add edit page

frontend/app/Page/EditValue.hs

@@ -0,0 +1,66 @@
+module Page.EditValue
+  ( Model,
+    initialModel,
+    Action,
+    updateModel,
+    viewModel,
+  )
+where
+
+import Api
+import Data.Aeson qualified as A
+import Data.Aeson.KeyMap qualified as AM
+import Data.Maybe
+import Form qualified as F
+import Miso
+import Miso.String (toMisoString)
+import Schema
+
+data Model = Model
+  { collection :: String,
+    fileName :: String,
+    input :: Maybe A.Value,
+    schema :: Schema
+  }
+  deriving (Show, Eq)
+
+initialModel :: String -> String -> JSM (Either String Model)
+initialModel collection fileName = do
+  schema' <- fetchSchema
+  input' <- fetchPost fileName
+  pure do
+    schema <- schema'
+    input <- input'
+    pure $ Model {..}
+
+data Action
+  = NoOp
+  | FormChanged A.Value
+  | FormSubmitted A.Value
+  | EntityWritten (Either String ())
+  deriving (Eq, Show)
+
+updateModel :: Action -> Model -> Effect Action Model
+updateModel NoOp m = noEff m
+updateModel (FormChanged (Just -> input)) m = noEff m {input}
+updateModel (FormSubmitted output) m =
+  m <# do EntityWritten <$> updatePost m.fileName output
+updateModel (EntityWritten _) m = noEff m
+
+viewModel :: Model -> View Action
+viewModel m = do
+  let input = (fromMaybe (A.Object AM.empty) m.input)
+  div_ [] $
+    [ viewForm input m.schema,
+      viewInput input
+    ]
+
+viewForm :: A.Value -> Schema -> View Action
+viewForm input =
+  fmap (either FormChanged FormSubmitted)
+    . flip F.runForm input
+    . schemaForm
+
+viewInput :: A.Value -> View Action
+viewInput input =
+  pre_ [] [text (toMisoString (A.encode input))]