{-# LANGUAGE DataKinds #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RankNTypes #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}

module Network.HTTP.ReqSpec (spec) where

import Control.Exception
import Control.Monad (forM_)
import Control.Monad.Trans.Control
import Data.Aeson (ToJSON (..), Value (..), object, (.=))
import Data.Aeson qualified as A
import Data.Aeson.KeyMap qualified as Aeson.KeyMap
import Data.ByteString qualified as B
import Data.ByteString.Lazy qualified as BL
import Data.Functor.Identity (runIdentity)
import Data.Maybe (fromJust)
import Data.Proxy
import Data.Text (Text)
import Data.Text qualified as T
import Data.Text.Encoding qualified as T
import Data.Text.IO qualified as TIO
import Network.HTTP.Client qualified as L
import Network.HTTP.Client.MultipartFormData qualified as LM
import Network.HTTP.Req hiding (req)
import Network.HTTP.Req qualified as Req
import Network.HTTP.Types qualified as Y
import Test.Hspec
import Test.QuickCheck

spec :: Spec
spec = do
  describe "exception throwing on non-2xx status codes" $
    it "throws indeed for non-2xx" $
      req GET (httpbin /: "foo") NoReqBody ignoreResponse mempty
        `shouldThrow` selector404

  describe "exception throwing on non-2xx status codes (Req monad)" $
    it "throws indeed for non-2xx" $
      asIO . runReq defaultHttpConfig $
        liftBaseWith $ \run ->
          run (req GET (httpbin /: "foo") NoReqBody ignoreResponse mempty)
            `shouldThrow` selector404

  describe "response check via httpConfigCheckResponse" $
    context "if it's set to always throw" $
      it "throws indeed" $
        blindlyThrowing (req GET httpbin NoReqBody ignoreResponse mempty)
          `shouldThrow` anyException

  describe "isStatusCodeException" $
    it "extracts non-2xx response" $
      req GET (httpbin /: "foo") NoReqBody ignoreResponse mempty
        `shouldThrow` selector404ByStatusCodeException

  describe "receiving user-agent header back" $
    it "works" $ do
      r <-
        req
          GET
          (httpbin /: "user-agent")
          NoReqBody
          jsonResponse
          (header "user-agent" "Req")
      responseBody r
        `shouldBe` object
          ["user-agent" .= ("Req" :: Text)]
      responseStatusCode r `shouldBe` 200
      responseStatusMessage r `shouldBe` "OK"

  describe "receiving request headers back" $
    it "works" $ do
      r <-
        req
          GET
          (httpbin /: "headers")
          NoReqBody
          jsonResponse
          (header "Foo" "bar" <> header "Baz" "quux")
      stripFunnyHeaders (responseBody r)
        `shouldBe` object
          [ "headers"
              .= object
                [ "Accept-Encoding" .= ("gzip" :: Text),
                  "Foo" .= ("bar" :: Text),
                  "Baz" .= ("quux" :: Text)
                ]
          ]
      responseStatusCode r `shouldBe` 200
      responseStatusMessage r `shouldBe` "OK"

  describe "receiving GET data back" $
    it "works" $ do
      r <- req GET (httpbin /: "get") NoReqBody jsonResponse mempty
      (stripFunnyHeaders . stripOrigin) (responseBody r)
        `shouldBe` object
          [ "args" .= emptyObject,
            "url" .= ("http://localhost:1234/get" :: Text),
            "headers"
              .= object
                [ "Accept-Encoding" .= ("gzip" :: Text)
                ]
          ]
      responseHeader r "Content-Type" `shouldBe` return "application/json"
      responseStatusCode r `shouldBe` 200
      responseStatusMessage r `shouldBe` "OK"

