#!/usr/bin/env python
# (C) 2022 Cadence Design Systems, Inc. (Cadence) 
# All rights reserved.
# TERMS FOR USE OF SAMPLE CODE The software below ("Sample Code") is
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# subject to these terms. Cadence claims no rights to Customer's
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# current license or subscription to the applicable Cadence offering.
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# EXPRESS OR IMPLIED.  OPENEYE DISCLAIMS ALL WARRANTIES, INCLUDING, BUT
# NOT LIMITED TO, WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
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import sys
from openeye import oechem
from openeye import oezap

KCalsPerKT = 0.59
KCalsPerSqAngstrom = 0.010


def main(argv=[__name__]):

    if len(argv) != 2:
        oechem.OEThrow.Usage("%s <molfile>" % argv[0])

    epsin = 1.0

    zap = oezap.OEZap()
    zap.SetInnerDielectric(epsin)
    zap.SetGridSpacing(0.5)

    area = oezap.OEArea()

    mol = oechem.OEGraphMol()
    ifs = oechem.oemolistream()
    if not ifs.open(argv[1]):
        oechem.OEThrow.Fatal("Unable to open %s for reading" % argv[1])
    oechem.OEThrow.Info("%-20s %6s\n" % ("Title", "Vacuum->Water(kcal)"))
    while oechem.OEReadMolecule(ifs, mol):
        oechem.OEAssignBondiVdWRadii(mol)
        oechem.OEMMFFAtomTypes(mol)
        oechem.OEMMFF94PartialCharges(mol)
        zap.SetMolecule(mol)
        solv = zap.CalcSolvationEnergy()
        aval = area.GetArea(mol)
        oechem.OEThrow.Info("%-20s   %6.2f" % (mol.GetTitle(),
                                               KCalsPerKT*solv+KCalsPerSqAngstrom*aval))

    return 0


if __name__ == "__main__":
    sys.exit(main(sys.argv))