#include <cppunit/extensions/HelperMacros.h>
#include <ext/alloc_traits.h>
#include <regex.h>
#include <algorithm>
#include <iostream>
#include <iterator>
#include <map>
#include <memory>
#include <string>
#include <utility>
#include <vector>

#include "DetectorDescription/Core/interface/Singleton.h"
#include "DetectorDescription/Core/interface/DDLogicalPart.h"
#include "DetectorDescription/Core/interface/DDName.h"
#include "FWCore/ParameterSet/interface/FileInPath.h"
#include "cppunit/TestAssert.h"
#include "cppunit/TestFixture.h"

namespace {

  std::pair<bool, std::string> oldDDIsValid(const std::string& ns,
                                            const std::string& nm,
                                            std::vector<DDLogicalPart>& result,
                                            bool doRegex) {
    //return std::make_pair(true,"");
    std::string status, aName, aNs;
    bool emptyNs = false;
    if (ns.empty())
      emptyNs = true;

    aName = "^" + nm + "$";
    aNs = "^" + ns + "$";
    //bool flag(true);
    regex_t aRegex, aNsRegex;
    const char* aRegexCStr = aName.c_str();
    const char* aNsRegexCStr = aNs.c_str();
    if (doRegex) {
      //    std:: cout << "Regex " << nm << " " << ns << std::endl;
      if (regcomp(&aRegex, aRegexCStr, 0)) {
        regfree(&aRegex);
        return std::make_pair(false, "Error in the regexp for the name: " + nm);
      }

      if (regcomp(&aNsRegex, aNsRegexCStr, 0)) {
        regfree(&aRegex);
        regfree(&aNsRegex);
        return std::make_pair(false, "Error in the regexp for the namespace: " + ns);
      }
    } else {
      DDName ddnm(nm, ns);
      result.emplace_back(DDLogicalPart(ddnm));
      return std::make_pair(true, "");
    }
    //edm::LogInfo("DDLogicalPart") << " . emptyNs=" << emptyNs << std::endl;
    //edm::LogInfo("DDLogicalPart") << " . qname=[" << ns << ":" << nm << "]" << std::endl;

    // THIS IS THE SLOW PART: I have to compare every namespace & name of every
    // logical part with a regex-comparison .... a linear search always through the
    // full range of logical parts!!!!
    /*
      Algorithm description:
      x. empty nm and ns argument of method means: use all matching regex ^.*$
      a. iterate over all logical part names, match against regex for names
      b. iterate over all namespaces of names found in a & match against regex for namespaces   
    */
    LPNAMES::value_type::const_iterator it(LPNAMES::instance().begin()), ed(LPNAMES::instance().end());
    for (; it != ed; ++it) {
      bool doit = false;
      doit = !regexec(&aRegex, it->first.c_str(), 0, nullptr, 0);
      //if (doit)  edm::LogInfo("DDLogicalPart") << "rgx: " << aName << ' ' << it->first << ' ' << doit << std::endl;
      if (doit) {
        std::vector<DDName>::size_type sz = it->second.size();  // no of 'compatible' namespaces
        if (emptyNs && (sz == 1)) {                             // accept all logical parts in all the namespaces
          result.emplace_back(it->second[0]);
          //std::vector<DDName>::const_iterator nsIt(it->second.begin()), nsEd(it->second.end());
          //for(; nsIt != nsEd; ++nsIt) {
          //   result.emplace_back(DDLogicalPart(*nsIt));
          //   edm::LogInfo("DDLogicalPart") << "DDD-WARNING: multiple namespaces match (in SpecPars PartSelector): " << *nsIt << std::endl;
          //}
        } else if (!emptyNs) {  // only accept matching namespaces
          std::vector<DDName>::const_iterator nsit(it->second.begin()), nsed(it->second.end());
          for (; nsit != nsed; ++nsit) {
            //edm::LogInfo("DDLogicalPart") << "comparing " << aNs << " with " << *nsit << std::endl;
            bool another_doit = !regexec(&aNsRegex, nsit->ns().c_str(), 0, nullptr, 0);
            if (another_doit) {
              //temp.emplace_back(std::make_pair(it->first,*nsit));
              result.emplace_back(DDLogicalPart(*nsit));
            }
          }
        } else {  // emtpyNs and sz>1 -> error, too ambigous
          std::string message = "DDLogicalPart-name \"" + it->first + "\" matching regex \"" + nm +
                                "\" has been found at least in following namespaces:\n";
          std::vector<DDName>::const_iterator vit = it->second.begin();
          for (; vit != it->second.end(); ++vit) {
            message += vit->ns();
            message += " ";
          }
          message += "\nQualify the name with a regexp for the namespace, i.e \".*:name-regexp\" !";

          regfree(&aRegex);
          regfree(&aNsRegex);

          return std::make_pair(false, message);
        }
      }
    }
    bool flag = true;
    std::string message;

