/*
 * Copyright (C) 2019 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "src/perfetto_cmd/packet_writer.h"

#include <string.h>

#include <random>

#include "perfetto/base/build_config.h"
#include "perfetto/ext/base/file_utils.h"
#include "perfetto/ext/base/scoped_file.h"
#include "perfetto/ext/base/temp_file.h"
#include "perfetto/ext/tracing/core/trace_packet.h"
#include "src/perfetto_cmd/packet_writer.h"
#include "test/gtest_and_gmock.h"

#include "protos/perfetto/trace/test_event.gen.h"
#include "protos/perfetto/trace/trace.gen.h"
#include "protos/perfetto/trace/trace_packet.gen.h"

#if PERFETTO_BUILDFLAG(PERFETTO_ZLIB)
#include <zlib.h>
#endif

namespace perfetto {
namespace {

using TracePacketProto = protos::gen::TracePacket;

template <typename F>
TracePacket CreateTracePacket(F fill_function) {
  TracePacketProto msg;
  fill_function(&msg);
  std::vector<uint8_t> buf = msg.SerializeAsArray();
  Slice slice = Slice::Allocate(buf.size());
  memcpy(slice.own_data(), buf.data(), buf.size());
  perfetto::TracePacket packet;
  packet.AddSlice(std::move(slice));
  return packet;
}

#if PERFETTO_BUILDFLAG(PERFETTO_ZLIB)
std::string RandomString(size_t size) {
  std::minstd_rand0 rnd(0);
  std::uniform_int_distribution<> dist(0, 255);
  std::string s;
  s.resize(size);
  for (size_t i = 0; i < s.size(); i++)
    s[i] = static_cast<char>(dist(rnd));
  return s;
}

std::string Decompress(const std::string& data) {
  uint8_t out[1024];

  z_stream stream{};
  stream.next_in = reinterpret_cast<uint8_t*>(const_cast<char*>(data.data()));
  stream.avail_in = static_cast<unsigned int>(data.size());

  EXPECT_EQ(inflateInit(&stream), Z_OK);
  std::string s;

  int ret;
  do {
    stream.next_out = out;
    stream.avail_out = sizeof(out);
    ret = inflate(&stream, Z_NO_FLUSH);
    EXPECT_NE(ret, Z_STREAM_ERROR);
    EXPECT_NE(ret, Z_NEED_DICT);
    EXPECT_NE(ret, Z_DATA_ERROR);
    EXPECT_NE(ret, Z_MEM_ERROR);
    s.append(reinterpret_cast<char*>(out), sizeof(out) - stream.avail_out);
  } while (ret != Z_STREAM_END);

  inflateEnd(&stream);
  return s;
}
#endif  // PERFETTO_BUILDFLAG(PERFETTO_ZLIB)

TEST(PacketWriterTest, FilePacketWriter) {
  base::TempFile tmp = base::TempFile::CreateUnlinked();
  base::ScopedResource<FILE*, fclose, nullptr> f(
      fdopen(tmp.ReleaseFD().release(), "wb"));

  std::vector<perfetto::TracePacket> packets;
  packets.push_back(CreateTracePacket([](TracePacketProto* msg) {
    auto* for_testing = msg->mutable_for_testing();
    for_testing->set_str("abc");
  }));

  {
    std::unique_ptr<PacketWriter> writer = CreateFilePacketWriter(*f);
    EXPECT_TRUE(writer->WritePackets(std::move(packets)));
  }

  fseek(*f, 0, SEEK_SET);
  std::string s;
  EXPECT_TRUE(base::ReadFileStream(*f, &s));
  EXPECT_GT(s.size(), 0u);

  protos::gen::Trace trace;
  EXPECT_TRUE(trace.ParseFromString(s));
  EXPECT_EQ(trace.packet()[0].for_testing().str(), "abc");
}

#if PERFETTO_BUILDFLAG(PERFETTO_ZLIB)

