wip

3 files changed, 86 insertions, 0 deletions

diff --git a/learn-you-some-erlang/m8ball/src/m8ball.erl b/learn-you-some-erlang/m8ball/src/m8ball.erl
new file mode 100644
index 0000000..041601b
--- /dev/null
+++ b/learn-you-some-erlang/m8ball/src/m8ball.erl
@@ -0,0 +1,24 @@
+-module(m8ball).
+-behaviour(application).
+-export([start/2, stop/1]).
+-export([ask/1]).
+
+%%%%%%%%%%%%%%%%%
+%%% CALLBACKS %%%
+%%%%%%%%%%%%%%%%%
+
+%% start({failover, Node}, Args) is only called
+%% when a start_phase key is defined.
+start(normal, []) ->
+    m8ball_sup:start_link();
+start({takeover, _OtherNode}, []) ->
+    m8ball_sup:start_link().
+
+stop(_State) ->
+    ok.
+
+%%%%%%%%%%%%%%%%%
+%%% INTERFACE %%%
+%%%%%%%%%%%%%%%%%
+ask(Question) ->
+    m8ball_server:ask(Question).
diff --git a/learn-you-some-erlang/m8ball/src/m8ball_server.erl b/learn-you-some-erlang/m8ball/src/m8ball_server.erl
new file mode 100644
index 0000000..4e821ad
--- /dev/null
+++ b/learn-you-some-erlang/m8ball/src/m8ball_server.erl
@@ -0,0 +1,46 @@
+-module(m8ball_server).
+-behaviour(gen_server).
+-export([start_link/0, stop/0, ask/1]).
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2,
+         code_change/3, terminate/2]).
+
+%%%%%%%%%%%%%%%%%
+%%% INTERFACE %%%
+%%%%%%%%%%%%%%%%%
+start_link() ->
+    gen_server:start_link({global, ?MODULE}, ?MODULE, [], []).
+
+stop() ->
+    gen_server:call({global, ?MODULE}, stop).
+
+ask(_Question) -> % the question doesn't matter!
+    gen_server:call({global, ?MODULE}, question).
+
+%%%%%%%%%%%%%%%%%
+%%% CALLBACKS %%%
+%%%%%%%%%%%%%%%%%
+init([]) ->
+    <<A:32, B:32, C:32>> = crypto:rand_bytes(12),
+    random:seed(A,B,C),
+    {ok, []}.
+
+handle_call(question, _From, State) ->
+    {ok, Answers} = application:get_env(m8ball, answers),
+    Answer = element(random:uniform(tuple_size(Answers)), Answers),
+    {reply, Answer, State};
+handle_call(stop, _From, State) ->
+    {stop, normal, ok, State};
+handle_call(_Call, _From, State) ->
+    {noreply, State}.
+
+handle_cast(_Cast, State) ->
+    {noreply, State}.
+
+handle_info(_Info, State) ->
+    {noreply, State}.
+
+code_change(_OldVsn, State, _Extra) ->
+    {ok, State}.
+
+terminate(_Reason, _State) ->
+    ok.
diff --git a/learn-you-some-erlang/m8ball/src/m8ball_sup.erl b/learn-you-some-erlang/m8ball/src/m8ball_sup.erl
new file mode 100644
index 0000000..ca5e426
--- /dev/null
+++ b/learn-you-some-erlang/m8ball/src/m8ball_sup.erl
@@ -0,0 +1,16 @@
+-module(m8ball_sup).
+-behaviour(supervisor).
+-export([start_link/0, init/1]).
+
+start_link() ->
+    supervisor:start_link({global,?MODULE}, ?MODULE, []).
+
+init([]) ->
+    {ok, {{one_for_one, 1, 10},
+          [{m8ball,
+            {m8ball_server, start_link, []},
+            permanent,
+            5000,
+            worker,
+            [m8ball_server]
+          }]}}.