1 files changed, 60 insertions, 0 deletions
diff --git a/src/battle/game-logic/btl_movement.erl b/src/battle/game-logic/btl_movement.erl
new file mode 100644
index 0000000..87b1806
--- /dev/null
+++ b/src/battle/game-logic/btl_movement.erl
@@ -0,0 +1,60 @@
+-module(btl_movement).
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% TYPES %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% EXPORTS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+-export([cross/4]).
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% LOCAL FUNCTIONS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% EXPORTED FUNCTIONS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+-spec cross
+   (
+      btl_battlemap:type(),
+      list(btl_location:type()),
+      list(btl_direction:enum()),
+      non_neg_integer(),
+      btl_location:type()
+   )
+   -> {btl_location:type(), non_neg_integer()}.
+cross (_Battlemap, _ForbiddenLocations, [], Cost, Location) ->
+   {Location, Cost};
+cross (Battlemap, ForbiddenLocations, [Step|NextSteps], Cost, Location) ->
+   NextLocation = btl_location:apply_direction(Step, Location),
+   NextTileClassID = btl_battlemap:get_tile_class_id(NextLocation, Battlemap),
+   NextTileID = btl_tile:class_id_to_type_id(NextTileClassID),
+   NextTile = btl_tile:from_id(NextTileID),
+   NextCost = (Cost + btl_tile:get_cost(NextTile)),
+   IsForbidden =
+      lists:foldl
+      (
+         fun (ForbiddenLocation, Prev) ->
+            (Prev or (NextLocation == ForbiddenLocation))
+         end,
+         false,
+         ForbiddenLocations
+      ),
+
+   IsForbidden = false,
+
+   cross(Battlemap, ForbiddenLocations, NextSteps, NextCost, NextLocation).
+
+-spec cross
+   (
+      btl_battlemap:type(),
+      list(btl_location:type()),
+      list(btl_direction:enum()),
+      btl_location:type()
+   )
+   -> {btl_location:type(), non_neg_integer()}.
+cross (Battlemap, ForbiddenLocations, Path, Location) ->
+   cross(Battlemap, ForbiddenLocations, Path, 0, Location).