{-# LANGUAGE DeriveAnyClass     #-}
{-# LANGUAGE DerivingStrategies #-}
{-# LANGUAGE DerivingVia        #-}
{-# LANGUAGE RecordWildCards    #-}


module OwnTracks.Status
-- | https://owntracks.org/booklet/tech/json/
  (Status(..)) where

import           Data.Aeson
import           Data.Aeson.Types       (Parser)
import           Data.ByteString        (ByteString)
import           Data.ByteString.Base64
import           Data.Data              (Proxy (..))
import           Data.Functor           ((<&>))
import           Data.Text              (Text)
import qualified Data.Text              as T
import           Data.Text.Encoding     (encodeUtf8)
import           Data.Time              (UTCTime, defaultTimeLocale, parseTimeM)
import           GHC.Generics           (Generic)


-- | An owntracks message with _type=status.
--
-- Currently only implements android-specific fields.
data Status = Status
  { statusId                   :: Maybe Text
  -- ^ random identifier to be used by consumers to correlate & distinguish send/return messages (Android/string)
  , statusCanHibernate         :: Maybe Int
  -- ^ app can hibernate if not used (Android/integer)
  , statusBatteryOptimizations :: Maybe Int
  -- ^ app is configured with battery optimizations (Android/integer)
  , statusLocationPermission   :: Maybe Int
  -- ^ app location permissions (Android/integer)
  , statusPhonePowerSaveMode   :: Maybe Int
  -- ^ phone power save mode (Android/integer)
  , statusWifiOnOff            :: Maybe Int
  -- ^ wifi is on/off (Android/integer)
  } deriving (Generic, Eq, Show)

instance FromJSON Status where
  parseJSON (Object v) = do
    a <- v .:? "android"
    Status
      <$> v .:? "_id"
      <*> a .:?? "hib"
      <*> a .:?? "bo"
      <*> a .:?? "loc"
      <*> a .:?? "ps"
      <*> a .:?? "wifi"
      where
        (.:??) :: FromJSON a => Maybe Object -> Data.Aeson.Key -> Parser (Maybe a)
        (.:??) Nothing  = const $ pure Nothing
        (.:??) (Just a) = (.:?) a

instance ToJSON Status where
  toJSON Status{..} = object
     [ "_id" .= statusId
     , "hib" .= statusCanHibernate
     , "bo" .= statusBatteryOptimizations
     , "loc" .= statusLocationPermission
     , "ps" .= statusPhonePowerSaveMode
     , "wifi" .= statusWifiOnOff
     ]

  toEncoding Status{..} =
    pairs ("_id" .= statusId
           <> "hib" .= statusCanHibernate
           <> "bo" .= statusBatteryOptimizations
           <> "loc" .= statusLocationPermission
           <> "ps" .= statusPhonePowerSaveMode
           <> "wifi" .= statusWifiOnOff
          )