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

-}

{-# LANGUAGE NoImplicitPrelude #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RankNTypes        #-}

module Gargantext.Database.Flow.Utils
    where

import Data.Map (Map)
import qualified Data.Map as DM
import Gargantext.Prelude
import Gargantext.Database.Schema.Ngrams
import Gargantext.Database.Types.Node (NodeId, Node, NodePoly(..), Hyperdata)
import Gargantext.Database.Utils (Cmd)
import Gargantext.Database.Schema.NodeNgram
import Gargantext.Core.Types.Main (ListType(..), listTypeId)

toMaps :: Hyperdata a => (a -> Map (NgramsT Ngrams) Int) -> [Node a] -> Map (NgramsT Ngrams) (Map NodeId Int)
toMaps fun ns = mapNodeIdNgrams $ documentIdWithNgrams fun ns'
  where
    ns' = map (\(Node nId _ _ _ _ _ json) -> DocumentWithId nId json) ns

mapNodeIdNgrams :: Hyperdata a => [DocumentIdWithNgrams a] -> Map (NgramsT Ngrams) (Map NodeId Int)
mapNodeIdNgrams ds = DM.map (DM.fromListWith (+)) $ DM.fromListWith (<>) xs
  where
    xs  = [(ng, [(nId, i)]) | (nId, n2i') <- n2i ds, (ng, i) <- DM.toList n2i']
    n2i = map (\d -> ((documentId . documentWithId) d, document_ngrams d))


documentIdWithNgrams :: Hyperdata a => (a -> Map (NgramsT Ngrams) Int)
                                     -> [DocumentWithId a] -> [DocumentIdWithNgrams a]
documentIdWithNgrams f = map (\d -> DocumentIdWithNgrams d ((f . documentData) d))


data DocumentWithId a =
     DocumentWithId { documentId   :: NodeId
                    , documentData :: a
                    } deriving (Show)


data DocumentIdWithNgrams a =
     DocumentIdWithNgrams
     { documentWithId  :: DocumentWithId a
     , document_ngrams :: Map (NgramsT Ngrams) Int
     } deriving (Show)

-- | TODO for now, list Type is CandidateList, why ?
insertToNodeNgrams :: Map (NgramsT NgramsIndexed) (Map NodeId Int) -> Cmd err Int
insertToNodeNgrams m = insertNodeNgrams [ NodeNgram nId ((_ngramsId . _ngramsT) ng) ((ngramsTypeId . _ngramsType) ng) (listTypeId CandidateList) (fromIntegral n)
                                        | (ng, nId2int) <- DM.toList m
                                        , (nId, n)      <- DM.toList nId2int
                                        ]