#include <cstdint>
#include <memory>
#include <string>
#include <utility>
#include <vector>

#include "absl/strings/str_join.h"
#include "quiche/http2/adapter/http2_protocol.h"
#include "quiche/http2/adapter/http2_visitor_interface.h"
#include "quiche/http2/adapter/mock_http2_visitor.h"
#include "quiche/http2/adapter/oghttp2_adapter.h"
#include "quiche/http2/adapter/oghttp2_util.h"
#include "quiche/http2/adapter/test_frame_sequence.h"
#include "quiche/http2/adapter/test_utils.h"
#include "quiche/common/platform/api/quiche_expect_bug.h"
#include "quiche/common/platform/api/quiche_test.h"
#include "quiche/spdy/core/http2_header_block.h"

namespace http2 {
namespace adapter {
namespace test {
namespace {

using ConnectionError = Http2VisitorInterface::ConnectionError;

using spdy::SpdyFrameType;
using testing::_;

enum FrameType {
  DATA,
  HEADERS,
  PRIORITY,
  RST_STREAM,
  SETTINGS,
  PUSH_PROMISE,
  PING,
  GOAWAY,
  WINDOW_UPDATE,
  CONTINUATION,
};

TEST(OgHttp2AdapterTest, ClientHandlesMetadata) {
  TestVisitor visitor;
  OgHttp2Adapter::Options options;
  options.perspective = Perspective::kClient;
  auto adapter = OgHttp2Adapter::Create(visitor, options);

  testing::InSequence s;

  const std::vector<Header> headers1 =
      ToHeaders({{":method", "GET"},
                 {":scheme", "http"},
                 {":authority", "example.com"},
                 {":path", "/this/is/request/one"}});

  const char* kSentinel1 = "arbitrary pointer 1";
  const int32_t stream_id1 = adapter->SubmitRequest(
      headers1, nullptr, true, const_cast<char*>(kSentinel1));
  ASSERT_GT(stream_id1, 0);
  QUICHE_LOG(INFO) << "Created stream: " << stream_id1;

  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(HEADERS, stream_id1, _,
                                         END_STREAM_FLAG | END_HEADERS_FLAG));
  EXPECT_CALL(visitor, OnFrameSent(HEADERS, stream_id1, _,
                                   END_STREAM_FLAG | END_HEADERS_FLAG, 0));

  int result = adapter->Send();
  EXPECT_EQ(0, result);
  absl::string_view data = visitor.data();
  EXPECT_THAT(data, testing::StartsWith(spdy::kHttp2ConnectionHeaderPrefix));
  data.remove_prefix(strlen(spdy::kHttp2ConnectionHeaderPrefix));
  EXPECT_THAT(data,
              EqualsFrames({SpdyFrameType::SETTINGS, SpdyFrameType::HEADERS}));
  visitor.Clear();

  const std::string stream_frames =
      TestFrameSequence()
          .ServerPreface()
          .Metadata(0, "Example connection metadata")
          .Headers(1,
                   {{":status", "200"},
                    {"server", "my-fake-server"},
                    {"date", "Tue, 6 Apr 2021 12:54:01 GMT"}},
                   /*fin=*/false)
          .Metadata(1, "Example stream metadata")
          .Data(1, "This is the response body.", true)
          .Serialize();

  // Server preface (empty SETTINGS)
  EXPECT_CALL(visitor, OnFrameHeader(0, 0, SETTINGS, 0));
  EXPECT_CALL(visitor, OnSettingsStart());
  EXPECT_CALL(visitor, OnSettingsEnd());

