#include <iomanip>
#include <map>

#include "FWCore/Framework/interface/Event.h"
#include "FWCore/MessageLogger/interface/MessageLogger.h"
#include "FWCore/Utilities/interface/calculateCRC32.h"

#include "EventFilter/L1TRawToDigi/interface/AMC13Spec.h"

//#define EDM_ML_DEBUG 1

namespace amc13 {
  Header::Header(unsigned int namc, unsigned int orbit) {
    data_ = (static_cast<uint64_t>(namc & nAMC_mask) << nAMC_shift) |
            (static_cast<uint64_t>(orbit & OrN_mask) << OrN_shift) |
            (static_cast<uint64_t>(fov & uFOV_mask) << uFOV_shift);
  }

  bool Header::check() const { return (getNumberOfAMCs() <= max_amc) && (getFormatVersion() == fov); }

  Trailer::Trailer(unsigned int blk, unsigned int lv1, unsigned int bx) {
    data_ = (static_cast<uint64_t>(blk & BlkNo_mask) << BlkNo_shift) |
            (static_cast<uint64_t>(lv1 & LV1_mask) << LV1_shift) | (static_cast<uint64_t>(bx & BX_mask) << BX_shift);
  }

  bool Trailer::check(unsigned int crc, unsigned int block, unsigned int lv1_id, unsigned int bx) const {
    if ((crc != 0 && crc != getCRC()) || block != getBlock() || (lv1_id & LV1_mask) != getLV1ID() ||
        (bx & BX_mask) != getBX()) {
      edm::LogWarning("L1T") << "Found AMC13 trailer with:"
                             << "\n\tBX " << getBX() << ", LV1 ID " << getLV1ID() << ", block # " << getBlock()
                             << ", CRC " << std::hex << std::setw(8) << std::setfill('0') << getCRC() << std::dec
                             << "\nBut expected:"
                             << "\n\tBX " << (bx & BX_mask) << ", LV1 ID " << (lv1_id & LV1_mask) << ", block # "
                             << block << ", CRC " << std::hex << std::setw(8) << std::setfill('0') << crc;
      return false;
    }
    return true;
  }

  void Trailer::writeCRC(const uint64_t* start, uint64_t* end) {
    std::string_view dstring(reinterpret_cast<const char*>(start), reinterpret_cast<const char*>(end) + 4);
    auto crc = cms::calculateCRC32(dstring);

    *end = ((*end) & ~(uint64_t(CRC_mask) << CRC_shift)) | (static_cast<uint64_t>(crc & CRC_mask) << CRC_shift);
  }

  void Packet::add(unsigned int amc_no,
                   unsigned int board,
                   unsigned int lv1id,
                   unsigned int orbit,
                   unsigned int bx,
                   const std::vector<uint64_t>& load,
                   unsigned int user) {
    edm::LogInfo("AMC") << "Adding board " << board << " with payload size " << load.size() << " as payload #"
                        << amc_no;
    // Start by indexing with 1
    payload_.push_back(amc::Packet(amc_no, board, lv1id, orbit, bx, load, user));
  }

  bool Packet::parse(const uint64_t* start,
                     const uint64_t* data,
                     unsigned int size,
                     unsigned int lv1,
                     unsigned int bx,
                     bool legacy_mc,
                     bool mtf7_mode) {
    // Need at least a header and trailer
    // TODO check if this can be removed
    if (size < 2) {
      edm::LogError("AMC") << "AMC13 packet size too small";
      return false;
    }

    std::map<int, int> amc_index;

    header_ = Header(data++);

    if (!header_.check()) {
      edm::LogError("AMC") << "Invalid header for AMC13 packet: "
                           << "format version " << header_.getFormatVersion() << ", " << header_.getNumberOfAMCs()
                           << " AMC packets";
      return false;
    }

    if (size < 2 + header_.getNumberOfAMCs())
      return false;

    // Initial filling of AMC payloads.  First, get the headers.  The
    // first payload follows afterwards.
    for (unsigned int i = 0; i < header_.getNumberOfAMCs(); ++i) {
      payload_.push_back(amc::Packet(data++));
      amc_index[payload_.back().blockHeader().getAMCNumber()] = i;
    }

    unsigned int tot_size = 0;     // total payload size
    unsigned int tot_nblocks = 0;  // total blocks of payload
    unsigned int maxblocks = 0;    // counting the # of amc13 header/trailers (1 ea per block)

    bool check_crc = false;
    for (const auto& amc : payload_) {
      tot_size += amc.blockHeader().getSize();
      tot_nblocks += amc.blockHeader().getBlocks();
      maxblocks = std::max(maxblocks, amc.blockHeader().getBlocks());

      if (amc.blockHeader().validCRC())
        check_crc = true;
    }

    unsigned int words = tot_size +      // payload size
                         tot_nblocks +   // AMC headers
                         2 * maxblocks;  // AMC13 headers

    if (size < words) {
      edm::LogError("L1T") << "Encountered AMC 13 packet with " << size << " words, "
                           << "but expected " << words << " words: " << tot_size << " payload words, " << tot_nblocks
                           << " AMC header words, and 2 AMC 13 header words.";
      return false;
    }

