//
// $Id: LogErrorEventFilter.cc,v 1.4 2013/04/09 10:06:10 davidlt Exp $
//

/**
  \class    gLogErrorEventFilter PATMuonKinematics.h "PhysicsTools/PatAlgos/interface/PATMuonKinematics.h"
  \brief    Use StandAlone track to define the 4-momentum of a PAT Muon (normally the global one is used)
            
  \author   Giovanni Petrucciani
*/

#include "FWCore/Framework/interface/global/EDFilter.h"
#include "FWCore/Framework/interface/Event.h"
#include "FWCore/Framework/interface/Run.h"
#include "FWCore/Framework/interface/LuminosityBlock.h"
#include "FWCore/ParameterSet/interface/ParameterSet.h"
#include "FWCore/Utilities/interface/InputTag.h"

#include "DataFormats/Common/interface/ErrorSummaryEntry.h"

#include <map>
#include <set>
#include <string>
#include <iomanip>
#include <iostream>
#include <iterator>

namespace leef {
  using Error = edm::ErrorSummaryEntry;
  struct ErrorSort {
    bool operator()(const Error &e1, const Error &e2) const {
      if (e1.severity.getLevel() != e2.severity.getLevel())
        return e1.severity.getLevel() > e2.severity.getLevel();
      if (e1.module != e2.module)
        return e1.module < e2.module;
      if (e1.category != e2.category)
        return e1.category < e2.category;
      return false;
    }
  };
  using ErrorSet = std::set<edm::ErrorSummaryEntry, ErrorSort>;

  struct RunErrors {
    RunErrors() : npass_{0}, nfail_{0}, collectionGuard_{false} {}
    //Errors should be sufficiently infrequent so that the use of a
    // spin lock on a thread-unsafe container should not pose a
    // performance problem
    CMS_THREAD_GUARD(collectionGuard_) mutable ErrorSet errorCollection_;
    mutable std::atomic<size_t> npass_;
    mutable std::atomic<size_t> nfail_;

    mutable std::atomic<bool> collectionGuard_;
  };

  struct LumiErrors {
    LumiErrors() : npass_{0}, nfail_{0}, collectionGuard_{false} {}

    CMS_THREAD_GUARD(collectionGuard_) mutable ErrorSet errorCollection_;
    mutable std::atomic<size_t> npass_;
    mutable std::atomic<size_t> nfail_;

    mutable std::atomic<bool> collectionGuard_;
  };
}  // namespace leef

namespace {
  //Use std::unique_ptr to guarantee that the use of an atomic
  // as a spin lock will get reset to false
  struct release {
    void operator()(std::atomic<bool> *b) const noexcept { b->store(false); }
  };
  std::unique_ptr<std::atomic<bool>, release> make_guard(std::atomic<bool> &b) noexcept {
    bool expected = false;
    while (not b.compare_exchange_strong(expected, true)) {
      expected = false;
    }
    return std::unique_ptr<std::atomic<bool>, release>(&b, release());
  }

}  // namespace

using namespace leef;

class LogErrorEventFilter : public edm::global::EDFilter<edm::RunCache<leef::RunErrors>,
                                                         edm::LuminosityBlockCache<LumiErrors>,
                                                         edm::EndLuminosityBlockProducer> {
public:
  explicit LogErrorEventFilter(const edm::ParameterSet &iConfig);
  ~LogErrorEventFilter() override {}

  bool filter(edm::StreamID, edm::Event &iEvent, const edm::EventSetup &iSetup) const override;
  std::shared_ptr<LumiErrors> globalBeginLuminosityBlock(const edm::LuminosityBlock &lumi,
                                                         const edm::EventSetup &iSetup) const override;
  void globalEndLuminosityBlock(const edm::LuminosityBlock &lumi, const edm::EventSetup &iSetup) const override;
  void globalEndLuminosityBlockProduce(edm::LuminosityBlock &lumi, const edm::EventSetup &iSetup) const override;
  std::shared_ptr<RunErrors> globalBeginRun(const edm::Run &run, const edm::EventSetup &iSetup) const override;
  void globalEndRun(const edm::Run &run, const edm::EventSetup &iSetup) const override;
  void endJob() override;

private:
  typedef edm::ErrorSummaryEntry Error;
  typedef std::vector<edm::ErrorSummaryEntry> ErrorList;