  describe "receiving POST JSON data back" $
    it "works" $ do
      let text = "foo" :: Text
          reflected = reflectJSON text
      r <- req POST (httpbin /: "post") (ReqBodyJson text) jsonResponse mempty
      (stripFunnyHeaders . stripOrigin) (responseBody r)
        `shouldBe` object
          [ "args" .= emptyObject,
            "json" .= text,
            "data" .= reflected,
            "url" .= ("http://localhost:1234/post" :: Text),
            "headers"
              .= object
                [ "Content-Type" .= ("application/json; charset=utf-8" :: Text),
                  "Accept-Encoding" .= ("gzip" :: Text),
                  "Content-Length" .= show (T.length reflected)
                ],
            "files" .= emptyObject,
            "form" .= emptyObject
          ]
      responseHeader r "Content-Type" `shouldBe` return "application/json"
      responseStatusCode r `shouldBe` 200
      responseStatusMessage r `shouldBe` "OK"

  describe "receiving POST data back (multipart form data)" $
    it "works" $ do
      body <-
        reqBodyMultipart
          [ LM.partBS "foo" "foo data!",
            LM.partBS "bar" "bar data!"
          ]
      r <- req POST (httpbin /: "post") body jsonResponse mempty
      let contentType = fromJust (getRequestContentType body)
      (stripFunnyHeaders . stripOrigin) (responseBody r)
        `shouldBe` object
          [ "args" .= emptyObject,
            "json" .= Null,
            "data" .= ("" :: Text),
            "url" .= ("http://localhost:1234/post" :: Text),
            "headers"
              .= object
                [ "Content-Type" .= T.decodeUtf8 contentType,
                  "Accept-Encoding" .= ("gzip" :: Text),
                  "Content-Length" .= ("242" :: Text)
                ],
            "files" .= emptyObject,
            "form"
              .= object
                [ "foo" .= ("foo data!" :: Text),
                  "bar" .= ("bar data!" :: Text)
                ]
          ]
      responseHeader r "Content-Type" `shouldBe` return "application/json"
      responseStatusCode r `shouldBe` 200
      responseStatusMessage r `shouldBe` "OK"

  describe "receiving PATCHed file back" $
    it "works" $ do
      let file :: FilePath
          file = "httpbin-data/robots.txt"
      contents <- TIO.readFile file
      r <- req PATCH (httpbin /: "patch") (ReqBodyFile file) jsonResponse mempty
      (stripFunnyHeaders . stripOrigin) (responseBody r)
        `shouldBe` object
          [ "args" .= emptyObject,
            "json" .= Null,
            "data" .= contents,
            "url" .= ("http://localhost:1234/patch" :: Text),
            "headers"
              .= object
                [ "Accept-Encoding" .= ("gzip" :: Text),
                  "Content-Length" .= show (T.length contents)
                ],
            "files" .= emptyObject,
            "form" .= emptyObject
          ]
      responseHeader r "Content-Type" `shouldBe` return "application/json"
      responseStatusCode r `shouldBe` 200
      responseStatusMessage r `shouldBe` "OK"

  describe "receiving PUT form URL-encoded data back" $
    it "works" $ do
      let params =
            "foo" =: ("bar" :: Text)
              <> "baz" =: (5 :: Int)
              <> queryFlag "quux"
      r <- req PUT (httpbin /: "put") (ReqBodyUrlEnc params) jsonResponse mempty
      (stripFunnyHeaders . stripOrigin) (responseBody r)
        `shouldBe` object
          [ "args" .= emptyObject,
            "json" .= Null,
            "data" .= ("" :: Text),
            "url" .= ("http://localhost:1234/put" :: Text),
            "headers"
              .= object
                [ "Content-Type" .= ("application/x-www-form-urlencoded" :: Text),
                  "Accept-Encoding" .= ("gzip" :: Text),
                  "Content-Length" .= ("18" :: Text)
                ],
            "files" .= emptyObject,
            "form"
              .= object
                [ "foo" .= ("bar" :: Text),
                  "baz" .= ("5" :: Text),
                  "quux" .= ("" :: Text)
                ]
          ]
      responseHeader r "Content-Type" `shouldBe` return "application/json"
      responseStatusCode r `shouldBe` 200
      responseStatusMessage r `shouldBe` "OK"

  -- TODO /delete

  describe "receiving UTF-8 encoded Unicode data" $
    it "works" $ do
      r <-
        req
          GET
          (httpbin /: "encoding" /: "utf8")
          NoReqBody
          bsResponse
          mempty
      utf8data <- B.readFile "httpbin-data/utf8.html"
      responseBody r `shouldBe` utf8data
      responseStatusCode r `shouldBe` 200
      responseStatusMessage r `shouldBe` "OK"

