-module(handler_login).
-behaviour(cowboy_handler).
-export([init/2]).

-include("records.hrl").

init(Req0, State) ->
  handle(Req0, State).

handle(Req, _Opts) ->
  case cowboy_req:method(Req) of
    <<"POST">> ->
      case cowboy_req:has_body(Req) of
        true ->
          {ok, Body, Req1} = cowboy_req:read_body(Req),
          case Body of
            <<>> ->
              send_error(Req1, 400, <<"Empty request body">>);
            _ ->
              try jsx:decode(Body, [return_maps]) of
                #{<<"email">> := Email, <<"password">> := Password} ->
                  case eventhub_auth:authenticate_user_request(Req1, Email, Password) of
                    {ok, Token, User} ->
                      {RefreshToken, _ExpiresAt} = eventhub_auth:generate_refresh_token(maps:get(id, User)),
                      core_session:create(maps:get(id, User), RefreshToken),
                      Response = #{
                        user => #{
                          id => maps:get(id, User),
                          email => maps:get(email, User),
                          role => maps:get(role, User)
                        },
                        token => Token,
                        refresh_token => RefreshToken
                      },
                      send_json(Req1, 200, Response);
                    {error, frozen} ->
                      send_error(Req1, 403, <<"Account frozen">>);
                    {error, deleted} ->
                      send_error(Req1, 403, <<"Account deleted">>);
                    {error, _Reason} ->
                      send_error(Req1, 401, <<"Invalid credentials">>)
                  end;
                _ ->
                  send_error(Req1, 400, <<"Missing email or password">>)
              catch
                _:_ -> send_error(Req1, 400, <<"Invalid JSON">>)
              end
          end;
        false ->
          send_error(Req, 400, <<"Missing request body">>)
      end;
    _ ->
      send_error(Req, 405, <<"Method not allowed">>)
  end.

send_json(Req, Status, Data) ->
  Body = jsx:encode(Data),
  cowboy_req:reply(Status, #{
    <<"content-type">> => <<"application/json">>
  }, Body, Req),
  {ok, Body, []}.

send_error(Req, Status, Message) ->
  Body = jsx:encode(#{error => Message}),
  cowboy_req:reply(Status, #{
    <<"content-type">> => <<"application/json">>
  }, Body, Req),
  {ok, Body, []}.