[actual working timer
Ganesh Sittampalam <ganesh@earth.li>**20200713065909
 Ignore-this: a0d8f1abef9aa3da81687d7c48d88f28845c05fd4694bbe55c33352c9cce904af06b58f691a56b8a
] hunk ./household.cabal 25
+                      ,servant-js
hunk ./household.cabal 29
-                      ,wai-cors
hunk ./household.cabal 31
+                      ,text
hunk ./src/Core.hs 4
+import Control.Concurrent.MVar
hunk ./src/Core.hs 9
+import Data.Text
hunk ./src/Core.hs 16
+import Servant.JS
hunk ./src/Core.hs 19
-import Network.Wai.Middleware.Cors
hunk ./src/Core.hs 20
-data TimerState =
-  TimerState
+data TimeLeft =
+  TimeLeft
hunk ./src/Core.hs 25
-  deriving (Generic, ToJSON, FromJSON)
-
-type Api =
-  "timer" :> Get '[JSON] TimerState
-
-theServer :: Server Api
-theServer = do
-  theTime <- liftIO getCurrentTime
-  return (TimerState 1 (fromIntegral (diffTimeToPicoseconds (utctDayTime theTime) `div` 1000000000000 `mod` 60)))
-
-application :: Application
-application = simpleCors $ serve (Proxy @Api) theServer
+  deriving (Generic, ToJSON, FromJSON, Show)
+
+data TimerState = Stopped NominalDiffTime | RunningTill UTCTime
+
+type Api = TimerApi :<|> JSApi :<|> Raw
+
+type TimerApi =
+  "timer" :>
+  (
+       "current" :> (Get '[JSON] TimeLeft :<|> ReqBody '[JSON] TimeLeft :> PutNoContent)
+  :<|> "stop" :> PostNoContent
+  :<|> "start" :> PostNoContent
+  )
+
+type JSApi = "js" :> ("api" :> ("vanilla" :> Get '[PlainText] Text :<|> "jquery" :> Get '[PlainText] Text))
+
+getCurrent :: MVar TimerState -> Handler TimeLeft
+getCurrent state = do
+  timerState <- liftIO $ readMVar state
+  timeLeft <-
+    case timerState of
+      Stopped timeLeft -> return timeLeft
+      RunningTill endTime -> do
+        theTime <- liftIO getCurrentTime
+        return $ max 0 (endTime `diffUTCTime` theTime)
+  return $ uncurry TimeLeft $ floor timeLeft `divMod` 60
+
+setCurrent :: MVar TimerState -> TimeLeft -> Handler NoContent
+setCurrent state newTime = do
+  liftIO $ do
+    putStrLn $ "setCurrent: " ++ show newTime
+    modifyMVar_ state $ \_ ->
+      return $ Stopped $ fromIntegral (60 * timeLeftMins newTime + timeLeftSecs newTime)
+  return NoContent
+
+startTimer :: MVar TimerState -> Handler NoContent
+startTimer state = do
+  liftIO $ do
+    putStrLn $ "startTimer"
+    modifyMVar_ state $ \timerState ->
+      case timerState of
+        RunningTill {} -> return timerState
+        Stopped timeLeft -> do
+          theTime <- liftIO getCurrentTime
+          return $ RunningTill $ timeLeft `addUTCTime` theTime
+  return NoContent
+
+stopTimer :: MVar TimerState -> Handler NoContent
+stopTimer state = do
+  liftIO $ do
+    putStrLn $ "stopTimer"
+    modifyMVar_ state $ \timerState ->
+      case timerState of
+        Stopped {} -> return timerState
+        RunningTill endTime -> do
+          theTime <- liftIO getCurrentTime
+          return $ Stopped $ max 0 $ endTime `diffUTCTime` theTime
+    return NoContent
+
+jsCode :: JavaScriptGenerator -> Handler Text
+jsCode thing = Prelude.return (jsForAPI (Proxy @TimerApi) thing)
+
+js :: Server JSApi
+js = jsCode vanillaJS :<|> jsCode jquery
+
+theServer :: MVar TimerState -> Server Api
+theServer state =
+       ((getCurrent state :<|> setCurrent state) :<|> stopTimer state :<|> startTimer state)
+  :<|> js
+  :<|> serveDirectoryFileServer "static/"
+
+application :: MVar TimerState -> Application
+application state = serve (Proxy @Api) (theServer state)
hunk ./src/Core.hs 102
-  race_ (run port application) $ do
+  state <- newMVar (Stopped 0)
+  race_ (run port (application state)) $ do
hunk ./src/Core.hs 108
-
hunk ./static/timer.html 12
-
+        <script src="/js/api/vanilla"></script>
hunk ./static/timer.html 17
+        <button onclick="set(10,0)" id="set10">10 minutes</button>
+        <button onclick="start()" id="start">Start</button>
+        <button onclick="stop()" id="stop">Stop</button>
hunk ./static/timer.html 21
+            function set(mins, secs) {
+                putTimerCurrent({timeLeftMins : mins, timeLeftSecs : secs}, () => {}, () => {});
+            }
+            function start() {
+                postTimerStart(() => {}, () => {});
+            }
+            function stop() {
+                postTimerStop(() => {}, () => {});
+            }
hunk ./static/timer.html 48
-                    fetch("http://localhost:8001/timer")
+                    fetch("/timer/current")
hunk ./static/timer.html 66
-                        return <div>{payload.timeLeftMins}:{payload.timeLeftSecs}</div>;
+                        var formattedSeconds = ("0" + payload.timeLeftSecs).slice(-2);
+                        return <div>{payload.timeLeftMins}:{formattedSeconds}</div>;