/*
 *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#include "modules/rtp_rtcp/source/rtcp_packet/bye.h"

#include <cstddef>
#include <cstdint>
#include <string>
#include <vector>

#include "rtc_base/buffer.h"
#include "test/gmock.h"
#include "test/gtest.h"
#include "test/rtcp_packet_parser.h"

using ::testing::ElementsAre;
using webrtc::rtcp::Bye;

namespace webrtc {
namespace {
constexpr uint32_t kSenderSsrc = 0x12345678;
constexpr uint32_t kCsrc1 = 0x22232425;
constexpr uint32_t kCsrc2 = 0x33343536;
}  // namespace

TEST(RtcpPacketByeTest, CreateAndParseWithoutReason) {
  Bye bye;
  bye.SetSenderSsrc(kSenderSsrc);

  Buffer raw = bye.Build();
  Bye parsed_bye;
  EXPECT_TRUE(test::ParseSinglePacket(raw, &parsed_bye));

  EXPECT_EQ(kSenderSsrc, parsed_bye.sender_ssrc());
  EXPECT_TRUE(parsed_bye.csrcs().empty());
  EXPECT_TRUE(parsed_bye.reason().empty());
}

TEST(RtcpPacketByeTest, CreateAndParseWithCsrcs) {
  Bye bye;
  bye.SetSenderSsrc(kSenderSsrc);
  EXPECT_TRUE(bye.SetCsrcs({kCsrc1, kCsrc2}));
  EXPECT_TRUE(bye.reason().empty());

  Buffer raw = bye.Build();
  Bye parsed_bye;
  EXPECT_TRUE(test::ParseSinglePacket(raw, &parsed_bye));

  EXPECT_EQ(kSenderSsrc, parsed_bye.sender_ssrc());
  EXPECT_THAT(parsed_bye.csrcs(), ElementsAre(kCsrc1, kCsrc2));
  EXPECT_TRUE(parsed_bye.reason().empty());
}

TEST(RtcpPacketByeTest, CreateAndParseWithCsrcsAndAReason) {
  Bye bye;
  const std::string kReason = "Some Reason";

  bye.SetSenderSsrc(kSenderSsrc);
  EXPECT_TRUE(bye.SetCsrcs({kCsrc1, kCsrc2}));
  bye.SetReason(kReason);

  Buffer raw = bye.Build();
  Bye parsed_bye;
  EXPECT_TRUE(test::ParseSinglePacket(raw, &parsed_bye));

  EXPECT_EQ(kSenderSsrc, parsed_bye.sender_ssrc());
  EXPECT_THAT(parsed_bye.csrcs(), ElementsAre(kCsrc1, kCsrc2));
  EXPECT_EQ(kReason, parsed_bye.reason());
}

TEST(RtcpPacketByeTest, CreateWithTooManyCsrcs) {
  Bye bye;
  bye.SetSenderSsrc(kSenderSsrc);
  const int kMaxCsrcs = (1 << 5) - 2;  // 5 bit len, first item is sender SSRC.
  EXPECT_TRUE(bye.SetCsrcs(std::vector<uint32_t>(kMaxCsrcs, kCsrc1)));
  EXPECT_FALSE(bye.SetCsrcs(std::vector<uint32_t>(kMaxCsrcs + 1, kCsrc1)));
}

TEST(RtcpPacketByeTest, CreateAndParseWithAReason) {
  Bye bye;
  const std::string kReason = "Some Random Reason";

  bye.SetSenderSsrc(kSenderSsrc);
  bye.SetReason(kReason);

  Buffer raw = bye.Build();
  Bye parsed_bye;
  EXPECT_TRUE(test::ParseSinglePacket(raw, &parsed_bye));

  EXPECT_EQ(kSenderSsrc, parsed_bye.sender_ssrc());
  EXPECT_TRUE(parsed_bye.csrcs().empty());
  EXPECT_EQ(kReason, parsed_bye.reason());
}

TEST(RtcpPacketByeTest, CreateAndParseWithReasons) {
  // Test that packet creation/parsing behave with reasons of different length
  // both when it require padding and when it does not.
  for (size_t reminder = 0; reminder < 4; ++reminder) {
    const std::string kReason(4 + reminder, 'a' + reminder);
    Bye bye;
    bye.SetSenderSsrc(kSenderSsrc);
    bye.SetReason(kReason);

    Buffer raw = bye.Build();
    Bye parsed_bye;
    EXPECT_TRUE(test::ParseSinglePacket(raw, &parsed_bye));

    EXPECT_EQ(kReason, parsed_bye.reason());
  }
}

TEST(RtcpPacketByeTest, ParseEmptyPacket) {
  uint8_t kEmptyPacket[] = {0x80, Bye::kPacketType, 0, 0};
  Bye parsed_bye;
  EXPECT_TRUE(test::ParseSinglePacket(kEmptyPacket, &parsed_bye));
  EXPECT_EQ(0u, parsed_bye.sender_ssrc());
  EXPECT_TRUE(parsed_bye.csrcs().empty());
  EXPECT_TRUE(parsed_bye.reason().empty());
}

TEST(RtcpPacketByeTest, ParseFailOnInvalidSrcCount) {
  Bye bye;
  bye.SetSenderSsrc(kSenderSsrc);

  Buffer raw = bye.Build();
  raw[0]++;  // Damage the packet: increase ssrc count by one.

  Bye parsed_bye;
  EXPECT_FALSE(test::ParseSinglePacket(raw, &parsed_bye));
}

TEST(RtcpPacketByeTest, ParseFailOnInvalidReasonLength) {
  Bye bye;
  bye.SetSenderSsrc(kSenderSsrc);
  bye.SetReason("18 characters long");

  Buffer raw = bye.Build();
  // Damage the packet: decrease payload size by 4 bytes
  raw[3]--;
  raw.SetSize(raw.size() - 4);

  Bye parsed_bye;
  EXPECT_FALSE(test::ParseSinglePacket(raw, &parsed_bye));
}

}  // namespace webrtc