1 files changed, 71 insertions, 0 deletions
diff --git a/src/rebar_agent.erl b/src/rebar_agent.erl
new file mode 100644
index 0000000..849e67c
--- /dev/null
+++ b/src/rebar_agent.erl
@@ -0,0 +1,71 @@
+-module(rebar_agent).
+-export([start_link/1, do/1, do/2]).
+-export([init/1,
+         handle_call/3, handle_cast/2, handle_info/2,
+         code_change/3, terminate/2]).
+
+-record(state, {state,
+                cwd}).
+
+start_link(State) ->
+    gen_server:start_link({local, ?MODULE}, ?MODULE, State, []).
+
+do(Command) when is_atom(Command) ->
+    gen_server:call(?MODULE, {cmd, Command}, infinity).
+
+do(Namespace, Command) when is_atom(Namespace), is_atom(Command) ->
+    gen_server:call(?MODULE, {cmd, Namespace, Command}, infinity).
+
+init(State0) ->
+    Cwd = file:get_cwd(),
+    State = rebar_state:update_code_paths(State0, default, code:get_path()),
+    {ok, #state{state=State, cwd=Cwd}}.
+
+handle_call({cmd, Command}, _From, State=#state{state=RState, cwd=Cwd}) ->
+    Res = try
+        case file:get_cwd() of
+            Cwd ->
+                case rebar_core:process_command(RState, Command) of
+                    {ok, _} ->
+                        refresh(RState),
+                        ok;
+                    {error, Err} when is_list(Err) ->
+                        refresh(RState),
+                        {error, lists:flatten(Err)};
+                    {error, Err} ->
+                        refresh(RState),
+                        {error, Err}
+                end;
+            _ ->
+                {error, cwd_changed}
+        end
+    catch
+        Type:Reason ->
+            {error, {Type, Reason}}
+    end,
+    {reply, Res, State};
+handle_call({cmd, Namespace, Command}, From, State = #state{state=RState}) ->
+    {reply, Res, _} = handle_call({cmd, Command}, From, State#state{
+        state = rebar_state:namespace(RState, Namespace)
+    }),
+    {reply, Res, 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.
+
+refresh(RState) ->
+    ToRefresh = rebar_state:code_paths(RState, all_deps)
+                %% make sure to never reload self; halt()s the VM
+                -- [filename:dirname(code:which(?MODULE))],
+    rebar_utils:update_code(ToRefresh).