from subprocess import call
import os
def tsp(points=[], max_time=10, mode=None):
    """Wraps the concorde and linkern binaries.
    Automatically uses concorde for less than 1000 points,
    and uses linkern for more. Maximum of 10 seconds only
    applies to linkern. mode can also be set manually."""
    if len(points) < 3:
        return list(range(len(points)))
    if mode is None:
        if len(points) < 1000:
            mode = 'concorde'
        else:
            mode = 'linkern'
    with open('concorde.dat', 'w') as fp:
        fp.write('TYPE : TSP\n')
        fp.write('DIMENSION : {}\n'.format(len(points)))
        fp.write('EDGE_WEIGHT_TYPE : EUC_2D\n')
        fp.write('NODE_COORD_SECTION\n')
        for i, point in enumerate(points):
            fp.write('{} {} {}\n'.format(i, point[0], point[1]))
        fp.write('EOF\n')
    if mode == 'concorde':
        cmd = 'concorde -x -o concorde.sol concorde.dat'
    if mode == 'linkern':
        cmd = 'linkern -Q -r 1 -t {} -o concorde.sol concorde.dat'.format(max_time)
    call(cmd.split(' '))
    os.remove('concorde.dat')
    with open('concorde.sol') as fp:
        entries = fp.read().split()
        if mode == 'concorde':
            sol = entries[1:]
        else:
            sol = entries[2::3]
        sol = map(int, sol)
    os.remove('concorde.sol')
    return sol