    // Read in the first AMC block and append the payload to the
    // corresponding AMC packet.
    for (auto& amc : payload_) {
      amc.addPayload(data, amc.blockHeader().getBlockSize());
      data += amc.blockHeader().getBlockSize();
    }

    Trailer t(data++);

    int crc = 0;
    if (check_crc) {
      std::string_view check(reinterpret_cast<const char*>(start), reinterpret_cast<const char*>(data) - 4);
      crc = cms::calculateCRC32(check);

      LogDebug("L1T") << "checking data checksum of " << std::hex << crc << std::dec;
    }

    t.check(crc, 0, lv1, bx);

    // Read in remaining AMC blocks
    for (unsigned int b = 1; b < maxblocks; ++b) {
      Header block_h(data++);
      std::vector<amc::BlockHeader> headers;

      for (unsigned int i = 0; i < block_h.getNumberOfAMCs(); ++i)
        headers.push_back(amc::BlockHeader(data++));

      check_crc = false;
      for (const auto& amc : headers) {
        payload_[amc_index[amc.getAMCNumber()]].addPayload(data, amc.getBlockSize());
        data += amc.getBlockSize();

        if (amc.validCRC())
          check_crc = true;
      }

      t = Trailer(data++);

      if (check_crc) {
        std::string_view check(reinterpret_cast<const char*>(start), reinterpret_cast<const char*>(data) - 4);
        crc = cms::calculateCRC32(check);

        LogDebug("L1T") << "checking data checksum of " << std::hex << crc << std::dec;
      } else {
        crc = 0;
      }

      t.check(crc, b, lv1, bx);
    }

    for (auto& amc : payload_) {
      amc.finalize(lv1, bx, legacy_mc, mtf7_mode);
    }

    return true;
  }

  unsigned int Packet::blocks() const {
    unsigned int maxblocks = 0;

    for (const auto& amc : payload_)
      maxblocks = std::max(maxblocks, amc.blocks());

    return maxblocks;
  }

  unsigned int Packet::size() const {
    unsigned int words = 0;
    unsigned int blocks = 0;
    unsigned int maxblocks = 0;

    for (const auto& amc : payload_) {
      words += amc.header().getSize();
      blocks += amc.blocks();
      maxblocks = std::max(maxblocks, amc.blocks());
    }

    // Size is total amount of words + # of blocks for AMC headers + # of
    // maxblocks for AMC13 block header, trailer
    return words + blocks + maxblocks * 2;
  }

  bool Packet::write(const edm::Event& ev, unsigned char* ptr, unsigned int skip, unsigned int size) const {
    if (size < this->size() * 8)
      return false;

    if (size % 8 != 0)
      return false;

    uint64_t* data = reinterpret_cast<uint64_t*>(ptr + skip);

    for (unsigned int b = 0; b < blocks(); ++b) {
      // uint64_t * block_start = data;

      std::vector<uint64_t> block_headers;
      std::vector<uint64_t> block_load;
      for (const auto& amc : payload_) {
        edm::LogInfo("AMC") << "Considering block " << b << " for payload " << amc.blockHeader().getBoardID()
                            << " with size " << amc.size() << " and " << amc.blocks() << " blocks";
        if (amc.blocks() < b + 1)
          continue;

        block_headers.push_back(amc.blockHeader(b));
        auto words = amc.block(b);
        block_load.insert(block_load.end(), words.begin(), words.end());
      }

      if (b == 0) {
        amc13::Header h(block_headers.size(), ev.orbitNumber());
        edm::LogInfo("AMC") << "Writing header for AMC13 packet: "
                            << "format version " << h.getFormatVersion() << ", " << h.getNumberOfAMCs()
                            << " AMC packets, orbit " << h.getOrbitNumber();
      }

      *(data++) = amc13::Header(block_headers.size(), ev.orbitNumber()).raw();

      block_headers.insert(block_headers.end(), block_load.begin(), block_load.end());
      for (const auto& word : block_headers)
        *(data++) = word;

      *data = Trailer(b, ev.id().event(), ev.bunchCrossing()).raw();
      Trailer::writeCRC(reinterpret_cast<uint64_t*>(ptr), data);
    }

    return true;
  }
}  // namespace amc13