#
# Copyright (C) 2020-2021 Soleta Networks <info@soleta.eu>
#
# This program is free software: you can redistribute it and/or modify it under
# the terms of the GNU Affero General Public License as published by the
# Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.

import datetime
import hashlib
import logging
import os
import stat
import subprocess
import shlex
import shutil

from subprocess import Popen, PIPE

import fdisk

from src.ogClient import ogClient
from src.ogRest import ThreadState
from src.live.partcodes import GUID_MAP
from src.live.parttypes import get_parttype

from src.utils.legacy import *
from src.utils.net import ethtool
from src.utils.menu import generate_menu
from src.utils.fs import *
from src.utils.probe import os_probe, cache_probe
from src.utils.disk import *
from src.utils.cache import generate_cache_txt, umount_cache, init_cache
from src.utils.tiptorrent import *
from src.utils.sw_inventory import get_package_set
from src.utils.hw_inventory import get_hardware_inventory, legacy_list_hardware_inventory


OG_SHELL = '/bin/bash'

class OgLiveOperations:
    def __init__(self, config):
        self._url = config['opengnsys']['url']
        self._url_log = config['opengnsys']['url_log']
        self._smb_user = config['samba']['user']
        self._smb_pass = config['samba']['pass']

    def _restartBrowser(self, url):
        try:
            proc = subprocess.call(["pkill", "-9", "browser"])
            proc = subprocess.Popen(["browser", "-qws", url])
        except:
            logging.exception('Cannot restart browser')
            raise ValueError('Error: cannot restart browser')

    def _refresh_payload_disk(self, cxt, part_setup, num_disk):
        part_setup['disk'] = str(num_disk)
        part_setup['disk_type'] = 'DISK'
        part_setup['partition'] = '0'
        part_setup['filesystem'] = ''
        part_setup['os'] = ''
        part_setup['size'] = str(cxt.nsectors * cxt.sector_size // 1024)
        part_setup['used_size'] = '0'
        if not cxt.label:
            part_setup['code'] = '0'
        else:
            part_setup['code'] = '2' if cxt.label.name == 'gpt' else '1'

    def _refresh_payload_partition(self, cxt, pa, part_setup, disk):
        parttype = cxt.partition_to_string(pa, fdisk.FDISK_FIELD_TYPEID)
        fstype = cxt.partition_to_string(pa, fdisk.FDISK_FIELD_FSTYPE)
        padev = cxt.partition_to_string(pa, fdisk.FDISK_FIELD_DEVICE)
        size = cxt.partition_to_string(pa, fdisk.FDISK_FIELD_SIZE)
        partnum = pa.partno + 1
        source = padev
        target = padev.replace('dev', 'mnt')

        if cxt.label.name == 'gpt':
            code = GUID_MAP.get(parttype, 0x0)
        else:
            code = int(parttype, base=16)

        if mount_mkdir(source, target):
            probe_result = os_probe(target)
            part_setup['os'] = probe_result
            part_setup['used_size'] = get_usedperc(target)
            umount(target)
        else:
            part_setup['os'] = ''
            part_setup['used_size'] = '0'


        part_setup['disk_type'] = ''
        part_setup['partition'] = str(partnum)
        part_setup['filesystem'] = fstype.upper() if fstype else 'EMPTY'
        # part_setup['code'] = hex(code).removeprefix('0x')
        part_setup['code'] = hex(code)[2:]
        part_setup['size'] = str(int(size) // 1024)

        if (part_setup['filesystem'] == 'VFAT'):
            part_setup['filesystem'] = 'FAT32'

    def _refresh_part_setup_cache(self, cxt, pa, part_setup, cache):
        padev = cxt.partition_to_string(pa, fdisk.FDISK_FIELD_DEVICE)
        if padev == cache:
            part_setup['filesystem'] = 'CACHE'
            part_setup['code'] = 'ca'

    def _compute_md5(self, path, bs=2**20):
        m = hashlib.md5()
        with open(path, 'rb') as f:
            while True:
                buf = f.read(bs)
                if not buf:
                    break
                m.update(buf)
        return m.hexdigest()

    def _write_md5_file(self, path):
        if not os.path.exists(path):
            logging.error('Invalid path in _write_md5_file')
            raise ValueError('Invalid image path when computing md5 checksum')
        filename = path + ".full.sum"
        dig = self._compute_md5(path)
        try:
            with open(filename, 'w') as f:
                f.write(dig)
        except:
            logging.error(f'cannot write {filename}')
            return -1

        return 0

    def _copy_image_to_cache(self, image_name):
        """
        Copies /opt/opengnsys/image/{image_name} into
        /opt/opengnsys/cache/opt/opengnsys/images/

