#!/opt/imunify360/venv/bin/python3

import glob
import ipaddress
import os
import random
import re
import shutil
import string
import subprocess
import sys


class Panel:

    def __init__(self, host_addresses):
        self.host_addresses = set()
        if host_addresses:
            self.host_addresses.update(host_addresses)

    @classmethod
    def detect(cls):
        if not cls.detect_path:
            return False
        return os.path.exists(cls.detect_path)

    def get_destinations(self):
        data = {}
        for ip, domains in self.additional.items():
            for domain in domains:
                data[domain] = ip
        return data

    def get_ssl_mapping(self):
        data = {}
        for ip, domains in self.additional.items():
            data[ip] = sorted(domains)[0]
        if self.main_ip and self.first_domain:
            data[self.main_ip] = self.first_domain
        return data


class cPanel(Panel):

    detect_path = '/usr/local/cpanel/cpanel'
    domain_ips_path = '/etc/domainips'
    main_address_path = '/var/cpanel/mainip'
    domain_users_path = '/etc/domainusers'

    def prepare(self):
        all_domains = self._get_domains()
        self.main_ip = self._get_main_ip()
        self.additional = self._get_additional()
        if not all_domains:
            self.first_domain = None
            return
        diff = sorted(
            all_domains.difference(
                *self.additional.values()))
        self.first_domain = diff[0] if diff else None

    @classmethod
    def _get_domains(cls):
        domains = set()
        try:
            with open(cls.domain_users_path) as f:
                for line in f:
                    _, domain = [i.strip() for i in line.split(':')]
                    domains.add(domain)
        except Exception:
            pass
        return domains

    def _get_additional(self):
        addresses = {}
        if not os.path.exists(self.domain_ips_path):
            return addresses
        try:
            with open(self.domain_ips_path) as f:
                for line in f:
                    if line.startswith('#'):
                        continue
                    if ':' not in line:
                        continue
                    ip, domain = [i.strip() for i in line.split(':', 1)]
                    if not ip:
                        continue
                    if self.host_addresses and ip not in self.host_addresses:
                        continue
                    if ip not in addresses:
                        addresses[ip] = []
                    addresses[ip].append(domain)
        except Exception:
            pass
        return addresses

    @classmethod
    def _get_main_ip(cls):
        try:
            with open(cls.main_address_path) as f:
                return f.read().strip()
        except Exception:
            return


class Plesk(Panel):

    detect_path = '/usr/sbin/plesk'
    passwd_path = '/etc/psa/.psa.shadow'

    @classmethod
    def _get_plesk_passwd(cls):
        try:
            with open(cls.passwd_path) as f:
                return f.read()
        except Exception:
            return

    @classmethod
    def _find_main_ip(cls, ip_domains):
        """
        Attempt to detect main IP address
        """
        # Find 'shared' ip with Plesk utility
        ip_info = cls._get_ip_info()
        if ip_info:
            for ip in ip_domains.keys():
                if ip_info.get(ip):         # Current IP maps to True
                    return ip               # OK. Found it. Exit

        # Let the main ip be IP with max number of domains
        max_count = 0
        max_ip = None
        for ip, domains in ip_domains.items():
            count = len(domains)
            if count > max_count:
                max_count = count
                max_ip = ip
        return max_ip

    def _get_domain_ips(self):
        data = {}
        passwd = self._get_plesk_passwd()
        if not passwd:
            return data
        env = {'MYSQL_PWD': passwd}
        query = ("""SELECT dom.name, iad.ip_address FROM domains """
                 """dom LEFT JOIN DomainServices d ON (dom.id = d.dom_id """
                 """AND d.type = 'web') LEFT JOIN IpAddressesCollections ia """
                 """ON ia.ipCollectionId = d.ipCollectionId LEFT JOIN """
                 """IP_Addresses iad ON iad.id = ia.ipAddressId""")
        cmd = ['mysql', '-u', 'admin', '-Dpsa', '-e', query]
        try:
            p = subprocess.Popen(
                cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE,
                universal_newlines=True, env=env)
            out, err = p.communicate()
        except (subprocess.CalledProcessError, FileNotFoundError):
            return data

        if not out:
            return data
        for line in out.splitlines():
            domain, ip = line.split()
            if not ip:
                continue
            if self.host_addresses and ip not in self.host_addresses:
                continue
            if ip not in data:
                data[ip] = []
            data[ip].append(domain)
        return data

