#ifndef ALGORITHMMPITEST_H_
#define ALGORITHMMPITEST_H_

#include <cxxtest/TestSuite.h>

#include "MantidAPI/Algorithm.h"
#include "MantidAPI/HistogramValidator.h"
#include "MantidKernel/CompositeValidator.h"
#include "MantidAPI/AnalysisDataService.h"

#include "MantidKernel/Property.h"
#include "MantidAPI/AlgorithmFactory.h"
#include "MantidTestHelpers/FakeObjects.h"
#include "MantidAPI/WorkspaceProperty.h"
#include "MantidAPI/FrameworkManager.h"
#ifdef MPI_EXPERIMENTAL
#include "MantidParallel/ParallelRunner.h"
#endif

using namespace Mantid::Kernel;
using namespace Mantid::API;

class FakeWorkspaceA : public WorkspaceTester {
public:
  using WorkspaceTester::WorkspaceTester;
  const std::string id() const override { return "FakeWorkspaceA"; }

private:
  FakeWorkspaceA *doClone() const override { return new FakeWorkspaceA(*this); }
  FakeWorkspaceA *doCloneEmpty() const override {
    return new FakeWorkspaceA(storageMode());
  }
};

class FakeWorkspaceB : public WorkspaceTester {
public:
  using WorkspaceTester::WorkspaceTester;
  const std::string id() const override { return "FakeWorkspaceB"; }

private:
  FakeWorkspaceB *doClone() const override { return new FakeWorkspaceB(*this); }
  FakeWorkspaceB *doCloneEmpty() const override {
    return new FakeWorkspaceB(storageMode());
  }
};

class NoParallelismAlgorithm : public Algorithm {
public:
  const std::string name() const override { return "NoParallelismAlgorithm"; }
  int version() const override { return 1; }
  const std::string category() const override { return ""; }
  const std::string summary() const override { return ""; }

  void init() override {
    declareProperty(make_unique<WorkspaceProperty<>>("InputWorkspace", "",
                                                     Direction::Input));
  }

  void exec() override {}
};

class AlgorithmWithBad_getParallelExecutionMode : public Algorithm {
public:
  const std::string name() const override {
    return "AlgorithmWithBad_getParallelExecutionMode ";
  }
  int version() const override { return 1; }
  const std::string category() const override { return ""; }
  const std::string summary() const override { return ""; }
  void init() override {}
  void exec() override {}

protected:
  Parallel::ExecutionMode getParallelExecutionMode(
      const std::map<std::string, Parallel::StorageMode> &storageModes)
      const override {
    static_cast<void>(storageModes);
    return Parallel::ExecutionMode::Serial;
  }
};

class FakeAlg1To1 : public Algorithm {
public:
  const std::string name() const override { return "FakeAlg1To1"; }
  int version() const override { return 1; }
  const std::string category() const override { return ""; }
  const std::string summary() const override { return ""; }
  void init() override {
    declareProperty(Kernel::make_unique<WorkspaceProperty<>>(
        "InputWorkspace", "", Kernel::Direction::Input,
        Kernel::make_unique<HistogramValidator>()));
    declareProperty(make_unique<WorkspaceProperty<Workspace>>(
        "OutputWorkspace", "", Direction::Output));
  }
  void exec() override {
    boost::shared_ptr<MatrixWorkspace> ws = getProperty("InputWorkspace");
    setProperty("OutputWorkspace", ws->clone());
  }

protected:
  Parallel::ExecutionMode getParallelExecutionMode(
      const std::map<std::string, Parallel::StorageMode> &storageModes)
      const override {
    return getCorrespondingExecutionMode(storageModes.at("InputWorkspace"));
  }
};

class FakeAlgNTo0 : public Algorithm {
public:
  const std::string name() const override { return "FakeAlgNTo0"; }
  int version() const override { return 1; }
  const std::string category() const override { return ""; }
  const std::string summary() const override { return ""; }
  void init() override {
    declareProperty(Kernel::make_unique<WorkspaceProperty<>>(
        "InputWorkspace1", "", Kernel::Direction::Input,
        Kernel::make_unique<HistogramValidator>()));
    declareProperty(Kernel::make_unique<WorkspaceProperty<>>(
        "InputWorkspace2", "", Kernel::Direction::Input,
        Kernel::make_unique<HistogramValidator>()));
  }
  void exec() override {
    boost::shared_ptr<MatrixWorkspace> ws1 = getProperty("InputWorkspace1");
    boost::shared_ptr<MatrixWorkspace> ws2 = getProperty("InputWorkspace2");
  }

