{-# LANGUAGE FlexibleContexts      #-}
{-# LANGUAGE FlexibleInstances     #-}
{-# LANGUAGE LambdaCase            #-}
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE MultiWayIf            #-}
{-# LANGUAGE NoImplicitPrelude     #-}
{-# LANGUAGE OverloadedStrings     #-}
{-# LANGUAGE TemplateHaskell       #-}
{-# LANGUAGE TupleSections         #-}

module Hasura.GraphQL.Schema
  ( mkGCtxMap
  , GCtxMap
  , getGCtx
  , GCtx(..)
  , OpCtx(..)
  , InsCtx(..)
  , InsCtxMap
  , RelationInfoMap
  , isAggFld
  ) where

import           Data.Has

import qualified Data.HashMap.Strict            as Map
import qualified Data.HashSet                   as Set

import qualified Data.Text                      as T
import qualified Language.GraphQL.Draft.Syntax  as G

import           Hasura.GraphQL.Resolve.Context
import           Hasura.GraphQL.Validate.Types

import           Hasura.Prelude
import           Hasura.RQL.DML.Internal        (mkAdminRolePermInfo)
import           Hasura.RQL.Types
import           Hasura.SQL.Types

defaultTypes :: [TypeInfo]
defaultTypes = $(fromSchemaDocQ defaultSchema)

getInsPerm :: TableInfo -> RoleName -> Maybe InsPermInfo
getInsPerm tabInfo role
  | role == adminRole = _permIns $ mkAdminRolePermInfo tabInfo
  | otherwise = Map.lookup role rolePermInfoMap >>= _permIns
  where
    rolePermInfoMap = tiRolePermInfoMap tabInfo

getTabInfo
  :: MonadError QErr m
  => TableCache -> QualifiedTable -> m TableInfo
getTabInfo tc t =
  onNothing (Map.lookup t tc) $
     throw500 $ "table not found: " <>> t

type OpCtxMap = Map.HashMap G.Name OpCtx

data OpCtx
  -- table, req hdrs
  = OCInsert QualifiedTable [T.Text]
  -- tn, filter exp, limit, req hdrs
  | OCSelect QualifiedTable AnnBoolExpSQL (Maybe Int) [T.Text]
  -- tn, filter exp, reqt hdrs
  | OCSelectPkey QualifiedTable AnnBoolExpSQL [T.Text]
  -- tn, filter exp, limit, req hdrs
  | OCSelectAgg QualifiedTable AnnBoolExpSQL (Maybe Int) [T.Text]
  -- tn, filter exp, req hdrs
  | OCUpdate QualifiedTable AnnBoolExpSQL [T.Text]
  -- tn, filter exp, req hdrs
  | OCDelete QualifiedTable AnnBoolExpSQL [T.Text]
  deriving (Show, Eq)

data GCtx
  = GCtx
  { _gTypes     :: !TypeMap
  , _gFields    :: !FieldMap
  , _gOrdByCtx  :: !OrdByCtx
  , _gQueryRoot :: !ObjTyInfo
  , _gMutRoot   :: !(Maybe ObjTyInfo)
  , _gSubRoot   :: !(Maybe ObjTyInfo)
  , _gOpCtxMap  :: !OpCtxMap
  , _gInsCtxMap :: !InsCtxMap
  } deriving (Show, Eq)

instance Has TypeMap GCtx where
  getter = _gTypes
  modifier f ctx = ctx { _gTypes = f $ _gTypes ctx }

data TyAgg
  = TyAgg
  { _taTypes  :: !TypeMap
  , _taFields :: !FieldMap
  , _taOrdBy  :: !OrdByCtx
  } deriving (Show, Eq)

instance Semigroup TyAgg where
  (TyAgg t1 f1 o1) <> (TyAgg t2 f2 o2) =
    TyAgg (Map.union t1 t2) (Map.union f1 f2) (Map.union o1 o2)

instance Monoid TyAgg where
  mempty = TyAgg Map.empty Map.empty Map.empty
  mappend = (<>)

type SelField = Either PGColInfo (RelInfo, Bool, AnnBoolExpSQL, Maybe Int, Bool)

qualTableToName :: QualifiedTable -> G.Name
qualTableToName = G.Name <$> \case
  QualifiedTable (SchemaName "public") tn -> getTableTxt tn
  QualifiedTable sn tn -> getSchemaTxt sn <> "_" <> getTableTxt tn

isValidTableName :: QualifiedTable -> Bool
isValidTableName = isValidName . qualTableToName

isValidField :: FieldInfo -> Bool
isValidField = \case
  FIColumn (PGColInfo col _ _) -> isColEligible col
  FIRelationship (RelInfo rn _ _ remTab _) -> isRelEligible rn remTab
  where
    isColEligible = isValidName . G.Name . getPGColTxt
    isRelEligible rn rt = isValidName (G.Name $ getRelTxt rn)
                          && isValidTableName rt

upsertable :: [TableConstraint] -> Bool -> Bool -> Bool
upsertable constraints isUpsertAllowed view =
  not (null uniqueOrPrimaryCons) && isUpsertAllowed && not view
  where
    uniqueOrPrimaryCons = filter isUniqueOrPrimary constraints

toValidFieldInfos :: FieldInfoMap -> [FieldInfo]
toValidFieldInfos = filter isValidField . Map.elems

validPartitionFieldInfoMap :: FieldInfoMap -> ([PGColInfo], [RelInfo])
validPartitionFieldInfoMap = partitionFieldInfos . toValidFieldInfos

getValidCols :: FieldInfoMap -> [PGColInfo]
getValidCols = fst . validPartitionFieldInfoMap

getValidRels :: FieldInfoMap -> [RelInfo]
getValidRels = snd . validPartitionFieldInfoMap

mkValidConstraints :: [TableConstraint] -> [TableConstraint]
mkValidConstraints = filter isValid
  where
    isValid (TableConstraint _ n) =
      isValidName $ G.Name $ getConstraintTxt n

isRelNullable :: FieldInfoMap -> RelInfo -> Bool
isRelNullable fim ri = isNullable
  where
    lCols = map fst $ riMapping ri
    allCols = getValidCols fim
    lColInfos = getColInfos lCols allCols
    isNullable = any pgiIsNullable lColInfos

numAggOps :: [G.Name]
numAggOps = [ "sum", "avg", "stddev", "stddev_samp", "stddev_pop"
            , "variance", "var_samp", "var_pop"
            ]

compAggOps :: [G.Name]
compAggOps = ["max", "min"]

isAggFld :: G.Name -> Bool
isAggFld = flip elem (numAggOps <> compAggOps)

mkColName :: PGCol -> G.Name
mkColName (PGCol n) = G.Name n

mkRelName :: RelName -> G.Name
mkRelName (RelName r) = G.Name r

mkAggRelName :: RelName -> G.Name
mkAggRelName (RelName r) = G.Name $ r <> "_aggregate"

mkCompExpName :: PGColType -> G.Name
mkCompExpName pgColTy =
  G.Name $ T.pack (show pgColTy) <> "_comparison_exp"

mkCompExpTy :: PGColType -> G.NamedType
mkCompExpTy =
  G.NamedType . mkCompExpName

mkBoolExpName :: QualifiedTable -> G.Name
mkBoolExpName tn =
  qualTableToName tn <> "_bool_exp"

mkBoolExpTy :: QualifiedTable -> G.NamedType
mkBoolExpTy =
  G.NamedType . mkBoolExpName

mkTableTy :: QualifiedTable -> G.NamedType
mkTableTy =
  G.NamedType . qualTableToName

mkTableAggTy :: QualifiedTable -> G.NamedType
mkTableAggTy tn =
  G.NamedType $ qualTableToName tn <> "_aggregate"

