{-# LANGUAGE DeriveGeneric #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE NoImplicitPrelude #-}

-- | General utils for apps
module Biz.App
  ( Area (..),
    CSS (..),
    HasCss (..),
    Manifest (..),
    Html (..),
  )
where

import Alpha
import qualified Clay
import Data.Aeson (ToJSON)
import qualified Data.Text.Lazy as Lazy
import qualified Data.Text.Lazy.Encoding as Lazy
import Network.HTTP.Media
  ( (//),
    (/:),
  )
import Servant.API (Accept (..), MimeRender (..))
import qualified System.Envy as Envy

data Area = Test | Live
  deriving (Generic, Show)

instance Envy.Var Area where
  toVar = show
  fromVar "Test" = Just Test
  fromVar "Live" = Just Live
  fromVar _ = Just Test

newtype CSS = CSS
  { unCSS :: Text
  }

instance Accept CSS where
  contentType _ = "text" // "css" /: ("charset", "utf-8")

instance MimeRender CSS Text where
  mimeRender _ = Lazy.encodeUtf8 <. Lazy.fromStrict

-- | The manifest describes your app for web app thumbnails, iPhone tiles, etc.
data Manifest = Manifest
  { name :: Text,
    short_name :: Text,
    start_url :: Text,
    display :: Text,
    theme_color :: Text,
    description :: Text
  }
  deriving (Show, Eq, Generic)

instance ToJSON Manifest

-- | A wrapper for an HTML page. You need to provide an orphan
-- 'Lucid.Base.ToHtml' instance in the web module of your app.
--
-- Ideally this would be captured in a Biz.App type, with overrides for head
-- elements, and we would wouldn't have to make the same basic orphan instance
-- for each app.
newtype Html a = Html a
  deriving (Show, Eq)

-- | Class for attaching some CSS to a page specifically.
class HasCss a where
  cssFor :: a -> Clay.Css