protected:
  Parallel::ExecutionMode getParallelExecutionMode(
      const std::map<std::string, Parallel::StorageMode> &storageModes)
      const override {
    return getCorrespondingExecutionMode(storageModes.at("InputWorkspace1"));
  }
};

class FakeAlgNTo1StorageModeFailure : public Algorithm {
public:
  const std::string name() const override {
    return "FakeAlgNTo1StorageModeFailure";
  }
  int version() const override { return 1; }
  const std::string category() const override { return ""; }
  const std::string summary() const override { return ""; }
  void init() override {
    declareProperty(Kernel::make_unique<WorkspaceProperty<>>(
        "InputWorkspace1", "", Kernel::Direction::Input,
        Kernel::make_unique<HistogramValidator>()));
    declareProperty(Kernel::make_unique<WorkspaceProperty<>>(
        "InputWorkspace2", "", Kernel::Direction::Input,
        Kernel::make_unique<HistogramValidator>()));
    declareProperty(make_unique<WorkspaceProperty<Workspace>>(
        "OutputWorkspace", "", Direction::Output));
  }
  void exec() override {
    boost::shared_ptr<MatrixWorkspace> ws1 = getProperty("InputWorkspace1");
    boost::shared_ptr<MatrixWorkspace> ws2 = getProperty("InputWorkspace2");
    setProperty("OutputWorkspace", ws1->clone());
  }

protected:
  Parallel::ExecutionMode getParallelExecutionMode(
      const std::map<std::string, Parallel::StorageMode> &storageModes)
      const override {
    return getCorrespondingExecutionMode(storageModes.at("InputWorkspace1"));
  }
};

class FakeAlgNTo1 : public FakeAlgNTo1StorageModeFailure {
public:
  const std::string name() const override { return "FakeAlgNTo1"; }

protected:
  void execNonMaster() override {
    // Default implementation only works for 1:1 input->output, so we have to
    // provide an alternative implementation here.
    boost::shared_ptr<MatrixWorkspace> ws1 = getProperty("InputWorkspace1");
    setProperty("OutputWorkspace", ws1->cloneEmpty());
  }
};

template <Parallel::StorageMode storageMode>
class FakeAlg0To1 : public Algorithm {
public:
  const std::string name() const override {
    return "FakeAlg0To1" + Parallel::toString(storageMode);
  }
  int version() const override { return 1; }
  const std::string category() const override { return ""; }
  const std::string summary() const override { return ""; }
  void init() override {
    declareProperty(make_unique<WorkspaceProperty<Workspace>>(
        "OutputWorkspace", "", Direction::Output));
  }
  void exec() override {
    auto ws = Kernel::make_unique<FakeWorkspaceA>(storageMode);
    ws->initialize(1, 2, 1);
    setProperty("OutputWorkspace", std::move(ws));
  }

protected:
  void execNonMaster() override {
    // This method should never create anything that is not
    // StorageMode::MasterOnly.
    setProperty("OutputWorkspace", Kernel::make_unique<FakeWorkspaceA>(
                                       Parallel::StorageMode::MasterOnly));
  }
  Parallel::ExecutionMode getParallelExecutionMode(
      const std::map<std::string, Parallel::StorageMode> &storageModes)
      const override {
    static_cast<void>(storageModes);
    return getCorrespondingExecutionMode(storageMode);
  }
};

template <Parallel::StorageMode storageModeOut>
class FakeAlg1To1StorageModeTransition : public Algorithm {
public:
  const std::string name() const override {
    return "FakeAlgAnyModeTo" + Parallel::toString(storageModeOut);
  }
  int version() const override { return 1; }
  const std::string category() const override { return ""; }
  const std::string summary() const override { return ""; }
  void init() override {
    declareProperty(Kernel::make_unique<WorkspaceProperty<>>(
        "InputWorkspace", "", Kernel::Direction::Input,
        Kernel::make_unique<HistogramValidator>()));
    declareProperty(make_unique<WorkspaceProperty<Workspace>>(
        "OutputWorkspace", "", Direction::Output));
  }
  void exec() override {
    boost::shared_ptr<MatrixWorkspace> ws = getProperty("InputWorkspace");
    setProperty("OutputWorkspace",
                Kernel::make_unique<FakeWorkspaceA>(storageModeOut));
  }