mkTableAggFldsTy :: QualifiedTable -> G.NamedType
mkTableAggFldsTy tn =
  G.NamedType $ qualTableToName tn <> "_aggregate_fields"

mkTableColAggFldsTy :: G.Name -> QualifiedTable -> G.NamedType
mkTableColAggFldsTy op tn =
  G.NamedType $ qualTableToName tn <> "_" <> op <> "_fields"

mkTableByPKeyTy :: QualifiedTable -> G.Name
mkTableByPKeyTy tn = qualTableToName tn <> "_by_pk"

mkCompExpInp :: PGColType -> InpObjTyInfo
mkCompExpInp colTy =
  InpObjTyInfo (Just tyDesc) (mkCompExpTy colTy) $ fromInpValL $ concat
  [ map (mk colScalarTy) typedOps
  , map (mk $ G.toLT colScalarTy) listOps
  , bool [] (map (mk $ mkScalarTy PGText) stringOps) isStringTy
  , bool [] (map jsonbOpToInpVal jsonbOps) isJsonbTy
  , [InpValInfo Nothing "_is_null" $ G.TypeNamed $ G.NamedType "Boolean"]
  ]
  where
    tyDesc = mconcat
      [ "expression to compare columns of type "
      , G.Description (T.pack $ show colTy)
      , ". All fields are combined with logical 'AND'."
      ]

    isStringTy = case colTy of
      PGVarchar -> True
      PGText    -> True
      _         -> False

    mk t n = InpValInfo Nothing n $ G.toGT t

    colScalarTy = mkScalarTy colTy
    -- colScalarListTy = GA.GTList colGTy

    typedOps =
       ["_eq", "_neq", "_gt", "_lt", "_gte", "_lte"]

    listOps =
      [ "_in", "_nin" ]

    -- TODO
    -- columnOps =
    --   [ "_ceq", "_cneq", "_cgt", "_clt", "_cgte", "_clte"]

    stringOps =
      [ "_like", "_nlike", "_ilike", "_nilike"
      , "_similar", "_nsimilar"
      ]

    isJsonbTy = case colTy of
      PGJSONB -> True
      _       -> False

    jsonbOpToInpVal (op, ty, desc) = InpValInfo (Just desc) op ty

    jsonbOps =
      [ ( "_contains"
        , G.toGT $ mkScalarTy PGJSONB
        , "does the column contain the given json value at the top level"
        )
      , ( "_contained_in"
        , G.toGT $ mkScalarTy PGJSONB
        , "is the column contained in the given json value"
        )
      , ( "_has_key"
        , G.toGT $ mkScalarTy PGText
        , "does the string exist as a top-level key in the column"
        )
      , ( "_has_keys_any"
        , G.toGT $ G.toLT $ G.toNT $ mkScalarTy PGText
        , "do any of these strings exist as top-level keys in the column"
        )
      , ( "_has_keys_all"
        , G.toGT $ G.toLT $ G.toNT $ mkScalarTy PGText
        , "do all of these strings exist as top-level keys in the column"
        )
      ]

mkPGColFld :: PGColInfo -> ObjFldInfo
mkPGColFld (PGColInfo colName colTy isNullable) =
  ObjFldInfo Nothing n Map.empty ty
  where
    n  = G.Name $ getPGColTxt colName
    ty = bool notNullTy nullTy isNullable
    scalarTy = mkScalarTy colTy
    notNullTy = G.toGT $ G.toNT scalarTy
    nullTy = G.toGT scalarTy

-- where: table_bool_exp
-- limit: Int
-- offset: Int
mkSelArgs :: QualifiedTable -> [InpValInfo]
mkSelArgs tn =
  [ InpValInfo (Just whereDesc) "where" $ G.toGT $ mkBoolExpTy tn
  , InpValInfo (Just limitDesc) "limit" $ G.toGT $ mkScalarTy PGInteger
  , InpValInfo (Just offsetDesc) "offset" $ G.toGT $ mkScalarTy PGInteger
  , InpValInfo (Just orderByDesc) "order_by" $ G.toGT $ G.toLT $ G.toNT $
    mkOrdByTy tn
  ]
  where
    whereDesc   = "filter the rows returned"
    limitDesc   = "limit the nuber of rows returned"
    offsetDesc  = "skip the first n rows. Use only with order_by"
    orderByDesc = "sort the rows by one or more columns"

fromInpValL :: [InpValInfo] -> Map.HashMap G.Name InpValInfo
fromInpValL = mapFromL _iviName

{-

array_relationship(
  where: remote_table_bool_exp
  limit: Int
  offset: Int
):  [remote_table!]!
array_relationship_aggregate(
  where: remote_table_bool_exp
  limit: Int
  offset: Int
):  remote_table_aggregate!
object_relationship: remote_table

-}
mkRelFld
  :: Bool
  -> RelInfo
  -> Bool
  -> [ObjFldInfo]
mkRelFld allowAgg (RelInfo rn rTy _ remTab isManual) isNullable = case rTy of
  ArrRel -> bool [arrRelFld] [arrRelFld, aggArrRelFld] allowAgg
  ObjRel -> [objRelFld]
  where
    objRelFld = ObjFldInfo (Just "An object relationship")
      (G.Name $ getRelTxt rn) Map.empty objRelTy
    objRelTy = bool (G.toGT $ G.toNT relTabTy) (G.toGT relTabTy) isObjRelNullable
    isObjRelNullable = isManual || isNullable
    relTabTy = mkTableTy remTab

    arrRelFld =
      ObjFldInfo (Just "An array relationship") (G.Name $ getRelTxt rn)
      (fromInpValL $ mkSelArgs remTab) arrRelTy
    arrRelTy = G.toGT $ G.toNT $ G.toLT $ G.toNT $ mkTableTy remTab
    aggArrRelFld = ObjFldInfo (Just "An aggregated array relationship")
      (mkAggRelName rn) (fromInpValL $ mkSelArgs remTab) $
      G.toGT $ G.toNT $ mkTableAggTy remTab

{-
type table {
  col1: colty1
  .
  .
  rel1: relty1
}
-}
mkTableObj
  :: QualifiedTable
  -> [SelField]
  -> ObjTyInfo
mkTableObj tn allowedFlds =
  mkObjTyInfo (Just desc) (mkTableTy tn) $ mapFromL _fiName flds
  where
    flds = concatMap (either (pure . mkPGColFld) mkRelFld') allowedFlds
    mkRelFld' (relInfo, allowAgg, _, _, isNullable) =
      mkRelFld allowAgg relInfo isNullable
    desc = G.Description $ "columns and relationships of " <>> tn

{-
type table_aggregate {
  agg: table_aggregate_fields
  nodes: [table!]!
}
-}
mkTableAggObj
  :: QualifiedTable -> ObjTyInfo
mkTableAggObj tn =
  mkObjTyInfo (Just desc) (mkTableAggTy tn) $ mapFromL _fiName
  [aggFld, nodesFld]
  where
    desc = G.Description $
      "aggregated selection of " <>> tn

    aggFld = ObjFldInfo Nothing "aggregate" Map.empty $ G.toGT $
             mkTableAggFldsTy tn
    nodesFld = ObjFldInfo Nothing "nodes" Map.empty $ G.toGT $
               G.toNT $ G.toLT $ G.toNT $ mkTableTy tn

