{-|
Module      : Gargantext.API.Prelude
Description : Server API main Types
Copyright   : (c) CNRS, 2017-Present
License     : AGPL + CECILL v3
Maintainer  : team@gargantext.org
Stability   : experimental
Portability : POSIX

-}

{-# LANGUAGE ConstraintKinds #-}
{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE MonoLocalBinds  #-}

module Gargantext.API.Prelude
  ( module Gargantext.API.Prelude
  , HasServerError(..)
  , serverError
  )
  where

import Control.Concurrent (threadDelay)
import Control.Exception (Exception)
import Control.Lens (Prism', (#))
import Control.Lens.TH (makePrisms)
import Control.Monad.Except (ExceptT)
import Control.Monad.Reader (ReaderT)
import Control.Monad.Error.Class (MonadError(..))
import Crypto.JOSE.Error as Jose
import Data.Aeson.Types
import qualified Data.Text as Text
import Data.Typeable
import Data.Validity
import Gargantext.API.Admin.Orchestrator.Types
import Gargantext.API.Admin.Types
import Gargantext.Core.NodeStory
import Gargantext.Core.Mail.Types (HasMail)
import Gargantext.Core.Types
import Gargantext.Database.Prelude
import Gargantext.Database.Query.Table.Node.Error (NodeError(..), HasNodeError(..))
import Gargantext.Database.Query.Tree
import Gargantext.Prelude
import qualified Gargantext.Utils.Jobs.Monad as Jobs
import Servant
import Servant.Job.Async
import Servant.Job.Core (HasServerError(..), serverError)

class HasJoseError e where
  _JoseError :: Prism' e Jose.Error

joseError :: (MonadError e m, HasJoseError e) => Jose.Error -> m a
joseError = throwError . (_JoseError #)

type HasJobEnv' env = HasJobEnv env JobLog JobLog

type EnvC env =
  ( HasConnectionPool env
  , HasSettings       env  -- TODO rename HasDbSettings
  , HasJobEnv         env JobLog JobLog
  , HasConfig         env
  , HasNodeStoryEnv   env
  , HasMail           env
  )

type ErrC err =
  ( HasNodeError     err
  , HasInvalidError  err
  , HasTreeError     err
  , HasServerError   err
  , HasJoseError     err
--  , ToJSON           err -- TODO this is arguable
  , Exception        err
  )

type GargServerC env err m =
  ( CmdRandom    env err m
  , HasNodeStory env err m
  , EnvC         env
  , ErrC             err
  , ToJSON           err
  )

type GargServerT env err m api = GargServerC env err m => ServerT api m

type GargServer api = forall env err m. GargServerT env err m api

-- This is the concrete monad. It needs to be used as little as possible.
type GargM env err = ReaderT env (ExceptT err IO)
-- This is the server type using GargM. It needs to be used as little as possible.
-- Instead, prefer GargServer, GargServerT.
type GargServerM env err api = (EnvC env, ErrC err) => ServerT api (GargM env err)

-------------------------------------------------------------------
-- | This Type is needed to prepare the function before the GargServer
type GargNoServer t =
  forall env err m. GargNoServer' env err m => m t

type GargNoServer' env err m =
  ( CmdM           env err m
  , HasNodeStory   env err m
  , HasSettings    env
  , HasNodeError       err
  )

-------------------------------------------------------------------
data GargError
  = GargNodeError    NodeError
  | GargTreeError    TreeError
  | GargInvalidError Validation
  | GargJoseError    Jose.Error
  | GargServerError  ServerError
  | GargJobError     Jobs.JobError
  deriving (Show, Typeable)

makePrisms ''GargError

instance ToJSON GargError where
  toJSON err = object [("error", String $ Text.pack $ show err)]

instance Exception GargError

instance HasNodeError GargError where
  _NodeError = _GargNodeError

instance HasInvalidError GargError where
  _InvalidError = _GargInvalidError

instance HasTreeError GargError where
  _TreeError = _GargTreeError

instance HasServerError GargError where
  _ServerError = _GargServerError

instance HasJoseError GargError where
  _JoseError = _GargJoseError

------------------------------------------------------------------------
-- | Utils
-- | Simulate logs
simuLogs  :: MonadBase IO m
         => (JobLog -> m ())
         -> Int
         -> m JobLog
simuLogs logStatus t = do
  _ <- mapM (\n -> simuTask logStatus n t) $ take t [0,1..]
  pure $ JobLog { _scst_succeeded = Just t
                , _scst_failed    = Just 0
                , _scst_remaining = Just 0
                , _scst_events    = Just []
                }

simuTask :: MonadBase IO m
          => (JobLog -> m ())
          -> Int
          -> Int
          -> m ()
simuTask logStatus cur total = do
  let m = (10 :: Int) ^ (6 :: Int)
  liftBase $ threadDelay (m*5)

  let status =  JobLog { _scst_succeeded = Just cur
                       , _scst_failed    = Just 0
                       , _scst_remaining = (-) <$> Just total <*> Just cur
                       , _scst_events    = Just []
                       }
  -- printDebug "status" status
  logStatus status