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from __future__ import print_function
from ortools.constraint_solver import pywrapcp


# Create the solver.
solver = pywrapcp.Solver('Vendors scheduling')

#
# data
#
num_vendors = 9
num_hours = 10
num_work_types = 1

trafic = [100, 500, 100, 200, 320, 300, 200, 220, 300, 120]
max_trafic_per_vendor = 100

# Last columns are :
#   index_of_the_schedule, sum of worked hours (per work type).
# The index is useful for branching.
possible_schedules = [[1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 8],
                      [1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 4],
                      [0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 2, 5],
                      [0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 3, 4],
                      [1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 4, 3],
                      [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0]]

num_possible_schedules = len(possible_schedules)
selected_schedules = []
vendors_stat = []
hours_stat = []

#
# declare variables
#
x = {}

for i in range(num_vendors):
  tmp = []
  for j in range(num_hours):
    x[i, j] = solver.IntVar(0, num_work_types, 'x[%i,%i]' % (i, j))
    tmp.append(x[i, j])
  selected_schedule = solver.IntVar(0, num_possible_schedules - 1,
                                    's[%i]' % i)
  hours = solver.IntVar(0, num_hours, 'h[%i]' % i)
  selected_schedules.append(selected_schedule)
  vendors_stat.append(hours)
  tmp.append(selected_schedule)
  tmp.append(hours)

  solver.Add(solver.AllowedAssignments(tmp, possible_schedules))

#
# Statistics and constraints for each hour
#
for j in range(num_hours):
  workers = solver.Sum([x[i, j] for i in range(num_vendors)]).Var()
  hours_stat.append(workers)
  solver.Add(workers * max_trafic_per_vendor >= trafic[j])

#
# Redundant constraint: sort selected_schedules
#
for i in range(num_vendors - 1):
  solver.Add(selected_schedules[i] <= selected_schedules[i + 1])

#
# Search
#
db = solver.Phase(selected_schedules, solver.CHOOSE_FIRST_UNBOUND,
                  solver.ASSIGN_MIN_VALUE)

solver.NewSearch(db)

num_solutions = 0
while solver.NextSolution():
  num_solutions += 1

  for i in range(num_vendors):
    print('Vendor %i: ' % i,
          possible_schedules[selected_schedules[i].Value()])
  print()

  print('Statistics per day:')
  for j in range(num_hours):
    print('Day%2i: ' % j, end=' ')
    print(hours_stat[j].Value(), end=' ')
    print()
  print()

solver.EndSearch()
print()
print('num_solutions:', num_solutions)
print('failures:', solver.Failures())
print('branches:', solver.Branches())
print('WallTime:', solver.WallTime(), 'ms')