// This is the catalog recovery program. For it to be successful, the
// original archive must have been created using the "cat=s" option.

#include <fstream>
#include <iostream>

#include "Alignment/Geners/interface/BinaryArchiveBase.hh"
#include <memory>
#include "Alignment/Geners/interface/CatalogIO.hh"
#include "Alignment/Geners/interface/ContiguousCatalog.hh"
#include "Alignment/Geners/interface/IOException.hh"
#include "Alignment/Geners/interface/streamposIO.hh"

#include "CmdLine.hh"

using namespace gs;
using namespace std;

static void print_usage(const char *progname) {
  cout << "\nUsage: " << progname << " archive_name [annotation]\n\n"
       << "This program recovers the \"geners\" catalog data from binary "
          "archives.\n"
       << "The recovery is possible only if the archive mode string included "
          "the\n"
       << "\"cat=i\" section which instructs the binary archive to write a "
          "duplicate\n"
       << "copy of item metadata into the data stream. This mode of operation\n"
       << "is recommended in the development stage of your project, so that "
          "the\n"
       << "catalog can be recovered even after an unexpected program crash.\n\n"
       << "The first command line argument is the name of the \"geners\" "
          "archive\n"
       << "without extension or data file number. The second argument is "
          "optional.\n"
       << "If provided, it will become the annotation string added to the "
          "recovered\n"
       << "catalog.\n"
       << endl;
}

namespace {
  class CatalogRecovery : public BinaryArchiveBase {
    inline std::ostream &plainOutputStream() { return f_; }

    inline std::istream &plainInputStream(unsigned long long /* id */,
                                          unsigned * /* compressionCode */,
                                          unsigned long long * /* length */) {
      return f_;
    }

    inline void openFile(const unsigned long count) {
      std::ostringstream os;
      os << AbsArchive::name() << '.' << count << ".gsbd";
      const std::string &fname = os.str();
      openDataFile(f_, fname.c_str());
      cout << "Processing file " << fname << "\n";
      cout.flush();
    }

    inline unsigned long long addToCatalog(const AbsRecord & /* record */,
                                           unsigned /* compressCode */,
                                           unsigned long long /* itemLength */) {
      return 0ULL;
    }

    fstream f_;
    ContiguousCatalog cat_;

  public:
    inline CatalogRecovery(const char *name) : BinaryArchiveBase(name, "r") {}

    inline ~CatalogRecovery() {
      if (f_.is_open())
        f_.close();
    }

    inline std::string catalogFileName() const { return AbsArchive::name() + ".gsbmf"; }

    inline unsigned long long processFile(const unsigned long fileNumber) {
      openFile(fileNumber);
      if (!injectMetadata())
        throw IOInvalidData(
            "Item metadata was not written into the data stream. "
            "Catalog can not be recovered.");
      assert(catalogEntryClassId());
      assert(itemLocationClassId());

      const std::streampos zeropos(0);
      unsigned long long count = 0;
      for (f_.peek(); !f_.eof(); f_.peek()) {
        unsigned long long id = 0;
        std::streampos jump(0);
        read_pod(f_, &jump);
        if (f_.fail() || jump == zeropos)
          return count;
        f_.seekp(jump);
        if (f_.fail())
          return count;
        const CatalogEntry *entry = CatalogEntry::read(*catalogEntryClassId(), *itemLocationClassId(), f_);
        if (entry) {
          id =
              cat_.makeEntry(*entry, entry->compressionCode(), entry->itemLength(), entry->location(), entry->offset());
          delete entry;
        }
        if (!id)
          return count;
        ++count;
      }
      return count;
    }

    inline void writeCatalog(const std::vector<std::string> &annotations) {
      const std::string &catFile = catalogFileName();
      ofstream cats(catFile.c_str());
      if (!cats) {
        std::ostringstream os;
        os << "In CatalogRecovery::writeCatalog: "
           << "failed to open catalog data file \"" << catFile << '"';
        throw IOOpeningFailure(os.str());
      }

      const unsigned compress = static_cast<unsigned>(compressionMode());
      if (!writeBinaryCatalog(cats, compress, 1, annotations, cat_)) {
        std::ostringstream os;
        os << "In CatalogRecovery::writeCatalog: "
           << "failed to write catalog data to file " << catFile;
        throw IOWriteFailure(os.str());
      }
    }

    inline void flush() {}
  };
}  // namespace

int main(int argc, char const *argv[]) {
  CmdLine cmdline(argc, argv);

  if (argc == 1) {
    print_usage(cmdline.progname());
    return 0;
  }

  std::string archiveName;
  std::vector<std::string> annotations;
  try {
    cmdline.optend();

    const unsigned cmdargc = cmdline.argc();
    if (cmdargc != 1 && cmdargc != 2)
      throw CmdLineError("wrong number of command line arguments");
    cmdline >> archiveName;
    if (cmdargc > 1) {
      annotations.resize(1);
      cmdline >> annotations[0];
    }
  } catch (CmdLineError &e) {
    cerr << "Error in " << cmdline.progname() << ": " << e.str() << endl;
    print_usage(cmdline.progname());
    return 1;
  }

  CatalogRecovery recovery(archiveName.c_str());

  // Check if the catalog file already exists. Do not overwrite.
  const std::string &catFile = recovery.catalogFileName();
  {
    ifstream cats(catFile.c_str());
    if (cats) {
      cout << "Catalog file \"" << catFile << "\" already exists" << endl;
      return 1;
    }
  }

  unsigned long long itemCount = 0;
  unsigned long fileCount = 0;
  try {
    for (;; ++fileCount)
      itemCount += recovery.processFile(fileCount);
  } catch (IOOpeningFailure &e) {
    if (!fileCount) {
      cout << "Archive \"" << archiveName << "\" could not be open. " << e.what() << endl;
      return 1;
    }
  } catch (exception &e) {
    cout << "Error in data processing cycle. " << e.what() << endl;
    return 1;
  }

  try {
    recovery.writeCatalog(annotations);
  } catch (exception &e) {
    cout << e.what() << endl;
    return 1;
  }

  cout << "Wrote catalog file \"" << catFile << "\"\n"
       << "The catalog contains metadata for " << itemCount << " items found in " << fileCount << " data file"
       << (fileCount == 1UL ? "" : "s") << endl;
  return 0;
}