Packages

base32_clockwork

2023.1.0
2023.1.0 2021.3.0 2021.2.0

Clockwork Base32

Current section

Files

Jump to
Readme
3 Versions
0 Dependencies
Dependants
Files
Activity
base32_clockwork src base32_clockwork.erl
Raw

src/base32_clockwork.erl 

-module(base32_clockwork).



-export([encode/1, decode/1]).



-import(base32_utils, [rev_bits_list_to_binary/1, bits_list_size/1]).





-spec encode(binary()) -> binary().

encode(Data) ->

    encode0(Data, []).





encode0(<<>>, Accu) ->

    list_to_binary(lists:reverse(Accu));

encode0(<<Bits:5, Next/bitstring>>, Accu) ->

    encode0(Next, [symbol(Bits) | Accu]);

encode0(<<Bits:4, Next/bitstring>>, Accu) ->

    encode0(Next, [symbol(Bits bsl 1) | Accu]);

encode0(<<Bits:3, Next/bitstring>>, Accu) ->

    encode0(Next, [symbol(Bits bsl 2) | Accu]);

encode0(<<Bits:2, Next/bitstring>>, Accu) ->

    encode0(Next, [symbol(Bits bsl 3) | Accu]);

encode0(<<Bits:1, Next/bitstring>>, Accu) ->

    encode0(Next, [symbol(Bits bsl 4) | Accu]).





symbol(0) -> $0;

symbol(1) -> $1;

symbol(2) -> $2;

symbol(3) -> $3;

symbol(4) -> $4;

symbol(5) -> $5;

symbol(6) -> $6;

symbol(7) -> $7;

symbol(8) -> $8;

symbol(9) -> $9;

symbol(10) -> $A;

symbol(11) -> $B;

symbol(12) -> $C;

symbol(13) -> $D;

symbol(14) -> $E;

symbol(15) -> $F;

symbol(16) -> $G;

symbol(17) -> $H;

symbol(18) -> $J;

symbol(19) -> $K;

symbol(20) -> $M;

symbol(21) -> $N;

symbol(22) -> $P;

symbol(23) -> $Q;

symbol(24) -> $R;

symbol(25) -> $S;

symbol(26) -> $T;

symbol(27) -> $V;

symbol(28) -> $W;

symbol(29) -> $X;

symbol(30) -> $Y;

symbol(31) -> $Z.





-spec decode(binary()) -> {ok, binary()} | {error, atom()}.

decode(Data) ->

    decode0(Data, []).





decode0(<<>>, []) ->

    {ok, <<>>};

decode0(<<>>, Accu = [Last | Prev]) ->

    Size = bits_list_size(Accu),

    Last1 = case Size rem 8 of

                0 ->

                    Last;

                PaddingSize ->

                    BodySize = 5 - PaddingSize,

                    <<Last2:BodySize/bitstring, _/bitstring>> = Last,

                    Last2

            end,

    {ok, rev_bits_list_to_binary([Last1 | Prev])};

decode0(<<_:8>>, []) ->

    {error, invalid_size};

decode0(<<"0", Next/binary>>, Accu) ->

    decode0(Next, [<<0:5>> | Accu]);

decode0(<<"O", Next/binary>>, Accu) ->

    decode0(Next, [<<0:5>> | Accu]);

decode0(<<"o", Next/binary>>, Accu) ->

    decode0(Next, [<<0:5>> | Accu]);

decode0(<<"1", Next/binary>>, Accu) ->

    decode0(Next, [<<1:5>> | Accu]);

decode0(<<"I", Next/binary>>, Accu) ->

    decode0(Next, [<<1:5>> | Accu]);

decode0(<<"i", Next/binary>>, Accu) ->

    decode0(Next, [<<1:5>> | Accu]);

decode0(<<"L", Next/binary>>, Accu) ->

    decode0(Next, [<<1:5>> | Accu]);

decode0(<<"l", Next/binary>>, Accu) ->

    decode0(Next, [<<1:5>> | Accu]);

decode0(<<"2", Next/binary>>, Accu) ->

    decode0(Next, [<<2:5>> | Accu]);

decode0(<<"3", Next/binary>>, Accu) ->

    decode0(Next, [<<3:5>> | Accu]);

decode0(<<"4", Next/binary>>, Accu) ->

    decode0(Next, [<<4:5>> | Accu]);

decode0(<<"5", Next/binary>>, Accu) ->

    decode0(Next, [<<5:5>> | Accu]);

decode0(<<"6", Next/binary>>, Accu) ->

    decode0(Next, [<<6:5>> | Accu]);

decode0(<<"7", Next/binary>>, Accu) ->

    decode0(Next, [<<7:5>> | Accu]);

decode0(<<"8", Next/binary>>, Accu) ->

    decode0(Next, [<<8:5>> | Accu]);

decode0(<<"9", Next/binary>>, Accu) ->

    decode0(Next, [<<9:5>> | Accu]);

decode0(<<"A", Next/binary>>, Accu) ->

    decode0(Next, [<<10:5>> | Accu]);