{-
type table_aggregate_fields{
  count: Int
  sum: table_sum_fields
  avg: table_avg_fields
  stddev: table_stddev_fields
  stddev_pop: table_stddev_pop_fields
  variance: table_variance_fields
  var_pop: table_var_pop_fields
  max: table_max_fields
  min: table_min_fields
}
-}
mkTableAggFldsObj
  :: QualifiedTable -> [PGCol] -> [PGCol] -> ObjTyInfo
mkTableAggFldsObj tn numCols compCols =
  mkObjTyInfo (Just desc) (mkTableAggFldsTy tn) $ mapFromL _fiName $
  countFld : (numFlds <> compFlds)
  where
    desc = G.Description $
      "aggregate fields of " <>> tn

    countFld = ObjFldInfo Nothing "count" countParams $ G.toGT $
               mkScalarTy PGInteger

    countParams = fromInpValL [countColInpVal, distinctInpVal]

    countColInpVal = InpValInfo Nothing "columns" $ G.toGT $
                     G.toLT $ G.toNT $ mkSelColumnInpTy tn
    distinctInpVal = InpValInfo Nothing "distinct" $ G.toGT $
                     mkScalarTy PGBoolean

    numFlds = bool (map mkColOpFld numAggOps) [] $ null numCols
    compFlds = bool (map mkColOpFld compAggOps) [] $ null compCols

    mkColOpFld op = ObjFldInfo Nothing op Map.empty $ G.toGT $
                    mkTableColAggFldsTy op tn

{-
type table_<agg-op>_fields{
   num_col: Int
   .        .
   .        .
}
-}
mkTableColAggFldsObj
  :: QualifiedTable
  -> G.Name
  -> (PGColType -> G.NamedType)
  -> [PGColInfo]
  -> ObjTyInfo
mkTableColAggFldsObj tn op f cols =
  mkObjTyInfo (Just desc) (mkTableColAggFldsTy op tn) $ mapFromL _fiName $
  map mkColObjFld cols
  where
    desc = G.Description $ "aggregate " <> G.unName op <> " on columns"

    mkColObjFld c = ObjFldInfo Nothing (G.Name $ getPGColTxt $ pgiName c)
                    Map.empty $ G.toGT $ f $ pgiType c

{-

table(
  where: table_bool_exp
  limit: Int
  offset: Int
):  [table!]!

-}
mkSelFld
  :: QualifiedTable
  -> ObjFldInfo
mkSelFld tn =
  ObjFldInfo (Just desc) fldName args ty
  where
    desc    = G.Description $ "fetch data from the table: " <>> tn
    fldName = qualTableToName tn
    args    = fromInpValL $ mkSelArgs tn
    ty      = G.toGT $ G.toNT $ G.toLT $ G.toNT $ mkTableTy tn

{-
table_by_pk(
  col1: value1!,
  .     .
  .     .
  coln: valuen!
): table
-}
mkSelFldPKey
  :: QualifiedTable -> [PGColInfo]
  -> ObjFldInfo
mkSelFldPKey tn cols =
  ObjFldInfo (Just desc) fldName args ty
  where
    desc = G.Description $ "fetch data from the table: " <> tn
           <<> " using primary key columns"
    fldName = mkTableByPKeyTy tn
    args = fromInpValL $ map colInpVal cols
    ty = G.toGT $ mkTableTy tn
    colInpVal (PGColInfo n typ _) =
      InpValInfo Nothing (mkColName n) $ G.toGT $ G.toNT $ mkScalarTy typ

{-

table_aggregate(
  where: table_bool_exp
  limit: Int
  offset: Int
): table_aggregate!

-}
mkAggSelFld
  :: QualifiedTable
  -> ObjFldInfo
mkAggSelFld tn =
  ObjFldInfo (Just desc) fldName args ty
  where
    desc = G.Description $ "fetch aggregated fields from the table: "
           <>> tn
    fldName = qualTableToName tn <> "_aggregate"
    args = fromInpValL $ mkSelArgs tn
    ty = G.toGT $ G.toNT $ mkTableAggTy tn

-- table_mutation_response
mkMutRespTy :: QualifiedTable -> G.NamedType
mkMutRespTy tn =
  G.NamedType $ qualTableToName tn <> "_mutation_response"

{-
type table_mutation_response {
  affected_rows: Int!
  returning: [table!]!
}
-}
mkMutRespObj
  :: QualifiedTable
  -> Bool -- is sel perm defined
  -> ObjTyInfo
mkMutRespObj tn sel =
  mkObjTyInfo (Just objDesc) (mkMutRespTy tn) $ mapFromL _fiName
  $ affectedRowsFld : bool [] [returningFld] sel
  where
    objDesc = G.Description $
      "response of any mutation on the table " <>> tn
    affectedRowsFld =
      ObjFldInfo (Just desc) "affected_rows" Map.empty $
      G.toGT $ G.toNT $ mkScalarTy PGInteger
      where
        desc = "number of affected rows by the mutation"
    returningFld =
      ObjFldInfo (Just desc) "returning" Map.empty $
      G.toGT $ G.toNT $ G.toLT $ G.toNT $ mkTableTy tn
      where
        desc = "data of the affected rows by the mutation"

mkBoolExpInp
  :: QualifiedTable
  -- the fields that are allowed
  -> [SelField]
  -> InpObjTyInfo
mkBoolExpInp tn fields =
  InpObjTyInfo (Just desc) boolExpTy $ Map.fromList
  [(_iviName inpVal, inpVal) | inpVal <- inpValues]
  where
    desc = G.Description $
      "Boolean expression to filter rows from the table " <> tn <<>
      ". All fields are combined with a logical 'AND'."

    -- the type of this boolean expression
    boolExpTy = mkBoolExpTy tn

    -- all the fields of this input object
    inpValues = combinators <> map mkFldExpInp fields

    mk n ty = InpValInfo Nothing n $ G.toGT ty

    boolExpListTy = G.toLT boolExpTy

    combinators =
      [ mk "_not" boolExpTy
      , mk "_and" boolExpListTy
      , mk "_or"  boolExpListTy
      ]

    mkFldExpInp = \case
      Left (PGColInfo colName colTy _) ->
        mk (mkColName colName) (mkCompExpTy colTy)
      Right (RelInfo relName _ _ remTab _, _, _, _, _) ->
        mk (G.Name $ getRelTxt relName) (mkBoolExpTy remTab)

mkPGColInp :: PGColInfo -> InpValInfo
mkPGColInp (PGColInfo colName colTy _) =
  InpValInfo Nothing (G.Name $ getPGColTxt colName) $
  G.toGT $ mkScalarTy colTy

-- table_set_input
mkUpdSetTy :: QualifiedTable -> G.NamedType
mkUpdSetTy tn =
  G.NamedType $ qualTableToName tn <> "_set_input"

{-
input table_set_input {
  col1: colty1
  .
  .
  coln: coltyn
}
-}
mkUpdSetInp
  :: QualifiedTable -> [PGColInfo] -> InpObjTyInfo
mkUpdSetInp tn cols  =
  InpObjTyInfo (Just desc) (mkUpdSetTy tn) $ fromInpValL $
  map mkPGColInp cols
  where
    desc = G.Description $
      "input type for updating data in table " <>> tn

-- table_inc_input
mkUpdIncTy :: QualifiedTable -> G.NamedType
mkUpdIncTy tn =
  G.NamedType $ qualTableToName tn <> "_inc_input"

{-
input table_inc_input {
  integer-col1: int
  .
  .
  integer-coln: int
}
-}

mkUpdIncInp
  :: QualifiedTable -> Maybe [PGColInfo] -> Maybe InpObjTyInfo
mkUpdIncInp tn = maybe Nothing mkType
  where
    mkType cols = let intCols = onlyIntCols cols
                      incObjTy =
                        InpObjTyInfo (Just desc) (mkUpdIncTy tn) $
                        fromInpValL $ map mkPGColInp intCols
                  in bool (Just incObjTy) Nothing $ null intCols
    desc = G.Description $
      "input type for incrementing integer columne in table " <>> tn