  EXPECT_CALL(visitor, OnFrameHeader(0, _, kMetadataFrameType, 4));
  EXPECT_CALL(visitor, OnBeginMetadataForStream(0, _));
  EXPECT_CALL(visitor, OnMetadataForStream(0, _));
  EXPECT_CALL(visitor, OnMetadataEndForStream(0));
  EXPECT_CALL(visitor, OnFrameHeader(1, _, HEADERS, 4));
  EXPECT_CALL(visitor, OnBeginHeadersForStream(1));
  EXPECT_CALL(visitor, OnHeaderForStream(1, ":status", "200"));
  EXPECT_CALL(visitor, OnHeaderForStream(1, "server", "my-fake-server"));
  EXPECT_CALL(visitor,
              OnHeaderForStream(1, "date", "Tue, 6 Apr 2021 12:54:01 GMT"));
  EXPECT_CALL(visitor, OnEndHeadersForStream(1));
  EXPECT_CALL(visitor, OnFrameHeader(1, _, kMetadataFrameType, 4));
  EXPECT_CALL(visitor, OnBeginMetadataForStream(1, _));
  EXPECT_CALL(visitor, OnMetadataForStream(1, _));
  EXPECT_CALL(visitor, OnMetadataEndForStream(1));
  EXPECT_CALL(visitor, OnFrameHeader(1, 26, DATA, 1));
  EXPECT_CALL(visitor, OnBeginDataForStream(1, 26));
  EXPECT_CALL(visitor, OnDataForStream(1, "This is the response body."));
  EXPECT_CALL(visitor, OnEndStream(1));
  EXPECT_CALL(visitor, OnCloseStream(1, Http2ErrorCode::HTTP2_NO_ERROR));

  const int64_t stream_result = adapter->ProcessBytes(stream_frames);
  EXPECT_EQ(stream_frames.size(), static_cast<size_t>(stream_result));

  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, ACK_FLAG));
  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, ACK_FLAG, 0));

  EXPECT_TRUE(adapter->want_write());
  result = adapter->Send();
  EXPECT_EQ(0, result);
  EXPECT_THAT(visitor.data(), EqualsFrames({SpdyFrameType::SETTINGS}));
}

TEST(OgHttp2AdapterTest, ClientHandlesMetadataWithEmptyPayload) {
  TestVisitor visitor;
  OgHttp2Adapter::Options options;
  options.perspective = Perspective::kClient;
  auto adapter = OgHttp2Adapter::Create(visitor, options);

  testing::InSequence s;

  const std::vector<Header> headers1 =
      ToHeaders({{":method", "GET"},
                 {":scheme", "http"},
                 {":authority", "example.com"},
                 {":path", "/this/is/request/one"}});

  const int32_t stream_id =
      adapter->SubmitRequest(headers1, nullptr, true, nullptr);
  ASSERT_GT(stream_id, 0);

  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(HEADERS, stream_id, _,
                                         END_STREAM_FLAG | END_HEADERS_FLAG));
  EXPECT_CALL(visitor, OnFrameSent(HEADERS, stream_id, _,
                                   END_STREAM_FLAG | END_HEADERS_FLAG, 0));

  int result = adapter->Send();
  EXPECT_EQ(0, result);
  absl::string_view data = visitor.data();
  EXPECT_THAT(data, testing::StartsWith(spdy::kHttp2ConnectionHeaderPrefix));
  data.remove_prefix(strlen(spdy::kHttp2ConnectionHeaderPrefix));
  EXPECT_THAT(data,
              EqualsFrames({SpdyFrameType::SETTINGS, SpdyFrameType::HEADERS}));
  visitor.Clear();

  const std::string stream_frames =
      TestFrameSequence()
          .ServerPreface()
          .Headers(1,
                   {{":status", "200"},
                    {"server", "my-fake-server"},
                    {"date", "Tue, 6 Apr 2021 12:54:01 GMT"}},
                   /*fin=*/false)
          .Metadata(1, "")
          .Data(1, "This is the response body.", true)
          .Serialize();

  // Server preface (empty SETTINGS)
  EXPECT_CALL(visitor, OnFrameHeader(0, 0, SETTINGS, 0));
  EXPECT_CALL(visitor, OnSettingsStart());
  EXPECT_CALL(visitor, OnSettingsEnd());

  EXPECT_CALL(visitor, OnFrameHeader(1, _, HEADERS, 4));
  EXPECT_CALL(visitor, OnBeginHeadersForStream(1));
  EXPECT_CALL(visitor, OnHeaderForStream(1, _, _)).Times(3);
  EXPECT_CALL(visitor, OnEndHeadersForStream(1));
  EXPECT_CALL(visitor, OnFrameHeader(1, _, kMetadataFrameType, 4));
  EXPECT_CALL(visitor, OnBeginMetadataForStream(1, _));
  EXPECT_CALL(visitor, OnMetadataEndForStream(1));
  EXPECT_CALL(visitor, OnFrameHeader(1, _, DATA, 1));
  EXPECT_CALL(visitor, OnBeginDataForStream(1, _));
  EXPECT_CALL(visitor, OnDataForStream(1, "This is the response body."));
  EXPECT_CALL(visitor, OnEndStream(1));
  EXPECT_CALL(visitor, OnCloseStream(1, Http2ErrorCode::HTTP2_NO_ERROR));

  const int64_t stream_result = adapter->ProcessBytes(stream_frames);
  EXPECT_EQ(stream_frames.size(), static_cast<size_t>(stream_result));
}

