move vanillae ts over here

2023-04-21 18:30:37 -06:00
parent abcd435d01
commit 261846aa7e
31 changed files with 0 additions and 0 deletions
@@ -0,0 +1,236 @@
+%-module(b58).
+%-export([enc/1, dec/1]).
+
+-mode(compile).
+%-spec enc(binary()) -> string().
+%% https://digitalbazaar.github.io/base58-spec/#encode
+
+main([]) ->
+    {ok, Cases} = file:consult("b58_cases_3.eterms"),
+    DoCase =
+        fun(Case) ->
+            spawn(fun() -> test_case(Case) end)
+        end,
+    lists:foreach(DoCase, Cases).
+
+test_case({{encoded, E}, {decoded, D}}) ->
+    EncodeOk = E =:= enc(D),
+    DecodeOk = D =:= dec(E),
+    ok =
+        case EncodeOk of
+            true  -> ok;
+            false -> io:format("===============================~n"
+                               "YOU ARE A FAILURE TO ENCODE~n"
+                               "===============================~n"
+                               "decoded  : ~tw~n"
+                               "expected : ~ts~n"
+                               "actual   : ~ts~n~n",
+                               [D, E, enc(D)])
+        end,
+    ok =
+        case DecodeOk of
+            true  -> ok;
+            false -> io:format("===============================~n"
+                               "YOU ARE A FAILURE TO DECODE~n"
+                               "===============================~n"
+                               "encoded  : ~ts~n"
+                               "expected : ~tw~n"
+                               "actual   : ~tw~n~n",
+                               [E, D, dec(E)])
+        end,
+    ok.
+
+% this was much clearer: https://www.youtube.com/watch?v=GedV3S9X89c
+
+-spec enc(Bytes) -> Base58
+    when Bytes  :: binary(),
+         Base58 :: string().
+
+enc(Bytes) ->
+    % grab leading 0s
+    {NumLeadingZeros, Rest}    = split_zeros(Bytes, 0),
+    NBitsInRest                = bit_size(Rest),
+    <<RestBigNum:NBitsInRest>> = Rest,
+    ZerosBase58                = [$1 || _ <- lists:seq(1, NumLeadingZeros)],
+    RestBase58                 = enc(RestBigNum, []),
+    ZerosBase58 ++ RestBase58.
+
+
+
+-spec split_zeros(Bytes, InitZeros) -> {NumLeadingZeros, Rest}
+    when Bytes           :: binary(),
+         InitZeros       :: integer(),
+         NumLeadingZeros :: binary(),
+         Rest            :: binary().
+
+split_zeros(<<0:8, Rest/binary>>, NumZerosAcc) ->
+    NewNumZerosAcc = NumZerosAcc + 1,
+    split_zeros(Rest, NewNumZerosAcc);
+split_zeros(Rest, NumZerosAcc) ->
+    {NumZerosAcc, Rest}.
+
+
+
+-spec enc(BytesBigNum, Base58Acc) -> Base58
+    when BytesBigNum :: integer(),
+         Base58Acc   :: [0..57],
+         Base58      :: string().
+
+enc(0, Acc) ->
+    lists:map(fun int2char/1, Acc);
+enc(BitNum, Acc) ->
+    Q = BitNum div 58,
+    R = BitNum rem 58,
+    enc(Q, [R | Acc]).
+
+
+
+-spec dec(Base58) -> DecodedBytes
+    when Base58       :: string(),
+         DecodedBytes :: binary().
+
+dec(Str) ->
+    % the number of leading 1s tells us the number of leading zeros
+    {NumLeadingZeros, RestStr} = split_ones(Str, 0),
+    LeadingZeros               = << <<0>> || _ <- lists:seq(1, NumLeadingZeros) >>,
+    RestNs                     = lists:map(fun char2int/1, RestStr),
+    RestBytes                  = dec(RestNs, 0),
+    <<LeadingZeros/binary, RestBytes/binary>>.
+
+split_ones([$1 | Rest], NOnes) ->
+    split_ones(Rest, NOnes + 1);
+split_ones(B58Str, NOnes) ->
+    {NOnes, B58Str}.
+
+
+dec([N | Ns], Acc) ->
+    NewAcc = (Acc*58) + N,
+    dec(Ns, NewAcc);
+dec([], FinalAccN) ->
+    bignum_to_binary_bige(FinalAccN, <<>>).
