internal

#!/usr/bin/env python3
'Command line program to exercise/test/debug the _internal command.'
# Mark Blakeney, Oct 2019
import sys
import importlib
import argparse
from pathlib import Path

CMD = '_internal'
GESTURE = 'swipe'
PROG = Path(sys.argv[0]).resolve()
NAME = Path.cwd().name
CACHE = Path.home() / '.cache' / PROG.name

def import_path(path, add_to_path=False):
    'Import given module path'
    modname = Path(path).stem.replace('-', '_')
    spec = importlib.util.spec_from_loader(modname,
            importlib.machinery.SourceFileLoader(modname, path))
    module = importlib.util.module_from_spec(spec)
    spec.loader.exec_module(module)
    if add_to_path:
        sys.modules[modname] = module
    return module

opt = argparse.ArgumentParser(description=__doc__)
opt.add_argument('-c', '--conffile',
        help='alternative configuration file')
opt.add_argument('-i', '--initial', type=int,
        help='initial desktop')
opt.add_argument('-C', '--cols', type=int, default=1,
        help='number of columns')
opt.add_argument('-t', '--text', action='store_true',
        help='output desktop change in text')
opt.add_argument('-n', '--nocache', action='store_true',
        help='do not use cache')
opt.add_argument('num', type=int,
        help='number of desktops')
opt.add_argument('action', nargs='?',
        help='action to perform')
opt.add_argument('-d', '--display', type=int,
        help=argparse.SUPPRESS)
opt.add_argument('-s', '--set', type=int, help=argparse.SUPPRESS)
args = opt.parse_args()

def showgrid(pos, num, cols):
    print()
    for i in range(num):
        end = '\n' if (i % cols) == (cols - 1) else ''
        if i == pos:
            print(f' {i:02} ', end=end)
        else:
            print(' ** ', end=end)
    if end != '\n':
        print()

if args.set is not None:
    print(args.set)
    sys.exit(0)

if args.display is not None:
    for i in range(args.num):
        ds = '*' if i == args.display else '-'
        print(f'{i} {ds} -')
    sys.exit(0)

if args.initial is None:
    if args.nocache:
        opt.error('Initial value must be specified')
    if not CACHE.exists():
        opt.error('Need initial desktop specified')
    start = int(CACHE.read_text().strip())
else:
    start = args.initial

lg = import_path(NAME)
icmd = lg.internal_commands[CMD]

icmd.CMDLIST = f'{PROG} -d {start} {args.num}'.split()
icmd.CMDSET = f'{PROG} {args.num} -s'.split()

lg.read_conf(args.conffile, NAME + '.conf')
motions = lg.handlers[GESTURE.upper()].motions
actions = {k: v for k, v in motions.items() if isinstance(v, icmd)}

if not args.action or args.action not in actions:
    opt.error(f'action must be one of {list(actions.keys())}')

cmd = motions[args.action]
print(f'Command "{GESTURE} {args.action} is "{cmd}"')
res = cmd.run(block=True)

if res:
    end = int(res.strip())
    if not args.nocache:
        CACHE.write_text(str(end))
else:
    end = start

if end < 0 or end >= args.num:
    sys.exit(f'Desktop change from {start} to {end}, '
            f'out of range 0 to <{args.num}!')

if args.text:
    if start != end:
        print(f'Desktop change from {start} to {end}')
    else:
        print('No change')
else:
    showgrid(start, args.num, args.cols)
    showgrid(end, args.num, args.cols)