TEST(OgHttp2AdapterTest, ClientHandlesMetadataWithPayloadError) {
  TestVisitor visitor;
  OgHttp2Adapter::Options options;
  options.perspective = Perspective::kClient;
  auto adapter = OgHttp2Adapter::Create(visitor, options);

  testing::InSequence s;

  const std::vector<Header> headers =
      ToHeaders({{":method", "GET"},
                 {":scheme", "http"},
                 {":authority", "example.com"},
                 {":path", "/this/is/request/one"}});

  const int32_t stream_id =
      adapter->SubmitRequest(headers, nullptr, true, nullptr);
  ASSERT_GT(stream_id, 0);

  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(HEADERS, stream_id, _,
                                         END_STREAM_FLAG | END_HEADERS_FLAG));
  EXPECT_CALL(visitor, OnFrameSent(HEADERS, stream_id, _,
                                   END_STREAM_FLAG | END_HEADERS_FLAG, 0));

  int result = adapter->Send();
  EXPECT_EQ(0, result);
  visitor.Clear();

  const std::string stream_frames =
      TestFrameSequence()
          .ServerPreface()
          .Metadata(0, "Example connection metadata")
          .Headers(stream_id,
                   {{":status", "200"},
                    {"server", "my-fake-server"},
                    {"date", "Tue, 6 Apr 2021 12:54:01 GMT"}},
                   /*fin=*/false)
          .Metadata(stream_id, "Example stream metadata")
          .Data(stream_id, "This is the response body.", true)
          .Serialize();

  // Server preface (empty SETTINGS)
  EXPECT_CALL(visitor, OnFrameHeader(0, 0, SETTINGS, 0));
  EXPECT_CALL(visitor, OnSettingsStart());
  EXPECT_CALL(visitor, OnSettingsEnd());

  EXPECT_CALL(visitor, OnFrameHeader(0, _, kMetadataFrameType, 4));
  EXPECT_CALL(visitor, OnBeginMetadataForStream(0, _));
  EXPECT_CALL(visitor, OnMetadataForStream(0, _));
  EXPECT_CALL(visitor, OnMetadataEndForStream(0));
  EXPECT_CALL(visitor, OnFrameHeader(stream_id, _, HEADERS, 4));
  EXPECT_CALL(visitor, OnBeginHeadersForStream(stream_id));
  EXPECT_CALL(visitor, OnHeaderForStream(stream_id, _, _)).Times(3);
  EXPECT_CALL(visitor, OnEndHeadersForStream(stream_id));
  EXPECT_CALL(visitor, OnFrameHeader(stream_id, _, kMetadataFrameType, 4));
  EXPECT_CALL(visitor, OnBeginMetadataForStream(stream_id, _));
  EXPECT_CALL(visitor, OnMetadataForStream(stream_id, _))
      .WillOnce(testing::Return(false));
  // Remaining frames are not processed due to the error.
  EXPECT_CALL(visitor, OnConnectionError(ConnectionError::kParseError));

  const int64_t stream_result = adapter->ProcessBytes(stream_frames);
  // Negative integer returned to indicate an error.
  EXPECT_LT(stream_result, 0);

  EXPECT_CALL(visitor, OnBeforeFrameSent(GOAWAY, 0, _, 0x0));
  EXPECT_CALL(visitor,
              OnFrameSent(GOAWAY, 0, _, 0x0,
                          static_cast<int>(Http2ErrorCode::INTERNAL_ERROR)));

  EXPECT_FALSE(adapter->want_read());
  EXPECT_TRUE(adapter->want_write());
  result = adapter->Send();
  EXPECT_EQ(0, result);
  EXPECT_THAT(visitor.data(), EqualsFrames({SpdyFrameType::GOAWAY}));
}

TEST(OgHttp2AdapterTest, ClientHandlesMetadataWithCompletionError) {
  TestVisitor visitor;
  OgHttp2Adapter::Options options;
  options.perspective = Perspective::kClient;
  auto adapter = OgHttp2Adapter::Create(visitor, options);

  testing::InSequence s;

  const std::vector<Header> headers =
      ToHeaders({{":method", "GET"},
                 {":scheme", "http"},
                 {":authority", "example.com"},
                 {":path", "/this/is/request/one"}});

  const int32_t stream_id =
      adapter->SubmitRequest(headers, nullptr, true, nullptr);
  ASSERT_GT(stream_id, 0);

