/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "sdp/Sdp.h"
#include "sdp/ParsingResultComparer.h"
#include "sdp/SipccSdpParser.h"
#include "sdp/RsdparsaSdpParser.h"
#include "sdp/SdpTelemetry.h"

#include <string>
#include <ostream>
#include <regex>

#include "mozilla/Assertions.h"
#include "mozilla/Telemetry.h"
#include "mozilla/Logging.h"

using mozilla::LogLevel;
static mozilla::LazyLogModule sSdpDiffLogger("sdpdiff_logger");

#define LOGD(msg) MOZ_LOG(sSdpDiffLogger, LogLevel::Debug, msg)
#define LOGE(msg) MOZ_LOG(sSdpDiffLogger, LogLevel::Error, msg)

#define LOG_EXPECT(result, expect, msg)                         \
  {                                                             \
    if (((expect) == SdpComparisonResult::Equal) == (result)) { \
      LOGD(msg);                                                \
    } else {                                                    \
      LOGE(("UNEXPECTED COMPARISON RESULT: vvvvvv"));           \
      LOGE(msg);                                                \
    }                                                           \
  }

namespace mozilla {

using AttributeType = SdpAttribute::AttributeType;

template <typename T>
std::string ToString(const T& serializable) {
  std::ostringstream os;

  os << serializable;
  return os.str();
}
bool ParsingResultComparer::Compare(const Results& aResA, const Results& aResB,
                                    const std::string& aOriginalSdp,
                                    const SdpPref::AlternateParseModes& aMode) {
  MOZ_ASSERT(aResA, "aResA must not be a nullptr");
  MOZ_ASSERT(aResB, "aResB must not be a nullptr");
  MOZ_ASSERT(aResA->ParserName() != aResB->ParserName(),
             "aResA and aResB must be from different parsers");
  SdpTelemetry::RecordCompare(aResA, aResB, aMode);

  ParsingResultComparer comparer;
  if (!aResA->Sdp() || !aResB->Sdp()) {
    return !aResA->Sdp() && !aResB->Sdp();
  }
  if (SipccSdpParser::IsNamed(aResA->ParserName())) {
    MOZ_ASSERT(RsdparsaSdpParser::IsNamed(aResB->ParserName()));
    return comparer.Compare(*aResB->Sdp(), *aResA->Sdp(), aOriginalSdp,
                            SdpComparisonResult::Equal);
  }
  MOZ_ASSERT(SipccSdpParser::IsNamed(aResB->ParserName()));
  MOZ_ASSERT(RsdparsaSdpParser::IsNamed(aResA->ParserName()));
  return comparer.Compare(*aResA->Sdp(), *aResB->Sdp(), aOriginalSdp,
                          SdpComparisonResult::Equal);
}

bool ParsingResultComparer::Compare(const Sdp& rsdparsaSdp, const Sdp& sipccSdp,
                                    const std::string& originalSdp,
                                    const SdpComparisonResult expect) {
  mOriginalSdp = originalSdp;
  const std::string sipccSdpStr = sipccSdp.ToString();
  const std::string rsdparsaSdpStr = rsdparsaSdp.ToString();

  bool result = rsdparsaSdpStr == sipccSdpStr;
  LOG_EXPECT(result, expect, ("The original sdp: \n%s", mOriginalSdp.c_str()));
  if (result) {
    Telemetry::ScalarAdd(Telemetry::ScalarID::WEBRTC_SDP_PARSER_DIFF,
                         u"serialization_is_equal"_ns, 1);
    LOG_EXPECT(result, expect, ("Serialization is equal"));
    return result;
  }
  // Do a deep comparison
  result = true;

  Telemetry::ScalarAdd(Telemetry::ScalarID::WEBRTC_SDP_PARSER_DIFF,
                       u"serialization_is_not_equal"_ns, 1);
  LOG_EXPECT(result, expect,
             ("Serialization is not equal\n"
              " --- Sipcc SDP ---\n"
              "%s\n"
              "--- Rsdparsa SDP ---\n"
              "%s\n",
              sipccSdpStr.c_str(), rsdparsaSdpStr.c_str()));

  const std::string rsdparsaOriginStr = ToString(rsdparsaSdp.GetOrigin());
  const std::string sipccOriginStr = ToString(sipccSdp.GetOrigin());

