{-# LANGUAGE DeriveAnyClass #-}

module Gargantext.API.GraphQL.User where

import Data.Maybe (listToMaybe)
import Data.Morpheus.Types
  ( GQLType
  , Resolver, QUERY
  , lift
  )
import Data.Text (Text)
import Gargantext.API.Prelude (GargM, GargError)
import Gargantext.Core.Mail.Types (HasMail)
import Gargantext.Database.Admin.Types.Hyperdata (HyperdataUser(..))
import Gargantext.Database.Prelude (HasConnectionPool, HasConfig)
import Gargantext.Database.Query.Table.User (getUsersWithId, getUserHyperdata)
import Gargantext.Database.Schema.User (UserLight(..))
import Gargantext.Prelude
import GHC.Generics (Generic)

data User m = User
  { u_email     :: Text
  , u_hyperdata :: m (Maybe HyperdataUser)
  , u_id        :: Int
  , u_username  :: Text }
  deriving (Generic, GQLType)

-- | Arguments to the "user" query.
data UserArgs
  = UserArgs
    { user_id :: Int
    } deriving (Generic, GQLType)

type GqlM e env = Resolver QUERY e (GargM env GargError)

-- | Function to resolve user from a query.
resolveUsers
  :: (HasConnectionPool env, HasConfig env, HasMail env)
  => UserArgs -> GqlM e env [User (GqlM e env)]
resolveUsers UserArgs { user_id } = dbUsers user_id

-- | Inner function to fetch the user from DB.
dbUsers
  :: (HasConnectionPool env, HasConfig env, HasMail env)
  => Int -> GqlM e env ([User (GqlM e env)])
dbUsers user_id = lift (map toUser <$> getUsersWithId user_id)

toUser
  :: (HasConnectionPool env, HasConfig env, HasMail env)
  => UserLight -> User (GqlM e env)
toUser (UserLight { .. }) = User { u_email = userLight_email
                                 , u_hyperdata = resolveHyperdata userLight_id
                                 , u_id = userLight_id
                                 , u_username = userLight_username }

resolveHyperdata
  :: (HasConnectionPool env, HasConfig env, HasMail env)
  => Int -> GqlM e env (Maybe HyperdataUser)
resolveHyperdata userid = lift (listToMaybe <$> getUserHyperdata userid)