#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""Tests for `seamm_ff_util` package."""

import seamm_ff_util  # noqa: F401


def test_middle_bond_torsion_3_explicit(pcff):
    """Test of middle_bond_torsion_3 parameters, which should find
    explicit ones"""

    expected = {
        'V1': '-10.0179',
        'V2': '-2.8145',
        'V3': '0.1665',
        'reference': '1',
        'R0': '1.5300'
    }

    i = 'h'
    j = 'c'
    k = 'c'
    l = 'c_0'  # noqa: E741
    ptype, key, form, parameters = pcff.middle_bond_torsion_3_parameters(
        i, j, k, l
    )
    assert ptype == "explicit"
    assert key == ('c_0', 'c', 'c', 'h')
    assert parameters == expected


def test_middle_bond_torsion_3_explicit_lkji(pcff):
    """known middle_bond_torsion_3 parameters, ordered backwards"""

    expected = {
        'V1': '-10.0179',
        'V2': '-2.8145',
        'V3': '0.1665',
        'reference': '1',
        'R0': '1.5300'
    }

    i = 'c_0'
    j = 'c'
    k = 'c'
    l = 'h'  # noqa: E741
    ptype, key, form, parameters = pcff.middle_bond_torsion_3_parameters(
        i, j, k, l
    )
    assert ptype == "explicit"
    assert key == ('c_0', 'c', 'c', 'h')
    assert parameters == expected


def test_middle_bond_torsion_3_equivalent(pcff):
    """Simple test of middle_bond_torsion_3 parameters using equivalencies"""
    expected = {
        'V1': '-5.5679',
        'V2': '1.4083',
        'V3': '0.3010',
        'reference': '1',
        'R0': '1.5010'
    }

    i = 'h'
    j = 'c'
    k = 'c5'
    l = 'c5'  # noqa: E741
    ptype, key, form, parameters = pcff.middle_bond_torsion_3_parameters(
        i, j, k, l
    )
    assert ptype == "equivalent"
    assert key == ('h', 'c', 'cp', 'cp')
    assert parameters == expected
