-module(mysql_proto_constants).
-compile(export_all).

client_flags() ->
    [{long_password, 1, "new more secure passwords"}
     ,{found_rows, 2, "Found instead of affected rows"}
     ,{long_flag, 4, "Get all column flags"}
     ,{connect_with_db, 8, "One can specify db on connect"}
     ,{no_schema, 16, "Don't allow database.table.column"}
     ,{compress, 32, "Can use compression protocol"}
     ,{odbc, 64, "Odbc client"}
     ,{local_files, 128, "Can use LOAD DATA LOCAL"}
     ,{ignore_space, 256, "Ignore spaces before '('"}
     ,{protocol_41, 512, "New 4.1 protocol" }
     ,{interactive, 1024, "This is an interactive client"}
     ,{ssl, 2048, "Switch to SSL after handshake"}
     ,{ignore_sigpipe, 4096, "IGNORE sigpipes"}
     ,{transactions, 8192, "Client knows about transactions"}
     ,{reserved, 16384, "Old flag for 4.1 protocol "}
     ,{secure_connection, 32768, "New 4.1 authentication"}
     ,{multi_statements, 65536, "Enable/disable multi-stmt support"}
     ,{multi_results, 131072, "Enable/disable multi-results"}
    ].

client_flags(Value) when is_integer(Value) ->
    lists:reverse(flags(Value, client_flags())).

flags(Flags, FlagDefs) when is_integer(Flags) ->
    lists:foldl(fun ({Flag, Pos, _Desc}, Acc)
                    when Flags band Pos =/= 0 ->
                        [Flag | Acc];
                    (_, Acc) -> Acc
                end,
                [],
                FlagDefs).

flag_value(Atom) when is_atom(Atom) ->
	{value, {Atom, Mask, _Desc}} = lists:keysearch(Atom, 1, client_flags()),
	Mask;
flag_value([]) ->
	0;
flag_value([H|T]) ->
  flag_value(H) bor flag_value(T).

flag_value(Flags, FlagDefs) ->
    lists:foldl(fun (Flag, Acc) ->
                        case lists:keysearch(Flag, 1, FlagDefs) of
                            {value, {Flag, Pos, _Desc}} ->
                                Acc bor Pos;
                            false -> Acc
                        end
                end,
                0,
                Flags).