"""Test the Nonlinear Block Jacobi solver. """

import unittest

import numpy as np

import openmdao.api as om
from openmdao.test_suite.components.ae_tests import AEComp, AEDriver
from openmdao.test_suite.components.sellar import SellarDis1withDerivatives, SellarDis2withDerivatives
from openmdao.utils.assert_utils import assert_near_equal
from openmdao.utils.mpi import MPI

try:
    from openmdao.vectors.petsc_vector import PETScVector
except ImportError:
    PETScVector = None


class TestNLBlockJacobi(unittest.TestCase):

    def test_feature_basic(self):
        import numpy as np

        import openmdao.api as om
        from openmdao.test_suite.components.sellar import SellarDis1withDerivatives, SellarDis2withDerivatives

        prob = om.Problem()
        model = prob.model

        model.add_subsystem('px', om.IndepVarComp('x', 1.0), promotes=['x'])
        model.add_subsystem('pz', om.IndepVarComp('z', np.array([5.0, 2.0])), promotes=['z'])

        model.add_subsystem('d1', SellarDis1withDerivatives(), promotes=['x', 'z', 'y1', 'y2'])
        model.add_subsystem('d2', SellarDis2withDerivatives(), promotes=['z', 'y1', 'y2'])

        model.add_subsystem('obj_cmp', om.ExecComp('obj = x**2 + z[1] + y1 + exp(-y2)',
                                                   z=np.array([0.0, 0.0]), x=0.0),
                            promotes=['obj', 'x', 'z', 'y1', 'y2'])

        model.add_subsystem('con_cmp1', om.ExecComp('con1 = 3.16 - y1'), promotes=['con1', 'y1'])
        model.add_subsystem('con_cmp2', om.ExecComp('con2 = y2 - 24.0'), promotes=['con2', 'y2'])

        model.linear_solver = om.LinearBlockGS()
        model.nonlinear_solver = om.NonlinearBlockJac()

        prob.setup()

        prob.run_model()

        assert_near_equal(prob['y1'], 25.58830273, .00001)
        assert_near_equal(prob['y2'], 12.05848819, .00001)

    def test_feature_maxiter(self):
        import numpy as np

        import openmdao.api as om
        from openmdao.test_suite.components.sellar import SellarDis1withDerivatives, SellarDis2withDerivatives

        prob = om.Problem()
        model = prob.model

        model.add_subsystem('px', om.IndepVarComp('x', 1.0), promotes=['x'])
        model.add_subsystem('pz', om.IndepVarComp('z', np.array([5.0, 2.0])), promotes=['z'])

        model.add_subsystem('d1', SellarDis1withDerivatives(), promotes=['x', 'z', 'y1', 'y2'])
        model.add_subsystem('d2', SellarDis2withDerivatives(), promotes=['z', 'y1', 'y2'])

        model.add_subsystem('obj_cmp', om.ExecComp('obj = x**2 + z[1] + y1 + exp(-y2)',
                                                   z=np.array([0.0, 0.0]), x=0.0),
                            promotes=['obj', 'x', 'z', 'y1', 'y2'])

        model.add_subsystem('con_cmp1', om.ExecComp('con1 = 3.16 - y1'), promotes=['con1', 'y1'])
        model.add_subsystem('con_cmp2', om.ExecComp('con2 = y2 - 24.0'), promotes=['con2', 'y2'])

        model.linear_solver = om.LinearBlockGS()

        nlbgs = model.nonlinear_solver = om.NonlinearBlockJac()
        nlbgs.options['maxiter'] = 4

        prob.setup()

        prob.run_model()

        assert_near_equal(prob['y1'], 25.5723813937, .00001)
        assert_near_equal(prob['y2'], 12.0542542372, .00001)

    def test_feature_rtol(self):
        import numpy as np

        import openmdao.api as om
        from openmdao.test_suite.components.sellar import SellarDis1withDerivatives, SellarDis2withDerivatives

        prob = om.Problem()
        model = prob.model

        model.add_subsystem('px', om.IndepVarComp('x', 1.0), promotes=['x'])
        model.add_subsystem('pz', om.IndepVarComp('z', np.array([5.0, 2.0])), promotes=['z'])