protected:
  void execNonMaster() override {
    // This method should never create anything that is not
    // StorageMode::MasterOnly.
    setProperty("OutputWorkspace", Kernel::make_unique<FakeWorkspaceA>(
                                       Parallel::StorageMode::MasterOnly));
  }
  Parallel::ExecutionMode getParallelExecutionMode(
      const std::map<std::string, Parallel::StorageMode> &storageModes)
      const override {
    static_cast<void>(storageModes);
    // ExecutionMode depends on *output* StorageMode.
    return getCorrespondingExecutionMode(storageModeOut);
  }
};

void run_NoParallelismAlgorithm(const Parallel::Communicator &comm) {
  for (auto storageMode :
       {Parallel::StorageMode::Cloned, Parallel::StorageMode::Distributed,
        Parallel::StorageMode::MasterOnly}) {
    NoParallelismAlgorithm alg;
    alg.setCommunicator(comm);
    auto in = boost::make_shared<WorkspaceTester>(storageMode);
    alg.initialize();
    alg.setProperty("InputWorkspace", in);
    if (comm.size() == 1) {
      TS_ASSERT_THROWS_NOTHING(alg.execute());
      TS_ASSERT(alg.isExecuted());
    } else {
      TS_ASSERT_THROWS_EQUALS(
          alg.execute(), const std::runtime_error &e, std::string(e.what()),
          "Algorithm does not support execution with input workspaces of the "
          "following storage types: \nInputWorkspace " +
              Parallel::toString(storageMode) + "\n.");
    }
  }
}

void run_AlgorithmWithBad_getParallelExecutionMode(
    const Parallel::Communicator &comm) {
  AlgorithmWithBad_getParallelExecutionMode alg;
  alg.setCommunicator(comm);
  alg.initialize();
  if (comm.size() == 1) {
    TS_ASSERT_THROWS_NOTHING(alg.execute());
  } else {
    TS_ASSERT_THROWS_EQUALS(alg.execute(), const std::runtime_error &e,
                            std::string(e.what()),
                            "Parallel::ExecutionMode::Serial is not a valid "
                            "*parallel* execution mode.");
  }
}

void run1To1(const Parallel::Communicator &comm) {
  for (auto storageMode :
       {Parallel::StorageMode::Cloned, Parallel::StorageMode::Distributed,
        Parallel::StorageMode::MasterOnly}) {
    FakeAlg1To1 alg;
    alg.setCommunicator(comm);
    alg.initialize();
    auto in = boost::make_shared<FakeWorkspaceA>(storageMode);
    in->initialize(1, 2, 1);
    if (storageMode != Parallel::StorageMode::MasterOnly || comm.rank() == 0) {
      alg.setProperty("InputWorkspace", in);
    } else {
      alg.setProperty("InputWorkspace", in->cloneEmpty());
    }
    // In a true MPI run we could simply use "out", but in the threaded
    // fake-runner we have only one ADS, so we have to avoid clashes.
    std::string outName("out" + std::to_string(comm.rank()));
    alg.setProperty("OutputWorkspace", outName);
    TS_ASSERT_THROWS_NOTHING(alg.execute());
    auto out = AnalysisDataService::Instance().retrieve(outName);
    TS_ASSERT_EQUALS(out->storageMode(), storageMode);
    TS_ASSERT_EQUALS(out->id(), "FakeWorkspaceA");
  }
}

void runNTo0(const Parallel::Communicator &comm) {
  for (auto storageMode :
       {Parallel::StorageMode::Cloned, Parallel::StorageMode::Distributed,
        Parallel::StorageMode::MasterOnly}) {
    FakeAlgNTo0 alg;
    alg.setCommunicator(comm);
    alg.initialize();
    auto in1 = boost::make_shared<FakeWorkspaceA>(storageMode);
    auto in2 = boost::make_shared<FakeWorkspaceB>(storageMode);
    in1->initialize(1, 2, 1);
    in2->initialize(1, 2, 1);
    if (storageMode != Parallel::StorageMode::MasterOnly || comm.rank() == 0) {
      alg.setProperty("InputWorkspace1", in1);
      alg.setProperty("InputWorkspace2", in2);
    } else {
      alg.setProperty("InputWorkspace1", in1->cloneEmpty());
      alg.setProperty("InputWorkspace2", in2->cloneEmpty());
    }
    TS_ASSERT_THROWS_NOTHING(alg.execute());
  }
}

