# Copyright 2010-2014 Google
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Unit tests for python/constraint_solver.swig. Not exhaustive."""

import sys

from ortools.constraint_solver import model_pb2
from ortools.constraint_solver import pywrapcp


def test_member():
  print 'test_member'
  solver = pywrapcp.Solver('test member')
  x = solver.IntVar(1, 10, 'x')
  ct = x.Member([1, 2, 3, 5])
  print ct


def test_sparse_var():
  print 'test_sparse_var'
  solver = pywrapcp.Solver('test_sparse_var')
  x = solver.IntVar([1, 3, 5], 'x')
  print x


def test_modulo():
  print 'test_modulo'
  solver = pywrapcp.Solver('test_modulo')
  x = solver.IntVar(0, 10, 'x')
  y = solver.IntVar(2, 4, 'y')
  print x % 3
  print x % y


def test_limit():
  solver = pywrapcp.Solver('test_limit')
  # TODO(user): expose the proto-based MakeLimit() API in or-tools and test it
  # here.
  time = 10000  # ms
  branches = 10
  failures = sys.maxint
  solutions = sys.maxint
  smart_time_check = True
  cumulative = False
  limit = solver.Limit(time, branches, failures, solutions, smart_time_check,
                       cumulative)
  print limit


def test_export():
  print 'test_export'
  solver = pywrapcp.Solver('test_export')
  x = solver.IntVar(1, 10, 'x')
  ct = x.Member([1, 2, 3, 5])
  solver.Add(ct)
  proto = model_pb2.CPModelProto()
  proto.model = 'wrong name'
  solver.ExportModel(proto)
  print repr(proto)
  print str(proto)


class SearchMonitorTest(pywrapcp.SearchMonitor):

  def __init__(self, solver, nexts):
    pywrapcp.SearchMonitor.__init__(self, solver)
    self._nexts = nexts

  def BeginInitialPropagation(self):
    print self._nexts

  def EndInitialPropagation(self):
    print self._nexts


def test_search_monitor():
  print 'test_search_monitor'
  solver = pywrapcp.Solver('test search_monitor')
  x = solver.IntVar(1, 10, 'x')
  ct = (x == 3)
  solver.Add(ct)
  db = solver.Phase([x], solver.CHOOSE_FIRST_UNBOUND, solver.ASSIGN_MIN_VALUE)
  monitor = SearchMonitorTest(solver, x)
  solver.Solve(db, monitor)


class DemonTest(pywrapcp.PyDemon):

  def __init__(self, x):
    pywrapcp.PyDemon.__init__(self)
    self._x = x
    print 'Demon built'

  def Run(self, solver):
    print 'in Run(), saw ' + str(self._x)


def test_demon():
  print 'test_demon'
  solver = pywrapcp.Solver('test_demon')
  x = solver.IntVar(1, 10, 'x')
  demon = DemonTest(x)
  demon.Run(solver)


class ConstraintTest(pywrapcp.PyConstraint):

  def __init__(self, solver, x):
    pywrapcp.Constraint.__init__(self, solver)
    self._x = x
    print 'Constraint built'

  def Post(self):
    print 'in Post()'
    self._demon = DemonTest(self._x)
    self._x.WhenBound(self._demon)
    print 'out of Post()'

  def InitialPropagate(self):
    print 'in InitialPropagate()'
    self._x.SetMin(5)
    print self._x
    print 'out of InitialPropagate()'


def test_constraint():
  print 'test_constraint'
  solver = pywrapcp.Solver('test_constraint')
  x = solver.IntVar(1, 10, 'x')
  myct = ConstraintTest(solver, x)
  solver.Add(myct)
  db = solver.Phase([x], solver.CHOOSE_FIRST_UNBOUND, solver.ASSIGN_MIN_VALUE)
  solver.Solve(db)


class InitialPropagateDemon(pywrapcp.PyDemon):

  def __init__(self, ct):
    pywrapcp.Demon.__init__(self)
    self._ct = ct

  def Run(self, solver):
    self._ct.InitialPropagate()