  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(HEADERS, stream_id, _,
                                         END_STREAM_FLAG | END_HEADERS_FLAG));
  EXPECT_CALL(visitor, OnFrameSent(HEADERS, stream_id, _,
                                   END_STREAM_FLAG | END_HEADERS_FLAG, 0));

  int result = adapter->Send();
  EXPECT_EQ(0, result);
  visitor.Clear();

  const std::string stream_frames =
      TestFrameSequence()
          .ServerPreface()
          .Metadata(0, "Example connection metadata")
          .Headers(stream_id,
                   {{":status", "200"},
                    {"server", "my-fake-server"},
                    {"date", "Tue, 6 Apr 2021 12:54:01 GMT"}},
                   /*fin=*/false)
          .Metadata(stream_id, "Example stream metadata")
          .Data(stream_id, "This is the response body.", true)
          .Serialize();

  // Server preface (empty SETTINGS)
  EXPECT_CALL(visitor, OnFrameHeader(0, 0, SETTINGS, 0));
  EXPECT_CALL(visitor, OnSettingsStart());
  EXPECT_CALL(visitor, OnSettingsEnd());

  EXPECT_CALL(visitor, OnFrameHeader(0, _, kMetadataFrameType, 4));
  EXPECT_CALL(visitor, OnBeginMetadataForStream(0, _));
  EXPECT_CALL(visitor, OnMetadataForStream(0, _));
  EXPECT_CALL(visitor, OnMetadataEndForStream(0));
  EXPECT_CALL(visitor, OnFrameHeader(stream_id, _, HEADERS, 4));
  EXPECT_CALL(visitor, OnBeginHeadersForStream(stream_id));
  EXPECT_CALL(visitor, OnHeaderForStream(stream_id, _, _)).Times(3);
  EXPECT_CALL(visitor, OnEndHeadersForStream(stream_id));
  EXPECT_CALL(visitor, OnFrameHeader(stream_id, _, kMetadataFrameType, 4));
  EXPECT_CALL(visitor, OnBeginMetadataForStream(stream_id, _));
  EXPECT_CALL(visitor, OnMetadataForStream(stream_id, _));
  EXPECT_CALL(visitor, OnMetadataEndForStream(stream_id))
      .WillOnce(testing::Return(false));
  // Remaining frames are not processed due to the error.
  EXPECT_CALL(visitor, OnConnectionError(ConnectionError::kParseError));

  const int64_t stream_result = adapter->ProcessBytes(stream_frames);
  // Negative integer returned to indicate an error.
  EXPECT_LT(stream_result, 0);

  EXPECT_CALL(visitor, OnBeforeFrameSent(GOAWAY, 0, _, 0x0));
  EXPECT_CALL(visitor,
              OnFrameSent(GOAWAY, 0, _, 0x0,
                          static_cast<int>(Http2ErrorCode::INTERNAL_ERROR)));

  EXPECT_FALSE(adapter->want_read());
  EXPECT_TRUE(adapter->want_write());
  result = adapter->Send();
  EXPECT_EQ(0, result);
  EXPECT_THAT(visitor.data(), EqualsFrames({SpdyFrameType::GOAWAY}));
}

TEST(OgHttp2AdapterTest, ClientSendsMetadataAfterFlowControlBlock) {
  TestVisitor visitor;
  OgHttp2Adapter::Options options;
  options.perspective = Perspective::kClient;
  auto adapter = OgHttp2Adapter::Create(visitor, options);

  testing::InSequence s;

  const std::vector<Header> headers1 =
      ToHeaders({{":method", "GET"},
                 {":scheme", "http"},
                 {":authority", "example.com"},
                 {":path", "/this/is/request/one"}});

  const std::string kBody = std::string(100 * 1024, 'a');
  visitor.AppendPayloadForStream(1, kBody);
  visitor.SetEndData(1, false);
  auto body1 = std::make_unique<VisitorDataSource>(visitor, 1);

  const int32_t stream_id1 =
      adapter->SubmitRequest(headers1, std::move(body1), false, nullptr);
  ASSERT_EQ(stream_id1, 1);