+
+bignum_to_binary_bige(0, Acc) ->
+    Acc;
+bignum_to_binary_bige(N, Acc) ->
+    Q = N div 256,
+    R = N rem 256,
+    NewAcc = <<R, Acc/binary>>,
+    bignum_to_binary_bige(Q, NewAcc).
+
+int2char( 0) -> $1;
+int2char( 1) -> $2;
+int2char( 2) -> $3;
+int2char( 3) -> $4;
+int2char( 4) -> $5;
+int2char( 5) -> $6;
+int2char( 6) -> $7;
+int2char( 7) -> $8;
+int2char( 8) -> $9;
+int2char( 9) -> $A;
+int2char(10) -> $B;
+int2char(11) -> $C;
+int2char(12) -> $D;
+int2char(13) -> $E;
+int2char(14) -> $F;
+int2char(15) -> $G;
+int2char(16) -> $H;
+int2char(17) -> $J;
+int2char(18) -> $K;
+int2char(19) -> $L;
+int2char(20) -> $M;
+int2char(21) -> $N;
+int2char(22) -> $P;
+int2char(23) -> $Q;
+int2char(24) -> $R;
+int2char(25) -> $S;
+int2char(26) -> $T;
+int2char(27) -> $U;
+int2char(28) -> $V;
+int2char(29) -> $W;
+int2char(30) -> $X;
+int2char(31) -> $Y;
+int2char(32) -> $Z;
+int2char(33) -> $a;
+int2char(34) -> $b;
+int2char(35) -> $c;
+int2char(36) -> $d;
+int2char(37) -> $e;
+int2char(38) -> $f;
+int2char(39) -> $g;
+int2char(40) -> $h;
+int2char(41) -> $i;
+int2char(42) -> $j;
+int2char(43) -> $k;
+int2char(44) -> $m;
+int2char(45) -> $n;
+int2char(46) -> $o;
+int2char(47) -> $p;
+int2char(48) -> $q;
+int2char(49) -> $r;
+int2char(50) -> $s;
+int2char(51) -> $t;
+int2char(52) -> $u;
+int2char(53) -> $v;
+int2char(54) -> $w;
+int2char(55) -> $x;
+int2char(56) -> $y;
+int2char(57) -> $z.
+
+char2int($1) ->  0;
+char2int($2) ->  1;
+char2int($3) ->  2;
+char2int($4) ->  3;
+char2int($5) ->  4;
+char2int($6) ->  5;
+char2int($7) ->  6;
+char2int($8) ->  7;
+char2int($9) ->  8;
+char2int($A) ->  9;
+char2int($B) -> 10;
+char2int($C) -> 11;
+char2int($D) -> 12;
+char2int($E) -> 13;
+char2int($F) -> 14;
+char2int($G) -> 15;
+char2int($H) -> 16;
+char2int($J) -> 17;
+char2int($K) -> 18;
+char2int($L) -> 19;
+char2int($M) -> 20;
+char2int($N) -> 21;
+char2int($P) -> 22;
+char2int($Q) -> 23;
+char2int($R) -> 24;
+char2int($S) -> 25;
+char2int($T) -> 26;
+char2int($U) -> 27;
+char2int($V) -> 28;
+char2int($W) -> 29;
+char2int($X) -> 30;
+char2int($Y) -> 31;
+char2int($Z) -> 32;
+char2int($a) -> 33;
+char2int($b) -> 34;
+char2int($c) -> 35;
+char2int($d) -> 36;
+char2int($e) -> 37;
+char2int($f) -> 38;
+char2int($g) -> 39;
+char2int($h) -> 40;
+char2int($i) -> 41;
+char2int($j) -> 42;
+char2int($k) -> 43;
+char2int($m) -> 44;
+char2int($n) -> 45;
+char2int($o) -> 46;
+char2int($p) -> 47;
+char2int($q) -> 48;
+char2int($r) -> 49;
+char2int($s) -> 50;
+char2int($t) -> 51;
+char2int($u) -> 52;
+char2int($v) -> 53;
+char2int($w) -> 54;
+char2int($x) -> 55;
+char2int($y) -> 56;
+char2int($z) -> 57.