-- table_<json-op>_input
mkJSONOpTy :: QualifiedTable -> G.Name -> G.NamedType
mkJSONOpTy tn op =
  G.NamedType $ qualTableToName tn <> op <> "_input"

-- json ops are _concat, _delete_key, _delete_elem, _delete_at_path
{-
input table_concat_input {
  jsonb-col1: json
  .
  .
  jsonb-coln: json
}
-}

{-
input table_delete_key_input {
  jsonb-col1: string
  .
  .
  jsonb-coln: string
}
-}

{-
input table_delete_elem_input {
  jsonb-col1: int
  .
  .
  jsonb-coln: int
}
-}

{-
input table_delete_at_path_input {
  jsonb-col1: [string]
  .
  .
  jsonb-coln: [string]
}
-}

-- jsonb operators and descriptions
prependOp :: G.Name
prependOp = "_prepend"

prependDesc :: G.Description
prependDesc = "prepend existing jsonb value of filtered columns with new jsonb value"

appendOp :: G.Name
appendOp = "_append"

appendDesc :: G.Description
appendDesc = "append existing jsonb value of filtered columns with new jsonb value"

deleteKeyOp :: G.Name
deleteKeyOp = "_delete_key"

deleteKeyDesc :: G.Description
deleteKeyDesc = "delete key/value pair or string element."
                <> " key/value pairs are matched based on their key value"

deleteElemOp :: G.Name
deleteElemOp = "_delete_elem"

deleteElemDesc :: G.Description
deleteElemDesc = "delete the array element with specified index (negative integers count from the end)."
                 <> " throws an error if top level container is not an array"

deleteAtPathOp :: G.Name
deleteAtPathOp = "_delete_at_path"

deleteAtPathDesc :: G.Description
deleteAtPathDesc = "delete the field or element with specified path"
                   <> " (for JSON arrays, negative integers count from the end)"

mkUpdJSONOpInp
  :: QualifiedTable -> [PGColInfo] -> [InpObjTyInfo]
mkUpdJSONOpInp tn cols = bool inpObjs [] $ null jsonbCols
  where
    jsonbCols = onlyJSONBCols cols
    jsonbColNames = map pgiName jsonbCols

    inpObjs = [ prependInpObj, appendInpObj, deleteKeyInpObj
              , deleteElemInpObj, deleteAtPathInpObj
              ]

    appendInpObj =
      InpObjTyInfo (Just appendDesc) (mkJSONOpTy tn appendOp) $
      fromInpValL $ map mkPGColInp jsonbCols

    prependInpObj =
      InpObjTyInfo (Just prependDesc) (mkJSONOpTy tn prependOp) $
      fromInpValL $ map mkPGColInp jsonbCols

    deleteKeyInpObj =
      InpObjTyInfo (Just deleteKeyDesc) (mkJSONOpTy tn deleteKeyOp) $
      fromInpValL $ map deleteKeyInpVal jsonbColNames
    deleteKeyInpVal c = InpValInfo Nothing (G.Name $ getPGColTxt c) $
      G.toGT $ G.NamedType "String"

    deleteElemInpObj =
      InpObjTyInfo (Just deleteElemDesc) (mkJSONOpTy tn deleteElemOp) $
      fromInpValL $ map deleteElemInpVal jsonbColNames
    deleteElemInpVal c = InpValInfo Nothing (G.Name $ getPGColTxt c) $
      G.toGT $ G.NamedType "Int"

    deleteAtPathInpObj =
      InpObjTyInfo (Just deleteAtPathDesc) (mkJSONOpTy tn deleteAtPathOp) $
      fromInpValL $ map deleteAtPathInpVal jsonbColNames
    deleteAtPathInpVal c = InpValInfo Nothing (G.Name $ getPGColTxt c) $
      G.toGT $ G.toLT $ G.NamedType "String"

{-

update_table(
  where : table_bool_exp!
  _set  : table_set_input
  _inc  : table_inc_input
  _concat: table_concat_input
  _delete_key: table_delete_key_input
  _delete_elem: table_delete_elem_input
  _delete_path_at: table_delete_path_at_input
): table_mutation_response

-}

mkIncInpVal :: QualifiedTable -> [PGColInfo] -> Maybe InpValInfo
mkIncInpVal tn cols = bool (Just incArg) Nothing $ null intCols
  where
    intCols = onlyIntCols cols
    incArgDesc = "increments the integer columns with given value of the filtered values"
    incArg =
      InpValInfo (Just incArgDesc) "_inc" $ G.toGT $ mkUpdIncTy tn

mkJSONOpInpVals :: QualifiedTable -> [PGColInfo] -> [InpValInfo]
mkJSONOpInpVals tn cols = bool jsonbOpArgs [] $ null jsonbCols
  where
    jsonbCols = onlyJSONBCols cols
    jsonbOpArgs = [appendArg, prependArg, deleteKeyArg, deleteElemArg, deleteAtPathArg]

    appendArg =
      InpValInfo (Just appendDesc) appendOp $ G.toGT $ mkJSONOpTy tn appendOp

    prependArg =
      InpValInfo (Just prependDesc) prependOp $ G.toGT $ mkJSONOpTy tn prependOp

    deleteKeyArg =
      InpValInfo (Just deleteKeyDesc) deleteKeyOp $
      G.toGT $ mkJSONOpTy tn deleteKeyOp

    deleteElemArg =
      InpValInfo (Just deleteElemDesc) deleteElemOp $
      G.toGT $ mkJSONOpTy tn deleteElemOp

    deleteAtPathArg =
      InpValInfo (Just deleteAtPathDesc) deleteAtPathOp $
      G.toGT $ mkJSONOpTy tn deleteAtPathOp

mkUpdMutFld
  :: QualifiedTable -> [PGColInfo] -> ObjFldInfo
mkUpdMutFld tn cols =
  ObjFldInfo (Just desc) fldName (fromInpValL inputValues) $
  G.toGT $ mkMutRespTy tn
  where
    inputValues = [filterArg, setArg] <> incArg
                  <> mkJSONOpInpVals tn cols
    desc = G.Description $ "update data of the table: " <>> tn

    fldName = "update_" <> qualTableToName tn

    filterArgDesc = "filter the rows which have to be updated"
    filterArg =
      InpValInfo (Just filterArgDesc) "where" $ G.toGT $
      G.toNT $ mkBoolExpTy tn

    setArgDesc = "sets the columns of the filtered rows to the given values"
    setArg =
      InpValInfo (Just setArgDesc) "_set" $ G.toGT $ mkUpdSetTy tn

    incArg = maybeToList $ mkIncInpVal tn cols

{-

delete_table(
  where : table_bool_exp!
): table_mutation_response

-}

mkDelMutFld
  :: QualifiedTable -> ObjFldInfo
mkDelMutFld tn =
  ObjFldInfo (Just desc) fldName (fromInpValL [filterArg]) $
  G.toGT $ mkMutRespTy tn
  where
    desc = G.Description $ "delete data from the table: " <>> tn

    fldName = "delete_" <> qualTableToName tn

    filterArgDesc = "filter the rows which have to be deleted"
    filterArg =
      InpValInfo (Just filterArgDesc) "where" $ G.toGT $
      G.toNT $ mkBoolExpTy tn

-- table_insert_input
mkInsInpTy :: QualifiedTable -> G.NamedType
mkInsInpTy tn =
  G.NamedType $ qualTableToName tn <> "_insert_input"

-- table_obj_rel_insert_input
mkObjInsInpTy :: QualifiedTable -> G.NamedType
mkObjInsInpTy tn =
  G.NamedType $ qualTableToName tn <> "_obj_rel_insert_input"

-- table_arr_rel_insert_input
mkArrInsInpTy :: QualifiedTable -> G.NamedType
mkArrInsInpTy tn =
  G.NamedType $ qualTableToName tn <> "_arr_rel_insert_input"