        Implies a unicast transfer. Does not use tiptorrent.
        """
        src = f'/opt/opengnsys/images/{image_name}.img'
        dst = f'/opt/opengnsys/cache/opt/opengnsys/images/{image_name}.img'
        try:
            r = shutil.copy(src, dst)
            tip_write_csum(image_name)
        except:
            logging.exception('Error copying image to cache')
            raise ValueError(f'Error: Cannot copy image {image_name} to cache')

    def _restore_image_unicast(self, repo, name, devpath, cache=False):
        if ogChangeRepo(repo, smb_user=self._smb_user, smb_pass=self._smb_pass) != 0:
            self._restartBrowser(self._url)
            logging.error('ogChangeRepo could not change repository to %s', repo)
            raise ValueError(f'Error: Cannot change repository to {repo}')
        logging.debug(f'restore_image_unicast: name => {name}')
        if cache:
            image_path = f'/opt/opengnsys/cache/opt/opengnsys/images/{name}.img'
            if (not os.path.exists(image_path) or
                not tip_check_csum(repo, name)):
                self._copy_image_to_cache(name)
        else:
            image_path = f'/opt/opengnsys/images/{name}.img'
        self._restore_image(image_path, devpath)

    def _restore_image_tiptorrent(self, repo, name, devpath):
        image_path = f'/opt/opengnsys/cache/opt/opengnsys/images/{name}.img'
        try:
            if (not os.path.exists(image_path) or
                not tip_check_csum(repo, name)):
                tip_client_get(repo, name)
        except:
            self._restartBrowser(self._url)
            if (not os.path.exists(image_path)):
                raise ValueError(f'Image file {image_path} does not exist')
            if (not tip_check_csum(repo, name)):
                raise ValueError(f'checksum file {name}.full.sum is missing in repository {repo}')

            raise ValueError(f'Unexpected error when restoring image file {image_path}')

        self._restore_image(image_path, devpath)

    def _restore_image(self, image_path, devpath):
        logging.debug(f'Restoring image at {image_path} into {devpath}')
        logging.debug(f'This process can take some time, please *DO NOT SHUT DOWN OR REBOOT* this client')
        cmd_lzop = shlex.split(f'lzop -dc {image_path}')
        cmd_pc = shlex.split(f'partclone.restore -d0 -C -I -o {devpath}')

        if not os.path.exists(image_path):
            logging.error('f{image_path} does not exist, exiting.')
            raise ValueError(f'Error: Image not found at {image_path}')

        with open('/tmp/command.log', 'wb', 0) as logfile:
            proc_lzop = subprocess.Popen(cmd_lzop,
                                         stdout=subprocess.PIPE)
            proc_pc = subprocess.Popen(cmd_pc,
                                       stdin=proc_lzop.stdout,
                                       stderr=logfile)
            proc_lzop.stdout.close()
            proc_pc.communicate()

    def _ogbrowser_clear_logs(self):
        logfiles = ['/tmp/command.log', '/tmp/session.log']
        for logfile in logfiles:
            with open(logfile, 'wb', 0) as f:
                f.truncate(0)

    def _poweroff_oglive(self, operation='poweroff'):
        interface = os.getenv('DEVICE')
        cmd_ethtool = shlex.split(f'ethtool -s {interface} wol g')
        cmd_browser = shlex.split('pkill -9 browser')
        if not shutil.which('busyboxOLD'):
            busybox = 'busybox'
        else:
            busybox = shutil.which('busyboxOLD')
        cmd_busybox = shlex.split(f'{busybox} {operation}')