  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(HEADERS, stream_id1, _, 0x4));
  EXPECT_CALL(visitor, OnFrameSent(HEADERS, stream_id1, _, 0x4, 0));
  // 4 DATA frames should saturate the default 64kB stream/connection flow
  // control window.
  EXPECT_CALL(visitor, OnFrameSent(DATA, stream_id1, _, 0x0, 0)).Times(4);

  int result = adapter->Send();
  EXPECT_EQ(0, result);
  EXPECT_FALSE(adapter->want_write());
  EXPECT_EQ(0, adapter->GetSendWindowSize());

  auto source = std::make_unique<TestMetadataSource>(ToHeaderBlock(ToHeaders(
      {{"query-cost", "is too darn high"}, {"secret-sauce", "hollandaise"}})));
  adapter->SubmitMetadata(1, 16384u, std::move(source));
  EXPECT_CALL(visitor, OnBeforeFrameSent(kMetadataFrameType, 1, _, 0x4));
  EXPECT_CALL(visitor, OnFrameSent(kMetadataFrameType, 1, _, 0x4, 0));

  result = adapter->Send();
  EXPECT_EQ(0, result);
}

TEST(OgHttp2AdapterTest, ClientSendsMetadataWithContinuation) {
  TestVisitor visitor;
  OgHttp2Adapter::Options options;
  options.perspective = Perspective::kServer;
  auto adapter = OgHttp2Adapter::Create(visitor, options);
  EXPECT_FALSE(adapter->want_write());

  const std::string frames =
      TestFrameSequence()
          .ClientPreface()
          .Metadata(0, "Example connection metadata in multiple frames", true)
          .Headers(1,
                   {{":method", "GET"},
                    {":scheme", "https"},
                    {":authority", "example.com"},
                    {":path", "/this/is/request/one"}},
                   /*fin=*/false,
                   /*add_continuation=*/true)
          .Metadata(1,
                    "Some stream metadata that's also sent in multiple frames",
                    true)
          .Serialize();
  testing::InSequence s;

  // Client preface (empty SETTINGS)
  EXPECT_CALL(visitor, OnFrameHeader(0, 0, SETTINGS, 0));
  EXPECT_CALL(visitor, OnSettingsStart());
  EXPECT_CALL(visitor, OnSettingsEnd());
  // Metadata on stream 0
  EXPECT_CALL(visitor, OnFrameHeader(0, _, kMetadataFrameType, 0));
  EXPECT_CALL(visitor, OnBeginMetadataForStream(0, _));
  EXPECT_CALL(visitor, OnMetadataForStream(0, _));
  EXPECT_CALL(visitor, OnFrameHeader(0, _, kMetadataFrameType, 4));
  EXPECT_CALL(visitor, OnBeginMetadataForStream(0, _));
  EXPECT_CALL(visitor, OnMetadataForStream(0, _));
  EXPECT_CALL(visitor, OnMetadataEndForStream(0));

  // Stream 1
  EXPECT_CALL(visitor, OnFrameHeader(1, _, HEADERS, 0));
  EXPECT_CALL(visitor, OnBeginHeadersForStream(1));
  EXPECT_CALL(visitor, OnHeaderForStream(1, ":method", "GET"));
  EXPECT_CALL(visitor, OnHeaderForStream(1, ":scheme", "https"));
  EXPECT_CALL(visitor, OnFrameHeader(1, _, CONTINUATION, 4));
  EXPECT_CALL(visitor, OnHeaderForStream(1, ":authority", "example.com"));
  EXPECT_CALL(visitor, OnHeaderForStream(1, ":path", "/this/is/request/one"));
  EXPECT_CALL(visitor, OnEndHeadersForStream(1));
  // Metadata on stream 1
  EXPECT_CALL(visitor, OnFrameHeader(1, _, kMetadataFrameType, 0));
  EXPECT_CALL(visitor, OnBeginMetadataForStream(1, _));
  EXPECT_CALL(visitor, OnMetadataForStream(1, _));
  EXPECT_CALL(visitor, OnFrameHeader(1, _, kMetadataFrameType, 4));
  EXPECT_CALL(visitor, OnBeginMetadataForStream(1, _));
  EXPECT_CALL(visitor, OnMetadataForStream(1, _));
  EXPECT_CALL(visitor, OnMetadataEndForStream(1));

  const int64_t result = adapter->ProcessBytes(frames);
  EXPECT_EQ(frames.size(), static_cast<size_t>(result));
  EXPECT_EQ("Example connection metadata in multiple frames",
            absl::StrJoin(visitor.GetMetadata(0), ""));
  EXPECT_EQ("Some stream metadata that's also sent in multiple frames",
            absl::StrJoin(visitor.GetMetadata(1), ""));
}

