{-# LANGUAGE OverloadedStrings #-}

module Backend.Http
  ( HttpConfiguration (..),
    httpDefaultSettings,
  )
where

import Data.String
import qualified Data.Text as T
import Network.Wai.Handler.Warp as HTTP
import Toml (TomlCodec, (.=))
import Control.Concurrent
import Control.Concurrent.MVar
import qualified Toml
import Validation

-- We leave it as a Text here and defer the conversion to the warp type to the last possible moment.
-- At least we can touch and print a String. Excepet that we don't use it so we don't need it in another
-- form

-- even though this is just a String alias, we leave the infrastructure in place. Maybe we want to change that
-- type at some point. Then we can redifne the stuff to work with our new type.
-- One can think about this as being accidantally a String, and not by design.
type BindPreference = String

_BindPreference :: Toml.TomlBiMap BindPreference Toml.AnyValue
_BindPreference = Toml._String

bindPreference :: Toml.Key -> TomlCodec BindPreference
bindPreference = Toml.match _BindPreference

data HttpConfiguration = HttpConfiguration
  { port :: Int,
    bindPref :: BindPreference
  }

httpDefaultSettings :: HttpConfiguration
httpDefaultSettings = HttpConfiguration 80 "*"

-- why a String? Why is the only way to generate a HostPreference by its IsString instance?
-- why does warp not expose its constructors??
httpConfigConstructor :: Int -> String -> HTTP.Settings
httpConfigConstructor port bind = HTTP.setPort port $ HTTP.setHost (fromString bind) HTTP.defaultSettings

httpConfigCodec :: TomlCodec HttpConfiguration
httpConfigCodec =
  HttpConfiguration
    <$> Toml.int "Port" .= port
    <*> bindPreference "Bind" .= bindPref

forkHttpBackend :: Toml.TOML -> IO [MVar ()]
forkHttpBackend ast = undefined