    @classmethod
    def _get_ip_info(cls):
        data = {}
        patt = re.compile(
            r"""[^:]+:      # Interface name, e.g 'eth0:'
            (?P<ip>[^/]+)   # all symbols before forward slash
            """, re.VERBOSE)

        cmd = ['plesk', 'bin', 'ipmanage', '--ip_list']
        try:
            out = subprocess.check_output(
                cmd, stderr=subprocess.DEVNULL, universal_newlines=True)
        except subprocess.CalledProcessError:
            return data

        if not out:
            return data

        for line in out.splitlines():
            splitted = line.split()

            if not splitted:
                continue

            if len(splitted) < 3:
                continue

            match = patt.match(splitted[2])     # third field contains IP
            if match and splitted[1] in ('S', 'E'):
                data[match.group('ip')] = True if splitted[1] == 'S' else False

        return data

    def prepare(self):
        all_domains = self._get_domain_ips()
        self.main_ip = self._find_main_ip(all_domains)
        if not all_domains or not self.main_ip:
            self.first_domain = None
            self.additional = {}
            return
        shared_ips = sorted(all_domains.get(self.main_ip, tuple()))
        self.first_domain = shared_ips[0] if shared_ips else None
        self.additional = {k: v for k, v in all_domains.items()
                           if k != self.main_ip}


class DirectAdmin(Panel):

    detect_path = '/usr/local/directadmin/custombuild/build'
    glob_path = '/usr/local/directadmin/data/users/*/domains/*.conf'

    @classmethod
    def _get_paths(cls):
        paths = []
        for path in glob.iglob(cls.glob_path):
            paths.append(path)
        return paths

    @staticmethod
    def _read_config(path):
        domain, ip = None, None
        domain_found, ip_found = False, False
        with open(path) as f:
            for line in f:
                if domain_found and ip_found:
                    break
                if line.startswith('#'):
                    continue
                if '=' not in line:
                    continue
                key, value = [i.strip() for i in line.split('=', 1)]
                if key == 'domain':
                    domain = value
                    domain_found = True
                elif key == 'ip':
                    ip = value
                    ip_found = True
                else:
                    continue
        return ip, domain

    @staticmethod
    def _find_main_ip(ip_map):
        """
        The IP address with maximum domains is the main one
        """
        max_count = 0
        max_ip = None
        for ip, domains in ip_map.items():
            count = len(domains)
            if count > max_count:
                max_count = count
                max_ip = ip
        return max_ip

    @classmethod
    def _get_domains(cls):
        domains = {}
        for path in cls._get_paths():
            try:
                ip, domain = cls._read_config(path)
            except UnicodeDecodeError:
                continue
            if ip and domain:
                if ip not in domains:
                    domains[ip] = []
                domains[ip].append(domain)
        return domains

    def prepare(self):
        all_domains = self._get_domains()
        self.main_ip = self._find_main_ip(all_domains)
        if not all_domains or not self.main_ip:
            self.first_domain = None
            self.additional = {}
            return
        shared_ips = sorted(all_domains.get(self.main_ip, tuple()))
        self.first_domain = shared_ips[0] if shared_ips else None
        self.additional = {k: v for k, v in all_domains.items()
                           if k != self.main_ip}


class AddressHandler:

    map_conf = '/etc/imunify360-webshield/backend-destinations.conf'
    map_file = '/etc/imunify360-webshield/default-destinations.dat'

    @staticmethod
    def _generate(length=8):
        sample = string.ascii_letters + string.digits
        return ''.join(random.sample(sample, length))

    @staticmethod
    def _get_panel():
        for panel in cPanel, Plesk, DirectAdmin:
            if panel.detect():
                return panel

    @staticmethod
    def _get_ip_addresses():
        addresses = set()
        patt = re.compile(
            r"""(?:\d+:\s?)?    # number (e.g. '1:') and optional space
                (?P<if>\S+)     # interface name (e.g. 'eth0')
                    \s+?        # space(s)
                inet6?\s        # word 'inet' or 'inet6'
                (?P<ip>(?:      # start IP capturing
                    \d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}  # for IPv4
                        |                               # or
                    [0-9a-fA-F:]+)                      # for IPv6
                )                                       # end capturing
                (?:/(?P<mask>\d{1,3}))?     # capture mask (e.g.'/24'), if any
                """, re.VERBOSE)
        p = subprocess.Popen(['ip', '-o', 'address', 'show'],
                             stdout=subprocess.PIPE,
                             stderr=subprocess.PIPE,
                             universal_newlines=True)
        out, err = p.communicate()
        if not out:
            return
        for line in out.splitlines():
            m = patt.match(line)
            if not m:
                continue
            iface, ip, mask = m.group('if', 'ip', 'mask')
            if iface == 'lo':
                continue
            if ':' in ip and ipaddress.IPv6Address(ip).is_link_local:
                continue
            addresses.add(ip)
        return addresses

    @classmethod
    def _save(cls, data, path, semicolon=True):
        if not data:
            return
        fmt = "{} {};\n" if semicolon else "{} {}\n"
        tmp_path = '.'.join([path, cls._generate()])
        with open(tmp_path, 'w') as f:
            for key, val in data.items():
                f.write(fmt.format(key, val))
        shutil.move(tmp_path, path)

    @classmethod
    def run(cls):
        addresses = cls._get_ip_addresses()

        if len(addresses) < 2:
            sys.stderr.write('No additional IP addresses found\n')
            return

        panel = cls._get_panel()
        if panel is None:
            sys.stderr.write('We cannot use unknown hosting panels. Skip\n')
            return

        p = panel(addresses)
        p.prepare()
        cls._save(p.get_ssl_mapping(), cls.map_file, False)


if __name__ == '__main__':
    AddressHandler.run()