#!/usr/bin/python3
"""install.py

- copy files from to_system into system directories
- set host name / network settings from aputools/servercfg file
"""

import os
import filecmp
import shutil
from glob import glob
from ipaddress import IPv4Interface
from configparser import ConfigParser
from os.path import join, getmtime, exists, basename

os.chdir('/root/aputools/to_system')

DEL = '__to_delete__'
CFGPATH = '/root/aputools/servercfg/%s_%6.6x.cfg'
TEMPLATE_CFG = """[NETWORK]
enp1s0=192.168.127.1/24
enp2s0=192.168.2.1/24
enp3s0=192.168.3.1/24
enp4s0=dhcp

[ROUTER]
3001=192.168.127.254:3001
"""


def write_when_new(filename, content, doit):
    if not content.endswith('\n'):
        content += '\n'
    with open(filename) as fil:
        old = fil.read()
    if old == content:
        return False
    if doit:
        with open(filename, 'w') as fil:
            fil.write(content)
    return True


def create_if(name, cfg, mac):
    result = dict(
        TYPE='Ethernet',
        NAME=name,
        DEVICE=name,
        BOOTPROTO='none',
        ONBOOT='yes',
        PROXY_METHOD='none',
        BROWSER_ONLY='no',
        IPV4_FAILURE_FATAL='yes',
        IPV6INIT='no')
    if cfg == 'off':
        result['ONBOOT']='no'
    elif cfg == 'dhcp':
        result['BOOTPROTO']='dhcp'
    else:
        interface = IPv4Interface(cfg)
        if '/' not in cfg:
            if interface < IPv4Interface('128.0.0.0'):
                cfg += '/8'
            elif interface < IPv4Interface('192.0.0.0'):
                cfg += '/16'
            else:
                cfg += '/24'
                interface = IPv4Interface(cfg)
        result['IPADDR'], result['NETMASK'] = interface.with_netmask.split('/')
        _, result['PREFIX'] = interface.with_prefixlen.split('/')
    return result


def walk(action):
    for dirpath, _, files in os.walk('.'):
        syspath = dirpath[1:]  # remove leading '.'
        action.dirpath = dirpath
        action.syspath = syspath
        if files:
            match, mismatch, missing = filecmp.cmpfiles(dirpath, syspath, files)
            if mismatch:
                newer = [f for f in mismatch if getmtime(join(syspath, f)) > getmtime(join(dirpath, f))]
                if newer:
                    action.newer(newer)
                if len(newer) < len(mismatch):
                    newer = set(newer)
                    action.older([f for f in mismatch if f not in newer])
            if missing:
                if DEL in missing:
                    missing.remove(DEL)
                    with open(join(dirpath, DEL)) as fil:
                        to_delete = []
                        for f in fil:
                            f = f.strip()
                            if f and exists(join(syspath, f)):
                                if exists(join(dirpath, f)):
                                    print('ERROR: %s in %s, but also in repo -> ignored' % (f, DEL))
                                else:
                                    to_delete.append(f)
                        action.delete(to_delete)
                if missing:
                    action.missing(missing)


class Show:
    dirty = False

    def show(self, title, files):
        self.dirty = True
        print('%s %s:\n  %s' % (title, self.syspath, ' '.join(files)))

    def newer(self, files):
        self.show('get from', files)

    def older(self, files):
        self.show('replace in', files)

    def missing(self, files):
        self.show('install in', files)

    def delete(self, files):
        self.show('remove from', files)


class Do:
    def newer(self, files):
        for file in files:
            shutil.copy(join(self.syspath, file), join(self.dirpath, file))

    def older(self, files):
        for file in files:
            shutil.copy(join(self.dirpath, file), join(self.syspath, file))

    def missing(self, files):
        self.older(files)

    def delete(self, files):
        for file in files:
            os.remove(join(self.syspath, file))


IFNAMES = ['enp%ds0' % i for i in range(1,5)]


def network(doit):
    netaddr_dict = {}
    for ifname in IFNAMES:
        with open('/sys/class/net/%s/address' % ifname) as f:
            netaddr_dict[ifname] = f.read().strip().lower()
    netaddr = netaddr_dict[IFNAMES[0]]
    apuid = int(''.join(netaddr.split(':')[-3:]), 16) & 0xfffffc
    cfgfile = None
    cfgfiles = []
    for i in range(4):
        # goodie: look for mac addresses of all 4 ports
        cfgfiles += glob(CFGPATH % ('*', apuid + i))
    with open('/etc/hostname') as f:
        hostname = f.read().strip()
    if not cfgfiles:
        print('no cfg file found for %s' % hostname)
        newname = input('enter host name: ')
        if not newname:
            print('no hostname given')
            return False
        cfgfile = CFGPATH % (newname, apuid)
        with open(cfgfile, 'w') as f:
            f.write(TEMPLATE_CFG)
    elif len(cfgfiles) > 1:
        print('ERROR: ambiguous cfg files: %s' % ', '.join(cfgfiles))
    else:
        cfgfile = cfgfiles[0]
    if cfgfile != CFGPATH % (hostname, apuid):
        if doit:
            os.system('sh ../sethostname.sh')
        else:
            if cfgfile:
                print('replace host name %r by %r' % (hostname, basename(cfgfile).rpartition('_')[0]))
                show.dirty = True
    if cfgfile is None:
        return False
    ifname = ''
    parser = ConfigParser()
    try:
        parser.read(cfgfile)
        network = dict(parser['NETWORK'])
        for ifname in IFNAMES:
            content = create_if(ifname, network.get(ifname, 'off'), netaddr_dict[ifname])
            content = '\n'.join('%s=%s' % kv for kv in content.items())
            todo = write_when_new('/etc/sysconfig/network-scripts/ifcfg-%s' % ifname, content, doit)
            if todo:
                print('change ', ifname)
                show.dirty = True
    except Exception as e:
        print('ERROR: can not handle %s %s: %r' % (hostname, ifname, e))
        return False
    return True


print('---')
show = Show()
result = network(False)
walk(show)

if not result:
    print('fix first above errors')
elif show.dirty:
    print('---')
    answer = input('do above? ')
    if answer.lower().startswith('y'):
        network(True)
        walk(Do())
else:
    print('nothing to do')