1 files changed, 84 insertions, 14 deletions
diff --git a/src/rebar_prv_new.erl b/src/rebar_prv_new.erl
index 698b14e..e432371 100644
--- a/src/rebar_prv_new.erl
+++ b/src/rebar_prv_new.erl
@@ -17,28 +17,34 @@
 
 -spec init(rebar_state:t()) -> {ok, rebar_state:t()}.
 init(State) ->
-    State1 = rebar_state:add_provider(State, providers:create([{name, ?PROVIDER},
-                                                               {module, ?MODULE},
-                                                               {bare, false},
-                                                               {deps, ?DEPS},
-                                                               {example, "rebar new <template>"},
-                                                               {short_desc, "Create new project from templates."},
-                                                               {desc, info()},
-                                                               {opts, []}])),
+    Provider = providers:create([
+        {name, ?PROVIDER},
+        {module, ?MODULE},
+        {bare, false},
+        {deps, ?DEPS},
+        {example, "rebar new <template>"},
+        {short_desc, "Create new project from templates."},
+        {desc, info()},
+        {opts, [{force, $f, "force", undefined, "overwrite existing files"}]}
+    ]),
+    State1 = rebar_state:add_provider(State, Provider),
     {ok, State1}.
 
 -spec do(rebar_state:t()) -> {ok, rebar_state:t()} | {error, string()}.
 do(State) ->
     case rebar_state:command_args(State) of
-        [TemplateName] ->
-            Template = list_to_atom(TemplateName),
-            rebar_templater:new(Template, "", State),
+        ["help", TemplateName] ->
+            case lists:keyfind(TemplateName, 1, rebar_templater:list_templates(State)) of
+                false -> io:format("template not found.~n");
+                Term -> show_template(Term)
+            end,
             {ok, State};
-        [TemplateName, DirName] ->
-            Template = list_to_atom(TemplateName),
-            rebar_templater:new(Template, DirName, State),
+        [TemplateName | Opts] ->
+            Force = is_forced(State),
+            ok = rebar_templater:new(TemplateName, parse_opts(Opts), Force, State),
             {ok, State};
         [] ->
+            show_short_templates(rebar_templater:list_templates(State)),
             {ok, State}
     end.
 
@@ -56,3 +62,67 @@ info() ->
       "~n"
       "Valid command line options:~n"
       "  template= [var=foo,...]~n", []).
+
+is_forced(State) ->
+    {Args, _} = rebar_state:command_parsed_args(State),
+    case proplists:get_value(force, Args) of
+        undefined -> false;
+        _ -> true
+    end.
+
+parse_opts([]) -> [];
+parse_opts([Opt|Opts]) -> [parse_first_opt(Opt, "") | parse_opts1(Opts)].
+
+parse_opts1([]) -> [];
+parse_opts1([Opt|Opts]) -> [parse_opt(Opt, "") | parse_opts1(Opts)].
+
+%% If the first argument meets no '=', we got a default 'name' argument
+parse_first_opt("", Acc) -> {name, lists:reverse(Acc)};
+parse_first_opt("="++Rest, Acc) -> parse_opt("="++Rest, Acc);
+parse_first_opt([H|Str], Acc) -> parse_first_opt(Str, [H|Acc]).
+
+%% We convert to atoms dynamically. Horrible in general, but fine in a
+%% build system's templating tool.
+parse_opt("", Acc) -> {list_to_atom(lists:reverse(Acc)), "true"};
+parse_opt("="++Rest, Acc) -> {list_to_atom(lists:reverse(Acc)), Rest};
+parse_opt([H|Str], Acc) -> parse_opt(Str, [H|Acc]).
+
+show_short_templates(List) ->
+    lists:map(fun show_short_template/1, lists:sort(List)).
+
+show_short_template({Name, Type, _Location, Description, _Vars}) ->
+    io:format("~s (~s): ~s~n",
+              [Name,
+               format_type(Type),
+               format_description(Description)]).
+
+show_template({Name, Type, Location, Description, Vars}) ->
+    io:format("~s:~n"
+              "\t~s~n"
+              "\tDescription: ~s~n"
+              "\tVariables:~n~s~n",
+              [Name,
+               format_type(Type, Location),
+               format_description(Description),
+               format_vars(Vars)]).
+
+format_type(escript) -> "built-in";
+format_type(file) -> "custom".
+
+format_type(escript, _) ->
+    "built-in template";
+format_type(file, Loc) ->
+    io_lib:format("custom template (~s)", [Loc]).
+
+format_description(Description) ->
+    case Description of
+        undefined -> "<missing description>";
+        _ -> Description
+    end.
+
+format_vars(Vars) -> [format_var(Var) || Var <- Vars].
+
+format_var({Var, Default}) ->
+    io_lib:format("\t\t~p=~p~n",[Var, Default]);
+format_var({Var, Default, Doc}) ->
+    io_lib:format("\t\t~p=~p (~s)~n", [Var, Default, Doc]).