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/*!\internal
 * \file
 * \brief
 * Tests for gmx::SetAtoms
 *
 * \author Paul Bauer <paul.bauer.q@gmail.com>
 * \ingroup module_coordinateio
 */


#include "gmxpre.h"

#include "gromacs/coordinateio/outputadapters/setatoms.h"

#include <utility>

#include "gromacs/coordinateio/tests/coordinate_test.h"
#include "gromacs/fileio/trxio.h"
#include "gromacs/trajectory/trajectoryframe.h"
#include "gromacs/trajectoryanalysis/topologyinformation.h"

#include "testutils/testfilemanager.h"

namespace gmx
{

namespace test
{

/*!\brief
 * Test fixture to prepare a setatoms object to pass data through.
 */
class SetAtomsTest : public gmx::test::CommandLineTestBase
{
public:
    //! Prepare test fixture topology to have atoms available.
    SetAtomsTest()
    {
        topology_.fillFromInputFile(TestFileManager::getInputFilePath("lysozyme.pdb").u8string());
    }

    /*! \brief
     * Get access to the method for changing atom information.
     *
     * \param[in] type Type to use for setting up method.
     * \param[in] haveAtomsAvailable Decide if method shouöd have atoms stored or not.
     */
    SetAtoms* setAtoms(ChangeAtomsType type, bool haveAtomsAvailable)
    {
        if (!setAtoms_)
        {
            if (haveAtomsAvailable)
            {
                setAtoms_ = std::make_unique<SetAtoms>(type, topology_.copyAtoms());
            }
            else
            {
                setAtoms_ = std::make_unique<SetAtoms>(type, nullptr);
            }
        }
        return setAtoms_.get();
    }
    //! Get access to a t_atoms struct to use in the dummy t_trxframe.
    t_atoms* getAtomsCopy() { return const_cast<t_atoms*>(topology_.atoms()); }

private:
    //! Object to use for tests
    SetAtomsPointer setAtoms_;
    //! Local topology to get atoms from
    TopologyInformation topology_;
};

TEST_F(SetAtomsTest, RemovesExistingAtoms)
{
    t_trxframe frame;
    clear_trxframe(&frame, true);

    frame.bAtoms = true;
    frame.atoms  = getAtomsCopy();

    EXPECT_NE(frame.atoms, nullptr);

    SetAtoms* method = setAtoms(ChangeAtomsType::Never, true);
    EXPECT_NO_THROW(method->processFrame(0, &frame));

    EXPECT_FALSE(frame.bAtoms);
    EXPECT_EQ(frame.atoms, nullptr);
}

TEST_F(SetAtomsTest, AddsNewAtoms)
{
    t_trxframe frame;
    clear_trxframe(&frame, true);

    frame.bAtoms = false;
    frame.atoms  = nullptr;

    SetAtoms* method = setAtoms(ChangeAtomsType::AlwaysFromStructure, true);
    EXPECT_NO_THROW(method->processFrame(0, &frame));

    EXPECT_TRUE(frame.bAtoms);
    EXPECT_NE(frame.atoms, nullptr);
}

TEST_F(SetAtomsTest, ThrowsOnRequiredAtomsNotAvailable)
{
    t_trxframe frame;
    clear_trxframe(&frame, true);

    frame.bAtoms = false;
    frame.atoms  = nullptr;

    SetAtoms* method = setAtoms(ChangeAtomsType::Always, false);
    EXPECT_THROW(method->processFrame(0, &frame), InconsistentInputError);
}

TEST_F(SetAtomsTest, WillUseOldAtomsWhenNoNewAvailable)
{
    t_trxframe frame;
    clear_trxframe(&frame, true);

    frame.bAtoms = true;
    frame.atoms  = getAtomsCopy();

    EXPECT_NE(frame.atoms, nullptr);

    SetAtoms* method = setAtoms(ChangeAtomsType::Always, false);
    EXPECT_NO_THROW(method->processFrame(0, &frame));
}

TEST_F(SetAtomsTest, ThrowsWhenUserAtomReplacementNotPossible)
{
    t_trxframe frame;
    clear_trxframe(&frame, true);

    frame.bAtoms = true;
    frame.atoms  = getAtomsCopy();

    EXPECT_NE(frame.atoms, nullptr);

    SetAtoms* method = setAtoms(ChangeAtomsType::AlwaysFromStructure, false);
    EXPECT_THROW(method->processFrame(0, &frame), InconsistentInputError);
}

} // namespace test

} // namespace gmx