-- table_on_conflict
mkOnConflictInpTy :: QualifiedTable -> G.NamedType
mkOnConflictInpTy tn =
  G.NamedType $ qualTableToName tn <> "_on_conflict"

-- table_constraint
mkConstraintInpTy :: QualifiedTable -> G.NamedType
mkConstraintInpTy tn =
  G.NamedType $ qualTableToName tn <> "_constraint"

-- table_update_column
mkUpdColumnInpTy :: QualifiedTable -> G.NamedType
mkUpdColumnInpTy tn =
  G.NamedType $ qualTableToName tn <> "_update_column"

--table_select_column
mkSelColumnInpTy :: QualifiedTable -> G.NamedType
mkSelColumnInpTy tn =
  G.NamedType $ qualTableToName tn <> "_select_column"
{-
input table_obj_rel_insert_input {
  data: table_insert_input!
  on_conflict: table_on_conflict
}

-}

{-
input table_arr_rel_insert_input {
  data: [table_insert_input!]!
  on_conflict: table_on_conflict
}

-}

mkRelInsInps
  :: QualifiedTable -> Bool -> [InpObjTyInfo]
mkRelInsInps tn upsertAllowed = [objRelInsInp, arrRelInsInp]
  where
    onConflictInpVal =
      InpValInfo Nothing "on_conflict" $ G.toGT $ mkOnConflictInpTy tn

    onConflictInp = bool [] [onConflictInpVal] upsertAllowed

    objRelDesc = G.Description $
      "input type for inserting object relation for remote table " <>> tn

    objRelDataInp = InpValInfo Nothing "data" $ G.toGT $
                    G.toNT $ mkInsInpTy tn
    objRelInsInp = InpObjTyInfo (Just objRelDesc) (mkObjInsInpTy tn)
                   $ fromInpValL $ objRelDataInp : onConflictInp

    arrRelDesc = G.Description $
      "input type for inserting array relation for remote table " <>> tn

    arrRelDataInp = InpValInfo Nothing "data" $ G.toGT $
                    G.toNT $ G.toLT $ G.toNT $ mkInsInpTy tn
    arrRelInsInp = InpObjTyInfo (Just arrRelDesc) (mkArrInsInpTy tn)
                   $ fromInpValL $ arrRelDataInp : onConflictInp

{-

input table_insert_input {
  col1: colty1
  .
  .
  coln: coltyn
}

-}

mkInsInp
  :: QualifiedTable -> InsCtx -> InpObjTyInfo
mkInsInp tn insCtx =
  InpObjTyInfo (Just desc) (mkInsInpTy tn) $ fromInpValL $
  map mkPGColInp insCols <> relInps
  where
    desc = G.Description $
      "input type for inserting data into table " <>> tn
    cols = icColumns insCtx
    setCols = Map.keys $ icSet insCtx
    insCols = flip filter cols $ \ci -> pgiName ci `notElem` setCols
    relInfoMap = icRelations insCtx

    relInps = flip map (Map.toList relInfoMap) $
      \(relName, relInfo) ->
         let rty = riType relInfo
             remoteQT = riRTable relInfo
         in case rty of
            ObjRel -> InpValInfo Nothing (G.Name $ getRelTxt relName) $
                      G.toGT $ mkObjInsInpTy remoteQT
            ArrRel -> InpValInfo Nothing (G.Name $ getRelTxt relName) $
                      G.toGT $ mkArrInsInpTy remoteQT

{-

input table_on_conflict {
  action: conflict_action
  constraint: table_constraint!
  update_columns: [table_column!]
}

-}

mkOnConflictInp :: QualifiedTable -> InpObjTyInfo
mkOnConflictInp tn =
  InpObjTyInfo (Just desc) (mkOnConflictInpTy tn) $ fromInpValL
  [actionInpVal, constraintInpVal, updateColumnsInpVal]
  where
    desc = G.Description $
      "on conflict condition type for table " <>> tn

    actionDesc = "action when conflict occurs (deprecated)"

    actionInpVal = InpValInfo (Just actionDesc) (G.Name "action") $
      G.toGT $ G.NamedType "conflict_action"

    constraintInpVal = InpValInfo Nothing (G.Name "constraint") $
      G.toGT $ G.toNT $ mkConstraintInpTy tn

    updateColumnsInpVal = InpValInfo Nothing (G.Name "update_columns") $
      G.toGT $ G.toLT $ G.toNT $ mkUpdColumnInpTy tn
{-

insert_table(
  objects: [table_insert_input!]!
  on_conflict: table_on_conflict
  ): table_mutation_response!
-}

mkInsMutFld
  :: QualifiedTable -> Bool -> ObjFldInfo
mkInsMutFld tn isUpsertable =
  ObjFldInfo (Just desc) fldName (fromInpValL inputVals) $
  G.toGT $ mkMutRespTy tn
  where
    inputVals = catMaybes [Just objectsArg , onConflictInpVal]
    desc = G.Description $
      "insert data into the table: " <>> tn

    fldName = "insert_" <> qualTableToName tn

    objsArgDesc = "the rows to be inserted"
    objectsArg =
      InpValInfo (Just objsArgDesc) "objects" $ G.toGT $
      G.toNT $ G.toLT $ G.toNT $ mkInsInpTy tn

    onConflictInpVal = bool Nothing (Just onConflictArg) isUpsertable

    onConflictDesc = "on conflict condition"
    onConflictArg =
      InpValInfo (Just onConflictDesc) "on_conflict" $ G.toGT $ mkOnConflictInpTy tn

mkConstriantTy :: QualifiedTable -> [TableConstraint] -> EnumTyInfo
mkConstriantTy tn cons = enumTyInfo
  where
    enumTyInfo = EnumTyInfo (Just desc) (mkConstraintInpTy tn) $
                 mapFromL _eviVal $ map (mkConstraintEnumVal . tcName ) cons

    desc = G.Description $
      "unique or primary key constraints on table " <>> tn

    mkConstraintEnumVal (ConstraintName n) =
      EnumValInfo (Just "unique or primary key constraint")
      (G.EnumValue $ G.Name n) False

mkColumnEnumVal :: PGCol -> EnumValInfo
mkColumnEnumVal (PGCol col) =
  EnumValInfo (Just "column name") (G.EnumValue $ G.Name col) False

mkUpdColumnTy :: QualifiedTable -> [PGCol] -> EnumTyInfo
mkUpdColumnTy tn cols = enumTyInfo
  where
    enumTyInfo = EnumTyInfo (Just desc) (mkUpdColumnInpTy tn) $
                 mapFromL _eviVal $ map mkColumnEnumVal cols

    desc = G.Description $
      "update columns of table " <>> tn

mkSelColumnTy :: QualifiedTable -> [PGCol] -> EnumTyInfo
mkSelColumnTy tn cols = enumTyInfo
  where
    enumTyInfo = EnumTyInfo (Just desc) (mkSelColumnInpTy tn) $
                 mapFromL _eviVal $ map mkColumnEnumVal cols

    desc = G.Description $
      "select columns of table " <>> tn

mkConflictActionTy :: EnumTyInfo
mkConflictActionTy = EnumTyInfo (Just desc) ty $ mapFromL _eviVal
                     [enumValIgnore, enumValUpdate]
  where
    desc = G.Description "conflict action"
    ty = G.NamedType "conflict_action"
    enumValIgnore = EnumValInfo (Just "ignore the insert on this row")
                    (G.EnumValue "ignore") False
    enumValUpdate = EnumValInfo (Just "update the row with the given values")
                    (G.EnumValue "update") False

ordByTy :: G.NamedType
ordByTy = G.NamedType "order_by"

ordByEnumTy :: EnumTyInfo
ordByEnumTy =
  EnumTyInfo (Just desc) ordByTy $ mapFromL _eviVal $
  map mkEnumVal enumVals
  where
    desc = G.Description "column ordering options"
    mkEnumVal (n, d) =
      EnumValInfo (Just d) (G.EnumValue n) False
    enumVals =
      [ ( "asc"
        , "in the ascending order, nulls last"
        ),
        ( "asc_nulls_last"
        , "in the ascending order, nulls last"
        ),
        ( "asc_nulls_first"
        , "in the ascending order, nulls first"
        ),
        ( "desc"
        , "in the descending order, nulls first"
        ),
        ( "desc_nulls_first"
        , "in the descending order, nulls first"
        ),
        ( "desc_nulls_last"
        , "in the descending order, nulls last"
        )
      ]

mkOrdByTy :: QualifiedTable -> G.NamedType
mkOrdByTy tn =
  G.NamedType $ qualTableToName tn <> "_order_by"

