_emoji
         ]
  )

  action_fallback(AdminAPI.FallbackController)

  def user_delete(conn, %{"nickname" => nickname}) do
    user_delete(conn, %{"nicknames" => [nickname]})
  end

  def user_delete(%{assigns: %{user: admin}} = conn, %{"nicknames" => nicknames}) do
    users =
      nicknames
      |> Enum.map(&User.get_cached_by_nickname/1)

    users
    |> Enum.each(fn user ->
      {:ok, delete_data, _} = Builder.delete(admin, user.ap_id)
      Pipeline.common_pipeline(delete_data, local: true)
    end)

    ModerationLog.insert_log(%{
      actor: admin,
      subject: users,
      action: "delete"
    })

    json(conn, nicknames)
  end

  def user_follow(%{assigns: %{user: admin}} = conn, %{
        "follower" => follower_nick,
        "followed" => followed_nick
      }) do
    with %User{} = follower <- User.get_cached_by_nickname(follower_nick),
         %User{} = followed <- User.get_cached_by_nickname(followed_nick) do
      User.follow(follower, followed)

      ModerationLog.insert_log(%{
        actor: admin,
        followed: followed,
        follower: follower,
        action: "follow"
      })
    end

    json(conn, "ok")
  end

  def user_unfollow(%{assigns: %{user: admin}} = conn, %{
        "follower" => follower_nick,
        "followed" => followed_nick
      }) do
    with %User{} = follower <- User.get_cached_by_nickname(follower_nick),
         %User{} = followed <- User.get_cached_by_nickname(followed_nick) do
      User.unfollow(follower, followed)

      ModerationLog.insert_log(%{
        actor: admin,
        followed: followed,
        follower: follower,
        action: "unfollow"
      })
    end

    json(conn, "ok")
  end

  def users_create(%{assigns: %{user: admin}} = conn, %{"users" => users}) do
    changesets =
      Enum.map(users, fn %{"nickname" => nickname, "email" => email, "password" => password} ->
        user_data = %{
          nickname: nickname,
          name: nickname,
          email: email,
          password: password,
          password_confirmation: password,
          bio: "."
        }

        User.register_changeset(%User{}, user_data, need_confirmation: false)
      end)
      |> Enum.reduce(Ecto.Multi.new(), fn changeset, multi ->
        Ecto.Multi.insert(multi, Ecto.UUID.generate(), changeset)
      end)

    case Pleroma.Repo.transaction(changesets) do
      {:ok, users} ->
        res =
          users
          |> Map.values()
          |> Enum.map(fn user ->
            {:ok, user} = User.post_register_action(user)

            user
          end)
          |> Enum.map(&AccountView.render("created.json", %{user: &1}))

        ModerationLog.insert_log(%{
          actor: admin,
          subjects: Map.values(users),
          action: "create"
        })

        json(conn, res)

      {:error, id, changeset, _} ->
        res =
          Enum.map(changesets.operations, fn
            {current_id, {:changeset, _current_changeset, _}} when current_id == id ->
              AccountView.render("create-error.json", %{changeset: changeset})

            {_, {:changeset, current_changeset, _}} ->
              AccountView.render("create-error.json", %{changeset: current_changeset})
          end)

        conn
        |> put_status(:conflict)
        |> json(res)
    end
  end

  def user_show(%{assigns: %{user: admin}} = conn, %{"nickname" => nickname}) do
    with %User{} = user <- User.get_cached_by_nickname_or_id(nickname, for: admin) do
      conn
      |> put_view(AccountView)
      |> render("show.json", %{user: user})
    else
      _ -> {:error, :not_found}
    end
  end

  def list_instance_statuses(conn, %{"instance" => instance} = params) do
    with_reblogs = params["with_reblogs"] == "true" || params["with_reblogs"] == true
    {page, page_size} = page_params(params)

    activities =
      ActivityPub.fetch_statuses(nil, %{
        instance: instance,
        limit: page_size,
        offset: (page - 1) * page_size,
        exclude_reblogs: not with_reblogs
      })

    conn
    |> put_view(AdminAPI.StatusView)
    |> render("index.json", %{activities: activities, as: :activity})
  end

  def list_user_statuses(%{assigns: %{user: admin}} = conn, %{"nickname" => nickname} = params) do
    with_reblogs = params["with_reblogs"] == "true" || params["with_reblogs"] == true
    godmode = params["godmode"] == "true" || params["godmode"] == true

