{-|
Module      : Gargantext.Database.Query.Table.Node.Children
Description : Main requests of Node to the database
Copyright   : (c) CNRS, 2017-Present
License     : AGPL + CECILL v3
Maintainer  : team@gargantext.org
Stability   : experimental
Portability : POSIX
-}

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

{-# LANGUAGE Arrows                 #-}
{-# LANGUAGE FlexibleInstances      #-}
{-# LANGUAGE FlexibleContexts       #-}
{-# LANGUAGE RankNTypes             #-}

module Gargantext.Database.Query.Table.Node.Children
  where

import Control.Arrow (returnA)
import Data.Proxy
import Gargantext.Core.Types
import Gargantext.Database.Query.Filter
import Gargantext.Database.Query.Table.Node
import Gargantext.Database.Query.Table.NodeNode
import Gargantext.Database.Query.Table.Node.Contact (HyperdataContact)
import Gargantext.Database.Admin.Config (nodeTypeId)
import Gargantext.Database.Admin.Types.Node (pgNodeId)
import Gargantext.Database.Prelude
import Gargantext.Database.Schema.Node
import Opaleye

getAllDocuments :: ParentId -> Cmd err (TableResult (Node HyperdataDocument))
getAllDocuments pId = getAllChildren pId (Proxy :: Proxy HyperdataDocument)
                                         (Just NodeDocument)

getAllContacts :: ParentId -> Cmd err (TableResult (Node HyperdataContact))
getAllContacts pId = getAllChildren pId (Proxy :: Proxy HyperdataContact)
                                        (Just NodeContact)

getAllChildren :: JSONB a
               => ParentId
               -> proxy a
               -> Maybe NodeType
               -> Cmd err (NodeTableResult a)
getAllChildren pId p maybeNodeType = getChildren pId p maybeNodeType Nothing Nothing

getChildren :: JSONB a
            => ParentId
            -> proxy a
            -> Maybe NodeType
            -> Maybe Offset
            -> Maybe Limit
            -> Cmd err (NodeTableResult a)
getChildren pId _ maybeNodeType maybeOffset maybeLimit = do
  docs <- runOpaQuery
          $ limit' maybeLimit $ offset' maybeOffset
          $ orderBy (asc _node_id)
          $ query

  docCount <- runCountOpaQuery query

  pure $ TableResult { tr_docs = docs, tr_count = docCount }

  where
    query = selectChildren pId maybeNodeType

selectChildren :: ParentId
               -> Maybe NodeType
               -> Query NodeRead
selectChildren parentId maybeNodeType = proc () -> do
    row@(Node nId typeName _ parent_id _ _ _) <- queryNodeTable -< ()
    (NodeNode n1id n2id _ _) <- queryNodeNodeTable -< ()

    let nodeType = maybe 0 nodeTypeId maybeNodeType
    restrict -< typeName  .== pgInt4 nodeType

    restrict -< (.||) (parent_id .== (pgNodeId parentId))
                      ( (.&&) (n1id .== pgNodeId parentId)
                              (n2id .== nId))
    returnA -< row