1 files changed, 147 insertions, 0 deletions
diff --git a/src/rebar_resource_v2.erl b/src/rebar_resource_v2.erl
new file mode 100644
index 0000000..f032f6e
--- /dev/null
+++ b/src/rebar_resource_v2.erl
@@ -0,0 +1,147 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
+-module(rebar_resource_v2).
+
+-export([new/3,
+         find_resource_state/2,
+         format_source/1,
+         lock/2,
+         download/3,
+         needs_update/2,
+         make_vsn/3,
+         format_error/1]).
+
+-export_type([resource/0,
+              source/0,
+              type/0,
+              location/0,
+              ref/0,
+              resource_state/0]).
+
+-include("rebar.hrl").
+-include_lib("providers/include/providers.hrl").
+
+-type resource() :: #resource{}.
+-type source() :: {type(), location(), ref()} | {type(), location(), ref(), binary()}.
+-type type() :: atom().
+-type location() :: string().
+-type ref() :: any().
+-type resource_state() :: term().
+
+-callback init(type(), rebar_state:t()) -> {ok, resource()}.
+-callback lock(rebar_app_info:t(), resource_state()) -> source().
+-callback download(file:filename_all(), rebar_app_info:t(), resource_state(), rebar_state:t()) ->
+    ok | {error, any()}.
+-callback needs_update(rebar_app_info:t(), resource_state()) -> boolean().
+-callback make_vsn(rebar_app_info:t(), resource_state()) ->
+    {plain, string()} | {error, string()}.
+
+-spec new(type(), module(), term()) -> resource().
+new(Type, Module, State) ->
+    #resource{type=Type,
+              module=Module,
+              state=State,
+              implementation=?MODULE}.
+
+-spec find_resource(type(), [resource()]) -> {ok, resource()} | {error, not_found}.
+find_resource(Type, Resources) ->
+    case ec_lists:find(fun(#resource{type=T}) -> T =:= Type end, Resources) of
+        error when is_atom(Type) ->
+            case code:which(Type) of
+                non_existing ->
+                    {error, not_found};
+                _ ->
+                    {ok, rebar_resource:new(Type, Type, #{})}
+            end;
+        error ->
+            {error, not_found};
+        {ok, Resource} ->
+            {ok, Resource}
+    end.
+
+find_resource_state(Type, Resources) ->
+    case lists:keyfind(Type, #resource.type, Resources) of
+        false ->            
+            {error, not_found};
+        #resource{state=State} ->
+            State
+    end.
+
+format_source({pkg, Name, Vsn, _Hash, _}) -> {pkg, Name, Vsn};
+format_source(Source) -> Source.
+
+lock(AppInfo, State) ->
+    resource_run(lock, rebar_app_info:source(AppInfo), [AppInfo], State).
+
+resource_run(Function, Source, Args, State) ->
+    Resources = rebar_state:resources(State),
+    case get_resource_type(Source, Resources) of
+        {ok, #resource{type=_,
+                       module=Module,
+                       state=ResourceState,
+                       implementation=?MODULE}} ->
+            erlang:apply(Module, Function, Args++[ResourceState]);
+        {ok, #resource{type=_,
+                       module=Module,
+                       state=_,
+                       implementation=rebar_resource}} ->
+            erlang:apply(rebar_resource, Function, [Module | Args])
+    end.
+
+download(TmpDir, AppInfo, State) ->
+    resource_run(download, rebar_app_info:source(AppInfo), [TmpDir, AppInfo, State], State).
+
+needs_update(AppInfo, State) ->
+    resource_run(needs_update, rebar_app_info:source(AppInfo), [AppInfo], State).
+
+%% this is a special case since it is used for project apps as well, not just deps
+make_vsn(AppInfo, VcsType, State) ->
+    Resources = rebar_state:resources(State),
+    case is_resource_type(VcsType, Resources) of
+        true ->
+            case find_resource(VcsType, Resources) of
+                {ok, #resource{type=_,
+                               module=Module,
+                               state=ResourceState,
+                               implementation=?MODULE}} ->
+                    Module:make_vsn(AppInfo, ResourceState);
+                {ok, #resource{type=_,
+                               module=Module,
+                               state=_,
+                               implementation=rebar_resource}} ->
+                    rebar_resource:make_vsn(Module, AppInfo)
+            end;
+        false ->
+            unknown
+    end.
+
+format_error({no_resource, Location, Type}) ->
+    io_lib:format("Cannot handle dependency ~ts.~n"
+                  "     No module found for resource type ~p.", [Location, Type]);
+format_error({no_resource, Source}) ->
+    io_lib:format("Cannot handle dependency ~ts.~n"
+                  "     No module found for unknown resource type.", [Source]).
+
+is_resource_type(Type, Resources) ->
+    lists:any(fun(#resource{type=T}) -> T =:= Type end, Resources).
+
+-spec get_resource_type(term(), [resource()]) -> {ok, resource()}.
+get_resource_type({Type, Location}, Resources) ->
+    get_resource(Type, Location, Resources);
+get_resource_type({Type, Location, _}, Resources) ->
+    get_resource(Type, Location, Resources);
+get_resource_type({Type, _, _, Location}, Resources) ->
+    get_resource(Type, Location, Resources);
+get_resource_type(Location={Type, _, _, _, _}, Resources) ->
+    get_resource(Type, Location, Resources);
+get_resource_type(Source, _) ->
+    throw(?PRV_ERROR({no_resource, Source})).
+
+-spec get_resource(type(), term(), [resource()]) -> {ok, resource()}.
+get_resource(Type, Location, Resources) ->
+    case find_resource(Type, Resources) of
+        {error, not_found} ->
+            throw(?PRV_ERROR({no_resource, Location, Type}));
+        {ok, Resource} ->
+            {ok, Resource}
+    end.