        umount_all()
        umount_cache()
        if subprocess.run(cmd_ethtool).returncode != 0:
            logging.error('Error running ethtool subprocess')
        if subprocess.run(cmd_browser).returncode != 0:
            logging.error('Error terminating ogBrowser process')
        if subprocess.run(cmd_busybox) != 0:
            logging.error('Error running "busybox poweroff" subprocess')

    def poweroff(self):
        logging.info('Powering off client')
        self._poweroff_oglive()

    def reboot(self):
        logging.info('Rebooting client')
        self._poweroff_oglive(operation='reboot')

    def shellrun(self, request, ogRest):
        cmd = request.getrun()
        cmds = cmd.split(";|\n\r")

        self._restartBrowser(self._url_log)

        try:
            ogRest.proc = subprocess.Popen(cmds,
                               stdout=subprocess.PIPE,
                               shell=True,
                               executable=OG_SHELL)
            (output, error) = ogRest.proc.communicate()
        except:
            logging.exception('Exception when running "shell run" subprocess')
            raise ValueError('Error: Incorrect command value')

        if ogRest.proc.returncode != 0:
            logging.warn('Non zero exit code when running: %s', ' '.join(cmds))
        else:
            logging.info('Shell run command OK')

        self.refresh(ogRest)

        return output.decode('utf-8')

    def session(self, request, ogRest):
        disk = request.getDisk()
        partition = request.getPartition()
        cmd = f'{ogClient.OG_PATH}interfaceAdm/IniciarSesion {disk} {partition}'

        try:
            ogRest.proc = subprocess.Popen([cmd],
                               stdout=subprocess.PIPE,
                               shell=True,
                               executable=OG_SHELL)
            (output, error) = ogRest.proc.communicate()
        except:
            logging.exception('Exception when running session subprocess')
            raise ValueError('Error: Incorrect command value')

        logging.info('Starting OS at disk %s partition %s', disk, partition)
        return output.decode('utf-8')

    def software(self, request, ogRest):
        disk = request.getDisk()
        partition = request.getPartition()
        partdev = get_partition_device(int(disk), int(partition))
        mountpoint = partdev.replace('dev', 'mnt')
        if not mount_mkdir(partdev, mountpoint):
            raise RuntimeError(f'Error mounting {partdev} at {mountpoint}')
        if not os.path.ismount(mountpoint):
            raise RuntimeError('Invalid mountpoint for software inventory')

        self._restartBrowser(self._url_log)
        pkgset = get_package_set(mountpoint)
        self._restartBrowser(self._url)

        umount(mountpoint)
        logging.info('Software inventory command OK')

        # Software inventory result is still processed by legacy server code
        # (ogAdmServer.c).  Legacy response format is string where each
        # software package is separated by a newline '\n'.
        # Each package/software line follows this format:
        # "{package_name} {package_version}"
        return '\n'.join(map(str,pkgset))

    def hardware(self, ogRest):
        self._restartBrowser(self._url_log)
        logging.info('Running hardware inventory command')

        try:
            inventory = get_hardware_inventory()
        except ValueError as e:
            logging.exception('Error occurred while running get_hardware_inventory')
            raise e
        finally:
            self._restartBrowser(self._url)

        result = legacy_list_hardware_inventory(inventory)
        logging.info('Successful hardware inventory command execution')
        return result

    def setup(self, request, ogRest):
        table_type = request.getType()
        disk = request.getDisk()
        cache = request.getCache()
        cache_size = request.getCacheSize()
        partlist = request.getPartitionSetup()

        self._ogbrowser_clear_logs()
        self._restartBrowser(self._url_log)

        diskname = get_disks()[int(disk)-1]
        cxt = fdisk.Context(f'/dev/{diskname}',
                            details=True)

        if table_type == 'MSDOS':
            cxt.create_disklabel('dos')
        elif table_type == 'GPT':
            cxt.create_disklabel('gpt')
        else:
            logging.info(f'Unsupported partition layout: {table_type}, only MSDOS and GPT are supported')
            raise ValueError(f'Unsupported partition scheme {table_type}, only MSDOS and GPT are supported')

        logging.info(f'Setting up partition layout to {table_type}')

