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

Main REST API of Gargantext (both Server and Client sides)
Thanks @yannEsposito for our discussions at the beginning of this project :).

-}

{-# OPTIONS_GHC -fno-warn-name-shadowing #-}

{-# LANGUAGE ConstraintKinds      #-}
{-# LANGUAGE NoImplicitPrelude    #-}
{-# LANGUAGE DataKinds            #-}
{-# LANGUAGE DeriveGeneric        #-}
{-# LANGUAGE FlexibleContexts     #-}
{-# LANGUAGE FlexibleInstances    #-}
{-# LANGUAGE OverloadedStrings    #-}
{-# LANGUAGE TemplateHaskell      #-}
{-# LANGUAGE TypeOperators        #-}
{-# LANGUAGE KindSignatures       #-}
{-# LANGUAGE RankNTypes           #-}
{-# LANGUAGE ScopedTypeVariables  #-}
{-# LANGUAGE TypeFamilies         #-}
{-# LANGUAGE UndecidableInstances #-}

---------------------------------------------------------------------
module Gargantext.API
      where
---------------------------------------------------------------------

import           System.IO (FilePath)

import           GHC.Generics (D1, Meta (..), Rep)
import           GHC.TypeLits (AppendSymbol, Symbol)

import           Control.Lens
import           Control.Exception (finally)
import           Control.Monad.Except (withExceptT, ExceptT)
import           Control.Monad.IO.Class (liftIO)
import           Control.Monad.Reader (ReaderT, runReaderT)
import           Data.Aeson.Encode.Pretty (encodePretty)
import qualified Data.ByteString.Lazy.Char8 as BL8
import           Data.Swagger
import           Data.Text (Text)
import qualified Data.Text.IO as T
--import qualified Data.Set as Set
import           Data.Validity

import           Network.Wai
import           Network.Wai.Handler.Warp hiding (defaultSettings)

import           Servant
import           Servant.Auth as SA
import           Servant.Auth.Server (AuthResult(..))
import           Servant.Auth.Swagger ()
import           Servant.HTML.Blaze (HTML)
--import           Servant.Mock (mock)
--import           Servant.Job.Server (WithCallbacks)
import           Servant.Job.Async
import           Servant.Static.TH.Internal.Server (fileTreeToServer)
import           Servant.Static.TH.Internal.FileTree (fileTypeToFileTree, FileType(FileTypeFile))
import           Servant.Swagger
import           Servant.Swagger.UI
-- import Servant.API.Stream
import           Text.Blaze.Html (Html)

--import Gargantext.API.Swagger

import Gargantext.Database.Node.Contact (HyperdataContact)
import Gargantext.API.Auth (AuthRequest, AuthResponse, AuthenticatedUser(..), AuthContext, auth, withAccess, PathId(..))
import Gargantext.API.Count  ( CountAPI, count, Query)
import Gargantext.API.FrontEnd (FrontEndAPI, frontEndServer)
import Gargantext.API.Ngrams (HasRepo(..), HasRepoSaver(..), saveRepo, TableNgramsApi, apiNgramsTableDoc)
import Gargantext.API.Node
import Gargantext.API.Search (SearchPairsAPI, searchPairs)
import Gargantext.API.Types
import qualified Gargantext.API.Corpus.New as New
import Gargantext.Database.Types.Node
import Gargantext.Database.Types.Node (NodeId, CorpusId, AnnuaireId)
import Gargantext.Database.Utils (HasConnection)
import Gargantext.Prelude
import Gargantext.Viz.Graph.API

--import Gargantext.API.Orchestrator
import Gargantext.API.Orchestrator.Types

---------------------------------------------------------------------

import GHC.Base (Applicative)
-- import Control.Lens

import Data.List (lookup)
import Data.Text.Encoding (encodeUtf8)

--import Network.Wai (Request, requestHeaders, responseLBS)
import Network.Wai (Request, requestHeaders)
--import qualified Network.Wai.Handler.Warp as Warp
import Network.Wai.Middleware.Cors

import Network.Wai.Middleware.RequestLogger
-- import qualified Network.Wai.Middleware.RequestLogger as RequestLogger

import Network.HTTP.Types hiding (Query)

import Gargantext.API.Settings

showAsServantErr :: GargError -> ServerError
showAsServantErr (GargServerError err) = err
showAsServantErr a = err500 { errBody = BL8.pack $ show a }

fireWall :: Applicative f => Request -> FireWall -> f Bool
fireWall req fw = do
    let origin = lookup "Origin" (requestHeaders req)
    let host   = lookup "Host"   (requestHeaders req)

    let hostOk   = Just (encodeUtf8 "localhost:3000")
    let originOk = Just (encodeUtf8 "http://localhost:8008")

    if  origin == originOk
       && host == hostOk
       || (not $ unFireWall fw)

       then pure True
       else pure False

{-
-- makeMockApp :: Env -> IO (Warp.Settings, Application)
makeMockApp :: MockEnv -> IO Application
makeMockApp env = do
    let serverApp = appMock

