Clears up Battlemap/Navigator.elm

4 files changed, 168 insertions, 107 deletions

diff --git a/client/elm/battlemap/src/Battlemap/Navigator.elm b/client/elm/battlemap/src/Battlemap/Navigator.elm
index 41593c5..79f1f73 100644
--- a/client/elm/battlemap/src/Battlemap/Navigator.elm
+++ b/client/elm/battlemap/src/Battlemap/Navigator.elm
@@ -2,19 +2,16 @@ module Battlemap.Navigator exposing
    (
       Type,
       new_navigator,
-      reset_navigation,
-      go
+      reset_navigation
    )
 
 import Set -- exposing (Set, member, empty, insert, remove)
-import List -- exposing (head, tail)
 
 import Battlemap
 import Battlemap.Direction
 import Battlemap.Location
 import Battlemap.Tile
 
-import Character
 
 type alias Type =
    {
@@ -39,104 +36,3 @@ reset_navigation t =
    {t |
       nav_level = Battlemap.Direction.None
    }
-
-go : (
-      Battlemap.Type ->
-      Type ->
-      Battlemap.Direction.Type ->
-      (List Character.Type) ->
-      (Battlemap.Type, Type)
-   )
-go battlemap nav dir char_list =
-   let
-      next_location = (Battlemap.Location.neighbor nav.current_location dir)
-      is_occupied = (List.any (\c -> (c.location == next_location)) char_list)
-   in
-      if
-      (
-         (not is_occupied)
-         && (nav.remaining_points > 0)
-         && (Battlemap.has_location battlemap next_location)
-         && (nav.current_location /= next_location)
-         &&
-         (not
-            (Set.member
-               (Battlemap.Location.get_ref next_location)
-               nav.visited_locations
-            )
-         )
-      )
-      then
-         (
-            (case
-               (Battlemap.apply_to_tile
-                  battlemap
-                  nav.current_location
-                  (Battlemap.Tile.set_direction dir)
-               )
-               of
-                  Nothing -> battlemap
-                  (Just bmap0) ->
-                     (case
-                        (Battlemap.apply_to_tile
-                           bmap0
-                           next_location
-                           (Battlemap.Tile.set_direction dir)
-                        )
-                     of
-                        Nothing -> battlemap
-                        (Just bmap1) -> bmap1
-                     )
-            ),
-            {nav |
-               current_location = next_location,
-               visited_locations =
-                  (Set.insert
-                     (Battlemap.Location.get_ref nav.current_location)
-                     nav.visited_locations
-                  ),
-               previous_directions = (dir :: nav.previous_directions),
-               remaining_points = (nav.remaining_points - 1)
-            }
-         )
-      else if (not is_occupied)
-      then
-         case
-            (
-               (List.head nav.previous_directions),
-               (List.tail nav.previous_directions)
-            )
-         of
-            (Nothing, _) -> (battlemap, nav)
-            (_ , Nothing) -> (battlemap, nav)
-            ((Just prev_dir), (Just prev_dir_list)) ->
-               if (dir == (Battlemap.Direction.opposite_of prev_dir))
-               then
-                  (
-                     (case
-                        (Battlemap.apply_to_tile
-                           battlemap
-                           nav.current_location
-                           (Battlemap.Tile.set_direction
-                              Battlemap.Direction.None
-                           )
-                        )
-                        of
-                           Nothing -> battlemap
-                           (Just bmap) -> bmap
-                     ),
-                     {nav |
-                        current_location = next_location,
-                        visited_locations =
-                           (Set.remove
-                              (Battlemap.Location.get_ref next_location)
-                              nav.visited_locations
-                           ),
-                        previous_directions = prev_dir_list,
-                        remaining_points = (nav.remaining_points + 1)
-                     }
-                  )
-               else
-                  (battlemap, nav)
-      else
-         (battlemap, nav)
diff --git a/client/elm/battlemap/src/Battlemap/Navigator/Move.elm b/client/elm/battlemap/src/Battlemap/Navigator/Move.elm
new file mode 100644
index 0000000..924f715
--- /dev/null
+++ b/client/elm/battlemap/src/Battlemap/Navigator/Move.elm
@@ -0,0 +1,153 @@
+module Battlemap.Navigator.Move exposing (to)
+
+import Set
+import List
+
+import Battlemap
+import Battlemap.Direction
+import Battlemap.Location
+import Battlemap.Tile
+import Battlemap.Navigator
+
+import Character
+
+import Util.List
+
+can_move_to_new_tile : (
+      Battlemap.Navigator.Type ->
+      Battlemap.Type ->
+      Battlemap.Location.Type ->
+      Bool
+   )
+can_move_to_new_tile nav battlemap next_location =