  edm::InputTag src_;
  edm::EDGetTokenT<ErrorList> srcT_;
  bool readSummaryMode_;
  std::set<std::string> modulesToWatch_;
  std::set<std::string> modulesToIgnore_;
  std::set<std::string> categoriesToWatch_;
  std::set<std::string> categoriesToIgnore_;
  CMS_THREAD_GUARD(statsGuard_)
  mutable std::map<std::pair<uint32_t, uint32_t>, std::pair<size_t, size_t> > statsPerLumi_;
  CMS_THREAD_GUARD(statsGuard_) mutable std::map<uint32_t, std::pair<size_t, size_t> > statsPerRun_;
  CMS_THREAD_GUARD(statsGuard_) mutable ErrorSet errorCollectionAll_;
  double thresholdPerLumi_, thresholdPerRun_;
  size_t maxSavedEventsPerLumi_;
  bool verbose_, veryVerbose_;
  bool taggedMode_, forcedValue_;
  mutable std::atomic<bool> statsGuard_{false};

  template <typename Collection>
  static void increment(ErrorSet &scoreboard, Collection &list);
  template <typename Collection>
  static void print(const Collection &errors);

  static std::unique_ptr<ErrorList> serialize(const ErrorSet &set) {
    return std::make_unique<ErrorList>(set.begin(), set.end());
  }
};

LogErrorEventFilter::LogErrorEventFilter(const edm::ParameterSet &iConfig)
    : src_(iConfig.getParameter<edm::InputTag>("src")),
      srcT_(consumes<ErrorList>(iConfig.getParameter<edm::InputTag>("src"))),
      readSummaryMode_(iConfig.existsAs<bool>("readSummaryMode") ? iConfig.getParameter<bool>("readSummaryMode")
                                                                 : false),
      thresholdPerLumi_(iConfig.getParameter<double>("maxErrorFractionInLumi")),
      thresholdPerRun_(iConfig.getParameter<double>("maxErrorFractionInRun")),
      maxSavedEventsPerLumi_(iConfig.getParameter<uint32_t>("maxSavedEventsPerLumiAndError")),
      verbose_(iConfig.getUntrackedParameter<bool>("verbose", false)),
      veryVerbose_(iConfig.getUntrackedParameter<bool>("veryVerbose", false)),
      taggedMode_(iConfig.getUntrackedParameter<bool>("taggedMode", false)),
      forcedValue_(iConfig.getUntrackedParameter<bool>("forcedValue", true)) {
  produces<ErrorList, edm::Transition::EndLuminosityBlock>();
  produces<int, edm::Transition::EndLuminosityBlock>("pass");
  produces<int, edm::Transition::EndLuminosityBlock>("fail");
  //produces<ErrorList, edm::InRun>();
  produces<bool>();

  if (iConfig.existsAs<std::vector<std::string> >("modulesToWatch")) {
    std::vector<std::string> modules = iConfig.getParameter<std::vector<std::string> >("modulesToWatch");
    if (!(modules.size() == 1 && modules[0] == "*")) {
      modulesToWatch_.insert(modules.begin(), modules.end());
    }
  }
  if (iConfig.existsAs<std::vector<std::string> >("modulesToIgnore")) {
    std::vector<std::string> modules = iConfig.getParameter<std::vector<std::string> >("modulesToIgnore");
    if (!(modules.size() == 1 && modules[0] == "*")) {
      modulesToIgnore_.insert(modules.begin(), modules.end());
    }
  }
  if (iConfig.existsAs<std::vector<std::string> >("categoriesToWatch")) {
    std::vector<std::string> categories = iConfig.getParameter<std::vector<std::string> >("categoriesToWatch");
    if (!(categories.size() == 1 && categories[0] == "*")) {
      categoriesToWatch_.insert(categories.begin(), categories.end());
    }
  }
  if (iConfig.existsAs<std::vector<std::string> >("categoriesToIgnore")) {
    std::vector<std::string> categories = iConfig.getParameter<std::vector<std::string> >("categoriesToIgnore");
    if (!(categories.size() == 1 && categories[0] == "*")) {
      categoriesToIgnore_.insert(categories.begin(), categories.end());
    }
  }
  //std::ostream_iterator<std::string> dump(std::cout, ", ");
  //std::cout << "\nWatch modules:     " ; std::copy(modulesToWatch_.begin(),     modulesToWatch_.end(),     dump);
  //std::cout << "\nIgnore modules:    " ; std::copy(modulesToIgnore_.begin(),    modulesToIgnore_.end(),    dump);
  //std::cout << "\nIgnore categories: " ; std::copy(categoriesToIgnore_.begin(), categoriesToIgnore_.end(), dump);
  //std::cout << "\nWatch categories:  " ; std::copy(categoriesToWatch_.begin(),  categoriesToWatch_.end(),  dump);
  //std::cout << std::endl;
}