  // Compare the session level
  if (rsdparsaOriginStr != sipccOriginStr) {
    Telemetry::ScalarAdd(Telemetry::ScalarID::WEBRTC_SDP_PARSER_DIFF, u"o="_ns,
                         1);
    result = false;
    LOG_EXPECT(result, expect,
               ("origin is not equal\nrust origin: %s\nsipcc origin: %s",
                rsdparsaOriginStr.c_str(), sipccOriginStr.c_str()));
  }

  if (MOZ_LOG_TEST(sSdpDiffLogger, LogLevel::Debug)) {
    const auto rust_sess_attr_count = rsdparsaSdp.GetAttributeList().Count();
    const auto sipcc_sess_attr_count = sipccSdp.GetAttributeList().Count();

    if (rust_sess_attr_count != sipcc_sess_attr_count) {
      LOG_EXPECT(false, expect,
                 ("Session level attribute count is NOT equal, rsdparsa: %u, "
                  "sipcc: %u\n",
                  rust_sess_attr_count, sipcc_sess_attr_count));
    }
  }

  result &= CompareAttrLists(rsdparsaSdp.GetAttributeList(),
                             sipccSdp.GetAttributeList(), -1);

  const uint32_t sipccMediaSecCount =
      static_cast<uint32_t>(sipccSdp.GetMediaSectionCount());
  const uint32_t rsdparsaMediaSecCount =
      static_cast<uint32_t>(rsdparsaSdp.GetMediaSectionCount());

  if (sipccMediaSecCount != rsdparsaMediaSecCount) {
    result = false;
    Telemetry::ScalarAdd(Telemetry::ScalarID::WEBRTC_SDP_PARSER_DIFF,
                         u"inequal_msec_count"_ns, 1);
    LOG_EXPECT(result, expect,
               ("Media section count is NOT equal, rsdparsa: %d, sipcc: %d \n",
                rsdparsaMediaSecCount, sipccMediaSecCount));
  }

  for (size_t i = 0; i < std::min(sipccMediaSecCount, rsdparsaMediaSecCount);
       i++) {
    result &= CompareMediaSections(rsdparsaSdp.GetMediaSection(i),
                                   sipccSdp.GetMediaSection(i));
  }

  return result;
}

bool ParsingResultComparer::CompareMediaSections(
    const SdpMediaSection& rustMediaSection,
    const SdpMediaSection& sipccMediaSection,
    const SdpComparisonResult expect) const {
  bool result = true;
  auto trackMediaLineMismatch = [&result, &expect](
                                    auto rustValue, auto sipccValue,
                                    const nsString& valueDescription) {
    result = false;
    nsString typeStr = u"m="_ns;
    typeStr += valueDescription;
    Telemetry::ScalarAdd(Telemetry::ScalarID::WEBRTC_SDP_PARSER_DIFF, typeStr,
                         1);
    LOG_EXPECT(result, expect,
               ("The media line values %s are not equal\n"
                "rsdparsa value: %s\n"
                "sipcc value: %s\n",
                NS_LossyConvertUTF16toASCII(valueDescription).get(),
                ToString(rustValue).c_str(), ToString(sipccValue).c_str()));
  };

  auto compareMediaLineValue = [trackMediaLineMismatch](
                                   auto rustValue, auto sipccValue,
                                   const nsString& valueDescription) {
    if (rustValue != sipccValue) {
      trackMediaLineMismatch(rustValue, sipccValue, valueDescription);
    }
  };

  auto compareSimpleMediaLineValue =
      [&rustMediaSection, &sipccMediaSection, compareMediaLineValue](
          auto valGetFuncPtr, const nsString& valueDescription) {
        compareMediaLineValue((rustMediaSection.*valGetFuncPtr)(),
                              (sipccMediaSection.*valGetFuncPtr)(),
                              valueDescription);
      };

  compareSimpleMediaLineValue(&SdpMediaSection::GetMediaType, u"media_type"_ns);
  compareSimpleMediaLineValue(&SdpMediaSection::GetPort, u"port"_ns);
  compareSimpleMediaLineValue(&SdpMediaSection::GetPortCount, u"port_count"_ns);
  compareSimpleMediaLineValue(&SdpMediaSection::GetProtocol, u"protocol"_ns);
  compareSimpleMediaLineValue(&SdpMediaSection::IsReceiving,
                              u"is_receiving"_ns);
  compareSimpleMediaLineValue(&SdpMediaSection::IsSending, u"is_sending"_ns);
  compareSimpleMediaLineValue(&SdpMediaSection::GetDirection, u"direction"_ns);
  compareSimpleMediaLineValue(&SdpMediaSection::GetLevel, u"level"_ns);

  compareMediaLineValue(ToString(rustMediaSection.GetConnection()),
                        ToString(sipccMediaSection.GetConnection()),
                        u"connection"_ns);

