#################################################################################
#     This file is part of Spheres.
#     Copyright (C) 2019  Jesusalva

#     This program is free software: you can redistribute it and/or modify
#     it under the terms of the GNU General Public License as published by
#     the Free Software Foundation, either version 3 of the License, or
#     (at your option) any later version.

#     This program is distributed in the hope that it will be useful,
#     but WITHOUT ANY WARRANTY; without even the implied warranty of
#     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#     GNU General Public License for more details.

#     You should have received a copy of the GNU General Public License
#     along with this program.  If not, see <http://www.gnu.org/licenses/>.
#################################################################################
# Adds an extra layer of security to the server
# Really basic stuff, still better than nothing, though
import threading, time, traceback
from utils import now, stdout, dl_search, ifte
from consts import (BL_UPDATETIME, INT_MAX, BAN_TIME, BAN_AUTHED, BAN_UNAUTHED,
    PACKET_NACK, PACKET_ACK, PACKET_REGX)

blacklist = []

###############################################################
## Startup Methods
# Import K-Line, G-Line and Z-Line
try:
    f=open("Z-Line.txt", "r")
    for ip in f:
        blacklist.append([ip.replace("\n", ""), INT_MAX])
    f.close()
except:
    stdout("No Z-Line.txt config file found")
    pass

try:
    f=open("G-Line.txt", "r")
    for ip in f:
        blacklist.append([ip.replace("\n", ""), INT_MAX])
    f.close()
except:
    stdout("No G-Line.txt config file found")
    pass

try:
    f=open("K-Line.txt", "r")
    for ip in f:
        blacklist.append([ip.replace("\n", ""), INT_MAX])
    f.close()
except:
    stdout("No K-Line.txt config file found")
    pass

# Inform what is current blacklist
#stdout("Blacklist configuration:\n%s\n\n" % str(blacklist))

###############################################################################
## Public Methods
def is_banned(ip):
    global blacklist
    #print("Searching on blacklist")
    bl=dl_search(blacklist, 0, ip)
    print("Blacklist search result: %s" % str(bl))
    if (bl != "ERROR"):
        return True
    else:
        return False

def ban_ip(ip, until=INT_MAX):
    global blacklist
    blacklist.append([ip, until])
    stdout("%s has been banned until %d." % (ip, until))
    # TODO: kick users when they are banned or klined?
    return

def unban_ip(ip):
    global blacklist
    try:
        blacklist.remove(dl_search(blacklist, 0, ip))
        stdout("%s has been unbanned." % (ip))
    except:
        stdout("%s is not banned." % (ip))
    return

def get_score(proto):
    if (proto == PACKET_REGX):
        return 2
    elif proto == PACKET_NACK:
        return 5
    elif proto == PACKET_ACK:
        return 0
    else:
        stdout("\"%s\" is not a valid packet reply code" % str(proto))
        return 0

def score(conn, score):
    #print("Score request: %d" % score)
    conn.MS_score += score

    limit = ifte(conn.MS_auth, BAN_AUTHED, BAN_UNAUTHED)

    if (conn.MS_score >= limit):
        stdout("Banning %s (%d/%d lame)" % (conn.address[0], conn.MS_score, limit))
        ban_ip(conn.address[0], now()+BAN_TIME)
        time.sleep(0.1)
        try:
            conn.close(status=1000, reason="K-Lined")
        except:
            traceback.print_exc()
            print("Failed to close, retrying...")
            try:
                conn.close(conn, status=1000, reason="K-Lined")
                stdout("Connection closed!")
            except:
                traceback.print_exc()
                print("Still failed! Connection was kept alive.")
    return

###############################################################################
## Private Methods
def blacklist_update():
    for ban in blacklist:
        if ban[1] < now():
            blacklist.remove(ban)
            stdout("Unbanning %s..." % ban[0])
    bl_update=threading.Timer(BL_UPDATETIME, blacklist_update)
    bl_update.daemon=True
    bl_update.start()

# Run, and keep running forever
blacklist_update()