TEST(PacketWriterTest, ZipPacketWriter) {
  base::TempFile tmp = base::TempFile::CreateUnlinked();
  base::ScopedResource<FILE*, fclose, nullptr> f(
      fdopen(tmp.ReleaseFD().release(), "wb"));

  std::vector<perfetto::TracePacket> packets;
  packets.push_back(CreateTracePacket([](TracePacketProto* msg) {
    auto* for_testing = msg->mutable_for_testing();
    for_testing->set_str("abc");
  }));

  {
    std::unique_ptr<PacketWriter> writer =
        CreateZipPacketWriter(CreateFilePacketWriter(*f));
    EXPECT_TRUE(writer->WritePackets(std::move(packets)));
  }

  std::string s;
  fseek(*f, 0, SEEK_SET);
  EXPECT_TRUE(base::ReadFileStream(*f, &s));
  EXPECT_GT(s.size(), 0u);

  protos::gen::Trace trace;
  EXPECT_TRUE(trace.ParseFromString(s));

  const std::string& data = trace.packet()[0].compressed_packets();
  EXPECT_GT(data.size(), 0u);

  protos::gen::Trace subtrace;
  EXPECT_TRUE(subtrace.ParseFromString(Decompress(data)));
  EXPECT_EQ(subtrace.packet()[0].for_testing().str(), "abc");
}

TEST(PacketWriterTest, ZipPacketWriter_Empty) {
  base::TempFile tmp = base::TempFile::CreateUnlinked();
  base::ScopedResource<FILE*, fclose, nullptr> f(
      fdopen(tmp.ReleaseFD().release(), "wb"));

  {
    std::unique_ptr<PacketWriter> writer =
        CreateZipPacketWriter(CreateFilePacketWriter(*f));
  }

  EXPECT_EQ(fseek(*f, 0, SEEK_END), 0);
}

TEST(PacketWriterTest, ZipPacketWriter_EmptyWithEmptyWrite) {
  base::TempFile tmp = base::TempFile::CreateUnlinked();
  base::ScopedResource<FILE*, fclose, nullptr> f(
      fdopen(tmp.ReleaseFD().release(), "wb"));

  {
    std::unique_ptr<PacketWriter> writer =
        CreateZipPacketWriter(CreateFilePacketWriter(*f));
    writer->WritePackets(std::vector<TracePacket>());
    writer->WritePackets(std::vector<TracePacket>());
    writer->WritePackets(std::vector<TracePacket>());
  }

  EXPECT_EQ(fseek(*f, 0, SEEK_END), 0);
}

TEST(PacketWriterTest, ZipPacketWriter_ShouldCompress) {
  base::TempFile tmp = base::TempFile::CreateUnlinked();
  base::ScopedResource<FILE*, fclose, nullptr> f(
      fdopen(tmp.ReleaseFD().release(), "wb"));
  size_t uncompressed_size = 0;

  std::vector<perfetto::TracePacket> packets;
  for (size_t i = 0; i < 200; i++) {
    packets.push_back(CreateTracePacket([](TracePacketProto* msg) {
      auto* for_testing = msg->mutable_for_testing();
      for_testing->set_str("abcdefghijklmn");
    }));

    packets.push_back(CreateTracePacket([](TracePacketProto* msg) {
      auto* for_testing = msg->mutable_for_testing();
      for_testing->set_str("abcdefghijklmn");
    }));

    for (const TracePacket& packet : packets)
      uncompressed_size += packet.size();
  }