    with %User{} = user <- User.get_cached_by_nickname_or_id(nickname, for: admin) do
      {_, page_size} = page_params(params)

      activities =
        ActivityPub.fetch_user_activities(user, nil, %{
          limit: page_size,
          godmode: godmode,
          exclude_reblogs: not with_reblogs
        })

      conn
      |> put_view(AdminAPI.StatusView)
      |> render("index.json", %{activities: activities, as: :activity})
    else
      _ -> {:error, :not_found}
    end
  end

  def list_user_chats(%{assigns: %{user: admin}} = conn, %{"nickname" => nickname} = _params) do
    with %User{id: user_id} <- User.get_cached_by_nickname_or_id(nickname, for: admin) do
      chats =
        Pleroma.Chat.for_user_query(user_id)
        |> Pleroma.Repo.all()

      conn
      |> put_view(AdminAPI.ChatView)
      |> render("index.json", chats: chats)
    else
      _ -> {:error, :not_found}
    end
  end

  def user_toggle_activation(%{assigns: %{user: admin}} = conn, %{"nickname" => nickname}) do
    user = User.get_cached_by_nickname(nickname)

    {:ok, updated_user} = User.deactivate(user, !user.deactivated)

    action = if user.deactivated, do: "activate", else: "deactivate"

    ModerationLog.insert_log(%{
      actor: admin,
      subject: [user],
      action: action
    })

    conn
    |> put_view(AccountView)
    |> render("show.json", %{user: updated_user})
  end

  def user_activate(%{assigns: %{user: admin}} = conn, %{"nicknames" => nicknames}) do
    users = Enum.map(nicknames, &User.get_cached_by_nickname/1)
    {:ok, updated_users} = User.deactivate(users, false)

    ModerationLog.insert_log(%{
      actor: admin,
      subject: users,
      action: "activate"
    })

    conn
    |> put_view(AccountView)
    |> render("index.json", %{users: Keyword.values(updated_users)})
  end

  def user_deactivate(%{assigns: %{user: admin}} = conn, %{"nicknames" => nicknames}) do
    users = Enum.map(nicknames, &User.get_cached_by_nickname/1)
    {:ok, updated_users} = User.deactivate(users, true)

    ModerationLog.insert_log(%{
      actor: admin,
      subject: users,
      action: "deactivate"
    })

    conn
    |> put_view(AccountView)
    |> render("index.json", %{users: Keyword.values(updated_users)})
  end

  def user_approve(%{assigns: %{user: admin}} = conn, %{"nicknames" => nicknames}) do
    users = Enum.map(nicknames, &User.get_cached_by_nickname/1)
    {:ok, updated_users} = User.approve(users)

    ModerationLog.insert_log(%{
      actor: admin,
      subject: users,
      action: "approve"
    })

    conn
    |> put_view(AccountView)
    |> render("index.json", %{users: updated_users})
  end

  def tag_users(%{assigns: %{user: admin}} = conn, %{"nicknames" => nicknames, "tags" => tags}) do
    with {:ok, _} <- User.tag(nicknames, tags) do
      ModerationLog.insert_log(%{
        actor: admin,
        nicknames: nicknames,
        tags: tags,
        action: "tag"
      })

      json_response(conn, :no_content, "")
    end
  end

  def untag_users(%{assigns: %{user: admin}} = conn, %{"nicknames" => nicknames, "tags" => tags}) do
    with {:ok, _} <- User.untag(nicknames, tags) do
      ModerationLog.insert_log(%{
        actor: admin,
        nicknames: nicknames,
        tags: tags,
        action: "untag"
      })

      json_response(conn, :no_content, "")
    end
  end

  def list_users(conn, params) do
    {page, page_size} = page_params(params)
    filters = maybe_parse_filters(params["filters"])

    search_params = %{
      query: params["query"],
      page: page,
      page_size: page_size,
      tags: params["tags"],
      name: params["name"],
      email: params["email"]
    }

    with {:ok, users, count} <- Search.user(Map.merge(search_params, filters)) do
      json(
        conn,
        AccountView.render("index.json",
          users: users,
          count: count,
          page_size: page_size
        )
      )
    end
  end

  @filters ~w(local external active deactivated need_approval is_admin is_moderator)

