{-# LANGUAGE DuplicateRecordFields #-}
{-# LANGUAGE OverloadedStrings #-}

import Data.Bytes (Bytes)
import Data.Bytes.Chunks (Chunks (ChunksCons, ChunksNil))
import Http.Request (Request (Request), RequestLine (RequestLine))
import Http.Types (Bodied (Bodied), Header (Header), Response)
import OkChannel (M (M))
import Test.Tasty (TestTree, defaultMain, testGroup)
import Test.Tasty.HUnit (testCase, (@=?))

import Data.Bytes qualified as Bytes
import Data.Bytes.Chunks qualified as Chunks
import Data.Bytes.Text.Ascii qualified as Ascii
import GHC.Exts qualified as Exts
import Http.Bodied qualified
import Http.Header qualified
import Http.Headers qualified as Headers
import Http.Request qualified as Request
import OkExchange qualified as E

main :: IO ()
main = defaultMain tests

tests :: TestTree
tests =
  testGroup
    "tests"
    [ testCase "get-a" $ do
        (input, output, Bodied {body}) <- evaluateM (E.exchange () getReqA) (Chunks.fromBytes getRespA)
        body @=? ChunksNil
        input @=? mempty
        output @=? Chunks.concat (Request.bodiedToChunks getReqA)
    , testCase "get-chunked-a" $ do
        (input, output, Bodied {body}) <- evaluateM (E.exchange () getReqA) (Chunks.fromBytes getRespChunkedA)
        body @=? ChunksNil
        input @=? mempty
        output @=? Chunks.concat (Request.bodiedToChunks getReqA)
    , testCase "get-chunked-byte-by-byte-a" $ do
        (input, output, Bodied {body}) <- evaluateM (E.exchange () getReqA) (bytesToSingleByteChunks getRespChunkedA)
        body @=? ChunksNil
        input @=? mempty
        output @=? Chunks.concat (Request.bodiedToChunks getReqA)
    , testCase "get-body-a" $ do
        (input, output, Bodied {body}) <- evaluateM (E.exchange () getReqA) (Chunks.fromBytes getRespBodyA)
        input @=? mempty
        body @=? ChunksCons (Ascii.fromString "helloworld") ChunksNil
        output @=? Chunks.concat (Request.bodiedToChunks getReqA)
    , testCase "get-chunked-b" $ do
        (input, output, Bodied {body}) <- evaluateM (E.exchange () getReqA) (Chunks.fromBytes getRespChunkedB)
        Ascii.fromString "hello to my friends." @=? Chunks.concat body
        mempty @=? input
        Chunks.concat (Request.bodiedToChunks getReqA) @=? output
    , testCase "get-chunked-byte-by-byte-b" $ do
        (input, output, Bodied {body}) <- evaluateM (E.exchange () getReqA) (bytesToSingleByteChunks getRespChunkedB)
        Ascii.fromString "hello to my friends." @=? Chunks.concat body
        mempty @=? input
        Chunks.concat (Request.bodiedToChunks getReqA) @=? output
    , testCase "get-chunked-two-by-two-b" $ do
        (input, output, Bodied {body}) <- evaluateM (E.exchange () getReqA) (bytesToDoubletonByteChunks getRespChunkedB)
        Ascii.fromString "hello to my friends." @=? Chunks.concat body
        mempty @=? input
        Chunks.concat (Request.bodiedToChunks getReqA) @=? output
    ]

bytesToSingleByteChunks :: Bytes -> Chunks
bytesToSingleByteChunks =
  Bytes.foldr'
    ( \w acc -> ChunksCons (Bytes.singleton w) acc
    )
    ChunksNil

bytesToDoubletonByteChunks :: Bytes -> Chunks
bytesToDoubletonByteChunks b0 = go (Exts.toList b0)
 where
  go (x : y : zs) = ChunksCons (Exts.fromList [x, y]) (go zs)
  go [x] = ChunksCons (Bytes.singleton x) ChunksNil
  go [] = ChunksNil

evaluateM ::
  M (Either E.Exception (Bodied Response)) ->
  Chunks -> -- prebuilt response
  IO (Chunks, Bytes, Bodied Response)
evaluateM (M f) resp = case f resp mempty of
  (input, output, r) -> case r of
    Left e -> case e of
      E.Http err -> fail ("exchange http protocol failure: " ++ show err)
      E.Receive err -> fail ("exchange http transport receive failure: " ++ show err)
    Right b -> pure (input, output, b)

getReqA :: Bodied Request
getReqA =
  Bodied
    { metadata =
        Request
          { requestLine =
              RequestLine
                { method = "GET"
                , path = "/health"
                }
          , headers =
              Headers.fromArray $
                Exts.fromList
                  [ Header {name = "Host", value = "example.com"}
                  ]
          }
    , body = mempty
    }

getRespA :: Bytes
getRespA =
  Ascii.fromString
    "HTTP/1.1 200 OK\r\n\
    \Server: testsuite/1.2.3\r\n\
    \Content-Type: text/plain\r\n\r\n"

getRespBodyA :: Bytes
getRespBodyA =
  Ascii.fromString
    "HTTP/1.1 200 OK\r\n\
    \Server: testsuite/1.2.3\r\n\
    \Content-Type: text/plain\r\n\
    \Content-Length: 10\r\n\r\n\
    \helloworld"

getRespChunkedA :: Bytes
getRespChunkedA =
  Ascii.fromString
    "HTTP/1.1 200 OK\r\n\
    \Server: testsuite/1.2.3\r\n\
    \Transfer-Encoding: chunked\r\n\
    \Content-Type: text/plain\r\n\r\n\
    \0\r\n\r\n"

getRespChunkedB :: Bytes
getRespChunkedB =
  Ascii.fromString
    "HTTP/1.1 200 OK\r\n\
    \Server: testsuite/1.2.3\r\n\
    \Transfer-Encoding: chunked\r\n\
    \Content-Type: text/plain\r\n\r\n\
    \5\r\nhello\r\n\
    \f\r\n to my friends.\r\n\
    \0\r\n\r\n"