  {
    std::unique_ptr<PacketWriter> writer =
        CreateZipPacketWriter(CreateFilePacketWriter(*f));
    EXPECT_TRUE(writer->WritePackets(std::move(packets)));
  }

  std::string s;
  EXPECT_LT(fseek(*f, 0, SEEK_END), static_cast<int>(uncompressed_size));
  fseek(*f, 0, SEEK_SET);
  EXPECT_TRUE(base::ReadFileStream(*f, &s));
  EXPECT_GT(s.size(), 0u);

  protos::gen::Trace trace;
  EXPECT_TRUE(trace.ParseFromString(s));

  size_t packet_count = 0;
  for (const auto& packet : trace.packet()) {
    const std::string& data = packet.compressed_packets();
    EXPECT_GT(data.size(), 0u);
    EXPECT_LT(data.size(), 500 * 1024u);
    protos::gen::Trace subtrace;
    EXPECT_TRUE(subtrace.ParseFromString(Decompress(data)));
    for (const auto& subpacket : subtrace.packet()) {
      packet_count++;
      EXPECT_EQ(subpacket.for_testing().str(), "abcdefghijklmn");
    }
  }

  EXPECT_EQ(packet_count, 200 * 2u);
}

TEST(PacketWriterTest, ZipPacketWriter_LargePacket) {
  base::TempFile tmp = base::TempFile::CreateUnlinked();
  base::ScopedResource<FILE*, fclose, nullptr> f(
      fdopen(tmp.ReleaseFD().release(), "wb"));

  std::vector<perfetto::TracePacket> packets;

  auto add_packet = [&packets](size_t size) {
    std::string s = RandomString(size);
    packets.push_back(CreateTracePacket([&s](TracePacketProto* msg) {
      auto* for_testing = msg->mutable_for_testing();
      for_testing->set_str(s);
    }));
  };

  add_packet(1 * 1024 * 1024);
  add_packet(10);
  add_packet(1 * 1024 * 1024);
  add_packet(1 * 1024);
  add_packet(1 * 1024);
  add_packet(2 * 1024 * 1024);

  {
    std::unique_ptr<PacketWriter> writer =
        CreateZipPacketWriter(CreateFilePacketWriter(*f));
    EXPECT_TRUE(writer->WritePackets(std::move(packets)));
  }

  std::string s;
  fseek(*f, 0, SEEK_SET);
  EXPECT_TRUE(base::ReadFileStream(*f, &s));
  EXPECT_GT(s.size(), 0u);

  protos::gen::Trace trace;
  EXPECT_TRUE(trace.ParseFromString(s));
}

TEST(PacketWriterTest, ZipPacketWriter_ShouldSplitPackets) {
  base::TempFile tmp = base::TempFile::CreateUnlinked();
  base::ScopedResource<FILE*, fclose, nullptr> f(
      fdopen(tmp.ReleaseFD().release(), "wb"));

  std::vector<perfetto::TracePacket> packets;

  for (uint32_t i = 0; i < 1000; i++) {
    packets.push_back(CreateTracePacket([i](TracePacketProto* msg) {
      auto* for_testing = msg->mutable_for_testing();
      for_testing->set_seq_value(i);
      for_testing->set_str(RandomString(1024));
    }));
  }

  {
    std::unique_ptr<PacketWriter> writer =
        CreateZipPacketWriter(CreateFilePacketWriter(*f));
    EXPECT_TRUE(writer->WritePackets(std::move(packets)));
  }

  std::string s;
  fseek(*f, 0, SEEK_SET);
  EXPECT_TRUE(base::ReadFileStream(*f, &s));
  EXPECT_GT(s.size(), 0u);

  protos::gen::Trace trace;
  EXPECT_TRUE(trace.ParseFromString(s));

  size_t packet_count = 0;
  for (const auto& packet : trace.packet()) {
    const std::string& data = packet.compressed_packets();
    EXPECT_GT(data.size(), 0u);
    EXPECT_LT(data.size(), 500 * 1024u);
    protos::gen::Trace subtrace;
    EXPECT_TRUE(subtrace.ParseFromString(Decompress(data)));
    for (const auto& subpacket : subtrace.packet()) {
      EXPECT_EQ(subpacket.for_testing().seq_value(), packet_count++);
    }
  }

  EXPECT_EQ(packet_count, 1000u);
}

#endif  // PERFETTO_BUILDFLAG(PERFETTO_ZLIB)

}  // namespace
}  // namespace perfetto