module GraqlQuerySpec
  ( spec
  ) where

import           Control.Exception (Exception, displayException)
import           Data.Either       (isLeft)
import           Data.Map          (member)
import           Data.Text         (pack)
import           Env
import           Grakn
import           Test.Hspec

aKnowledgeBaseContainingTypesAndInstances :: IO Client
aKnowledgeBaseContainingTypesAndInstances = do
  client <- givenAKnowledgeBase
  envDefine "person sub entity, has name; name sub attribute, datatype string;"
  envInsert "$alice isa person, has name \"Alice\";"
  return client

givenAKnowledgeBase :: IO Client
givenAKnowledgeBase = Client defaultUrl <$> envKeyspace

x :: Var
x = var $ pack "x"

spec :: Spec
spec =
  before aKnowledgeBaseContainingTypesAndInstances $
  describe
    "As a Grakn Developer, I should be able to interact with a Grakn knowledge base using Graql queries" $ do
    it "Valid Define Query" $ \client -> do
      response <- execute client "define $x label dog sub entity;"
      typeIsInTheKB "dog"
      response `hasVar` x
    it "Redundant Define Query" $ \client -> do
      response <- execute client "define $x label person sub entity;"
      response `hasVar` x
    it "Valid Insert Query" $ \client -> do
      response <- execute client "insert $bob isa person, has name \"Bob\";"
      instanceIsInTheKB "name" "Bob"
      response `hasAnswers` 1
    it "Invalid Insert Query" $ \client -> do
      response <-
        execute client "insert $dunstan isa dog, has name \"Dunstan\";"
      isAnError response
    it "Get Query With Empty Response" $ \client -> do
      response <- execute client "match $x isa person, has name \"Precy\"; get;"
      response `hasAnswers` 0
    it "Get Query With Non-Empty Response" $ \client -> do
      response <- execute client "match $x isa person, has name \"Alice\"; get;"
      response `hasAnswers` 1
    it "Aggregate Ask Query With False Response" $ \client -> do
      response <- execute client "match $x has name \"Precy\"; aggregate ask;"
      response `is` AskResult False
    it "Aggregate Ask Query With True Response" $ \client -> do
      response <- execute client "match $x has name \"Alice\"; aggregate ask;"
      response `is` AskResult True
    it "Aggregate Query" $ \client -> do
      response <- execute client "match $x isa person; aggregate count;"
      response `is` CountResult 1
    it "Compute Query" $ \client -> do
      response <- execute client "compute count in person;"
      response `is` CountResult 1
    it "Successful Undefine Query" $ \client -> do
      envDefine "dog sub entity;"
      response <- execute client "undefine dog sub entity;"
      response `is` DeleteResult
    it "Unsuccessful Undefine Query" $ \client -> do
      response <- execute client "undefine person sub entity;"
      isAnError response
    it "Delete Query for non Existent Concept" $ \client -> do
      response <- execute client "match $x has name \"Precy\"; delete $x;"
      response `is` DeleteResult
    it "Inference on by default" $ \client -> do
      envDefine
        "weird-rule sub rule when { $person has name \"Alice\"; } then { $person has name \"A\"; };"
      response <- execute client "match $x has name \"A\"; get;"
      response `hasAnswers` 1
    it "Inference can be disabled" $ \client -> do
      envDefine
        "weird-rule sub rule when { $person has name \"Alice\"; } then { $person has name \"A\"; };"
      response <-
        execute_ Options {infer = False} client "match $x has name \"A\"; get;"
      response `hasAnswers` 0

is :: (Exception e, Show a, Eq a) => Either e a -> a -> Expectation
response `is` expected =
  case response of
    Right answer -> answer `shouldBe` expected
    Left err     -> expectationFailure (displayException err)

isAnError :: Either t a -> Expectation
isAnError response = isLeft response `shouldBe` True

typeIsInTheKB :: String -> Expectation
typeIsInTheKB label = do
  isIn <- envCheckType label
  isIn `shouldBe` True

instanceIsInTheKB :: String -> String -> Expectation
instanceIsInTheKB res val = do
  isIn <- envCheckInstance res val
  isIn `shouldBe` True

hasAnswers :: Exception e => Either e Result -> Int -> Expectation
response `hasAnswers` n =
  case response of
    Right (AnswersResult answers) -> length answers `shouldBe` n
    Left err -> expectationFailure (displayException err)
    x -> expectationFailure (show x)

hasVar :: Exception e => Either e Result -> Var -> Expectation
response `hasVar` var =
  case response of
    Right (AnswerResult answer) -> member var answer `shouldBe` True
    Left err                    -> expectationFailure (displayException err)
    x                           -> expectationFailure (show x)