decode0(<<"a", Next/binary>>, Accu) ->

    decode0(Next, [<<10:5>> | Accu]);

decode0(<<"B", Next/binary>>, Accu) ->

    decode0(Next, [<<11:5>> | Accu]);

decode0(<<"b", Next/binary>>, Accu) ->

    decode0(Next, [<<11:5>> | Accu]);

decode0(<<"C", Next/binary>>, Accu) ->

    decode0(Next, [<<12:5>> | Accu]);

decode0(<<"c", Next/binary>>, Accu) ->

    decode0(Next, [<<12:5>> | Accu]);

decode0(<<"D", Next/binary>>, Accu) ->

    decode0(Next, [<<13:5>> | Accu]);

decode0(<<"d", Next/binary>>, Accu) ->

    decode0(Next, [<<13:5>> | Accu]);

decode0(<<"E", Next/binary>>, Accu) ->

    decode0(Next, [<<14:5>> | Accu]);

decode0(<<"e", Next/binary>>, Accu) ->

    decode0(Next, [<<14:5>> | Accu]);

decode0(<<"F", Next/binary>>, Accu) ->

    decode0(Next, [<<15:5>> | Accu]);

decode0(<<"f", Next/binary>>, Accu) ->

    decode0(Next, [<<15:5>> | Accu]);

decode0(<<"G", Next/binary>>, Accu) ->

    decode0(Next, [<<16:5>> | Accu]);

decode0(<<"g", Next/binary>>, Accu) ->

    decode0(Next, [<<16:5>> | Accu]);

decode0(<<"H", Next/binary>>, Accu) ->

    decode0(Next, [<<17:5>> | Accu]);

decode0(<<"h", Next/binary>>, Accu) ->

    decode0(Next, [<<17:5>> | Accu]);

decode0(<<"J", Next/binary>>, Accu) ->

    decode0(Next, [<<18:5>> | Accu]);

decode0(<<"j", Next/binary>>, Accu) ->

    decode0(Next, [<<18:5>> | Accu]);

decode0(<<"K", Next/binary>>, Accu) ->

    decode0(Next, [<<19:5>> | Accu]);

decode0(<<"k", Next/binary>>, Accu) ->

    decode0(Next, [<<19:5>> | Accu]);

decode0(<<"M", Next/binary>>, Accu) ->

    decode0(Next, [<<20:5>> | Accu]);

decode0(<<"m", Next/binary>>, Accu) ->

    decode0(Next, [<<20:5>> | Accu]);

decode0(<<"N", Next/binary>>, Accu) ->

    decode0(Next, [<<21:5>> | Accu]);

decode0(<<"n", Next/binary>>, Accu) ->

    decode0(Next, [<<21:5>> | Accu]);

decode0(<<"P", Next/binary>>, Accu) ->

    decode0(Next, [<<22:5>> | Accu]);

decode0(<<"p", Next/binary>>, Accu) ->

    decode0(Next, [<<22:5>> | Accu]);

decode0(<<"Q", Next/binary>>, Accu) ->

    decode0(Next, [<<23:5>> | Accu]);

decode0(<<"q", Next/binary>>, Accu) ->

    decode0(Next, [<<23:5>> | Accu]);

decode0(<<"R", Next/binary>>, Accu) ->

    decode0(Next, [<<24:5>> | Accu]);

decode0(<<"r", Next/binary>>, Accu) ->

    decode0(Next, [<<24:5>> | Accu]);

decode0(<<"S", Next/binary>>, Accu) ->

    decode0(Next, [<<25:5>> | Accu]);

decode0(<<"s", Next/binary>>, Accu) ->

    decode0(Next, [<<25:5>> | Accu]);

decode0(<<"T", Next/binary>>, Accu) ->

    decode0(Next, [<<26:5>> | Accu]);

decode0(<<"t", Next/binary>>, Accu) ->

    decode0(Next, [<<26:5>> | Accu]);

decode0(<<"V", Next/binary>>, Accu) ->

    decode0(Next, [<<27:5>> | Accu]);

decode0(<<"v", Next/binary>>, Accu) ->

    decode0(Next, [<<27:5>> | Accu]);

decode0(<<"W", Next/binary>>, Accu) ->

    decode0(Next, [<<28:5>> | Accu]);

decode0(<<"w", Next/binary>>, Accu) ->

    decode0(Next, [<<28:5>> | Accu]);

decode0(<<"X", Next/binary>>, Accu) ->

    decode0(Next, [<<29:5>> | Accu]);

decode0(<<"x", Next/binary>>, Accu) ->

    decode0(Next, [<<29:5>> | Accu]);

decode0(<<"Y", Next/binary>>, Accu) ->

    decode0(Next, [<<30:5>> | Accu]);

decode0(<<"y", Next/binary>>, Accu) ->

    decode0(Next, [<<30:5>> | Accu]);

decode0(<<"Z", Next/binary>>, Accu) ->

    decode0(Next, [<<31:5>> | Accu]);

decode0(<<"z", Next/binary>>, Accu) ->

    decode0(Next, [<<31:5>> | Accu]);

decode0(_, _) ->

    {error, invalid_format}.