void runNTo1StorageModeFailure(const Parallel::Communicator &comm) {
  for (auto storageMode :
       {Parallel::StorageMode::Cloned, Parallel::StorageMode::Distributed,
        Parallel::StorageMode::MasterOnly}) {
    FakeAlgNTo1StorageModeFailure alg;
    alg.setCommunicator(comm);
    alg.initialize();
    auto in1 = boost::make_shared<FakeWorkspaceA>(storageMode);
    auto in2 = boost::make_shared<FakeWorkspaceB>(storageMode);
    in1->initialize(1, 2, 1);
    in2->initialize(1, 2, 1);
    if (storageMode != Parallel::StorageMode::MasterOnly || comm.rank() == 0) {
      alg.setProperty("InputWorkspace1", in1);
      alg.setProperty("InputWorkspace2", in2);
    } else {
      alg.setProperty("InputWorkspace1", in1->cloneEmpty());
      alg.setProperty("InputWorkspace2", in2->cloneEmpty());
    }
    // In a true MPI run we could simply use "out", but in the threaded
    // fake-runner we have only one ADS, so we have to avoid clashes.
    std::string outName("out" + std::to_string(comm.rank()));
    alg.setProperty("OutputWorkspace", outName);
    if (storageMode != Parallel::StorageMode::MasterOnly || comm.rank() == 0) {
      TS_ASSERT_THROWS_NOTHING(alg.execute());
      TS_ASSERT(alg.isExecuted());
      auto out = AnalysisDataService::Instance().retrieve(outName);
      // Preserving storage mode is actually not guaranteed, but this
      // implementation does of FakeAlgNTo1StorageModeFailure does.
      TS_ASSERT_EQUALS(out->storageMode(), storageMode);
      TS_ASSERT_EQUALS(out->id(), "FakeWorkspaceA");
    } else {
      // Internally this actually does throw but exceptions are just logged.
      TS_ASSERT_THROWS_NOTHING(alg.execute());
      TS_ASSERT(!alg.isExecuted());
    }
  }
}

void runNTo1(const Parallel::Communicator &comm) {
  for (auto storageMode :
       {Parallel::StorageMode::Cloned, Parallel::StorageMode::Distributed,
        Parallel::StorageMode::MasterOnly}) {
    FakeAlgNTo1 alg;
    alg.setCommunicator(comm);
    alg.initialize();
    auto in1 = boost::make_shared<FakeWorkspaceA>(storageMode);
    auto in2 = boost::make_shared<FakeWorkspaceB>(storageMode);
    in1->initialize(1, 2, 1);
    in2->initialize(1, 2, 1);
    if (storageMode != Parallel::StorageMode::MasterOnly || comm.rank() == 0) {
      alg.setProperty("InputWorkspace1", in1);
      alg.setProperty("InputWorkspace2", in2);
    } else {
      alg.setProperty("InputWorkspace1", in1->cloneEmpty());
      alg.setProperty("InputWorkspace2", in2->cloneEmpty());
    }
    // In a true MPI run we could simply use "out", but in the threaded
    // fake-runner we have only one ADS, so we have to avoid clashes.
    std::string outName("out" + std::to_string(comm.rank()));
    alg.setProperty("OutputWorkspace", outName);
    TS_ASSERT_THROWS_NOTHING(alg.execute());
    TS_ASSERT(alg.isExecuted());
    auto out = AnalysisDataService::Instance().retrieve(outName);
    TS_ASSERT_EQUALS(out->storageMode(), storageMode);
    TS_ASSERT_EQUALS(out->id(), "FakeWorkspaceA");
  }
}