  @spec maybe_parse_filters(String.t()) :: %{required(String.t()) => true} | %{}
  defp maybe_parse_filters(filters) when is_nil(filters) or filters == "", do: %{}

  defp maybe_parse_filters(filters) do
    filters
    |> String.split(",")
    |> Enum.filter(&Enum.member?(@filters, &1))
    |> Map.new(&{String.to_existing_atom(&1), true})
  end

  def right_add_multiple(%{assigns: %{user: admin}} = conn, %{
        "permission_group" => permission_group,
        "nicknames" => nicknames
      })
      when permission_group in ["moderator", "admin"] do
    update = %{:"is_#{permission_group}" => true}

    users = nicknames |> Enum.map(&User.get_cached_by_nickname/1)

    for u <- users, do: User.admin_api_update(u, update)

    ModerationLog.insert_log(%{
      action: "grant",
      actor: admin,
      subject: users,
      permission: permission_group
    })

    json(conn, update)
  end

  def right_add_multiple(conn, _) do
    render_error(conn, :not_found, "No such permission_group")
  end

  def right_add(%{assigns: %{user: admin}} = conn, %{
        "permission_group" => permission_group,
        "nickname" => nickname
      })
      when permission_group in ["moderator", "admin"] do
    fields = %{:"is_#{permission_group}" => true}

    {:ok, user} =
      nickname
      |> User.get_cached_by_nickname()
      |> User.admin_api_update(fields)

    ModerationLog.insert_log(%{
      action: "grant",
      actor: admin,
      subject: [user],
      permission: permission_group
    })

    json(conn, fields)
  end

  def right_add(conn, _) do
    render_error(conn, :not_found, "No such permission_group")
  end

  def right_get(conn, %{"nickname" => nickname}) do
    user = User.get_cached_by_nickname(nickname)

    conn
    |> json(%{
      is_moderator: user.is_moderator,
      is_admin: user.is_admin
    })
  end

  def right_delete_multiple(
        %{assigns: %{user: %{nickname: admin_nickname} = admin}} = conn,
        %{
          "permission_group" => permission_group,
          "nicknames" => nicknames
        }
      )
      when permission_group in ["moderator", "admin"] do
    with false <- Enum.member?(nicknames, admin_nickname) do
      update = %{:"is_#{permission_group}" => false}

      users = nicknames |> Enum.map(&User.get_cached_by_nickname/1)

      for u <- users, do: User.admin_api_update(u, update)

      ModerationLog.insert_log(%{
        action: "revoke",
        actor: admin,
        subject: users,
        permission: permission_group
      })

      json(conn, update)
    else
      _ -> render_error(conn, :forbidden, "You can't revoke your own admin/moderator status.")
    end
  end

  def right_delete_multiple(conn, _) do
    render_error(conn, :not_found, "No such permission_group")
  end

  def right_delete(
        %{assigns: %{user: admin}} = conn,
        %{
          "permission_group" => permission_group,
          "nickname" => nickname
        }
      )
      when permission_group in ["moderator", "admin"] do
    fields = %{:"is_#{permission_group}" => false}

    {:ok, user} =
      nickname
      |> User.get_cached_by_nickname()
      |> User.admin_api_update(fields)

    ModerationLog.insert_log(%{
      action: "revoke",
      actor: admin,
      subject: [user],
      permission: permission_group
    })

    json(conn, fields)
  end

  def right_delete(%{assigns: %{user: %{nickname: nickname}}} = conn, %{"nickname" => nickname}) do
    render_error(conn, :forbidden, "You can't revoke your own admin status.")
  end

  @doc "Get a password reset token (base64 string) for given nickname"
  def get_password_reset(conn, %{"nickname" => nickname}) do
    (%User{local: true} = user) = User.get_cached_by_nickname(nickname)
    {:ok, token} = Pleroma.PasswordResetToken.create_token(user)

    conn
    |> json(%{
      token: token.token,
      link: Router.Helpers.reset_password_url(Endpoint, :reset, token.token)
    })
  end

  @doc "Force password reset for a given user"
  def force_password_reset(%{assigns: %{user: admin}} = conn, %{"nicknames" => nicknames}) do
    users = nicknames |> Enum.map(&User.get_cached_by_nickname/1)

    Enum.each(users, &User.force_password_reset_async/1)

    ModerationLog.insert_log(%{
      actor: admin,
      subject: users,
      action: "force_password_reset"
    })

    json_response(conn, :no_content, "")
  end

  @doc "Disable mfa for user's account."
  def disable_mfa(conn, %{"nickname" => nickname}) do
    case User.get_by_nickname(nickname) do
      %User{} = user ->
        MFA.disable(user)
        json(conn, nickname)