    // check whether the found logical-parts are also defined (i.e. have material, solid ...)
    // std::cout << "IsValid-Result " << nm << " :";
    if (!result.empty()) {
      std::vector<DDLogicalPart>::const_iterator lpit(result.begin()), lped(result.end());
      for (; lpit != lped; ++lpit) {
        // std::cout << " " << std::string(lpit->name());
        if (!lpit->isDefined().second) {
          message = message + "LogicalPart " + lpit->name().fullname() + " not (yet) defined!\n";
          flag = false;
        }
      }
    } else {
      flag = false;
      message = "No regex-match for namespace=" + ns + "  name=" + nm + "\n";
    }
    regfree(&aRegex);
    regfree(&aNsRegex);
    // std::cout << std::endl;

    return std::make_pair(flag, message);
  }
}  // namespace

namespace {
  // the static dumper
  // to be used in the real application
  struct BHA {
    ~BHA() {
      LPNAMES::value_type::const_iterator it(LPNAMES::instance().begin()), ed(LPNAMES::instance().end());
      std::cout << "LPNAMES begin" << std::endl;
      for (; it != ed; ++it) {
        std::cout << it->first;
        std::vector<DDName>::const_iterator nsit(it->second.begin()), nsed(it->second.end());
        for (; nsit != nsed; ++nsit)
          std::cout << " " << nsit->ns();
        std::cout << std::endl;
      }
      std::cout << "LPNAMES end" << std::endl;
    }
  };
  //  BHA bah;
}  // namespace

class testDDIsValid : public CppUnit::TestFixture {
  CPPUNIT_TEST_SUITE(testDDIsValid);
  CPPUNIT_TEST(checkAgaistOld);
  CPPUNIT_TEST_SUITE_END();

public:
  void setUp() override {}
  void tearDown() override {}
  void buildIt();
  void testloading();
  void checkAgaistOld();
};

CPPUNIT_TEST_SUITE_REGISTRATION(testDDIsValid);

void testDDIsValid::testloading() {
  std::cerr << "test Loading" << std::endl;
  // get name using FileInPath.
  edm::FileInPath fp("DetectorDescription/Core/test/lpnames.out");
  // test that we load LPNAMES correclty
  //  std::ifstream in("lpnames.out");
  std::ifstream in(fp.fullPath().c_str());
  //  std::cout << "FILE : " << fp << " absolute path " << fp.fullPath().c_str() << std::endl;
  in.unsetf(std::ios::skipws);
  std::istream_iterator<char> sbegin(in), send;
  std::string str;
  std::copy(sbegin, send, std::inserter(str, str.begin()));

  std::ostringstream os;

  LPNAMES::value_type::const_iterator it(LPNAMES::instance().begin()), ed(LPNAMES::instance().end());
  for (; it != ed; ++it) {
    os << it->first;
    std::vector<DDName>::const_iterator nsit(it->second.begin()), nsed(it->second.end());
    for (; nsit != nsed; ++nsit)
      os << " " << nsit->ns();
    os << std::endl;
  }

  if (os.str() != str)
    std::cerr << "not the same!" << std::endl;
  CPPUNIT_ASSERT(os.str() == str);
}

void testDDIsValid::buildIt() {
  // get name using FileInPath.
  edm::FileInPath fp("DetectorDescription/Core/test/lpnames.out");
  // fill LPNAMES
  //  std::ifstream in("lpnames.out");
  std::ifstream in(fp.fullPath().c_str());
  std::string line;
  while (std::getline(in, line)) {
    std::string::size_type p;
    p = line.find(" ");
    std::string nm(line, 0, p);
    std::vector<DDName>& v = LPNAMES::instance()[nm];
    while (p != std::string::npos) {
      ++p;
      std::string::size_type e = line.find(" ", p);
      std::string::size_type s = e - p;
      if (e == std::string::npos)
        s = e;
      v.emplace_back(DDName(nm, line.substr(p, s)));
      p = e;
    }
  }
  std::cerr << "read " << LPNAMES::instance().size() << std::endl;
  CPPUNIT_ASSERT(LPNAMES::instance().size() == 3819);
}

void testDDIsValid::checkAgaistOld() {
  buildIt();
  testloading();
  // get name using FileInPath.
  edm::FileInPath fp("DetectorDescription/Core/test/regex.queries");

  //  std::ifstream in("regex.queries");
  std::ifstream in(fp.fullPath().c_str());

  std::string line;
  const std::string ns;
  int bad = 0;
  while (std::getline(in, line)) {
    std::string::size_type p = line.find(" ");
    ++p;
    std::string::size_type e = line.find(" ", p);
    // ns, we know, is always ""
    std::vector<DDLogicalPart> oldResult;
    std::vector<DDLogicalPart> result;
    std::pair<bool, std::string> oldRes = oldDDIsValid(ns, line.substr(p, e - p), oldResult, true);
    std::pair<bool, std::string> res = DDIsValid(ns, line.substr(p, e - p), result, true);
    if (oldRes.first != res.first || oldRes.second != res.second || oldResult.size() != result.size()) {
      ++bad;
      continue;
    }
    for (int i = 0; i != int(result.size()); ++i) {
      if (result[i].name() == oldResult[i].name())
        continue;
      ++bad;
      break;
    }
  }

  if (bad)
    std::cerr << bad << " queries not the same!" << std::endl;
  CPPUNIT_ASSERT(bad == 0);
}