template <Parallel::StorageMode storageMode>
void run0To1(const Parallel::Communicator &comm) {
  FakeAlg0To1<storageMode> alg;
  alg.setCommunicator(comm);
  alg.initialize();
  // In a true MPI run we could simply use "out", but in the threaded
  // fake-runner we have only one ADS, so we have to avoid clashes.
  std::string outName("out" + std::to_string(comm.rank()));
  alg.setProperty("OutputWorkspace", outName);
  TS_ASSERT_THROWS_NOTHING(alg.execute());
  TS_ASSERT(alg.isExecuted());
  auto out = AnalysisDataService::Instance().retrieve(outName);
  TS_ASSERT_EQUALS(out->storageMode(), storageMode);
  TS_ASSERT_EQUALS(out->id(), "FakeWorkspaceA");
}

template <Parallel::StorageMode modeIn, Parallel::StorageMode modeOut>
void run1To1StorageModeTransition(const Parallel::Communicator &comm) {
  FakeAlg1To1StorageModeTransition<modeOut> alg;
  alg.setCommunicator(comm);
  alg.initialize();
  auto in = boost::make_shared<FakeWorkspaceA>(modeIn);
  in->initialize(1, 2, 1);
  if (modeIn != Parallel::StorageMode::MasterOnly || comm.rank() == 0) {
    alg.setProperty("InputWorkspace", in);
  } else {
    alg.setProperty("InputWorkspace", in->cloneEmpty());
  }
  // In a true MPI run we could simply use "out", but in the threaded
  // fake-runner we have only one ADS, so we have to avoid clashes.
  std::string outName("out" + std::to_string(comm.rank()));
  alg.setProperty("OutputWorkspace", outName);
  TS_ASSERT_THROWS_NOTHING(alg.execute());
  TS_ASSERT(alg.isExecuted());
  auto out = AnalysisDataService::Instance().retrieve(outName);
  TS_ASSERT_EQUALS(out->storageMode(), modeOut);
  TS_ASSERT_EQUALS(out->id(), "FakeWorkspaceA");
}

void runChained(const Parallel::Communicator &comm) {
  using Parallel::StorageMode;
  FakeAlg0To1<StorageMode::MasterOnly> alg1;
  alg1.initialize();
  std::string outName("out" + std::to_string(comm.rank()));
  alg1.setProperty("OutputWorkspace", outName);
  TS_ASSERT_THROWS_NOTHING(alg1.execute());
  TS_ASSERT(alg1.isExecuted());
  auto ws1 = AnalysisDataService::Instance().retrieve(outName);
  TS_ASSERT_EQUALS(ws1->storageMode(), StorageMode::MasterOnly);

  FakeAlg1To1StorageModeTransition<StorageMode::Distributed> alg2;
  alg2.setCommunicator(comm);
  alg2.initialize();
  alg2.setProperty("InputWorkspace", ws1);
  alg2.setProperty("OutputWorkspace", outName);
  TS_ASSERT_THROWS_NOTHING(alg2.execute());
  TS_ASSERT(alg2.isExecuted());
  auto ws2 = AnalysisDataService::Instance().retrieve(outName);
  TS_ASSERT_EQUALS(ws2->storageMode(), StorageMode::Distributed);
}

class AlgorithmMPITest : public CxxTest::TestSuite {
public:
  // This pair of boilerplate methods prevent the suite being created statically
  // This means the constructor isn't called when running other tests
  static AlgorithmMPITest *createSuite() { return new AlgorithmMPITest(); }
  static void destroySuite(AlgorithmMPITest *suite) { delete suite; }

  AlgorithmMPITest() {
    Mantid::API::FrameworkManager::Instance();
    AnalysisDataService::Instance();
  }

  void testNoParallelismAlgorithm() {
    run_NoParallelismAlgorithm(Parallel::Communicator{});
#ifdef MPI_EXPERIMENTAL
    runParallel(run_NoParallelismAlgorithm);
#endif
    Mantid::API::AnalysisDataService::Instance().clear();
  }

  void testAlgorithmWithBad_getParallelExecutionMode() {
    run_AlgorithmWithBad_getParallelExecutionMode(Parallel::Communicator{});
#ifdef MPI_EXPERIMENTAL
    runParallel(run_AlgorithmWithBad_getParallelExecutionMode);
#endif
    Mantid::API::AnalysisDataService::Instance().clear();
  }

  void test1To1() {
    run1To1(Parallel::Communicator{});
#ifdef MPI_EXPERIMENTAL
    runParallel(run1To1);
#endif
    Mantid::API::AnalysisDataService::Instance().clear();
  }

