#  rapper based tests of some PySP examples, started by DLW, Oct 2018
# ___________________________________________________________________________
#
#  Pyomo: Python Optimization Modeling Objects
#  Copyright 2018 National Technology and Engineering Solutions of Sandia, LLC
#  Under the terms of Contract DE-NA0003525 with National Technology and 
#  Engineering Solutions of Sandia, LLC, the U.S. Government retains certain 
#  rights in this software.
#  This software is distributed under the 3-clause BSD License.
#  ___________________________________________________________________________

import collections
import math
import sys

import pyutilib.th as unittest
import tempfile
import sys
import os
import shutil
import json
import pyomo.environ as pyo
import pyomo.pysp.util.rapper as rapper
from pyomo.pysp.scenariotree.tree_structure_model import CreateAbstractScenarioTreeModel
import pyomo as pyomoroot

solvername = "ipopt" # could use almost any solver

class Example_via_rapper(unittest.TestCase):
    """ Test some examples using rapper."""

    def setUp(self):
        """pre-test setup"""
        ######## make a temp dir to which files can be copied  #####
        self.tdir = tempfile.mkdtemp()    #TemporaryDirectory().name
        sys.path.insert(1,self.tdir)

        """ During debugging, local files might get in the way
        of finding the file in the temp dir, so we cd there."""
        self.savecwd = os.getcwd()
        os.chdir(self.tdir)

        p = str(pyomoroot.__path__)
        l = p.find("'")
        r = p.find("'", l+1)
        pyomorootpath = p[l+1:r]
        farmpath = pyomorootpath + os.sep + ".." + os.sep + "examples" + \
                   os.sep + "pysp" + os.sep + "farmer"
        self.farmpath = os.path.abspath(farmpath)
        
    def tearDown(self):
        # from GH: This step is key, as Python keys off the name of the module, not the location.
        #       So, different reference models in different directories won't be detected.
        #       If you don't do this, the symptom is a model that doesn't have the attributes
        #       that the data file expects.
        if "ReferenceModel" in sys.modules:
            del sys.modules["ReferenceModel"]
            
        os.chdir(self.savecwd)

    def test_famer_netx(self):
        """ solve the ef and check some post solution code"""
        shutil.copyfile(self.farmpath + os.sep + "concreteNetX" +\
                        os.sep + "ReferenceModel.py",
                        self.tdir + os.sep + "ReferenceModel.py")
        import ReferenceModel as RM
        g = RM.pysp_scenario_tree_model_callback()
        stsolver = rapper.StochSolver("ReferenceModel",
                                      fsfct = "pysp_instance_creation_callback",
                                      tree_model  = g)
        ef_sol = stsolver.solve_ef(solvername)
        assert(ef_sol.solver.termination_condition \
               ==  pyo.TerminationCondition.optimal)
        obj = stsolver.root_E_obj()
        assert(abs(-108385 - obj) < 100) # any solver should get this close

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