  result &= CompareAttrLists(rustMediaSection.GetAttributeList(),
                             sipccMediaSection.GetAttributeList(),
                             static_cast<int>(rustMediaSection.GetLevel()));
  return result;
}

bool ParsingResultComparer::CompareAttrLists(
    const SdpAttributeList& rustAttrlist, const SdpAttributeList& sipccAttrlist,
    int level, const SdpComparisonResult expect) const {
  bool result = true;

  for (size_t i = AttributeType::kFirstAttribute;
       i <= static_cast<size_t>(AttributeType::kLastAttribute); i++) {
    const AttributeType type = static_cast<AttributeType>(i);
    std::string attrStr;
    if (type != AttributeType::kDirectionAttribute) {
      attrStr = "a=" + SdpAttribute::GetAttributeTypeString(type);
    } else {
      attrStr = "a=_direction_attribute_";
    }

    if (sipccAttrlist.HasAttribute(type, false)) {
      auto sipccAttrStr = ToString(*sipccAttrlist.GetAttribute(type, false));

      if (!rustAttrlist.HasAttribute(type, false)) {
        result = false;
        nsString typeStr;
        typeStr.AssignASCII(attrStr.c_str());
        typeStr += u"_missing"_ns;
        Telemetry::ScalarAdd(Telemetry::ScalarID::WEBRTC_SDP_PARSER_DIFF,
                             typeStr, 1);
        LOG_EXPECT(result, expect,
                   ("Rust is missing the attribute: %s\n", attrStr.c_str()));
        LOG_EXPECT(result, expect,
                   ("Rust is missing: %s\n", sipccAttrStr.c_str()));

        continue;
      }

      auto rustAttrStr = ToString(*rustAttrlist.GetAttribute(type, false));

      if (rustAttrStr != sipccAttrStr) {
        if (type == AttributeType::kFmtpAttribute) {
          if (rustAttrlist.GetFmtp() == sipccAttrlist.GetFmtp()) {
            continue;
          }
        }

        std::string originalAttrStr = GetAttributeLines(attrStr, level);
        if (rustAttrStr != originalAttrStr) {
          result = false;
          nsString typeStr;
          typeStr.AssignASCII(attrStr.c_str());
          typeStr += u"_inequal"_ns;
          Telemetry::ScalarAdd(Telemetry::ScalarID::WEBRTC_SDP_PARSER_DIFF,
                               typeStr, 1);
          LOG_EXPECT(result, expect,
                     ("%s is neither equal to sipcc nor to the orginal sdp\n"
                      "--------------rsdparsa attribute---------------\n"
                      "%s"
                      "--------------sipcc attribute---------------\n"
                      "%s"
                      "--------------original attribute---------------\n"
                      "%s\n",
                      attrStr.c_str(), rustAttrStr.c_str(),
                      sipccAttrStr.c_str(), originalAttrStr.c_str()));
        } else {
          LOG_EXPECT(
              result, expect,
              ("But the rust serialization is equal to the orignal sdp\n"));
        }
      }
    } else {
      if (rustAttrlist.HasAttribute(type, false)) {
        nsString typeStr;
        typeStr.AssignASCII(attrStr.c_str());
        typeStr += u"_unexpected"_ns;
        Telemetry::ScalarAdd(Telemetry::ScalarID::WEBRTC_SDP_PARSER_DIFF,
                             typeStr, 1);
      }
    }
  }

  return result;
}

std::vector<std::string> SplitLines(const std::string& sdp) {
  std::stringstream ss(sdp);
  std::string to;
  std::vector<std::string> lines;

  while (std::getline(ss, to, '\n')) {
    lines.push_back(to);
  }

  return lines;
}

std::string ParsingResultComparer::GetAttributeLines(
    const std::string& attrType, int level) const {
  std::vector<std::string> lines = SplitLines(mOriginalSdp);
  std::string attrToFind = attrType + ":";
  std::string attrLines;
  int currentLevel = -1;
  // Filters rtcp-fb lines that contain "x-..." types
  // This is because every SDP from Edge contains these rtcp-fb x- types
  // for example: a=rtcp-fb:121 x-foo
  std::regex customRtcpFbLines(R"(a\=rtcp\-fb\:(\d+|\*).* x\-.*)");

  for (auto& line : lines) {
    if (line.find("m=") == 0) {
      if (level > currentLevel) {
        attrLines.clear();
        currentLevel++;
      } else {
        break;
      }
    } else if (line.find(attrToFind) == 0) {
      if (std::regex_match(line, customRtcpFbLines)) {
        continue;
      }

      attrLines += (line + '\n');
    }
  }

  return attrLines;
}

}  // namespace mozilla