TEST(OgHttp2AdapterTest, SubmitMetadata) {
  TestVisitor visitor;
  OgHttp2Adapter::Options options;
  options.perspective = Perspective::kServer;
  auto adapter = OgHttp2Adapter::Create(visitor, options);

  auto source = std::make_unique<TestMetadataSource>(ToHeaderBlock(ToHeaders(
      {{"query-cost", "is too darn high"}, {"secret-sauce", "hollandaise"}})));
  adapter->SubmitMetadata(1, 16384u, std::move(source));
  EXPECT_TRUE(adapter->want_write());

  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(kMetadataFrameType, 1, _, 0x4));
  EXPECT_CALL(visitor, OnFrameSent(kMetadataFrameType, 1, _, 0x4, 0));

  int result = adapter->Send();
  EXPECT_EQ(0, result);
  EXPECT_THAT(visitor.data(),
              EqualsFrames({SpdyFrameType::SETTINGS,
                            static_cast<SpdyFrameType>(kMetadataFrameType)}));
  EXPECT_FALSE(adapter->want_write());
}

TEST(OgHttp2AdapterTest, SubmitMetadataMultipleFrames) {
  TestVisitor visitor;
  OgHttp2Adapter::Options options;
  options.perspective = Perspective::kServer;
  auto adapter = OgHttp2Adapter::Create(visitor, options);

  const auto kLargeValue = std::string(63 * 1024, 'a');
  auto source = std::make_unique<TestMetadataSource>(
      ToHeaderBlock(ToHeaders({{"large-value", kLargeValue}})));
  adapter->SubmitMetadata(1, 16384u, std::move(source));
  EXPECT_TRUE(adapter->want_write());

  testing::InSequence seq;
  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(kMetadataFrameType, 1, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(kMetadataFrameType, 1, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(kMetadataFrameType, 1, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(kMetadataFrameType, 1, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(kMetadataFrameType, 1, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(kMetadataFrameType, 1, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(kMetadataFrameType, 1, _, 0x4));
  EXPECT_CALL(visitor, OnFrameSent(kMetadataFrameType, 1, _, 0x4, 0));

  int result = adapter->Send();
  EXPECT_EQ(0, result);
  absl::string_view serialized = visitor.data();
  EXPECT_THAT(serialized,
              EqualsFrames({SpdyFrameType::SETTINGS,
                            static_cast<SpdyFrameType>(kMetadataFrameType),
                            static_cast<SpdyFrameType>(kMetadataFrameType),
                            static_cast<SpdyFrameType>(kMetadataFrameType),
                            static_cast<SpdyFrameType>(kMetadataFrameType)}));
  EXPECT_FALSE(adapter->want_write());
}

TEST(OgHttp2AdapterTest, SubmitConnectionMetadata) {
  TestVisitor visitor;
  OgHttp2Adapter::Options options;
  options.perspective = Perspective::kServer;
  auto adapter = OgHttp2Adapter::Create(visitor, options);

  auto source = std::make_unique<TestMetadataSource>(ToHeaderBlock(ToHeaders(
      {{"query-cost", "is too darn high"}, {"secret-sauce", "hollandaise"}})));
  adapter->SubmitMetadata(0, 16384u, std::move(source));
  EXPECT_TRUE(adapter->want_write());

  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(kMetadataFrameType, 0, _, 0x4));
  EXPECT_CALL(visitor, OnFrameSent(kMetadataFrameType, 0, _, 0x4, 0));

  int result = adapter->Send();
  EXPECT_EQ(0, result);
  EXPECT_THAT(visitor.data(),
              EqualsFrames({SpdyFrameType::SETTINGS,
                            static_cast<SpdyFrameType>(kMetadataFrameType)}));
  EXPECT_FALSE(adapter->want_write());
}