  void testNTo0() {
    runNTo0(Parallel::Communicator{});
#ifdef MPI_EXPERIMENTAL
    runParallel(runNTo0);
#endif
    Mantid::API::AnalysisDataService::Instance().clear();
  }

  void testNTo1StorageModeFailure() {
    runNTo1StorageModeFailure(Parallel::Communicator{});
#ifdef MPI_EXPERIMENTAL
    runParallel(runNTo1StorageModeFailure);
#endif
    Mantid::API::AnalysisDataService::Instance().clear();
  }

  void testNTo1() {
    runNTo1(Parallel::Communicator{});
#ifdef MPI_EXPERIMENTAL
    runParallel(runNTo1);
#endif
    Mantid::API::AnalysisDataService::Instance().clear();
  }

  void test0To1() {
    run0To1<Parallel::StorageMode::Cloned>(Parallel::Communicator{});
    run0To1<Parallel::StorageMode::Distributed>(Parallel::Communicator{});
    run0To1<Parallel::StorageMode::MasterOnly>(Parallel::Communicator{});
#ifdef MPI_EXPERIMENTAL
    runParallel(run0To1<Parallel::StorageMode::Cloned>);
    runParallel(run0To1<Parallel::StorageMode::Distributed>);
    runParallel(run0To1<Parallel::StorageMode::MasterOnly>);
#endif
    Mantid::API::AnalysisDataService::Instance().clear();
  }

  void test1To1StorageModeTransition() {
    using Parallel::StorageMode;
    run1To1StorageModeTransition<StorageMode::Cloned, StorageMode::Cloned>(
        Parallel::Communicator{});
    run1To1StorageModeTransition<StorageMode::Cloned, StorageMode::Distributed>(
        Parallel::Communicator{});
    run1To1StorageModeTransition<StorageMode::Cloned, StorageMode::MasterOnly>(
        Parallel::Communicator{});
    run1To1StorageModeTransition<StorageMode::Distributed, StorageMode::Cloned>(
        Parallel::Communicator{});
    run1To1StorageModeTransition<StorageMode::Distributed,
                                 StorageMode::Distributed>(
        Parallel::Communicator{});
    run1To1StorageModeTransition<StorageMode::Distributed,
                                 StorageMode::MasterOnly>(
        Parallel::Communicator{});
    run1To1StorageModeTransition<StorageMode::MasterOnly, StorageMode::Cloned>(
        Parallel::Communicator{});
    run1To1StorageModeTransition<StorageMode::MasterOnly,
                                 StorageMode::Distributed>(
        Parallel::Communicator{});
    run1To1StorageModeTransition<StorageMode::MasterOnly,
                                 StorageMode::MasterOnly>(
        Parallel::Communicator{});
#ifdef MPI_EXPERIMENTAL
    runParallel(
        run1To1StorageModeTransition<StorageMode::Cloned, StorageMode::Cloned>);
    runParallel(run1To1StorageModeTransition<StorageMode::Cloned,
                                             StorageMode::Distributed>);
    runParallel(run1To1StorageModeTransition<StorageMode::Cloned,
                                             StorageMode::MasterOnly>);
    runParallel(run1To1StorageModeTransition<StorageMode::Distributed,
                                             StorageMode::Cloned>);
    runParallel(run1To1StorageModeTransition<StorageMode::Distributed,
                                             StorageMode::Distributed>);
    runParallel(run1To1StorageModeTransition<StorageMode::Distributed,
                                             StorageMode::MasterOnly>);
    runParallel(run1To1StorageModeTransition<StorageMode::MasterOnly,
                                             StorageMode::Cloned>);
    runParallel(run1To1StorageModeTransition<StorageMode::MasterOnly,
                                             StorageMode::Distributed>);
    runParallel(run1To1StorageModeTransition<StorageMode::MasterOnly,
                                             StorageMode::MasterOnly>);
#endif
    Mantid::API::AnalysisDataService::Instance().clear();
  }

  void testChained() {
    // Test that output from one algorithm can be fed into another (in
    // combination with non-trivial storage modes).
    runChained(Parallel::Communicator{});
#ifdef MPI_EXPERIMENTAL
    runParallel(runChained);
#endif
    Mantid::API::AnalysisDataService::Instance().clear();
  }
};

#endif /*ALGORITHMMPITEST_H_*/