        for part in partlist:
            logging.info(f'Creating partition {part["partition"]} with {part["code"]} of {int(part["size"])//1024} Mbytes')
            if part["code"] == 'EMPTY':
                continue
            if ogRest.terminated:
                break
            if part["code"] == 'CACHE':
                umount_cache()

            pa = fdisk.Partition(start_follow_default=True,
                                 end_follow_default=False,
                                 partno_follow_default=False)
            parttype = get_parttype(cxt, part["code"])
            size = int(part["size"])
            pa.size = (size * (1 << 10)) // cxt.sector_size
            pa.partno = int(part["partition"]) - 1
            pa.type = parttype
            cxt.add_partition(pa)

        cxt.write_disklabel()
        subprocess.run(['partprobe', f'/dev/{diskname}'])

        for part in partlist:
            if part["filesystem"] == 'EMPTY':
                continue

            fs = part["filesystem"].lower()
            logging.info(f'Formatting partition {part["partition"]} with filesystem {part["filesystem"]}')

            partition = int(part["partition"])
            if fs == 'cache':
                mkfs('ext4', int(disk), partition, label='CACHE')
                init_cache()
            else:
                mkfs(fs, int(disk), partition)

        logging.info('Setup command OK')
        result = self.refresh(ogRest)

        self._restartBrowser(self._url)

        return result

    def image_restore(self, request, ogRest):
        disk = request.getDisk()
        partition = request.getPartition()
        name = request.getName()
        repo = request.getRepo()
        ctype = request.getType()
        profile = request.getProfile()
        cid = request.getId()
        partdev = get_partition_device(int(disk), int(partition))

        self._ogbrowser_clear_logs()
        self._restartBrowser(self._url_log)

        logging.debug('Image restore params:')
        logging.debug(f'\tname: {name}')
        logging.debug(f'\trepo: {repo}')
        logging.debug(f'\tprofile: {profile}')
        logging.debug(f'\tctype: {ctype}')

        if shutil.which('restoreImageCustom'):
            restoreImageCustom(repo, name, disk, partition, ctype)
        elif 'UNICAST' in ctype:
            cache = 'DIRECT' not in ctype
            self._restore_image_unicast(repo, name, partdev, cache)
        elif ctype == 'TIPTORRENT':
            self._restore_image_tiptorrent(repo, name, partdev)

        output = configureOs(disk, partition)

        self.refresh(ogRest)

        logging.info('Image restore command OK')
        return output

    def image_create(self, request, ogRest):
        disk = int(request.getDisk())
        partition = int(request.getPartition())
        name = request.getName()
        repo = request.getRepo()
        backup = request.getBackup()
        image_path = f'/opt/opengnsys/images/{name}.img'

        self._ogbrowser_clear_logs()
        self._restartBrowser(self._url_log)

        if ogChangeRepo(repo, smb_user=self._smb_user, smb_pass=self._smb_pass) != 0:
            self._restartBrowser(self._url)
            logging.error('ogChangeRepo could not change repository to %s', repo)
            raise ValueError(f'Error: Cannot change repository to {repo}')

        if ogRest.terminated:
            return

        try:
            diskname = get_disks()[disk-1]
            cxt = fdisk.Context(f'/dev/{diskname}', details=True)
            pa = None

            for i, p in enumerate(cxt.partitions):
                if (p.partno + 1) == partition:
                    pa = cxt.partitions[i]

            if pa is None:
                self._restartBrowser(self._url)
                logging.error(f'Target partition /dev/{diskname} not found')
                raise ValueError(f'Target partition /dev/{diskname} not found')

            padev = cxt.partition_to_string(pa, fdisk.FDISK_FIELD_DEVICE)
            fstype = cxt.partition_to_string(pa, fdisk.FDISK_FIELD_FSTYPE)
            if not fstype:
                logging.error(f'No filesystem detected in {padev}. Aborting image creation.')
                raise ValueError('Target partition has no filesystem present')

            if change_access(user=self._smb_user, pwd=self._smb_pass) == -1:
                logging.error('remount of /opt/opengnsys/images has failed')
                raise AssertionError('remount of /opt/opengnsys/images has failed')

            if os.access(f'/opt/opengnsys/images', os.R_OK | os.W_OK) == False:
                logging.error('Cannot access /opt/opengnsys/images in read and write mode, check permissions')
                raise ValueError('Cannot access image folder')

            if os.access(f'{image_path}', os.R_OK) == True:
                logging.info(f'image file {image_path} already exists, updating.')

