wlan

#!/usr/bin/python3

import json
import os
import re
import subprocess
from optparse import OptionParser

import wifi


class Networks:
    def __init__(self, path="~/.wlan.json"):
        self.PATH = os.path.abspath(os.path.expanduser(path))
        self.NETS = {}
        if not os.path.exists(self.PATH):
            self._save()
        else:
            self._load()

    def _load(self):
        with open(self.PATH, "r") as f:
            self.NETS = json.load(f)

    def _save(self):
        with open(self.PATH, "w") as f:
            json.dump(self.NETS, f)

    def ssids(self):
        return list(self.NETS.keys())

    def password(self, ssid):
        return self.NETS.get(ssid, None)

    def set_password(self, ssid, password):
        self.NETS[ssid] = password
        self._save()
        return self.NETS

NET = Networks()

def interfaces():
    return os.listdir("/sys/class/net/")

def networks_on(interface):
    # https://stackoverflow.com/questions/53246654/how-to-find-all-and-connect-all-available-wifi-signals-using-python
    # https://docs.python.org/3/howto/curses.html
    try:
        return [c.ssid for c in wifi.Cell.all(interface)]
    except wifi.exceptions.InterfaceError:
        return []

def available_networks():
    for i in interfaces():
        for n in networks_on(i):
            if n:
                yield n

def current_ssid():
    raw = subprocess.check_output("iwgetid").decode("utf-8")
    return re.search("ESSID:\"(.*?)\"", raw).group(1)


def connect_to(ssid, password, interface=None):
    cmd = f"nmcli d wifi connect {ssid} password {password}"
    if interface:
        cmd += f"iface {interface}"
    return os.system(cmd)


if __name__ == "__main__":
    parser = OptionParser()
    parser.add_option("-p", "--password", dest="password", default=None,
                      help="Specify a password for the given network. Ignored if no network is specified.")
    parser.add_option("-l", "--list", dest="list_networks", default=False, action="store_true",
                      help="If passed, just list available networks instead of connecting")
    parser.add_option("-f", "--force", dest="force", default=False, action="store_true",
                      help="If passed, connect even if already connected to a network")
    (options, args) = parser.parse_args()

    if options.list_networks:
        print(list(available_networks()))
        exit(0)

    ssid = args[0] if args else None
    if current_ssid() and not options.force:
        print(f"Already connected to {current_ssid()}...")
        exit(0)

    if ssid and options.password:
        print(f"Connecting to {ssid} with given password...")
        NET.set_password(ssid, options.password)
        exit(connect_to(ssid, options.password))
    elif ssid and NET.password(ssid):
        print(f"Connecting to {ssid} with stored password...")
        exit(connect_to(ssid, NET.password(ssid)))
    elif ssid:
        print(f"I don't know the password for {ssid}...")
        exit(1)
    else:
        print("Searching for known networks...")
        known = set(NET.ssids())
        print(f"   {known}")
        for ssid in available_networks():
            if ssid in known:
                print(f"   Found {ssid}. Connecting...")
                exit(connect_to(ssid, NET.password(ssid)))
        print("   No known networks found...")
        exit(1)