std::shared_ptr<LumiErrors> LogErrorEventFilter::globalBeginLuminosityBlock(const edm::LuminosityBlock &lumi,
                                                                            const edm::EventSetup &iSetup) const {
  auto ret = std::make_shared<LumiErrors>();
  if (readSummaryMode_) {
    edm::Handle<ErrorList> handle;
    edm::Handle<int> hpass, hfail;
    lumi.getByLabel(src_, handle);
    lumi.getByLabel(edm::InputTag(src_.label(), "pass", src_.process()), hpass);
    lumi.getByLabel(edm::InputTag(src_.label(), "fail", src_.process()), hfail);
    increment(ret->errorCollection_, *handle);
    ret->npass_ = *hpass;
    ret->nfail_ = *hfail;

    auto runC = runCache(lumi.getRun().index());
    runC->npass_ += *hpass;
    runC->nfail_ += *hfail;
  }
  return ret;
}
void LogErrorEventFilter::globalEndLuminosityBlock(edm::LuminosityBlock const &lumi,
                                                   const edm::EventSetup &iSetup) const {
  auto lumiC = luminosityBlockCache(lumi.index());
  auto nfail = lumiC->nfail_.load();
  auto npass = lumiC->npass_.load();
  {
    auto guard = make_guard(statsGuard_);
    statsPerLumi_[std::pair<uint32_t, uint32_t>(lumi.run(), lumi.luminosityBlock())] =
        std::pair<size_t, size_t>(npass, nfail);
  }
  {
    //synchronize lumiC->errorCollection_
    auto guard = make_guard(lumiC->collectionGuard_);

    {
      if (nfail < thresholdPerLumi_ * (npass + nfail)) {
        //synchronize runC->errorCollection_
        auto runC = runCache(lumi.getRun().index());
        auto guard = make_guard(runC->collectionGuard_);
        increment(runC->errorCollection_, lumiC->errorCollection_);
      }
    }
    if (verbose_) {
      if (!lumiC->errorCollection_.empty()) {
        std::cout << "\n === REPORT FOR RUN " << lumi.run() << " LUMI " << lumi.luminosityBlock()
                  << " === " << std::endl;
        print(lumiC->errorCollection_);
      }
    }
  }
}

void LogErrorEventFilter::globalEndLuminosityBlockProduce(edm::LuminosityBlock &lumi,
                                                          const edm::EventSetup &iSetup) const {
  auto lumiC = luminosityBlockCache(lumi.index());
  {
    //synchronize errorCollection_
    auto guard = make_guard(lumiC->collectionGuard_);
    lumi.put(serialize(lumiC->errorCollection_));
  }
  lumi.put(std::make_unique<int>(lumiC->npass_.load()), "pass");
  lumi.put(std::make_unique<int>(lumiC->nfail_.load()), "fail");
}

std::shared_ptr<RunErrors> LogErrorEventFilter::globalBeginRun(const edm::Run &run,
                                                               const edm::EventSetup &iSetup) const {
  return std::make_shared<RunErrors>();
}

void LogErrorEventFilter::globalEndRun(const edm::Run &run, const edm::EventSetup &iSetup) const {
  auto runC = runCache(run.index());
  auto npass = runC->npass_.load();
  auto nfail = runC->nfail_.load();
  {
    auto guard = make_guard(statsGuard_);
    statsPerRun_[run.run()] = std::pair<size_t, size_t>(npass, nfail);
  }
  {
    //synchronize errorCollection_
    auto guard = make_guard(runC->collectionGuard_);
    if (nfail < thresholdPerRun_ * (npass + nfail)) {
      auto guard = make_guard(statsGuard_);
      increment(errorCollectionAll_, runC->errorCollection_);
    }
    if (verbose_) {
      if (!runC->errorCollection_.empty()) {
        std::cout << "\n === REPORT FOR RUN " << run.run() << " === " << std::endl;
        print(runC->errorCollection_);
      }
    }
  }
}

void LogErrorEventFilter::endJob() {
  if (verbose_) {
    std::cout << "\n === REPORT FOR JOB === " << std::endl;
    //synchronizes statsPerRun_ and errorCollectionAll_
    auto guard = make_guard(statsGuard_);
    print(errorCollectionAll_);

    typedef std::pair<size_t, size_t> counter;

