From 96d251ec3cb224e8e0712fb0083987e38f039d78 Mon Sep 17 00:00:00 2001
From: Gilbert Wong <gilbertwong96@icloud.com>
Date: Tue, 7 Aug 2018 10:27:04 +0800
Subject: [PATCH] Add encode and decode options and test suites

---
 src/emqx_base62.erl        | 24 ++++++++++++++++++------
 src/emqx_guid.erl          |  4 ++--
 test/emqx_base62_SUITE.erl |  7 +++++--
 3 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/src/emqx_base62.erl b/src/emqx_base62.erl
index 0649900c2..690115ec2 100644
--- a/src/emqx_base62.erl
+++ b/src/emqx_base62.erl
@@ -14,8 +14,10 @@
 
 -module(emqx_base62).
 
--export([encode/1, decode/1]).
-
+-export([encode/1,
+         encode/2,
+         decode/1,
+         decode/2]).
 
 %% @doc Encode any data to base62 binary
 -spec encode(string()
@@ -28,18 +30,23 @@ encode(S) when is_list(S)->
 encode(B) when is_binary(B) ->
     encode(B, <<>>).
 
+%% encode(D, string) ->
+%%     binary_to_list(encode(D)).
+
 %% @doc Decode base62 binary to origin data binary
 decode(L) when is_list(L) ->
     decode(list_to_binary(L));
 decode(B) when is_binary(B) ->
     decode(B, <<>>).
 
-%% encode_base62(<<H:24, Rest/binary>>, Acc) ->
-%%     encode_byte_group(H, Acc);
-%% encode_base62(<<H:16, Rest/binary>>, Acc) ->
-%%     encode_byte_group(H, Acc);
 
 
+%%====================================================================
+%% Internal functions
+%%====================================================================
+
+encode(D, string) ->
+    binary_to_list(encode(D));
 encode(<<Index1:6, Index2:6, Index3:6, Index4:6, Rest/binary>>, Acc) ->
     CharList = [encode_char(Index1), encode_char(Index2), encode_char(Index3), encode_char(Index4)],
     NewAcc = <<Acc/binary,(iolist_to_binary(CharList))/binary>>,
@@ -55,6 +62,10 @@ encode(<<Index1:6, Index2:2>>, Acc) ->
 encode(<<>>, Acc) ->
     Acc.
 
+decode(D, integer) ->
+    binary_to_integer(decode(D));
+decode(D, string) ->
+    binary_to_list(decode(D));
 decode(<<Head:8, Rest/binary>>, Acc)
   when bit_size(Rest) >= 8->
     case Head == $9 of
@@ -99,3 +110,4 @@ decode_char(I) when I >= $A andalso I =< $Z->
 
 decode_char(9, I) ->
     I + 61 - $A.
+
diff --git a/src/emqx_guid.erl b/src/emqx_guid.erl
index 8fe0c7b6e..fa9139ebd 100644
--- a/src/emqx_guid.erl
+++ b/src/emqx_guid.erl
@@ -126,9 +126,9 @@ from_hexstr(S) ->
     I = list_to_integer(binary_to_list(S), 16), <<I:128>>.
 
 to_base62(<<I:128>>) ->
-    binary_to_list(emqx_base62:encode(I)).
+    emqx_base62:encode(I).
 
 from_base62(S) ->
-    I = binary_to_integer(emqx_base62:decode(S)),
+    I = emqx_base62:decode(S, integer),
     <<I:128>>.
 
diff --git a/test/emqx_base62_SUITE.erl b/test/emqx_base62_SUITE.erl
index cf4bc9756..820c7ec32 100644
--- a/test/emqx_base62_SUITE.erl
+++ b/test/emqx_base62_SUITE.erl
@@ -32,5 +32,8 @@ t_base62_encode(_) ->
     <<"65535">> = ?BASE62:decode(?BASE62:encode(<<"65535">>)),
     <<X:128/unsigned-big-integer>> = emqx_guid:gen(),
     <<Y:128/unsigned-big-integer>> = emqx_guid:gen(),
-    X = erlang:binary_to_integer(?BASE62:decode(?BASE62:encode(X))),
-    Y = erlang:binary_to_integer(?BASE62:decode(?BASE62:encode(Y))).
+    X = ?BASE62:decode(?BASE62:encode(X), integer),
+    Y = ?BASE62:decode(?BASE62:encode(Y), integer),
+    <<"helloworld">> = ?BASE62:decode(?BASE62:encode("helloworld")),
+    "helloworld" = ?BASE62:decode(?BASE62:encode("helloworld", string), string).
+