add stub functions for cpu movement

Signed-off-by: Ryan1729 <[email protected]>

Author: Ryan1729

Extras.elm

@@ -30,3 +30,34 @@ indexOfDefault : List a -> a -> Int
 indexOfDefault lst element =
     indexOfhelper lst element 0
         |> Maybe.withDefault -1
+
+
+
+-- from https://github.com/elm-community/list-extra
+
+
+find : (a -> Bool) -> List a -> Maybe a
+find predicate list =
+    case list of
+        [] ->
+            Nothing
+
+        first :: rest ->
+            if predicate first then
+                Just first
+            else
+                find predicate rest
+
+
+
+-- from https://github.com/elm-community/maybe-extra
+
+
+orElseLazy : (() -> Maybe a) -> Maybe a -> Maybe a
+orElseLazy fma mb =
+    case mb of
+        Nothing ->
+            fma ()
+
+        Just _ ->
+            mb

Update.elm

@@ -3,6 +3,8 @@ module Update exposing (update)
 import Msg exposing (Msg(..))
 import Model exposing (..)
 import Material
+import Extras
+import Random.Pcg as Random exposing (Seed)
 
 
 update : Msg -> Model -> ( Model, Cmd Msg )
@@ -22,7 +24,7 @@ update msg model =
                                 , selected = Nothing
                             }
                     in
-                        if checkForAnyLines newModel then
+                        if checkForAnyLines newModel.board then
                             ( { newModel | turnState = Win }, Cmd.none )
                         else
                             ( newModel, Cmd.none )
@@ -39,26 +41,63 @@ update msg model =
 
 cpuTurn : Model -> Model
 cpuTurn model =
+    case model.selected of
+        Just piece ->
+            case makeCpuMove piece model.board of
+                Just newBoard ->
+                    let
+                        newModel =
+                            { model | board = newBoard }
+                    in
+                        if checkForAnyLines newModel.board then
+                            { newModel | turnState = Loss }
+                        else
+                            newModel
+
+                Nothing ->
+                    model
+
+        Nothing ->
+            model
+
+
+makeCpuMove piece board =
     let
-        newModel =
-            makeCpuMove model
+        moves =
+            getMoves piece board
     in
-        if checkForAnyLines newModel then
-            { newModel | turnState = Loss }
-        else
-            newModel
+        Extras.find (cpuWinningMove board) moves
+            |> Extras.orElseLazy (\() -> Extras.find (nonLosingMove board) moves)
+            |> Extras.orElseLazy (\() -> Random.step (Random.sample moves) (Random.initialSeed 42) |> fst)
+            |> Maybe.map (applyMove board)
+
+
+applyMove : Board -> ( FloorId, SpaceId, Piece ) -> Board
+applyMove board ( floorId, spaceId, Piece shape colour pattern ) =
+    board
+
+
+getMoves : Piece -> Board -> List ( FloorId, SpaceId, Piece )
+getMoves piece board =
+    []
+
+
+cpuWinningMove : Board -> ( FloorId, SpaceId, Piece ) -> Bool
+cpuWinningMove board ( floorId, spaceId, piece ) =
+    False
 
 
-makeCpuMove model =
-    model
+nonLosingMove : Board -> ( FloorId, SpaceId, Piece ) -> Bool
+nonLosingMove board ( floorId, spaceId, piece ) =
+    False
 
 
-checkForAnyLines : Model -> Bool
-checkForAnyLines model =
-    checkMultiFloorLines model.board
-        |> andCheckFloor Top model.board
-        |> andCheckFloor Middle model.board
-        |> andCheckFloor Bottom model.board
+checkForAnyLines : Board -> Bool
+checkForAnyLines board =
+    checkMultiFloorLines board
+        |> andCheckFloor Top board
+        |> andCheckFloor Middle board
+        |> andCheckFloor Bottom board
 
 
 checkMultiFloorLines : Board -> Bool

elm-package.json

@@ -12,6 +12,7 @@
         "elm-lang/core": "4.0.5 <= v < 5.0.0",
         "elm-lang/html": "1.1.0 <= v < 2.0.0",
         "elm-lang/svg": "1.1.1 <= v < 2.0.0",
+        "mgold/elm-random-pcg": "3.0.4 <= v < 4.0.0",
         "robertjlooby/elm-generic-dict": "1.0.1 <= v < 2.0.0"
     },
     "elm-version": "0.17.1 <= v < 0.18.0"