# type: ignore
from math import cos, sin, pi

import numpy as np

from ase import Atoms
from ase.calculators.tip3p import TIP3P, epsilon0, sigma0, rOH, angleHOH
from ase.calculators.qmmm import SimpleQMMM, EIQMMM, LJInteractions
from ase.calculators.turbomole import Turbomole
from ase.constraints import FixInternals
from ase.optimize import BFGS

def test_turbomole_qmmm():
    """Test the Turbomole calculator in simple QMMM and
    explicit interaction QMMM simulations."""

    r = rOH
    a = angleHOH * pi / 180
    D = np.linspace(2.5, 3.5, 30)

    interaction = LJInteractions({('O', 'O'): (epsilon0, sigma0)})
    qm_par = {'esp fit': 'kollman', 'multiplicity': 1}

    for calc in [
            TIP3P(),
            SimpleQMMM([0, 1, 2], Turbomole(**qm_par), TIP3P(), TIP3P()),
            SimpleQMMM([0, 1, 2], Turbomole(**qm_par), TIP3P(), TIP3P(),
                       vacuum=3.0),
            EIQMMM([0, 1, 2], Turbomole(**qm_par), TIP3P(), interaction),
            EIQMMM([3, 4, 5], Turbomole(**qm_par), TIP3P(), interaction,
                   vacuum=3.0),
            EIQMMM([0, 1, 2], Turbomole(**qm_par), TIP3P(), interaction,
                   vacuum=3.0)]:
        dimer = Atoms('H2OH2O',
                      [(r * cos(a), 0, r * sin(a)),
                       (r, 0, 0),
                       (0, 0, 0),
                       (r * cos(a / 2), r * sin(a / 2), 0),
                       (r * cos(a / 2), -r * sin(a / 2), 0),
                       (0, 0, 0)])
        dimer.calc = calc

        E = []
        F = []
        for d in D:
            dimer.positions[3:, 0] += d - dimer.positions[5, 0]
            E.append(dimer.get_potential_energy())
            F.append(dimer.get_forces())

        F = np.array(F)

        F1 = np.polyval(np.polyder(np.polyfit(D, E, 7)), D)
        F2 = F[:, :3, 0].sum(1)
        error = abs(F1 - F2).max()
        assert error < 0.9

        dimer.set_constraint(FixInternals(
            bonds=[(r, (0, 2)), (r, (1, 2)),
                   (r, (3, 5)), (r, (4, 5))],
            angles_deg=[(angleHOH, (0, 2, 1)), (angleHOH, (3, 5, 4))]))
        opt = BFGS(dimer,
                   trajectory=calc.name + '.traj', logfile=calc.name + 'd.log')
        opt.run(0.01)

        e0 = dimer.get_potential_energy()
        d0 = dimer.get_distance(2, 5)
        R = dimer.positions
        v1 = R[1] - R[5]
        v2 = R[5] - (R[3] + R[4]) / 2
        a0 = np.arccos(np.dot(v1, v2) /
                       (np.dot(v1, v1) * np.dot(v2, v2))**0.5) / np.pi * 180
        fmt = '{0:>20}: {1:.3f} {2:.3f} {3:.3f} {4:.1f}'
        print(fmt.format(calc.name, -min(E), -e0, d0, a0))