  -- TODO /gzip
  -- TODO /deflate

  describe "retrying" $
    it "retries as many times as specified" $ do
      -- FIXME We no longer can count retries because all the functions
      -- responsible for controlling retrying are pure now.
      let status = 408 :: Int
      r <-
        prepareForShit $
          req
            GET
            (httpbin /: "status" /~ status)
            NoReqBody
            ignoreResponse
            mempty
      responseStatusCode r `shouldBe` status

  -- forM_ [101..102] checkStatusCode
  forM_ [200 .. 208] checkStatusCode
  -- forM_ [300..308] checkStatusCode
  forM_ [400 .. 431] checkStatusCode
  forM_ [500 .. 511] checkStatusCode

  -- TODO /response-headers
  -- TODO /redirect

  describe "redirects" $
    it "follows redirects" $ do
      r <-
        req
          GET
          (httpbin /: "redirect-to")
          NoReqBody
          ignoreResponse
          ("url" =: ("https://httpbin.org" :: Text))
      responseStatusCode r `shouldBe` 200
      responseStatusMessage r `shouldBe` "OK"

  -- TODO /relative-redicet
  -- TODO /absolute-redirect
  -- TODO /cookies

  describe "basicAuth" $ do
    let user, password :: Text
        user = "Scooby"
        password = "Doo"
    context "when we do not send appropriate basic auth data" $
      it "fails with 401" $ do
        r <-
          prepareForShit $
            req
              GET
              (httpbin /: "basic-auth" /~ user /~ password)
              NoReqBody
              ignoreResponse
              mempty
        responseStatusCode r `shouldBe` 401
        responseStatusMessage r `shouldBe` "UNAUTHORIZED"
    context "when we provide appropriate basic auth data" $
      it "succeeds" $ do
        r <-
          req
            GET
            (httpbin /: "basic-auth" /~ user /~ password)
            NoReqBody
            ignoreResponse
            (basicAuthUnsafe (T.encodeUtf8 user) (T.encodeUtf8 password))
        responseStatusCode r `shouldBe` 200
        responseStatusMessage r `shouldBe` "OK"

  -- TODO /hidden-basic-auth
  -- TODO /digest-auth
  -- TODO /stream
  -- TODO /delay
  -- TODO /drip
  -- TODO /range
  -- TODO /html

  describe "robots.txt" $
    it "works" $ do
      r <- req GET (httpbin /: "robots.txt") NoReqBody bsResponse mempty
      robots <- B.readFile "httpbin-data/robots.txt"
      responseBody r `shouldBe` robots
      responseStatusCode r `shouldBe` 200
      responseStatusMessage r `shouldBe` "OK"

  -- TODO /deny
  -- TODO /cache

  describe "getting random bytes" $ do
    it "works" $
      property $ \n' -> do
        let n :: Word
            n = getSmall n'
        r <-
          req
            GET
            (httpbin /: "bytes" /~ n)
            NoReqBody
            lbsResponse
            mempty
        responseBody r `shouldSatisfy` ((== n) . fromIntegral . BL.length)
        responseStatusCode r `shouldBe` 200
        responseStatusMessage r `shouldBe` "OK"
    context "when we try to interpret 1000 random bytes as JSON" $
      it "throws correct exception" $ do
        let selector :: HttpException -> Bool
            selector (JsonHttpException _) = True
            selector _ = False
            n :: Int
            n = 1000
        req
          GET
          (httpbin /: "bytes" /~ n)
          NoReqBody
          (Proxy :: Proxy (JsonResponse Value))
          mempty
          `shouldThrow` selector

  describe "streaming random bytes" $
    it "works" $
      property $ \n' -> do
        let n :: Word
            n = getSmall n'
        r <-
          req
            GET
            (httpbin /: "stream-bytes" /~ n)
            NoReqBody
            bsResponse
            mempty
        responseBody r `shouldSatisfy` ((== n) . fromIntegral . B.length)
        responseStatusCode r `shouldBe` 200
        responseStatusMessage r `shouldBe` "OK"