{-
input table_order_by {
  col1: order_by
  col2: order_by
  .     .
  .     .
  coln: order_by
  obj-rel: <remote-table>_order_by
}
-}

mkOrdByInpObj
  :: QualifiedTable -> [SelField] -> (InpObjTyInfo, OrdByCtx)
mkOrdByInpObj tn selFlds = (inpObjTy, ordByCtx)
  where
    inpObjTy =
      InpObjTyInfo (Just desc) namedTy $ fromInpValL $
      map mkColOrdBy pgCols <> map mkObjRelOrdBy objRels

    namedTy = mkOrdByTy tn
    desc = G.Description $
      "ordering options when selecting data from " <>> tn

    pgCols = lefts selFlds
    objRels = flip filter (rights selFlds) $ \(ri, _, _, _, _) ->
      riType ri == ObjRel

    mkColOrdBy ci = InpValInfo Nothing (mkColName $ pgiName ci) $
                    G.toGT ordByTy
    mkObjRelOrdBy (ri, _, _, _, _) =
      InpValInfo Nothing (mkRelName $ riName ri) $
      G.toGT $ mkOrdByTy $ riRTable ri

    ordByCtx = Map.singleton namedTy $ Map.fromList $
               colOrdBys <> relOrdBys
    colOrdBys = flip map pgCols $ \ci ->
                                    ( mkColName $ pgiName ci
                                    , OBIPGCol ci
                                    )
    relOrdBys = flip map objRels $ \(ri, _, fltr, _, _) ->
                                     ( mkRelName $ riName ri
                                     , OBIRel ri fltr
                                     )

newtype RootFlds
  = RootFlds
  { _taMutation :: Map.HashMap G.Name (OpCtx, Either ObjFldInfo ObjFldInfo)
  } deriving (Show, Eq)

instance Semigroup RootFlds where
  (RootFlds m1) <> (RootFlds m2)
    = RootFlds (Map.union m1 m2)

instance Monoid RootFlds where
  mempty = RootFlds Map.empty
  mappend  = (<>)

mkOnConflictTypes
  :: QualifiedTable -> [TableConstraint] -> [PGCol] -> Bool -> [TypeInfo]
mkOnConflictTypes tn c cols =
  bool [] tyInfos
  where
    tyInfos = [ TIEnum mkConflictActionTy
              , TIEnum $ mkConstriantTy tn constraints
              , TIEnum $ mkUpdColumnTy tn cols
              , TIInpObj $ mkOnConflictInp tn
              ]
    constraints = filter isUniqueOrPrimary c

mkGCtxRole'
  :: QualifiedTable
  -- insert perm
  -> Maybe (InsCtx, Bool)
  -- select permission
  -> Maybe (Bool, [SelField])
  -- update cols
  -> Maybe [PGColInfo]
  -- delete cols
  -> Maybe ()
  -- primary key columns
  -> [PGColInfo]
  -- constraints
  -> [TableConstraint]
  -> Maybe ViewInfo
  -- all columns
  -> [PGCol]
  -> TyAgg
mkGCtxRole' tn insPermM selPermM updColsM delPermM pkeyCols constraints viM allCols =
  TyAgg (mkTyInfoMap allTypes) fieldMap ordByCtx

  where

    ordByCtx = fromMaybe Map.empty ordByCtxM
    upsertPerm = or $ fmap snd insPermM
    isUpsertable = upsertable constraints upsertPerm $ isJust viM
    onConflictTypes = mkOnConflictTypes tn constraints allCols isUpsertable
    jsonOpTys = fromMaybe [] updJSONOpInpObjTysM
    relInsInpObjTys = maybe [] (map TIInpObj) $
                      mutHelper viIsInsertable relInsInpObjsM

    allTypes = relInsInpObjTys <> onConflictTypes <> jsonOpTys
               <> queryTypes <> aggQueryTypes <> mutationTypes

    queryTypes = catMaybes
      [ TIInpObj <$> boolExpInpObjM
      , TIInpObj <$> ordByInpObjM
      , TIObj <$> selObjM
      ]
    aggQueryTypes = map TIObj aggObjs

    mutationTypes = catMaybes
      [ TIInpObj <$> mutHelper viIsInsertable insInpObjM
      , TIInpObj <$> mutHelper viIsUpdatable updSetInpObjM
      , TIInpObj <$> mutHelper viIsUpdatable updIncInpObjM
      , TIObj <$> mutRespObjM
      , TIEnum <$> selColInpTyM
      ]
    mutHelper f objM = bool Nothing objM $ isMutable f viM

    fieldMap = Map.unions $ catMaybes
               [ insInpObjFldsM, updSetInpObjFldsM, boolExpInpObjFldsM
               , selObjFldsM, Just selByPKeyObjFlds
               ]

    -- helper
    mkColFldMap ty cols = Map.fromList $ flip map cols $
      \c -> ((ty, mkColName $ pgiName c), Left c)

    insCtxM = fst <$> insPermM
    insColsM = icColumns <$> insCtxM
    -- insert input type
    insInpObjM = mkInsInp tn <$> insCtxM
    -- column fields used in insert input object
    insInpObjFldsM = mkColFldMap (mkInsInpTy tn) <$> insColsM
    -- relationship input objects
    relInsInpObjsM = const (mkRelInsInps tn isUpsertable) <$> insCtxM
    -- update set input type
    updSetInpObjM = mkUpdSetInp tn <$> updColsM
    -- update increment input type
    updIncInpObjM = mkUpdIncInp tn updColsM
    -- update json operator input type
    updJSONOpInpObjsM = mkUpdJSONOpInp tn <$> updColsM
    updJSONOpInpObjTysM = map TIInpObj <$> updJSONOpInpObjsM
    -- fields used in set input object
    updSetInpObjFldsM = mkColFldMap (mkUpdSetTy tn) <$> updColsM

    selFldsM = snd <$> selPermM
    selColsM = (map pgiName . lefts) <$> selFldsM
    selColInpTyM = mkSelColumnTy tn <$> selColsM
    -- boolexp input type
    boolExpInpObjM = case selFldsM of
      Just selFlds  -> Just $ mkBoolExpInp tn selFlds
      -- no select permission
      Nothing ->
        -- but update/delete is defined
        if isJust updColsM || isJust delPermM
        then Just $ mkBoolExpInp tn []
        else Nothing

    -- helper
    mkFldMap ty = Map.fromList . concatMap (mkFld ty)
    mkFld ty = \case
      Left ci -> [((ty, mkColName $ pgiName ci), Left ci)]
      Right (ri, allowAgg, perm, lim, _) ->
        let relFld = ( (ty, G.Name $ getRelTxt $ riName ri)
                     , Right (ri, False, perm, lim)
                     )
            aggRelFld = ( (ty, mkAggRelName $ riName ri)
                        , Right (ri, True, perm, lim)
                        )
        in case riType ri of
          ObjRel -> [relFld]
          ArrRel -> bool [relFld] [relFld, aggRelFld] allowAgg