    -- logWare <- mkRequestLogger def { destination = RequestLogger.Logger $ env^.logger }
    --logWare <- mkRequestLogger def { destination = RequestLogger.Logger "/tmp/logs.txt" }
    let checkOriginAndHost app req resp = do
            blocking <- fireWall req (env ^. menv_firewall)
            case blocking  of
                True  -> app req resp
                False -> resp ( responseLBS status401 [] 
                              "Invalid Origin or Host header")
        
    let corsMiddleware = cors $ \_ -> Just CorsResourcePolicy
--          { corsOrigins        = Just ([env^.settings.allowedOrigin], False)
            { corsOrigins        = Nothing --  == /*
            , corsMethods        = [ methodGet   , methodPost   , methodPut
                                   , methodDelete, methodOptions, methodHead]
            , corsRequestHeaders = ["authorization", "content-type"]
            , corsExposedHeaders = Nothing
            , corsMaxAge         = Just ( 60*60*24 ) -- one day
            , corsVaryOrigin     = False
            , corsRequireOrigin  = False
            , corsIgnoreFailures = False
            }

    --let warpS = Warp.setPort (8008 :: Int)   -- (env^.settings.appPort)
    --          $ Warp.defaultSettings
    
    --pure (warpS, logWare $ checkOriginAndHost $ corsMiddleware $ serverApp)
    pure $ logStdoutDev $ checkOriginAndHost $ corsMiddleware $ serverApp
-}


makeDevMiddleware :: IO Middleware
makeDevMiddleware = do

    -- logWare <- mkRequestLogger def { destination = RequestLogger.Logger $ env^.logger }
    --logWare <- mkRequestLogger def { destination = RequestLogger.Logger "/tmp/logs.txt" }
--    let checkOriginAndHost app req resp = do
--            blocking <- fireWall req (env ^. menv_firewall)
--            case blocking  of
--                True  -> app req resp
--                False -> resp ( responseLBS status401 [] 
--                              "Invalid Origin or Host header")
--        
    let corsMiddleware = cors $ \_ -> Just CorsResourcePolicy
--          { corsOrigins        = Just ([env^.settings.allowedOrigin], False)
            { corsOrigins        = Nothing --  == /*
            , corsMethods        = [ methodGet   , methodPost   , methodPut
                                   , methodDelete, methodOptions, methodHead]
            , corsRequestHeaders = ["authorization", "content-type"]
            , corsExposedHeaders = Nothing
            , corsMaxAge         = Just ( 60*60*24 ) -- one day
            , corsVaryOrigin     = False
            , corsRequireOrigin  = False
            , corsIgnoreFailures = False
            }

    --let warpS = Warp.setPort (8008 :: Int)   -- (env^.settings.appPort)
    --          $ Warp.defaultSettings
    
    --pure (warpS, logWare . checkOriginAndHost . corsMiddleware)
    pure $ logStdoutDev . corsMiddleware

---------------------------------------------------------------------
-- | API Global

-- | API for serving @swagger.json@
type SwaggerAPI = SwaggerSchemaUI "swagger-ui" "swagger.json"

-- | API for serving main operational routes of @gargantext.org@


type GargAPI = "api" :> Summary "API " :> GargAPIVersion
-- | TODO          :<|> Summary "Latest API" :> GargAPI'


type GargAPIVersion = "v1.0" :> Summary "v1.0: " :> GargAPI'

type GargAPI' =
           -- Auth endpoint
                "auth"  :> Summary "AUTH API"
                        :> ReqBody '[JSON] AuthRequest
                        :> Post    '[JSON] AuthResponse
           -- TODO-ACCESS here we want to request a particular header for
           -- auth and capabilities.
          :<|> GargPrivateAPI

type GargPrivateAPI = SA.Auth '[SA.JWT] AuthenticatedUser :> GargPrivateAPI'

type GargAdminAPI
              -- Roots endpoint
             =  "user"  :> Summary "First user endpoint"
                        :> Roots
           :<|> "nodes" :> Summary "Nodes endpoint"
                        :> ReqBody '[JSON] [NodeId] :> NodesAPI

type GargPrivateAPI' =
                GargAdminAPI

           -- Node endpoint
           :<|> "node"  :> Summary "Node endpoint"
                        :> Capture "node_id" NodeId
                        :> NodeAPI HyperdataAny

           -- Corpus endpoint
           :<|> "corpus":> Summary "Corpus endpoint"
                        :> Capture "corpus_id" CorpusId
                        :> NodeAPI HyperdataCorpus