-- TODO /links
-- TODO /image
-- TODO /image/png
-- TODO /image/jpeg
-- TODO /image/webp
-- TODO /image/svg
-- TODO /forms/post
-- TODO /xml

----------------------------------------------------------------------------
-- Instances

instance MonadHttp IO where
  handleHttpException = throwIO

----------------------------------------------------------------------------
-- Helpers

-- | Run a request with such settings that it does not signal errors.
prepareForShit :: Req a -> IO a
prepareForShit = runReq defaultHttpConfig {httpConfigCheckResponse = noNoise}
  where
    noNoise _ _ _ = Nothing

-- | Run a request with such settings that it throws on any response.
blindlyThrowing :: Req a -> IO a
blindlyThrowing = runReq defaultHttpConfig {httpConfigCheckResponse = doit}
  where
    doit _ _ = error "Oops!"

-- | 'Url' representing <https://httpbin.org>.
httpbin :: Url 'Http
httpbin = http "localhost"

req ::
  ( MonadHttp m,
    HttpMethod method,
    HttpBody body,
    HttpResponse response,
    HttpBodyAllowed (AllowsBody method) (ProvidesBody body)
  ) =>
  method ->
  Url scheme ->
  body ->
  Proxy response ->
  Option scheme ->
  m response
req method url body responseProxy options =
  Req.req method url body responseProxy (options <> defaultOptions)

-- | Options to apply by default.
defaultOptions :: Option scheme
defaultOptions = port 1234

-- | Remove “origin” field from JSON value. Origin may change, we don't want
-- to depend on that.
stripOrigin :: Value -> Value
stripOrigin (Object m) = Object (Aeson.KeyMap.delete "origin" m)
stripOrigin value = value

-- | Remove funny headers that might break the tests.
stripFunnyHeaders :: Value -> Value
stripFunnyHeaders = \case
  Object m ->
    Object
      ( runIdentity
          ( Aeson.KeyMap.alterF
              (pure . fmap stripFunnyHeaders')
              "headers"
              m
          )
      )
  value -> value

-- | Similar to 'stripFunnyHeaders', but acts directly on the argument
-- without trying to access its "headers" field.
stripFunnyHeaders' :: Value -> Value
stripFunnyHeaders' = \case
  Object p ->
    Object $
      Aeson.KeyMap.filterWithKey
        (\k _ -> k `elem` whitelistedHeaders)
        p
  value -> value
  where
    whitelistedHeaders =
      [ "Content-Type",
        "Accept-Encoding",
        "Content-Length",
        "Foo",
        "Baz"
      ]

-- | This is a complete test case that makes use of <https://httpbin.org> to
-- get various response status codes.
checkStatusCode :: Int -> SpecWith ()
checkStatusCode code =
  describe ("receiving status code " ++ show code) $
    it "works" $ do
      r <-
        prepareForShit $
          req
            GET
            (httpbin /: "status" /~ code)
            NoReqBody
            ignoreResponse
            mempty
      responseStatusCode r `shouldBe` code

-- | Exception selector that selects only 404 “Not found” exceptions.
selector404 :: HttpException -> Bool
selector404
  ( VanillaHttpException
      ( L.HttpExceptionRequest
          _
          (L.StatusCodeException response chunk)
        )
    ) =
    L.responseStatus response == Y.status404 && not (B.null chunk)
selector404 _ = False

-- | Same as 'selector404' except that it uses 'isStatusCodeException'.
selector404ByStatusCodeException :: HttpException -> Bool
selector404ByStatusCodeException e =
  case isStatusCodeException e of
    Nothing -> False
    Just r -> responseStatusCode r == 404

-- | The empty JSON 'Object'.
emptyObject :: Value
emptyObject = Object Aeson.KeyMap.empty

-- | Get a rendered JSON value as 'Text'.
reflectJSON :: (ToJSON a) => a -> Text
reflectJSON = T.decodeUtf8 . BL.toStrict . A.encode

-- | Clarify to the type checker that the inner computation is in the 'IO'
-- monad.
asIO :: IO a -> IO a
asIO = id