import Data.Functor ((<&>))
import Data.Text (Text)
import Text.Parsec (char, digit, many1)
import Text.Regex.TDFA ((=~))
import System.Console.Ask (Ask, ask, askOptional, askOrElse, runAsk, defaultBehaviour)
import System.Console.Ask.Askable (Askable (fromText), fromParsec)
data UserInformation = UserInformation
    { name                   :: Text
    , age                    :: Maybe Int
    , birthday               :: Date
    , notificationPreference :: NotificationPreference
    } deriving Show
data NotificationPreference = NotificationPreference
    { needNotifications :: Bool
    , emailAddress      :: Maybe EmailAddress
    } deriving Show
askUserInformation :: Ask UserInformation
askUserInformation =
    UserInformation
        <$> ask         "What is your name?"
        <*> askOptional "How old are you?"
        <*> ask         "When is your birthday?"
        <*> askNotificationPreference
askNotificationPreference :: Ask NotificationPreference
askNotificationPreference = do
    needNotifications' <- askOrElse "Do you need our update notifications?" False
    emailAddress' <-
        if needNotifications'
            then Just <$> ask "What is your email address?"
            else pure Nothing
    pure NotificationPreference
        { needNotifications = needNotifications'
        , emailAddress      = emailAddress'
        }
newtype EmailAddress = EmailAddress Text deriving Show
instance Askable EmailAddress where
    fromText text =
        if text =~ ("[a-zA-Z0-9+._-]+@[a-zA-Z-]+\\.[a-z]+" :: Text)
            then Just (EmailAddress text)
            else Nothing
data Date = Date Int Int deriving Show
instance Askable Date where
    fromText = fromParsec $ do
        day   <- many1 digit <&> read
        _     <- char '/'
        month <- many1 digit <&> read
        pure (Date day month)
main :: IO ()
main = do
    userInfo <- runAsk defaultBehaviour askUserInformation
    print userInfo

What is your name?
> Toma Sasaki
How old are you?
>
When is your birthday?
> 15/9
Do you need our update notifications? (Default: False)
> aye
What is your email address?
> me@t-sasaki.net
UserInformation
    { name = "Toma Sasaki"
    , age = Nothing
    , birthday = Date 15 9
    , notificationPreference =
        NotificationPreference
            { needNotifications = True
            , emailAddress = Just (EmailAddress "me@t-sasaki.net")
            }
    }

import Control.Monad.IO.Class (liftIO)
import Data.Text (Text)
import qualified Data.Text as Text
import qualified Data.Text.IO as TextIO
import System.Console.Ask (Ask, ask, askOptional, askOrElse, defaultBehaviour, runAsk)
main :: IO ()
main = runAsk defaultBehaviour $ do
    name              <- ask         "What is your name?"               :: Ask Text
    age               <- askOptional "How old are you?"                 :: Ask (Maybe Int)
    needNotifications <- askOrElse   "Do you need notifications?" False :: Ask Bool
    liftIO $ do
        TextIO.putStrLn ("Name: " <> name)
        TextIO.putStrLn ("Age: " <> Text.show age)
        TextIO.putStrLn ("Need notifications: " <> Text.show needNotifications)

What is your name?
> Toma Sasaki
How old are you?
> a
Invalid input.
How old are you?
> 18
Do you need notifications? (Default: False)
> no
Name: Toma Sasaki
Age: 18
Need notifications: False

import Data.Functor ((<&>))
import Data.Text (Text)
import Text.Parsec (char, digit, many1)
import Text.Regex.TDFA ((=~))
import System.Console.Ask.Askable (Askable (fromText), fromParsec)
newtype EmailAddress = EmailAddress Text deriving Show
instance Askable EmailAddress where
    fromText text =
        if text =~ ("[a-zA-Z0-9+._-]+@[a-zA-Z-]+\\.[a-z]+" :: Text)
            then Just (EmailAddress text)
            else Nothing
data Date = Date Int Int deriving Show
instance Askable Date where
    fromText = fromParsec $ do
        day   <- many1 digit <&> read
        _     <- char '/'
        month <- many1 digit <&> read
        pure (Date day month)

import Control.Monad.IO.Class (liftIO)
import Data.Text (Text)
import qualified Data.Text as Text
import qualified Data.Text.IO as TextIO
import System.Console.Ask (Ask, ask', askOptional', askOrElse', defaultBehaviour, runAsk)
main :: IO ()
main = runAsk defaultBehaviour $ do
    name              <- ask'         "What is your name?"               "Text> " :: Ask Text
    age               <- askOptional' "How old are you?"                 "Int > " :: Ask (Maybe Int)
    needNotifications <- askOrElse'   "Do you need notifications?" False "Y/N > " :: Ask Bool
    liftIO $ do
        TextIO.putStrLn ("Name: " <> name)
        TextIO.putStrLn ("Age: " <> Text.show age)
        TextIO.putStrLn ("Need notifications: " <> Text.show needNotifications)

What is your name?
Text> Toma Sasaki
How old are you?
Int > 18
Do you need notifications? (Default: False)
Y/N > True
Name: Toma Sasaki
Age: 18
Need notifications: True

import Control.Monad.IO.Class (liftIO)
import Data.Text (Text)
import qualified Data.Text as Text
import qualified Data.Text.IO as TextIO
import System.Console.Ask (Ask, ask, askOptional, askOrElse, defaultBehaviour, runAsk, withBehaviour)
import System.Console.Ask.Behaviour (DefaultValueStyle (..), defaultValueStyle, invalidInputErrorMsg, set)
main :: IO ()
main = runAsk defaultBehaviour $ do
    let customBehaviour1 = set invalidInputErrorMsg (Just "??????") defaultBehaviour
        customBehaviour2 = set defaultValueStyle OnNewline defaultBehaviour
    name              <- ask "What is your name?" :: Ask Text
    age               <- withBehaviour customBehaviour1 (askOptional "How old are you?")                 :: Ask (Maybe Int)
    needNotifications <- withBehaviour customBehaviour2 (askOrElse   "Do you need notifications?" False) :: Ask Bool
    liftIO $ do
        TextIO.putStrLn ("Name: " <> name)
        TextIO.putStrLn ("Age: " <> Text.show age)
        TextIO.putStrLn ("Need notifications: " <> Text.show needNotifications)

What is your name?
> Toma Sasaki
How old are you?
> a
??????
How old are you?
> 18
Do you need notifications?
Default: False
> True
Name: Toma Sasaki
Age: 18
Need notifications: True