           :<|> "corpus":> Summary "Corpus endpoint"
                        :> Capture "node1_id" NodeId
                        :> "document"
                        :> Capture "node2_id" NodeId
                        :> NodeNodeAPI HyperdataAny

           -- Annuaire endpoint
           :<|> "annuaire":> Summary "Annuaire endpoint"
                          :> Capture "annuaire_id" AnnuaireId
                          :> NodeAPI HyperdataAnnuaire

           :<|> "annuaire" :> Summary "Contact endpoint"
                           :> Capture "annuaire_id" NodeId
                           :> "contact" :> Capture "contact_id" NodeId
                           :> NodeNodeAPI HyperdataContact

           -- Document endpoint
           :<|> "document":> Summary "Document endpoint"
                          :> Capture "doc_id" DocId
                          :> "ngrams" :> TableNgramsApi

        -- :<|> "counts" :> Stream GET NewLineFraming '[JSON] Count :> CountAPI
            -- TODO-SECURITY
           :<|> "count" :> Summary "Count endpoint"
                        :> ReqBody '[JSON] Query :> CountAPI

           -- Corpus endpoint --> TODO rename s/search/filter/g
           :<|> "search":> Capture "corpus" NodeId
                        :> SearchPairsAPI

           -- TODO move to NodeAPI?
           :<|> "graph" :> Summary "Graph endpoint"
                        :> Capture "graph_id" NodeId
                        :> GraphAPI

           -- TODO move to NodeAPI?
           -- Tree endpoint
           :<|> "tree" :> Summary "Tree endpoint"
                       :> Capture "tree_id" NodeId
                       :> TreeAPI

           :<|> New.API_v2
       --  :<|> "scraper" :> WithCallbacks ScraperAPI
           :<|> "new"  :> New.Api

-- /mv/<id>/<id>
-- /merge/<id>/<id>
-- /rename/<id>
       -- :<|> "static"
       -- :<|> "list"     :> Capture "node_id" Int  :> NodeAPI
       -- :<|> "ngrams"   :> Capture "node_id" Int  :> NodeAPI
       -- :<|> "auth"     :> Capture "node_id" Int  :> NodeAPI
---------------------------------------------------------------------
type SwaggerFrontAPI = SwaggerAPI :<|> FrontEndAPI

type API = SwaggerFrontAPI :<|> GargAPI :<|> Get '[HTML] Html

-- This is the concrete monad. It needs to be used as little as possible,
-- instead, prefer GargServer, GargServerT, GargServerC.
type GargServerM env err = ReaderT env (ExceptT err IO)

type EnvC env =
  ( HasConnection env
  , HasRepo env
  , HasSettings env
  , HasJobEnv env ScraperStatus ScraperStatus
  )

---------------------------------------------------------------------
-- | Server declarations

server :: forall env. EnvC env => env -> IO (Server API)
server env = do
  -- orchestrator <- scrapyOrchestrator env
  pure $  swaggerFront
     :<|> hoistServerWithContext (Proxy :: Proxy GargAPI) (Proxy :: Proxy AuthContext) transform serverGargAPI
     :<|> serverStatic
  where
    transform :: forall a. GargServerM env GargError a -> Handler a
    transform = Handler . withExceptT showAsServantErr . (`runReaderT` env)

serverGargAPI :: GargServerT env err (GargServerM env err) GargAPI
serverGargAPI -- orchestrator
       =  auth :<|> serverPrivateGargAPI
  --   :<|> orchestrator

serverPrivateGargAPI :: GargServerT env err (GargServerM env err) GargPrivateAPI
serverPrivateGargAPI (Authenticated auser) = serverPrivateGargAPI' auser
serverPrivateGargAPI _                     = throwAll' (_ServerError # err401)
-- Here throwAll' requires a concrete type for the monad.

-- TODO-SECURITY admin only: withAdmin
-- Question: How do we mark admins?
serverGargAdminAPI :: GargServer GargAdminAPI
serverGargAdminAPI
   =  roots
 :<|> nodesAPI

serverPrivateGargAPI' :: AuthenticatedUser -> GargServer GargPrivateAPI'
serverPrivateGargAPI' (AuthenticatedUser (NodeId uid))
       =  serverGargAdminAPI
     :<|> nodeAPI     (Proxy :: Proxy HyperdataAny)      uid
     :<|> nodeAPI     (Proxy :: Proxy HyperdataCorpus)   uid
     :<|> nodeNodeAPI (Proxy :: Proxy HyperdataAny)      uid
     :<|> nodeAPI     (Proxy :: Proxy HyperdataAnnuaire) uid
     :<|> nodeNodeAPI (Proxy :: Proxy HyperdataContact)      uid
     :<|> withAccess  (Proxy :: Proxy TableNgramsApi) Proxy uid <$> PathNode <*> apiNgramsTableDoc
     :<|> count -- TODO: undefined
     :<|> withAccess (Proxy :: Proxy SearchPairsAPI) Proxy uid <$> PathNode <*> searchPairs -- TODO: move elsewhere
     :<|> withAccess (Proxy :: Proxy GraphAPI)       Proxy uid <$> PathNode <*> graphAPI uid -- TODO: mock
     :<|> withAccess (Proxy :: Proxy TreeAPI)        Proxy uid <$> PathNode <*> treeAPI
     :<|> addToCorpus
     :<|> New.api -- TODO-SECURITY
     :<|> New.info uid -- TODO-SECURITY