+   (
+      (nav.remaining_points > 0)
+      && (Battlemap.has_location battlemap next_location)
+      && (nav.current_location /= next_location)
+      &&
+      (not
+         (Set.member
+            (Battlemap.Location.get_ref next_location)
+            nav.visited_locations
+         )
+      )
+   )
+
+battlemap_move_to : (
+      Battlemap.Type ->
+      Battlemap.Location.Type ->
+      Battlemap.Direction.Type ->
+      Battlemap.Location.Type ->
+      Battlemap.Type
+   )
+battlemap_move_to battlemap current_loc dir next_loc =
+   (Battlemap.apply_to_tile_unsafe
+      (Battlemap.apply_to_tile_unsafe
+         battlemap
+         current_loc
+         (Battlemap.Tile.set_direction dir)
+      )
+      next_loc
+      (Battlemap.Tile.set_direction dir)
+   )
+
+navigator_move_to : (
+      Battlemap.Navigator.Type ->
+      Battlemap.Direction.Type ->
+      Battlemap.Location.Type ->
+      Battlemap.Navigator.Type
+   )
+navigator_move_to nav dir next_loc =
+   {nav |
+      current_location = next_loc,
+      visited_locations =
+         (Set.insert
+            (Battlemap.Location.get_ref nav.current_location)
+            nav.visited_locations
+         ),
+      previous_directions = (dir :: nav.previous_directions),
+      remaining_points = (nav.remaining_points - 1)
+   }
+
+battlemap_backtrack : (
+      Battlemap.Type ->
+      Battlemap.Location.Type ->
+      Battlemap.Type
+   )
+battlemap_backtrack battlemap current_loc =
+   (Battlemap.apply_to_tile_unsafe
+      battlemap
+      current_loc
+      (Battlemap.Tile.set_direction
+         Battlemap.Direction.None
+      )
+   )
+
+navigator_backtrack : (
+      Battlemap.Navigator.Type ->
+      Battlemap.Location.Type ->
+      (List Battlemap.Direction.Type) ->
+      Battlemap.Navigator.Type
+   )
+navigator_backtrack nav next_loc prev_dir_tail =
+   {nav |
+      current_location = next_loc,
+      visited_locations =
+         (Set.remove
+            (Battlemap.Location.get_ref next_loc)
+            nav.visited_locations
+         ),
+      previous_directions = prev_dir_tail,
+      remaining_points = (nav.remaining_points + 1)
+   }
+
+to : (
+      Battlemap.Type ->
+      Battlemap.Navigator.Type ->
+      Battlemap.Direction.Type ->
+      (List Character.Type) ->
+      (Battlemap.Type, Battlemap.Navigator.Type)
+   )
+to battlemap nav dir char_list =
+   let
+      next_location = (Battlemap.Location.neighbor nav.current_location dir)
+      is_occupied = (List.any (\c -> (c.location == next_location)) char_list)
+   in
+      if (not is_occupied)
+      then
+         if (can_move_to_new_tile nav battlemap next_location)
+         then
+            (
+               (battlemap_move_to
+                  battlemap
+                  nav.current_location
+                  dir
+                  next_location
+               ),
+               (navigator_move_to
+                  nav
+                  dir
+                  next_location
+               )
+            )
+         else
+            case (Util.List.pop nav.previous_directions) of
+               Nothing -> (battlemap, nav)
+               (Just (head, tail)) ->
+                  if (head == (Battlemap.Direction.opposite_of dir))
+                  then
+                     (
+                        (battlemap_backtrack
+                           battlemap
+                           nav.current_location
+                        ),
+                        (navigator_backtrack
+                           nav
+                           next_location
+                           tail
+                        )
+                     )
+                  else
+                     (battlemap, nav)
+      else
+         (battlemap, nav)
diff --git a/client/elm/battlemap/src/Update/DirectionRequest.elm b/client/elm/battlemap/src/Update/DirectionRequest.elm
index 6f30866..2d8b42c 100644
--- a/client/elm/battlemap/src/Update/DirectionRequest.elm
+++ b/client/elm/battlemap/src/Update/DirectionRequest.elm
@@ -3,7 +3,7 @@ module Update.DirectionRequest exposing (apply_to)
 import Dict
 
 import Battlemap.Direction
-import Battlemap.Navigator
+import Battlemap.Navigator.Move
 
 import Model
 
@@ -15,7 +15,7 @@ apply_to model dir =
       ((Just char_id), (Just nav)) ->
          let
             (new_bmap, new_nav) =
-               (Battlemap.Navigator.go
+               (Battlemap.Navigator.Move.to
                   model.battlemap
                   nav
                   dir
diff --git a/client/elm/battlemap/src/Util/List.elm b/client/elm/battlemap/src/Util/List.elm
new file mode 100644
index 0000000..c4db397
--- /dev/null
+++ b/client/elm/battlemap/src/Util/List.elm
@@ -0,0 +1,12 @@
+module Util.List exposing (pop)
+
+import List
+
+pop : List a -> (Maybe (a, List a))
+pop l =
+   case
+      ((List.head l), (List.tail l))
+   of
+      (Nothing, _) -> Nothing
+      (_ , Nothing) -> Nothing
+      ((Just head), (Just tail)) -> (Just (head, tail))