            ogCopyEfiBootLoader(disk, partition)
            if ogReduceFs(disk, partition) == -1:
                logging.error(f'Failed to shrink {fstype} filesystem in {padev}')
                raise ValueError('Failed to shrink filesystem')

            cmd1 = shlex.split(f'partclone.{fstype} -I -C --clone -s {padev} -O -')
            cmd2 = shlex.split(f'lzop -1 -fo {image_path}')

            logfile = open('/tmp/command.log', 'wb', 0)

            if os.path.exists(image_path) and backup:
                shutil.move(image_path, f'{image_path}.ant')

            p1 = Popen(cmd1, stdout=PIPE, stderr=logfile)
            p2 = Popen(cmd2, stdin=p1.stdout)
            p1.stdout.close()

            logging.info(f'Creating image at {image_path} from {padev} using {fstype}')
            logging.info('*DO NOT REBOOT OR POWEROFF* the client during this time')

            try:
                retdata = p2.communicate()
            except OSError as e:
                logging.exception('Unexpected error when running partclone and lzop commands')
            finally:
                logfile.close()
                p2.terminate()
                p1.poll()

            logging.info(f'partclone process exited with code {p1.returncode}')
            logging.info(f'lzop process exited with code {p2.returncode}')

            ogExtendFs(disk, partition)

            if os.access(f'{image_path}', os.R_OK) == False:
                logging.error(f'Cannot access partclone image file {image_path}')
                raise ValueError('Cannot access image file')

            image_info = ogGetImageInfo(image_path)
        except:
            self._restartBrowser(self._url)
            logging.exception('Exception when running "image create" subprocess')
            raise ValueError(f'Error: Cannot create image for {fstype} filesystem in device {padev}')

        try:
            st = os.stat(image_path)
            size = st.st_size
            perms = st.st_mode & (stat.S_IRWXU | stat.S_IRWXG | stat.S_IRWXO)
            mtime = int(st.st_mtime)
        except:
            logging.info(f'cannot retrieve stats from {image_path}')
            size = 0
            perms = 0
            mtime = 0

        image_info.size = size
        image_info.perms = perms
        image_info.mtime = mtime

        if self._write_md5_file(f'/opt/opengnsys/images/{name}.img') == -1:
            logging.error(f'cannot write {name}.full.sum file')
            raise ValueError(f'Error: Cannot write {name}.full.sum file')

        self._restartBrowser(self._url)

        logging.info('Image creation command OK')
        return image_info

    def refresh(self, ogRest):
        self._restartBrowser(self._url_log)

        cache = cache_probe()
        disks = get_disks()
        interface = os.getenv('DEVICE')
        link = ethtool(interface)
        parsed = { 'serial_number': '',
                'disk_setup': [],
                'partition_setup': [],
                'link': link
        }

        for num_disk, disk in enumerate(get_disks(), start=1):
            logging.debug('refresh: processing %s', disk)
            part_setup = {}
            try:
                cxt = fdisk.Context(device=f'/dev/{disk}', details=True)
            except:
                continue

            self._refresh_payload_disk(cxt, part_setup, num_disk)
            parsed['disk_setup'].append(part_setup)

            for pa in cxt.partitions:
                part_setup = part_setup.copy()
                self._refresh_payload_partition(cxt, pa, part_setup, disk)
                self._refresh_part_setup_cache(cxt, pa, part_setup, cache)
                parsed['partition_setup'].append(part_setup)

        generate_menu(parsed['partition_setup'])
        generate_cache_txt()
        self._restartBrowser(self._url)

        logging.info('Sending response to refresh request')
        return parsed

    def probe(self, ogRest):

        interface = os.getenv('DEVICE')
        speed = ethtool(interface)

        return {'status': 'OPG' if ogRest.state != ThreadState.BUSY else 'BSY',
                'speed': speed}