from __future__ import print_function
from ortools.linear_solver import pywraplp
import sys

def main():
    # get arguments
    hours_string = sys.argv[1]
    hours_data = hours_string.split('-')

    # initialize hours
    hours = [
        ['00', 0],
        ['01', 0],
        ['02', 0],
        ['03', 0],
        ['04', 0],
        ['05', 0],
        ['06', 0],
        ['07', 0],
        ['08', 0],
        ['09', 0],
        ['10', 0],
        ['11', 0],
        ['12', 0],
        ['13', 0],
        ['14', 0],
        ['15', 0],
        ['16', 0],
        ['17', 0],
        ['18', 0],
        ['19', 0],
        ['20', 0],
        ['21', 0],
        ['22', 0],
        ['23', 0]]

    # set hours from argument
    for i in range(0, len(hours_data)):
        hours[i][1] = int(hours_data[i])


    # all shifts available
    shifts = [
        ['00 - 09', 0, 1, 2, 3, 4, 5, 6, 7, 8],
        ['01 - 10', 1, 2, 3, 4, 5, 6, 7, 8, 9],
        ['02 - 11', 2, 3, 4, 5, 6, 7, 8, 9, 10],
        ['03 - 12', 3, 4, 5, 6, 7, 8, 9, 10, 11],
        ['04 - 13', 4, 5, 6, 7, 8, 9, 10, 11, 12],
        ['05 - 14', 5, 6, 7, 8, 9, 10, 11, 12, 13],
        ['06 - 15', 6, 7, 8, 9, 10, 11, 12, 13, 14],
        ['07 - 16', 7, 8, 9, 10, 11, 12, 13, 14, 15],
        ['08 - 17', 8, 9, 10, 11, 12, 13, 14, 15, 16],
        ['09 - 18', 9, 10, 11, 12, 13, 14, 15, 16, 17],
        ['10 - 19', 10, 11, 12, 13, 14, 15, 16, 17, 18],
        ['11 - 20', 11, 12, 13, 14, 15, 16, 17, 18, 19],
        ['12 - 21', 12, 13, 14, 15, 16, 17, 18, 19, 20],
        ['13 - 22', 13, 14, 15, 16, 17, 18, 19, 20, 21],
        ['14 - 23', 14, 15, 16, 17, 18, 19, 20, 21, 22],
        ['15 - 00', 15, 16, 17, 18, 19, 20, 21, 22, 23],
        ['16 - 01', 16, 17, 18, 19, 20, 21, 22, 23, 0],
        ['17 - 02', 17, 18, 19, 20, 21, 22, 23, 0, 1],
        ['18 - 03', 18, 19, 20, 21, 22, 23, 0, 1, 2],
        ['19 - 04', 19, 20, 21, 22, 23, 0, 1, 2, 3],
        ['20 - 05', 20, 21, 22, 23, 0, 1, 2, 3, 4],
        ['21 - 06', 21, 22, 23, 0, 1, 2, 3, 4, 5],
        ['22 - 07', 22, 23, 0, 1, 2, 3, 4, 5, 6],
        ['23 - 08', 23, 0, 1, 2, 3, 4, 5, 6, 7]]

    # instantiate glop solver
    solver = pywraplp.Solver('SolveSchedule', pywraplp.Solver.CBC_MIXED_INTEGER_PROGRAMMING)

    # solver variables
    solv_shifts = [[]] * len(shifts)

    # objective
    objective = solver.Objective()

    # variables for shifts
    for i in range(0, len(shifts)):
        solv_shifts[i] = solver.IntVar(0, solver.infinity(), shifts[i][0])
        # objective is to minimize number of shifts
        objective.SetCoefficient(solv_shifts[i], 1)

    objective.SetMinimization()

    # set constraints
    constraints = [0] * len(hours)
    for hour_index in range(0, len(hours)):
        # hour personnel should be equal or less than shift personnel that covers those hours
        constraints[hour_index] = solver.Constraint(hours[hour_index][1], solver.infinity())
        for shift_index in range(0, len(shifts)):
            # get each shift's hour coverage
            for shift_hour_index in range(1, len(shifts[shift_index])):
                # check if shift covers that hour
                # NOTE: this can still be optimized later via indexing
                if shifts[shift_index][shift_hour_index] == hour_index:
                    # print('hour', hour_index, 'in shift index -', shift_index)
                    constraints[hour_index].SetCoefficient(solv_shifts[shift_index], 1)

    # solve it!
    status = solver.Solve()

    if status == solver.OPTIMAL:
        #print('Optimal solution found!')
        #print('Number of variables =', solver.NumVariables())
        #print('Number of constraints =', solver.NumConstraints())
        for i in range(0, len(shifts)):
            result = solv_shifts[i].solution_value()
            if result > 0:
                print(i, '-', int(solv_shifts[i].solution_value()), sep='')
    else:
        if status == solver.FEASIBLE:
            print('Feasible solution found!')
        else:
            print('Could not solve problem.')

if __name__ == '__main__':
  main()