      _ ->
        {:error, :not_found}
    end
  end

  @doc "Show a given user's credentials"
  def show_user_credentials(%{assigns: %{user: admin}} = conn, %{"nickname" => nickname}) do
    with %User{} = user <- User.get_cached_by_nickname_or_id(nickname, for: admin) do
      conn
      |> put_view(AccountView)
      |> render("credentials.json", %{user: user, for: admin})
    else
      _ -> {:error, :not_found}
    end
  end

  @doc "Updates a given user"
  def update_user_credentials(
        %{assigns: %{user: admin}} = conn,
        %{"nickname" => nickname} = params
      ) do
    with {_, %User{} = user} <- {:user, User.get_cached_by_nickname(nickname)},
         {:ok, _user} <-
           User.update_as_admin(user, params) do
      ModerationLog.insert_log(%{
        actor: admin,
        subject: [user],
        action: "updated_users"
      })

      if params["password"] do
        User.force_password_reset_async(user)
      end

      ModerationLog.insert_log(%{
        actor: admin,
        subject: [user],
        action: "force_password_reset"
      })

      json(conn, %{status: "success"})
    else
      {:error, changeset} ->
        errors = Map.new(changeset.errors, fn {key, {error, _}} -> {key, error} end)

        {:errors, errors}

      _ ->
        {:error, :not_found}
    end
  end

  def list_log(conn, params) do
    {page, page_size} = page_params(params)

    log =
      ModerationLog.get_all(%{
        page: page,
        page_size: page_size,
        start_date: params["start_date"],
        end_date: params["end_date"],
        user_id: params["user_id"],
        search: params["search"]
      })

    conn
    |> put_view(ModerationLogView)
    |> render("index.json", %{log: log})
  end

  def restart(conn, _params) do
    with :ok <- configurable_from_database() do
      Restarter.Pleroma.restart(Config.get(:env), 50)

      json(conn, %{})
    end
  end

  def need_reboot(conn, _params) do
    json(conn, %{need_reboot: Restarter.Pleroma.need_reboot?()})
  end

  defp configurable_from_database do
    if Config.get(:configurable_from_database) do
      :ok
    else
      {:error, "To use this endpoint you need to enable configuration from database."}
    end
  end

  def reload_emoji(conn, _params) do
    Pleroma.Emoji.reload()

    json(conn, "ok")
  end

  def confirm_email(%{assigns: %{user: admin}} = conn, %{"nicknames" => nicknames}) do
    users = Enum.map(nicknames, &User.get_cached_by_nickname/1)

    User.toggle_confirmation(users)

    ModerationLog.insert_log(%{actor: admin, subject: users, action: "confirm_email"})

    json(conn, "")
  end

  def resend_confirmation_email(%{assigns: %{user: admin}} = conn, %{"nicknames" => nicknames}) do
    users =
      Enum.map(nicknames, fn nickname ->
        nickname
        |> User.get_cached_by_nickname()
        |> User.send_confirmation_email()
      end)

    ModerationLog.insert_log(%{actor: admin, subject: users, action: "resend_confirmation_email"})

    json(conn, "")
  end

  def stats(conn, params) do
    counters = Stats.get_status_visibility_count(params["instance"])

    json(conn, %{"status_visibility" => counters})
  end

  def create_backup(%{assigns: %{user: admin}} = conn, %{"nickname" => nickname}) do
    with %User{} = user <- User.get_by_nickname(nickname),
         {:ok, _} <- Pleroma.User.Backup.create(user, admin.id) do
      ModerationLog.insert_log(%{actor: admin, subject: user, action: "create_backup"})

      json(conn, "")
    end
  end

  defp page_params(params) do
    {get_page(params["page"]), get_page_size(params["page_size"])}
  end

  defp get_page(page_string) when is_nil(page_string), do: 1

  defp get_page(page_string) do
    case Integer.parse(page_string) do
      {page, _} -> page
      :error -> 1
    end
  end

  defp get_page_size(page_size_string) when is_nil(page_size_string), do: @users_page_size

  defp get_page_size(page_size_string) do
    case Integer.parse(page_size_string) do
      {page_size, _} -> page_size
      :error -> @users_page_size
    end
  end
end