EventHubBack/src/handlers/handler_calendars.erl

%%%-------------------------------------------------------------------
%%% @doc Обработчик маршрута `/v1/calendars`.
%%%
%%% POST – создание нового календаря (требуется подписка для commercial).
%%% GET  – получение списка календарей пользователя.
%%% @end
%%%-------------------------------------------------------------------
-module(handler_calendars).
-behaviour(cowboy_handler).

-export([init/2]).
-export([trails/0]).

-include("records.hrl").

%%% cowboy_handler callback
-spec init(cowboy_req:req(), any()) -> {ok, cowboy_req:req(), any()}.
init(Req0, _State) ->
  case cowboy_req:method(Req0) of
    <<"POST">> -> create_calendar(Req0);
    <<"GET">>  -> list_calendars(Req0);
    _          -> handler_utils:send_error(Req0, 405, <<"Method not allowed">>)
  end.

%%% Swagger metadata
-spec trails() -> [map()].
trails() ->
  [
    #{  % POST
      path        => <<"/v1/calendars">>,
      method      => <<"POST">>,
      description => <<"Create a new calendar">>,
      tags        => [<<"Calendars">>],
      requestBody => #{
        required => true,
        content  => #{<<"application/json">> => #{schema => calendar_create_schema()}}
      },
      responses => #{
        201 => #{description => <<"Calendar created">>},
        400 => #{description => <<"Missing required fields or invalid JSON">>},
        402 => #{description => <<"Subscription required for commercial calendar">>},
        403 => #{description => <<"User account is not active">>}
      }
    },
    #{  % GET
      path        => <<"/v1/calendars">>,
      method      => <<"GET">>,
      description => <<"List calendars of current user">>,
      tags        => [<<"Calendars">>],
      responses => #{
        200 => #{
          description => <<"Array of calendars">>,
          content => #{<<"application/json">> => #{schema => #{
            type  => array,
            items => calendar_schema()
          }}}
        }
      }
    }
  ].

-spec calendar_schema() -> map().
calendar_schema() ->
  #{
    type       => object,
    properties => #{
      id             => #{type => string},
      owner_id       => #{type => string},
      title          => #{type => string},
      description    => #{type => string},
      short_name     => #{type => string, nullable => true},
      category       => #{type => string, nullable => true},
      color          => #{type => string, nullable => true},
      image_url      => #{type => string, nullable => true},
      settings       => #{type => object, nullable => true},
      tags           => #{type => array, items => #{type => string}},
      type           => #{type => string, enum => [<<"personal">>, <<"commercial">>]},
      confirmation   => #{type => string, description => <<"auto, manual, or {timeout, N}">>},
      rating_avg     => #{type => number, format => float},
      rating_count   => #{type => integer},
      status         => #{type => string, enum => [<<"active">>, <<"frozen">>, <<"deleted">>]},
      reason         => #{type => string, nullable => true},
      created_at     => #{type => string, format => <<"date-time">>},
      updated_at     => #{type => string, format => <<"date-time">>}
    }
  }.

-spec calendar_create_schema() -> map().
calendar_create_schema() ->
  #{
    type       => object,
    required   => [<<"title">>],
    properties => #{
      title        => #{type => string},
      description  => #{type => string},
      confirmation => #{type => string, description => <<"auto, manual, or {timeout, N}">>},
      tags         => #{type => array, items => #{type => string}},
      type         => #{type => string, enum => [<<"personal">>, <<"commercial">>]}
    }
  }.

