starts with a dedicated Api module, wip...

src/Api.elm

@@ -0,0 +1,173 @@
+module Api exposing (..)
+
+import Http
+import Json.Decode as D
+import Json.Decode exposing (Decoder, int, string)
+import Json.Encode as E
+
+type alias HttpResult a = (Result Http.Error a)
+
+type alias Response =
+    { value: Maybe String
+    , notification: Maybe String
+    , updates : Maybe (List Update)
+    , errors : Maybe String
+    }
+
+
+type Update
+    = ItemRemoved Item
+    | ItemAdded Item
+    | WealthUpdated Wealth
+    | ClaimAdded ()
+    | ClaimRemoved ()
+
+type Msg
+    = GotPlayer (HttpResult Player)
+    | GotClaims Int (HttpResult Claims)
+    | GotLoot ToChest (HttpResult Loot)
+    | GotActionResult (HttpResult Response)
+
+-- PLAYERS
+--
+
+fetchPlayer : Int -> Cmd Msg
+fetchPlayer id =
+    Http.get
+        { url = "http://localhost:8088/api/players/" ++ (String.fromInt id) ++ "/"
+        , expect = Http.expectJson Main.GotPlayer (valueDecoder playerDecoder )
+        }
+
+playerDecoder : Decoder Player
+playerDecoder =
+    D.map4 Player
+    (D.field "id" int)
+    (D.field "name" string)
+    (D.field "debt" int)
+    wealthDecoder
+
+wealthDecoder : Decoder Wealth
+wealthDecoder =
+    D.map4 Wealth
+        (D.field "cp" int)
+        (D.field "sp" int)
+        (D.field "gp" int)
+        (D.field "pp" int)
+
+-- LOOT
+
+-- Location of a loot
+type ToChest
+    = OfPlayer Int
+    | OfGroup
+    | OfShop
+
+itemDecoder =
+    D.map3 Item
+        (D.field "id" int)
+        (D.field "name" string)
+        (D.field "base_price" int)
+
+lootDecoder : Decoder Loot
+lootDecoder =
+    Json.Decode.list itemDecoder
+
+fetchLoot : Main.ToChest -> Cmd Msg
+fetchLoot dest =
+    let
+        url = case dest of
+            Main.OfPlayer id -> "http://localhost:8088/api/players/" ++ (String.fromInt id) ++ "/loot"
+            Main.OfShop -> "http://localhost:8088/api/items"
+            Main.OfGroup -> "http://localhost:8088/api/players/0/loot"
+    in
+    Http.get
+        { url = url
+        , expect = Http.expectJson (GotLoot dest) (valueDecoder lootDecoder)}
+
+-- CLAIMS
+
+claimDecoder =
+    D.map3 Claim
+        (D.field "id" int)
+        (D.field "player_id" int)
+        (D.field "loot_id" int)
+
+fetchClaims : Int -> Cmd Msg
+fetchClaims playerId =
+    Http.get
+        { url = "http://localhost:8088/api/claims"
+        , expect = valueDecoder (D.list claimDecoder)
+          |> Http.expectJson (GotClaims playerId)
+        }
+
+-- API Response
+--
+valueDecoder : Decoder a -> Decoder a
+valueDecoder thenDecoder =
+    D.field "value" thenDecoder
+
+-- TODO: update server to produce better json
+--       like an object with list of updates of the same type
+--       { ItemRemoved : [..], Wealth : [ .. ], .. }
+updatesDecoder : Decoder DbUpdate
+updatesDecoder =
+    -- We expect one update but do not know it's kind
+            Json.Decode.oneOf
+                [ (field "ItemRemoved" (itemDecoder |> Json.Decode.andThen (\i -> succeed <| ItemRemoved i)))
+                , (field "ItemAdded" (itemDecoder |> Json.Decode.andThen (\i -> succeed <| ItemAdded i)))
+                , (field "Wealth" (wealthDecoder |> Json.Decode.andThen (\i -> succeed <| WealthUpdated i)))
+                , (field "ClaimRemoved" (succeed () |> Json.Decode.andThen (\i -> succeed <| ClaimRemoved i)))
+                , (field "ClaimAdded" (succeed () |> Json.Decode.andThen (\i -> succeed <| ClaimAdded i)))
+                ]
+
+
+apiResponseDecoder : Decoder ApiResponse
+apiResponseDecoder =
+    Json.Decode.map4 ApiResponse
+        (D.maybe (field "value" string))
+        (Json.Decode.maybe (field "notification" string))
+        (Json.Decode.maybe (field "updates" (Json.Decode.list updatesDecoder)))
+        (Json.Decode.maybe (field "errors" string))
+
+undoLastAction id = Http.request
+            { url = "http://localhost:8088/api/players/" ++ String.fromInt id ++"/events/last"
+            , method = "DELETE"
+            , headers = []
+            , body = Http.emptyBody
+            , expect = Http.expectJson GotActionResult apiResponseDecoder
+            , timeout = Nothing
+            , tracker = Nothing
+            }
+
+sendRequest : Maybe ViewMode -> Model -> Cmd Msg
+sendRequest activeMode model =
+    case activeMode of
+        Nothing -> Cmd.none
+        Just mode ->
+            let
+                (endpoint, method) = case mode of
+                    Add ->
+                        ( "http://localhost:8088/api/players/" ++ (String.fromInt model.player.id) ++ "/loot"
+                        , "POST"
+                        )
+                    Buy ->
+                        ( "http://localhost:8088/api/players/" ++ (String.fromInt model.player.id) ++ "/loot"
+                        , "PUT"
+                        )
+                    Sell ->
+                        ( "http://localhost:8088/api/players/" ++ (String.fromInt model.player.id) ++ "/loot"
+                        , "DELETE"
+                        )
+                    Grab ->
+                        ( "http://localhost:8088/api/players/" ++ (String.fromInt model.player.id) ++ "/claims"
+                        , "POST")
+            in
+            Http.request
+                { method = method
+                , headers = []
+                , url = endpoint
+                , body = Http.jsonBody <| buildPayload mode model
+                , expect = Http.expectJson GotActionResult apiResponseDecoder
+                , timeout = Nothing
+                , tracker = Nothing
+                }