    -- the fields used in bool exp
    boolExpInpObjFldsM = mkFldMap (mkBoolExpTy tn) <$> selFldsM

    -- mut resp obj
    mutRespObjM =
      if isMut
      then Just $ mkMutRespObj tn $ isJust selFldsM
      else Nothing

    isMut = (isJust insColsM || isJust updColsM || isJust delPermM)
            && any (`isMutable` viM) [viIsInsertable, viIsUpdatable, viIsDeletable]

    -- table obj
    selObjM = mkTableObj tn <$> selFldsM
    -- aggregate objs
    aggObjs = case selPermM of
      Just (True, selFlds) ->
        let numCols = (map pgiName . getNumCols) selFlds
            compCols = (map pgiName . getCompCols) selFlds
        in [ mkTableAggObj tn
           , mkTableAggFldsObj tn numCols compCols
           ] <> mkColAggFldsObjs selFlds
      _ -> []
    getNumCols = onlyNumCols . lefts
    getCompCols = onlyComparableCols . lefts
    onlyFloat = const $ mkScalarTy PGFloat

    mkTypeMaker "sum" = mkScalarTy
    mkTypeMaker _     = onlyFloat

    mkColAggFldsObjs flds =
      let numCols = getNumCols flds
          compCols = getCompCols flds
          mkNumObjFld n = mkTableColAggFldsObj tn n (mkTypeMaker n) numCols
          mkCompObjFld n = mkTableColAggFldsObj tn n mkScalarTy compCols
          numFldsObjs = bool (map mkNumObjFld numAggOps) [] $ null numCols
          compFldsObjs = bool (map mkCompObjFld compAggOps) [] $ null compCols
      in numFldsObjs <> compFldsObjs
    -- the fields used in table object
    selObjFldsM = mkFldMap (mkTableTy tn) <$> selFldsM
    -- the field used in table_by_pkey object
    selByPKeyObjFlds = Map.fromList $ flip map pkeyCols $
      \pgi@(PGColInfo col ty _) -> ((mkScalarTy ty, mkColName col), Left pgi)

    ordByInpCtxM = mkOrdByInpObj tn <$> selFldsM
    (ordByInpObjM, ordByCtxM) = case ordByInpCtxM of
      Just (a, b) -> (Just a, Just b)
      Nothing     -> (Nothing, Nothing)


getRootFldsRole'
  :: QualifiedTable
  -> [PGCol]
  -> [TableConstraint]
  -> FieldInfoMap
  -> Maybe ([T.Text], Bool) -- insert perm
  -> Maybe (AnnBoolExpSQL, Maybe Int, [T.Text], Bool) -- select filter
  -> Maybe ([PGCol], AnnBoolExpSQL, [T.Text]) -- update filter
  -> Maybe (AnnBoolExpSQL, [T.Text]) -- delete filter
  -> Maybe ViewInfo
  -> RootFlds
getRootFldsRole' tn primCols constraints fields insM selM updM delM viM =
  RootFlds mFlds
  where
    mFlds = mapFromL (either _fiName _fiName . snd) $ catMaybes
            [ mutHelper viIsInsertable getInsDet insM
            , mutHelper viIsUpdatable getUpdDet updM
            , mutHelper viIsDeletable getDelDet delM
            , getSelDet <$> selM, getSelAggDet selM
            , getPKeySelDet selM $ getColInfos primCols colInfos
            ]
    mutHelper f getDet mutM =
      bool Nothing (getDet <$> mutM) $ isMutable f viM
    colInfos = fst $ validPartitionFieldInfoMap fields
    getInsDet (hdrs, upsertPerm) =
      let isUpsertable = upsertable constraints upsertPerm $ isJust viM
      in ( OCInsert tn hdrs
         , Right $ mkInsMutFld tn isUpsertable
         )
    getUpdDet (updCols, updFltr, hdrs) =
      ( OCUpdate tn updFltr hdrs
      , Right $ mkUpdMutFld tn $ getColInfos updCols colInfos
      )
    getDelDet (delFltr, hdrs) =
      (OCDelete tn delFltr hdrs, Right $ mkDelMutFld tn)
    getSelDet (selFltr, pLimit, hdrs, _) =
      (OCSelect tn selFltr pLimit hdrs, Left $ mkSelFld tn)

    getSelAggDet (Just (selFltr, pLimit, hdrs, True)) = Just
      (OCSelectAgg tn selFltr pLimit hdrs, Left $ mkAggSelFld tn)
    getSelAggDet _ = Nothing

    getPKeySelDet Nothing _ = Nothing
    getPKeySelDet _ [] = Nothing
    getPKeySelDet (Just (selFltr, _, hdrs, _)) pCols = Just
      (OCSelectPkey tn selFltr hdrs, Left $ mkSelFldPKey tn pCols)

-- getRootFlds
--   :: TableCache
--   -> Map.HashMap RoleName RootFlds
-- getRootFlds tables =
--   foldr (Map.unionWith mappend . getRootFldsTable) Map.empty $
--   Map.elems tables

-- gets all the selectable fields (cols and rels) of a
-- table for a role

getSelPermission :: TableInfo -> RoleName -> Maybe SelPermInfo
getSelPermission tabInfo role =
  Map.lookup role (tiRolePermInfoMap tabInfo) >>= _permSel

getSelPerm
  :: (MonadError QErr m)
  => TableCache
  -- all the fields of a table
  -> FieldInfoMap
  -- role and its permission
  -> RoleName -> SelPermInfo
  -> m (Bool, [SelField])
getSelPerm tableCache fields role selPermInfo = do
  selFlds <- fmap catMaybes $ forM (toValidFieldInfos fields) $ \case
    FIColumn pgColInfo ->
      return $ fmap Left $ bool Nothing (Just pgColInfo) $
      Set.member (pgiName pgColInfo) allowedCols
    FIRelationship relInfo -> do
      remTableInfo <- getTabInfo tableCache $ riRTable relInfo
      let remTableSelPermM = getSelPermission remTableInfo role
      return $ flip fmap remTableSelPermM $
        \rmSelPermM -> Right ( relInfo
                             , spiAllowAgg rmSelPermM
                             , spiFilter rmSelPermM
                             , spiLimit rmSelPermM
                             , isRelNullable fields relInfo
                             )
  return (spiAllowAgg selPermInfo, selFlds)
  where
    allowedCols = spiCols selPermInfo

mkInsCtx
  :: MonadError QErr m
  => RoleName
  -> TableCache -> FieldInfoMap -> InsPermInfo -> m InsCtx
mkInsCtx role tableCache fields insPermInfo = do
  relTupsM <- forM rels $ \relInfo -> do
    let remoteTable = riRTable relInfo
        relName = riName relInfo
    remoteTableInfo <- getTabInfo tableCache remoteTable
    let insPermM = getInsPerm remoteTableInfo role
        viewInfoM = tiViewInfo remoteTableInfo
    return $ bool Nothing (Just (relName, relInfo)) $
      isInsertable insPermM viewInfoM

  let relInfoMap = Map.fromList $ catMaybes relTupsM
  return $ InsCtx iView cols setCols relInfoMap
  where
    cols = getValidCols fields
    rels = getValidRels fields
    iView = ipiView insPermInfo
    setCols = ipiSet insPermInfo

    isInsertable Nothing _          = False
    isInsertable (Just _) viewInfoM = isMutable viIsInsertable viewInfoM