%%%===================================================================
%%% HTTP-методы
%%%===================================================================

%% @doc POST /v1/calendars — создание календаря.
-spec create_calendar(cowboy_req:req()) -> {ok, binary(), cowboy_req:req()}.
create_calendar(Req) ->
  case handler_utils:auth_user(Req) of
    {ok, UserId, Req1} ->
      {ok, Body, Req2} = cowboy_req:read_body(Req1),
      try jsx:decode(Body, [return_maps]) of
        Decoded when is_map(Decoded) ->
          case Decoded of
            #{<<"title">> := Title} ->
              Description  = maps:get(<<"description">>, Decoded, <<"">>),
              Confirmation = parse_confirmation(maps:get(<<"confirmation">>, Decoded, <<"manual">>)),
              Tags         = maps:get(<<"tags">>, Decoded, []),
              Type         = parse_type(maps:get(<<"type">>, Decoded, <<"personal">>)),
              case Type of
                commercial ->
                  case logic_subscription:can_create_commercial_calendar(UserId) of
                    true  -> ok;
                    false ->
                      handler_utils:send_error(Req2, 402, <<"Subscription required for commercial calendar">>),
                      throw(stop)
                  end;
                personal -> ok
              end,
              case logic_calendar:create_calendar(UserId, Title, Description, Confirmation) of
                {ok, Calendar} ->
                  Updates = [{tags, Tags}, {type, Type}],
                  core_calendar:update(Calendar#calendar.id, Updates),
                  {ok, Updated} = core_calendar:get_by_id(Calendar#calendar.id),
                  Response = calendar_to_json(Updated),
                  handler_utils:send_json(Req2, 201, Response);
                {error, user_inactive} ->
                  handler_utils:send_error(Req2, 403, <<"User account is not active">>);
                {error, {content_banned, _Words}} ->
                  handler_utils:send_error(Req2, 400, <<"Content contains banned words">>);
                {error, _} ->
                  handler_utils:send_error(Req2, 500, <<"Internal server error">>)
              end;
            _ ->
              handler_utils:send_error(Req2, 400, <<"Missing required field: title">>)
          end;
        _ ->
          handler_utils:send_error(Req2, 400, <<"Invalid JSON">>)
      catch
        throw:stop -> ok;
        _:_ -> handler_utils:send_error(Req2, 400, <<"Invalid JSON format">>)
      end;
    {error, Code, Message, Req1} ->
      handler_utils:send_error(Req1, Code, Message)
  end.

%% @doc GET /v1/calendars — список календарей пользователя.
-spec list_calendars(cowboy_req:req()) -> {ok, binary(), cowboy_req:req()}.
list_calendars(Req) ->
  case handler_utils:auth_user(Req) of
    {ok, UserId, Req1} ->
      case logic_calendar:list_calendars(UserId) of
        {ok, Calendars} ->
          Response = [calendar_to_json(C) || C <- Calendars],
          handler_utils:send_json(Req1, 200, Response);
        {error, _} ->
          handler_utils:send_error(Req1, 500, <<"Internal server error">>)
      end;
    {error, Code, Message, Req1} ->
      handler_utils:send_error(Req1, Code, Message)
  end.

%%%===================================================================
%%% Внутренние функции
%%%===================================================================

-spec calendar_to_json(#calendar{}) -> map().
calendar_to_json(Calendar) ->
  Base = handler_utils:calendar_to_json(Calendar),
  Base#{confirmation => confirmation_to_json(Calendar#calendar.confirmation)}.

-spec confirmation_to_json(auto | manual | {timeout, integer()}) -> binary() | map().
confirmation_to_json(auto)          -> <<"auto">>;
confirmation_to_json(manual)        -> <<"manual">>;
confirmation_to_json({timeout, N})  -> #{<<"timeout">> => N}.

-spec parse_confirmation(binary() | map()) -> auto | manual | {timeout, integer()}.
parse_confirmation(<<"auto">>)                -> auto;
parse_confirmation(<<"manual">>)              -> manual;
parse_confirmation(#{<<"timeout">> := N}) when is_integer(N), N > 0 -> {timeout, N};
parse_confirmation(_)                         -> manual.

-spec parse_type(binary()) -> personal | commercial.
parse_type(<<"personal">>)   -> personal;
parse_type(<<"commercial">>) -> commercial;
parse_type(_)                -> personal.