addToCorpus :: GargServer New.API_v2
addToCorpus cid =
  serveJobsAPI $
    JobFunction (\i log -> New.addToCorpusJobFunction cid i (liftIO . log))

serverStatic :: Server (Get '[HTML] Html)
serverStatic = $(do
                let path = "purescript-gargantext/dist/index.html"
                Just s <- liftIO (fileTypeToFileTree (FileTypeFile path))
                fileTreeToServer s
                )

---------------------------------------------------------------------
swaggerFront :: Server SwaggerFrontAPI
swaggerFront = schemaUiServer swaggerDoc
           :<|> frontEndServer

--gargMock :: Server GargAPI
--gargMock = mock apiGarg Proxy

---------------------------------------------------------------------
makeApp :: EnvC env => env -> IO Application
makeApp env = serveWithContext api cfg <$> server env
  where
    cfg :: Servant.Context AuthContext
    cfg = env ^. settings . jwtSettings
       :. env ^. settings . cookieSettings
    -- :. authCheck env
       :. EmptyContext

--appMock :: Application
--appMock = serve api (swaggerFront :<|> gargMock :<|> serverStatic)

---------------------------------------------------------------------
api :: Proxy API
api  = Proxy

apiGarg :: Proxy GargAPI
apiGarg  = Proxy
---------------------------------------------------------------------

schemaUiServer :: (Server api ~ Handler Swagger)
        => Swagger -> Server (SwaggerSchemaUI' dir api)
schemaUiServer = swaggerSchemaUIServer


-- Type Family for the Documentation
type family TypeName (x :: *) :: Symbol where
    TypeName Int  = "Int"
    TypeName Text = "Text"
    TypeName x    = GenericTypeName x (Rep x ())

type family GenericTypeName t (r :: *) :: Symbol where
    GenericTypeName t (D1 ('MetaData name mod pkg nt) f x) = name

type Desc t n = Description (AppendSymbol (TypeName t) (AppendSymbol " | " n))


-- | Swagger Specifications
swaggerDoc :: Swagger
swaggerDoc = toSwagger (Proxy :: Proxy GargAPI)
  & info.title       .~ "Gargantext"
  & info.version     .~ "4.0.2" -- TODO same version as Gargantext
  -- & info.base_url     ?~ (URL "http://gargantext.org/")
  & info.description ?~ "REST API specifications"
  -- & tags             .~ Set.fromList [Tag "Garg" (Just "Main perations") Nothing]
  & applyTagsFor (subOperations (Proxy :: Proxy GargAPI)(Proxy :: Proxy GargAPI)) 
                 ["Gargantext" & description ?~ "Main operations"]
  & info.license     ?~ ("AGPLV3 (English) and CECILL (French)" & url ?~ URL urlLicence )
    where
        urlLicence = "https://gitlab.iscpif.fr/gargantext/haskell-gargantext/blob/master/LICENSE"

-- | Output generated @swagger.json@ file for the @'TodoAPI'@.
swaggerWriteJSON :: IO ()
swaggerWriteJSON = BL8.writeFile "swagger.json" (encodePretty swaggerDoc)

portRouteInfo :: PortNumber -> IO ()
portRouteInfo port = do
  T.putStrLn "      ----Main Routes-----      "
  T.putStrLn $ "http://localhost:" <> toUrlPiece port <> "/index.html"
  T.putStrLn $ "http://localhost:" <> toUrlPiece port <> "/swagger-ui"

stopGargantext :: HasRepoSaver env => env -> IO ()
stopGargantext env = do
  T.putStrLn "----- Stopping gargantext -----"
  runReaderT saveRepo env

-- | startGargantext takes as parameters port number and Ini file.
startGargantext :: PortNumber -> FilePath -> IO ()
startGargantext port file = do
  env <- newEnv port file
  portRouteInfo port
  app <- makeApp env
  mid <- makeDevMiddleware
  run port (mid app) `finally` stopGargantext env

{-
startGargantextMock :: PortNumber -> IO ()
startGargantextMock port = do
  portRouteInfo port
  application <- makeMockApp . MockEnv $ FireWall False
  run port application
-}