class DumbGreaterOrEqualToFive(pywrapcp.PyConstraint):

  def __init__(self, solver, x):
    pywrapcp.Constraint.__init__(self, solver)
    self._x = x

  def Post(self):
    self._demon = InitialPropagateDemon(self)
    self._x.WhenBound(self._demon)

  def InitialPropagate(self):
    if self._x.Bound():
      if self._x.Value() < 5:
        print 'Reject %d' % self._x.Value()
        self.solver().Fail()
      else:
        print 'Accept %d' % self._x.Value()


def test_failing_constraint():
  print 'test_failing_constraint'
  solver = pywrapcp.Solver('test failing constraint')
  x = solver.IntVar(1, 10, 'x')
  myct = DumbGreaterOrEqualToFive(solver, x)
  solver.Add(myct)
  db = solver.Phase([x], solver.CHOOSE_FIRST_UNBOUND, solver.ASSIGN_MIN_VALUE)
  solver.Solve(db)


def test_domain_iterator():
  print 'test_domain_iterator'
  solver = pywrapcp.Solver('test_domain_iterator')
  x = solver.IntVar([1, 2, 4, 6], 'x')
  for i in x.DomainIterator():
    print i


class WatchDomain(pywrapcp.PyDemon):

  def __init__(self, x):
    pywrapcp.Demon.__init__(self)
    self._x = x

  def Run(self, solver):
    for i in self._x.HoleIterator():
      print 'Removed %d' % i


class HoleConstraintTest(pywrapcp.PyConstraint):

  def __init__(self, solver, x):
    pywrapcp.Constraint.__init__(self, solver)
    self._x = x

  def Post(self):
    self._demon = WatchDomain(self._x)
    self._x.WhenDomain(self._demon)

  def InitialPropagate(self):
    self._x.RemoveValue(5)


def test_hole_iterator():
  print 'test_hole_iterator'
  solver = pywrapcp.Solver('test_hole_iterator')
  x = solver.IntVar(1, 10, 'x')
  myct = HoleConstraintTest(solver, x)
  solver.Add(myct)
  db = solver.Phase([x], solver.CHOOSE_FIRST_UNBOUND, solver.ASSIGN_MIN_VALUE)
  solver.Solve(db)


class BinarySum(pywrapcp.PyConstraint):

  def __init__(self, solver, x, y, z):
    pywrapcp.Constraint.__init__(self, solver)
    self._x = x
    self._y = y
    self._z = z

  def Post(self):
    self._demon = InitialPropagateDemon(self)
    self._x.WhenRange(self._demon)
    self._y.WhenRange(self._demon)
    self._z.WhenRange(self._demon)

  def InitialPropagate(self):
    self._z.SetRange(self._x.Min() + self._y.Min(),
                     self._x.Max() + self._y.Max())
    self._x.SetRange(self._z.Min() - self._y.Max(),
                     self._z.Max() - self._y.Min())
    self._y.SetRange(self._z.Min() - self._x.Max(),
                     self._z.Max() - self._x.Min())


def test_sum_constraint():
  print 'test_sum_constraint'
  solver = pywrapcp.Solver('test_sum_constraint')
  x = solver.IntVar(1, 5, 'x')
  y = solver.IntVar(1, 5, 'y')
  z = solver.IntVar(1, 5, 'z')
  binary_sum = BinarySum(solver, x, y, z)
  solver.Add(binary_sum)
  db = solver.Phase([x, y, z], solver.CHOOSE_FIRST_UNBOUND,
                    solver.ASSIGN_MIN_VALUE)
  solver.NewSearch(db)
  while solver.NextSolution():
    print '%d + %d == %d' % (x.Value(), y.Value(), z.Value())
  solver.EndSearch()


def main():
  test_member()
  test_sparse_var()
  test_modulo()
  test_limit()
  # TODO(user): expose ExportModel() in python and re-enable this test.
  # test_export()
  test_search_monitor()
  test_demon()
  test_failing_constraint()
  test_constraint()
  test_domain_iterator()
  test_hole_iterator()
  test_sum_constraint()


if __name__ == '__main__':
  main()