defmodule Mobilizon.Resources do @moduledoc """ The Resources context. """ alias Ecto.Adapters.SQL alias Ecto.Multi alias Ecto.UUID alias Mobilizon.Actors alias Mobilizon.Actors.Actor alias Mobilizon.Resources.Resource alias Mobilizon.Storage.{Page, Repo} import Ecto.Query require Logger @resource_preloads [:actor, :creator, :children, :parent] @doc """ Returns the list of recent resources for a group """ @spec get_resources_for_group(Actor.t(), integer | nil, integer | nil) :: Page.t() def get_resources_for_group(%Actor{id: group_id}, page \\ nil, limit \\ nil) do Resource |> where(actor_id: ^group_id) |> order_by(desc: :updated_at) |> preload([r], [:actor, :creator]) |> Page.build_page(page, limit) end @doc """ Returns the list of top-level resources for a group """ def get_top_level_resources_for_group(%Actor{id: group_id}, page \\ nil, limit \\ nil) do get_resources_for_folder(%Resource{id: "root_something", actor_id: group_id}, page, limit) end @doc """ Returns the list of resources for a resource folder. """ @spec get_resources_for_folder(Resource.t(), integer | nil, integer | nil) :: Page.t() def get_resources_for_folder(resource, page \\ nil, limit \\ nil) def get_resources_for_folder( %Resource{id: "root_" <> _group_id, actor_id: group_id}, page, limit ) do Resource |> where([r], r.actor_id == ^group_id and is_nil(r.parent_id)) |> order_by(asc: :type) |> preload([r], [:actor, :creator]) |> Page.build_page(page, limit) end def get_resources_for_folder(%Resource{id: resource_id}, page, limit) do Resource |> where([r], r.parent_id == ^resource_id) |> order_by(asc: :type) |> preload([r], [:actor, :creator]) |> Page.build_page(page, limit) end @doc """ Get a resource by it's ID """ @spec get_resource(integer | String.t()) :: Resource.t() | nil def get_resource(nil), do: nil def get_resource(id), do: Repo.get(Resource, id) @spec get_resource_with_preloads(integer | String.t()) :: Resource.t() | nil def get_resource_with_preloads(id) do Resource |> Repo.get(id) |> Repo.preload(@resource_preloads) end @spec get_resource_by_group_and_path_with_preloads(String.t() | integer, String.t()) :: Resource.t() | nil def get_resource_by_group_and_path_with_preloads(group_id, "/") do with {:ok, %Actor{} = group} <- Actors.get_group_by_actor_id(group_id) do %Resource{ actor_id: group_id, id: "root_#{group_id}", actor: group, path: "/", title: "Root" } end end def get_resource_by_group_and_path_with_preloads(group_id, path) do Resource |> Repo.get_by(actor_id: group_id, path: path) |> Repo.preload(@resource_preloads) end @doc """ Get a resource by it's URL """ @spec get_resource_by_url(String.t()) :: Resource.t() | nil def get_resource_by_url(url), do: Repo.get_by(Resource, url: url) @spec get_resource_by_url_with_preloads(String.t()) :: Resource.t() | nil def get_resource_by_url_with_preloads(url) do Resource |> Repo.get_by(url: url) |> Repo.preload(@resource_preloads) end @doc """ Creates a resource. """ @spec create_resource(map) :: {:ok, Resource.t()} | {:error, Ecto.Changeset.t()} def create_resource(attrs \\ %{}) do Multi.new() |> do_find_parent_path(Map.get(attrs, :parent_id)) |> Multi.insert(:insert, fn %{find_parent_path: path} -> Resource.changeset(%Resource{}, Map.put(attrs, :path, "#{path}/#{attrs.title}")) end) |> Repo.transaction() |> case do {:ok, %{insert: %Resource{} = resource}} -> {:ok, resource} {:error, operation, reason, _changes} -> {:error, "Error while inserting resource when #{operation} because of #{inspect(reason)}"} end end @doc """ Updates a resource. Since a resource can be a folder and hold children, we do the following in a transaction: * Get the parent path so that we can reconstruct the path for current resource (if moved or simply renamed) * Update all children with the new parent path * Update the resource path itself """ @spec update_resource(Resource.t(), map) :: {:ok, Resource.t()} | {:error, Ecto.Changeset.t()} def update_resource(%Resource{title: old_title} = resource, attrs) do Multi.new() |> find_parent_path(resource, attrs) |> update_children(resource, attrs) |> Multi.update(:update, fn %{find_parent_path: path} -> title = Map.get(attrs, :title, old_title) Resource.changeset(resource, Map.put(attrs, :path, "#{path}/#{title}")) end) |> Repo.transaction() |> case do {:ok, %{ find_parent_path: _parent_path, update: %Resource{} = resource, update_children: children }} -> resource = Map.put(resource, :children, children) {:ok, resource} # collect errors into record changesets {:error, operation, reason, _changes} -> {:error, "Error while updating resource when #{operation} because of #{inspect(reason)}"} end end @spec find_parent_path(Multi.t(), Resource.t(), map()) :: Multi.t() defp find_parent_path( %Multi{} = multi, %Resource{parent_id: old_parent_id} = _resource, attrs ) do updated_parent_id = Map.get(attrs, :parent_id, old_parent_id) Logger.debug("Finding parent path for updated_parent_id #{inspect(updated_parent_id)}") do_find_parent_path(multi, updated_parent_id) end @spec do_find_parent_path(Multi.t(), String.t() | nil) :: Multi.t() defp do_find_parent_path(%Multi{} = multi, nil), do: Multi.run(multi, :find_parent_path, fn _, _ -> {:ok, ""} end) defp do_find_parent_path(%Multi{} = multi, parent_id) do Multi.run(multi, :find_parent_path, fn _repo, _changes -> case get_resource(parent_id) do %Resource{path: path} = _resource -> {:ok, path} _ -> {:error, :not_found} end end) end @spec update_children(Multi.t(), Resource.t(), map()) :: Multi.t() defp update_children( %Multi{} = multi, %Resource{ id: id, type: :folder, title: old_title, actor_id: actor_id }, attrs ) do title = Map.get(attrs, :title, old_title) Multi.run(multi, :update_children, fn repo, %{find_parent_path: path} -> {:ok, uuid} = UUID.dump(id) {query, params} = {"UPDATE resource SET path = CONCAT($1::text, title) WHERE actor_id = $2 AND parent_id = $3::uuid", ["#{path}/#{title}/", actor_id, uuid]} {:ok, _} = SQL.query( repo, query, params ) children = repo.all(from(r in Resource, where: r.parent_id == ^id)) {:ok, children} end) end defp update_children(multi, _, _), do: Multi.run(multi, :update_children, fn _, _ -> {:ok, ""} end) @doc """ Deletes a resource """ @spec delete_resource(Resource.t()) :: {:ok, Resource.t()} | {:error, Ecto.Changeset.t()} def delete_resource(%Resource{} = resource), do: Repo.delete(resource) end