module Hasura.RQL.IR.Update
  ( AnnUpd,
    AnnUpdG (..),
    UpdOpExpG (..),
    updateOperatorText,
  )
where

import Data.Kind (Type)
import Hasura.Prelude
import Hasura.RQL.IR.BoolExp
import Hasura.RQL.IR.Returning
import Hasura.RQL.Types.Backend
import Hasura.RQL.Types.Column
import Hasura.SQL.Backend

data AnnUpdG (b :: BackendType) (r :: BackendType -> Type) v = AnnUpd
  { uqp1Table :: !(TableName b),
    uqp1OpExps :: ![(Column b, UpdOpExpG v)],
    uqp1Where :: !(AnnBoolExp b v, AnnBoolExp b v),
    uqp1Check :: !(AnnBoolExp b v),
    -- we don't prepare the arguments for returning
    -- however the session variable can still be
    -- converted as desired
    uqp1Output :: !(MutationOutputG b r v),
    uqp1AllCols :: ![ColumnInfo b]
  }
  deriving (Functor, Foldable, Traversable)

type AnnUpd b = AnnUpdG b (Const Void) (SQLExpression b)

data UpdOpExpG v
  = UpdSet !v
  | UpdInc !v
  | UpdAppend !v
  | UpdPrepend !v
  | UpdDeleteKey !v
  | UpdDeleteElem !v
  | UpdDeleteAtPath ![v]
  deriving (Functor, Foldable, Traversable, Generic, Data)

-- NOTE: This function can be improved, because we use
-- the literal values defined below in the 'updateOperators'
-- function in 'Hasura.GraphQL.Schema.Mutation'. It would
-- be nice if we could avoid duplicating the string literal
-- values
updateOperatorText :: UpdOpExpG a -> Text
updateOperatorText (UpdSet _) = "_set"
updateOperatorText (UpdInc _) = "_inc"
updateOperatorText (UpdAppend _) = "_append"
updateOperatorText (UpdPrepend _) = "_prepend"
updateOperatorText (UpdDeleteKey _) = "_delete_key"
updateOperatorText (UpdDeleteElem _) = "_delete_elem"
updateOperatorText (UpdDeleteAtPath _) = "_delete_at_path"