mkAdminInsCtx
  :: MonadError QErr m
  => QualifiedTable -> TableCache -> FieldInfoMap -> m InsCtx
mkAdminInsCtx tn tc fields = do
  relTupsM <- forM rels $ \relInfo -> do
    let remoteTable = riRTable relInfo
        relName = riName relInfo
    remoteTableInfo <- getTabInfo tc remoteTable
    let viewInfoM = tiViewInfo remoteTableInfo
    return $ bool Nothing (Just (relName, relInfo)) $
      isMutable viIsInsertable viewInfoM

  return $ InsCtx tn cols Map.empty $ Map.fromList $ catMaybes relTupsM
  where
    cols = getValidCols fields
    rels = getValidRels fields

mkGCtxRole
  :: (MonadError QErr m)
  => TableCache
  -> QualifiedTable
  -> FieldInfoMap
  -> [PGCol]
  -> [TableConstraint]
  -> Maybe ViewInfo
  -> RoleName
  -> RolePermInfo
  -> m (TyAgg, RootFlds, InsCtxMap)
mkGCtxRole tableCache tn fields pCols constraints viM role permInfo = do
  selPermM <- mapM (getSelPerm tableCache fields role) $ _permSel permInfo
  tabInsCtxM <- forM (_permIns permInfo) $ \ipi -> do
    tic <- mkInsCtx role tableCache fields ipi
    return (tic, ipiAllowUpsert ipi)
  let updColsM = filterColInfos . upiCols <$> _permUpd permInfo
      tyAgg = mkGCtxRole' tn tabInsCtxM selPermM updColsM
              (void $ _permDel permInfo) pColInfos constraints viM allCols
      rootFlds = getRootFldsRole tn pCols constraints fields viM permInfo
      insCtxMap = maybe Map.empty (Map.singleton tn) $ fmap fst tabInsCtxM
  return (tyAgg, rootFlds, insCtxMap)
  where
    colInfos = getValidCols fields
    allCols = map pgiName colInfos
    pColInfos = getColInfos pCols colInfos
    filterColInfos allowedSet =
      filter ((`Set.member` allowedSet) . pgiName) colInfos

getRootFldsRole
  :: QualifiedTable
  -> [PGCol]
  -> [TableConstraint]
  -> FieldInfoMap
  -> Maybe ViewInfo
  -> RolePermInfo
  -> RootFlds
getRootFldsRole tn pCols constraints fields viM (RolePermInfo insM selM updM delM) =
  getRootFldsRole' tn pCols constraints fields
  (mkIns <$> insM) (mkSel <$> selM)
  (mkUpd <$> updM) (mkDel <$> delM)
  viM
  where
    mkIns i = (ipiRequiredHeaders i, ipiAllowUpsert i)
    mkSel s = ( spiFilter s, spiLimit s
              , spiRequiredHeaders s, spiAllowAgg s
              )
    mkUpd u = ( Set.toList $ upiCols u
              , upiFilter u
              , upiRequiredHeaders u
              )
    mkDel d = (dpiFilter d, dpiRequiredHeaders d)

mkGCtxMapTable
  :: (MonadError QErr m)
  => TableCache
  -> TableInfo
  -> m (Map.HashMap RoleName (TyAgg, RootFlds, InsCtxMap))
mkGCtxMapTable tableCache (TableInfo tn _ fields rolePerms constraints pkeyCols viewInfo _) = do
  m <- Map.traverseWithKey
       (mkGCtxRole tableCache tn fields pkeyCols validConstraints viewInfo) rolePerms
  adminInsCtx <- mkAdminInsCtx tn tableCache fields
  let adminCtx = mkGCtxRole' tn (Just (adminInsCtx, True))
                 (Just (True, selFlds)) (Just colInfos) (Just ())
                 pkeyColInfos validConstraints viewInfo allCols
      adminInsCtxMap = Map.singleton tn adminInsCtx
  return $ Map.insert adminRole (adminCtx, adminRootFlds, adminInsCtxMap) m
  where
    validConstraints = mkValidConstraints constraints
    colInfos = getValidCols fields
    allCols = map pgiName colInfos
    pkeyColInfos = getColInfos pkeyCols colInfos
    selFlds = flip map (toValidFieldInfos fields) $ \case
      FIColumn pgColInfo     -> Left pgColInfo
      FIRelationship relInfo -> Right (relInfo, True, noFilter, Nothing, isRelNullable fields relInfo)
    adminRootFlds =
      getRootFldsRole' tn pkeyCols validConstraints fields
      (Just ([], True)) (Just (noFilter, Nothing, [], True))
      (Just (allCols, noFilter, [])) (Just (noFilter, []))
      viewInfo

noFilter :: AnnBoolExpSQL
noFilter = annBoolExpTrue

mkScalarTyInfo :: PGColType -> ScalarTyInfo
mkScalarTyInfo = ScalarTyInfo Nothing

type GCtxMap = Map.HashMap RoleName GCtx

mkGCtxMap
  :: (MonadError QErr m)
  => TableCache -> m (Map.HashMap RoleName GCtx)
mkGCtxMap tableCache = do
  typesMapL <- mapM (mkGCtxMapTable tableCache) $
               filter tableFltr $ Map.elems tableCache
  let typesMap = foldr (Map.unionWith mappend) Map.empty typesMapL
  return $ flip Map.map typesMap $ \(ty, flds, insCtxMap) ->
    mkGCtx ty flds insCtxMap
  where
    tableFltr ti = not (tiSystemDefined ti)
                   && isValidTableName (tiName ti)

mkGCtx :: TyAgg -> RootFlds -> InsCtxMap -> GCtx
mkGCtx (TyAgg tyInfos fldInfos ordByEnums) (RootFlds flds) insCtxMap =
  let queryRoot = mkObjTyInfo (Just "query root") (G.NamedType "query_root") $
                  mapFromL _fiName (schemaFld:typeFld:qFlds)
      colTys    = Set.toList $ Set.fromList $ map pgiType $
                  lefts $ Map.elems fldInfos
      scalarTys = map (TIScalar . mkScalarTyInfo) colTys
      compTys   = map (TIInpObj . mkCompExpInp) colTys
      ordByEnumTyM = bool (Just ordByEnumTy) Nothing $ null qFlds
      allTys    = Map.union tyInfos $ mkTyInfoMap $
                  catMaybes [ Just $ TIObj queryRoot
                            , TIObj <$> mutRootM
                            , TIObj <$> subRootM
                            , TIEnum <$> ordByEnumTyM
                            ] <>
                  scalarTys <> compTys <> defaultTypes
  -- for now subscription root is query root
  in GCtx allTys fldInfos ordByEnums queryRoot mutRootM (Just queryRoot)
     (Map.map fst flds) insCtxMap
  where

    mkMutRoot =
      mkObjTyInfo (Just "mutation root") (G.NamedType "mutation_root") .
      mapFromL _fiName

    mutRootM = bool (Just $ mkMutRoot mFlds) Nothing $ null mFlds

    mkSubRoot =
      mkObjTyInfo (Just "subscription root") (G.NamedType "subscription_root") .
      mapFromL _fiName

    subRootM = bool (Just $ mkSubRoot qFlds) Nothing $ null qFlds

    (qFlds, mFlds) = partitionEithers $ map snd $ Map.elems flds

    schemaFld = ObjFldInfo Nothing "__schema" Map.empty $ G.toGT $
                G.toNT $ G.NamedType "__Schema"

    typeFld = ObjFldInfo Nothing "__type" typeFldArgs $ G.toGT $
              G.NamedType "__Type"
      where
        typeFldArgs = mapFromL _iviName [
          InpValInfo (Just "name of the type") "name"
          $ G.toGT $ G.toNT $ G.NamedType "String"
          ]

getGCtx :: RoleName -> Map.HashMap RoleName GCtx -> GCtx
getGCtx rn =
  fromMaybe (mkGCtx mempty mempty mempty) . Map.lookup rn