    std::cout << "\n === SCOREBOARD PER RUN === " << std::endl;
    typedef std::pair<uint32_t, counter> hitRun;
    for (auto const &hit : statsPerRun_) {
      double fract = hit.second.second / double(hit.second.first + hit.second.second);
      printf("run %6d: fail %7zu, pass %7zu, fraction %7.3f%%%s\n",
             hit.first,
             hit.second.second,
             hit.second.first,
             fract * 100.,
             (fract >= thresholdPerRun_ ? " (run excluded from summary list)" : ""));
    }

    std::cout << "\n === SCOREBOARD PER LUMI === " << std::endl;
    typedef std::pair<std::pair<uint32_t, uint32_t>, counter> hitLumi;
    for (auto const &hit : statsPerLumi_) {
      double fract = hit.second.second / double(hit.second.first + hit.second.second);
      printf("run %6d, lumi %4d: fail %zu, pass %zu, fraction %7.3f%%%s\n",
             hit.first.first,
             hit.first.second,
             hit.second.second,
             hit.second.first,
             fract * 100.,
             (fract >= thresholdPerLumi_ ? " (lumi excluded from run list)" : ""));
    }
  }
}

bool LogErrorEventFilter::filter(edm::StreamID, edm::Event &iEvent, const edm::EventSetup &iSetup) const {
  if (readSummaryMode_)
    return true;

  bool fail = false, save = false;

  edm::Handle<ErrorList> errors;
  iEvent.getByToken(srcT_, errors);

  auto runC = runCache(iEvent.getRun().index());
  auto lumiC = luminosityBlockCache(iEvent.getLuminosityBlock().index());

  if (errors->empty()) {
    ++(runC->npass_);
    ++(lumiC->npass_);
    iEvent.put(std::make_unique<bool>(false));

    if (taggedMode_)
      return forcedValue_;
    return false;
  }

  for (auto const &err : *errors) {
    if (!modulesToWatch_.empty() && (modulesToWatch_.count(err.module) == 0))
      continue;
    if (!categoriesToWatch_.empty() && (categoriesToWatch_.count(err.category) == 0))
      continue;
    if (!modulesToIgnore_.empty() && (modulesToIgnore_.count(err.module) != 0))
      continue;
    if (!categoriesToIgnore_.empty() && (categoriesToIgnore_.count(err.category) != 0))
      continue;

    fail = true;

    //synchronize errorCollection_
    auto guard = make_guard(lumiC->collectionGuard_);

    std::pair<ErrorSet::iterator, bool> result = lumiC->errorCollection_.insert(err);
    if (!result.second) {  // already there
      // need the const_cast as set elements are const
      const_cast<unsigned int &>(result.first->count) += err.count;
      if (result.first->count < maxSavedEventsPerLumi_)
        save = true;
    } else {
      save = true;
    }
  }
  if (save && veryVerbose_) {
    std::cout << "\n === REPORT FOR EVENT " << iEvent.id().event() << " RUN " << iEvent.run() << " LUMI "
              << iEvent.luminosityBlock() << " === " << std::endl;
    print(*errors);
  }

  if (fail) {
    ++(lumiC->nfail_);
    ++(runC->nfail_);
  } else {
    ++(runC->npass_);
    ++(lumiC->npass_);
  }
  iEvent.put(std::make_unique<bool>(fail));  // fail is the unbiased boolean

  if (taggedMode_)
    return forcedValue_;
  return save;
}

template <typename Collection>
void LogErrorEventFilter::increment(ErrorSet &scoreboard, Collection &list) {
  for (auto const &err : list) {
    std::pair<ErrorSet::iterator, bool> result = scoreboard.insert(err);
    // need the const_cast as set elements are const
    if (!result.second)
      const_cast<unsigned int &>(result.first->count) += err.count;
  }
}

template <typename Collection>
void LogErrorEventFilter::print(const Collection &errors) {
  using namespace std;
  cout << setw(40) << left << "Category"
       << " " << setw(60) << left << "Module"
       << " " << setw(10) << left << "Level"
       << " " << setw(9) << right << "Count"
       << "\n";
  cout << setw(40) << left << "----------------------------------------"
       << " " << setw(60) << left << "------------------------------------------------------------"
       << " " << setw(10) << left << "----------"
       << " " << setw(9) << right << "---------"
       << "\n";
  for (auto const &err : errors) {
    cout << setw(40) << left << err.category << " " << setw(60) << left << err.module << " " << setw(10) << left
         << err.severity.getName() << " " << setw(9) << right << err.count << "\n";
  }
  cout << flush;
}

#include "FWCore/Framework/interface/MakerMacros.h"
DEFINE_FWK_MODULE(LogErrorEventFilter);