TEST(OgHttp2AdapterTest, ServerQueuesMetadataThenTrailers) {
  TestVisitor visitor;
  OgHttp2Adapter::Options options;
  options.perspective = Perspective::kServer;
  auto adapter = OgHttp2Adapter::Create(visitor, options);
  EXPECT_FALSE(adapter->want_write());

  const std::string frames = TestFrameSequence()
                                 .ClientPreface()
                                 .Headers(1,
                                          {{":method", "GET"},
                                           {":scheme", "https"},
                                           {":authority", "example.com"},
                                           {":path", "/"}},
                                          /*fin=*/true)
                                 .Serialize();
  testing::InSequence s;

  // Client preface (empty SETTINGS)
  EXPECT_CALL(visitor, OnFrameHeader(0, 0, SETTINGS, 0));
  EXPECT_CALL(visitor, OnSettingsStart());
  EXPECT_CALL(visitor, OnSettingsEnd());
  // Stream 1
  EXPECT_CALL(visitor, OnFrameHeader(1, _, HEADERS, 5));
  EXPECT_CALL(visitor, OnBeginHeadersForStream(1));
  EXPECT_CALL(visitor, OnHeaderForStream(1, _, _)).Times(4);
  EXPECT_CALL(visitor, OnEndHeadersForStream(1));
  EXPECT_CALL(visitor, OnEndStream(1));

  const int64_t result = adapter->ProcessBytes(frames);
  EXPECT_EQ(frames.size(), static_cast<size_t>(result));

  const absl::string_view kBody = "This is an example response body.";

  // The body source must indicate that the end of the body is not the end of
  // the stream.
  visitor.AppendPayloadForStream(1, kBody);
  visitor.SetEndData(1, false);
  auto body1 = std::make_unique<VisitorDataSource>(visitor, 1);
  int submit_result = adapter->SubmitResponse(
      1, ToHeaders({{":status", "200"}, {"x-comment", "Sure, sounds good."}}),
      std::move(body1), false);
  EXPECT_EQ(submit_result, 0);
  EXPECT_TRUE(adapter->want_write());

  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, 0x0));
  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, 0x0, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(SETTINGS, 0, _, ACK_FLAG));
  EXPECT_CALL(visitor, OnFrameSent(SETTINGS, 0, _, ACK_FLAG, 0));
  EXPECT_CALL(visitor, OnBeforeFrameSent(HEADERS, 1, _, 0x4));
  EXPECT_CALL(visitor, OnFrameSent(HEADERS, 1, _, 0x4, 0));
  EXPECT_CALL(visitor, OnFrameSent(DATA, 1, _, 0x0, 0));

  int send_result = adapter->Send();
  EXPECT_EQ(0, send_result);
  EXPECT_THAT(visitor.data(),
              EqualsFrames({SpdyFrameType::SETTINGS, SpdyFrameType::SETTINGS,
                            SpdyFrameType::HEADERS, SpdyFrameType::DATA}));
  EXPECT_THAT(visitor.data(), testing::HasSubstr(kBody));
  visitor.Clear();
  EXPECT_FALSE(adapter->want_write());

  spdy::Http2HeaderBlock block;
  block["key"] = "wild value!";
  adapter->SubmitMetadata(
      1, 16384u, std::make_unique<TestMetadataSource>(std::move(block)));

  int trailer_result =
      adapter->SubmitTrailer(1, ToHeaders({{":final-status", "a-ok"}}));
  ASSERT_EQ(trailer_result, 0);
  EXPECT_TRUE(adapter->want_write());

  EXPECT_CALL(visitor, OnBeforeFrameSent(kMetadataFrameType, 1, _, 0x4));
  EXPECT_CALL(visitor, OnFrameSent(kMetadataFrameType, 1, _, 0x4, 0));

  EXPECT_CALL(visitor, OnBeforeFrameSent(HEADERS, 1, _,
                                         END_STREAM_FLAG | END_HEADERS_FLAG));
  EXPECT_CALL(visitor, OnFrameSent(HEADERS, 1, _,
                                   END_STREAM_FLAG | END_HEADERS_FLAG, 0));

  EXPECT_CALL(visitor, OnCloseStream(1, Http2ErrorCode::HTTP2_NO_ERROR));

  send_result = adapter->Send();
  EXPECT_EQ(0, send_result);
  EXPECT_THAT(visitor.data(),
              EqualsFrames({static_cast<SpdyFrameType>(kMetadataFrameType),
                            SpdyFrameType::HEADERS}));
}

}  // namespace
}  // namespace test
}  // namespace adapter
}  // namespace http2