        model.add_subsystem('d1', SellarDis1withDerivatives(), promotes=['x', 'z', 'y1', 'y2'])
        model.add_subsystem('d2', SellarDis2withDerivatives(), promotes=['z', 'y1', 'y2'])

        model.add_subsystem('obj_cmp', om.ExecComp('obj = x**2 + z[1] + y1 + exp(-y2)',
                                                   z=np.array([0.0, 0.0]), x=0.0),
                            promotes=['obj', 'x', 'z', 'y1', 'y2'])

        model.add_subsystem('con_cmp1', om.ExecComp('con1 = 3.16 - y1'), promotes=['con1', 'y1'])
        model.add_subsystem('con_cmp2', om.ExecComp('con2 = y2 - 24.0'), promotes=['con2', 'y2'])

        model.linear_solver = om.LinearBlockGS()

        nlbgs = model.nonlinear_solver = om.NonlinearBlockJac()
        nlbgs.options['rtol'] = 1e-3

        prob.setup()

        prob.run_model()

        assert_near_equal(prob['y1'], 25.5891491526, .00001)
        assert_near_equal(prob['y2'], 12.0569142166, .00001)

    def test_feature_atol(self):
        import numpy as np

        import openmdao.api as om
        from openmdao.test_suite.components.sellar import SellarDis1withDerivatives, SellarDis2withDerivatives

        prob = om.Problem()
        model = prob.model

        model.add_subsystem('px', om.IndepVarComp('x', 1.0), promotes=['x'])
        model.add_subsystem('pz', om.IndepVarComp('z', np.array([5.0, 2.0])), promotes=['z'])

        model.add_subsystem('d1', SellarDis1withDerivatives(), promotes=['x', 'z', 'y1', 'y2'])
        model.add_subsystem('d2', SellarDis2withDerivatives(), promotes=['z', 'y1', 'y2'])

        model.add_subsystem('obj_cmp', om.ExecComp('obj = x**2 + z[1] + y1 + exp(-y2)',
                                                   z=np.array([0.0, 0.0]), x=0.0),
                            promotes=['obj', 'x', 'z', 'y1', 'y2'])

        model.add_subsystem('con_cmp1', om.ExecComp('con1 = 3.16 - y1'), promotes=['con1', 'y1'])
        model.add_subsystem('con_cmp2', om.ExecComp('con2 = y2 - 24.0'), promotes=['con2', 'y2'])

        model.linear_solver = om.LinearBlockGS()

        nlbgs = model.nonlinear_solver = om.NonlinearBlockJac()
        nlbgs.options['atol'] = 1e-2

        prob.setup()

        prob.run_model()

        assert_near_equal(prob['y1'], 25.5886171567, .00001)
        assert_near_equal(prob['y2'], 12.05848819, .00001)


@unittest.skipUnless(MPI and PETScVector, "MPI and PETSc are required.")
class TestNonlinearBlockJacobiMPI(unittest.TestCase):

    N_PROCS = 2

    def test_reraise_analylsis_error(self):
        prob = om.Problem()
        model = prob.model

        model.add_subsystem('p1', om.IndepVarComp('x', 0.5))
        model.add_subsystem('p2', om.IndepVarComp('x', 3.0))
        sub = model.add_subsystem('sub', om.ParallelGroup())

        sub.add_subsystem('c1', AEComp())
        sub.add_subsystem('c2', AEComp())
        sub.nonlinear_solver = om.NonlinearBlockJac()

        model.add_subsystem('obj', om.ExecComp(['val = x1 + x2']))

        model.connect('p1.x', 'sub.c1.x')
        model.connect('p2.x', 'sub.c2.x')
        model.connect('sub.c1.y', 'obj.x1')
        model.connect('sub.c2.y', 'obj.x2')

        prob.driver = AEDriver()

        prob.setup()

        handled = prob.run_driver()
        self.assertTrue(handled)


if __name__ == "__main__":
    unittest.main()
