module View.Income.Form
  ( view
  , FormIn(..)
  , HttpMethod(..)
  , FormOut(..)
  ) where

import           Data.Aeson               (ToJSON)
import           Data.Text                (Text)
import qualified Data.Text                as T
import           Data.Time.Calendar       (Day)
import qualified Data.Time.Calendar       as Calendar
import qualified Data.Validation          as V
import           Reflex.Dom               (Event, MonadWidget)
import qualified Reflex.Dom               as R

import           Common.Model             (Income)
import qualified Common.Msg               as Msg
import qualified Common.Validation.Income as IncomeValidation
import           Component                (ButtonIn (..), InputIn (..),
                                           InputOut (..))
import qualified Component                as Component
import qualified Util.Ajax                as Ajax
import qualified Util.Either              as EitherUtil
import qualified Util.Validation          as ValidationUtil
import qualified Util.WaitFor             as WaitFor

data FormIn t i = FormIn
  { _formIn_cancel      :: Event t ()
  , _formIn_headerLabel :: Text
  , _formIn_amount      :: Text
  , _formIn_date        :: Day
  , _formIn_mkPayload   :: Text -> Text -> i
  , _formIn_httpMethod  :: HttpMethod
  }

data HttpMethod = Put | Post

data FormOut t = FormOut
  { _formOut_hide      :: Event t ()
  , _formOut_addIncome :: Event t Income
  }

view :: forall t m i. (MonadWidget t m, ToJSON i) => FormIn t i -> m (FormOut t)
view formIn = do
  R.divClass "form" $ do
    R.divClass "formHeader" $
      R.text (_formIn_headerLabel formIn)

    R.divClass "formContent" $ do
      rec
        let reset = R.leftmost
              [ "" <$ cancel
              , "" <$ addIncome
              , "" <$ _formIn_cancel formIn
              ]

        amount <- _inputOut_raw <$> (Component.input
          (Component.defaultInputIn
            { _inputIn_label = Msg.get Msg.Income_Amount
            , _inputIn_initialValue = _formIn_amount formIn
            , _inputIn_validation = IncomeValidation.amount
            })
          (_formIn_amount formIn <$ reset)
          confirm)

        let initialDate = T.pack . Calendar.showGregorian . _formIn_date $ formIn

        date <- _inputOut_raw <$> (Component.input
          (Component.defaultInputIn
            { _inputIn_label = Msg.get Msg.Income_Date
            , _inputIn_initialValue = initialDate
            , _inputIn_inputType = "date"
            , _inputIn_hasResetButton = False
            , _inputIn_validation = IncomeValidation.date
            })
          (initialDate <$ reset)
          confirm)

        let income = do
              a <- amount
              d <- date
              return . V.Success $ (_formIn_mkPayload formIn) a d

        (addIncome, cancel, confirm) <- R.divClass "buttons" $ do
          rec
            cancel <- Component._buttonOut_clic <$> (Component.button $
              (Component.defaultButtonIn (R.text $ Msg.get Msg.Dialog_Undo))
                { _buttonIn_class = R.constDyn "undo" })

            confirm <- Component._buttonOut_clic <$> (Component.button $
              (Component.defaultButtonIn (R.text $ Msg.get Msg.Dialog_Confirm))
                { _buttonIn_class = R.constDyn "confirm"
                , _buttonIn_waiting = waiting
                , _buttonIn_submit = True
                })

            (addIncome, waiting) <- WaitFor.waitFor
              (ajax "/api/income")
              (ValidationUtil.fireValidation income confirm)

          return (R.fmapMaybe EitherUtil.eitherToMaybe addIncome, cancel, confirm)

      return FormOut
        { _formOut_hide = R.leftmost [ cancel, () <$ addIncome ]
        , _formOut_addIncome = addIncome
        }

  where
    ajax =
      case _formIn_httpMethod formIn of
        Post -> Ajax.postJson
        Put  -> Ajax.putJson