# -*- coding: utf-8 -*-
# Copyright © Cloud Linux GmbH & Cloud Linux Software, Inc 2010-2018 All Rights Reserved
#
# Licensed under CLOUD LINUX LICENSE AGREEMENT
# http://cloudlinux.com/docs/LICENSE.TXT
#

import argparse
import hashlib
import json
import os
import re
import subprocess
import logging

import urllib.parse
import raven

from clcommon.public_hooks import (
    POST_MODIFY_DOMAIN,
    PRE_MODIFY_USER,
    POST_MODIFY_USER
)
from clcommon.public_hooks.lib.helpers import valid_name
from clcommon.utils import run_command, ExternalProgramFailed, is_user_present
from clcommon import cpapi
from secureio import makedirs_secure, write_file_secure, read_file_secure

EXIT_NO_USER_FOUND = 1
ERR_NO_USER_FOUND = 'Unable to find username in hook cmdline'
WHMAPI1 = '/usr/sbin/whmapi1'
LVE_DIR = '/var/lve'
TMP_DIR = os.path.join(LVE_DIR, 'tmp')

logger = logging.getLogger(__name__)

# Domain validation: RFC-1035 hostname-style (letters, digits, dot, hyphen).
# Use re.fullmatch at call-sites — the prior `^...$` form would have allowed
# a trailing newline (Python `$` matches end-of-string OR just before a final
# `\n`). bugbot 0bcbadf9 on !27 flagged this for the username regex; we apply
# the same fullmatch discipline here to domains. Username validation routes
# through valid_name (which already uses fullmatch).
#
# RFC 1035 hostname shape: each label starts with an alphanumeric, may
# contain interior `-`, ends with an alphanumeric, ≤63 chars per label,
# labels joined by literal `.`. Rejects bare `.`, `..`, `---`, leading/
# trailing dots and hyphens (bugbot 5a4f0354 on d1cc213). Mirrors the
# regex already in post_modify_domain.py — keeping the cpanel-bundle
# copy avoids a public-hooks-bin import from the cpanel bundle.
_VALID_DOMAIN_RE = re.compile(
    r'[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?'
    r'(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*'
)


def _is_valid_username(value):
    """Wrap the shared valid_name helper to fit the cpanel-hook return-0
    convention. valid_name raises argparse.ArgumentTypeError on bad input;
    cpanel hooks must return 0 (not sys.exit) so the cPanel hook chain
    keeps running for unrelated downstream listeners."""
    try:
        valid_name(value)
        return True
    except argparse.ArgumentTypeError:
        return False


def _is_valid_domain(value):
    """Domain-name validation matching the prior cpanel-bundle behavior but
    using fullmatch to defeat the trailing-newline bypass (bugbot 0bcbadf9)."""
    return isinstance(value, str) and bool(_VALID_DOMAIN_RE.fullmatch(value))


def print_response(hook_name, success=True):
    """
    cPanel expects that each custom hook
    prints two values in the end of the execution:
     - status, where 1 means success
     - message, which explains non-1 statuses
    otherwise nothing really breaks, but logs
    are full of "script returned invalid response" msgs
    :param hook_name: name, path or anything else to fill
                      message with in order to understand
                      what exactly failed
    :param success: is it everything ended successfully?
    :return: Nothing
    """
    if not success:
        print(0, f"Failed to execute hook {hook_name}; you can find logs in "
                 "/var/log/cloudlinux/hooks/info.log "
                 "and contact CloudLinux Support if you need "
                 "help with the issue.")
    else:
        print(1, "Ok")


# ATTENTION: we use this function in
# processpaneluserspackages and lvemanager
def call_sync_map():
    """
    Run lvectl sync-map and log possible stdout|err in case of errors.
    :return: None
    """
    with subprocess.Popen(
        ['lvectl', 'sync-map'],
        stdout=subprocess.PIPE,
        stderr=subprocess.PIPE,
        text=True,
    ) as proc:
        stdout, stderr = proc.communicate()
        if proc.returncode != 0:
            logger.error('Error during "lvectl sync-map", code: %s, '
                         'stderr: `%s`, stdout: `%s`. Reseller limits '
                         'kernel mapping might be not synchronized.'
                         'Contact CloudLinux Support for help.'
                         '', proc.returncode, stdout, stderr)


def cpanel_postwwwacct_main(data):
    """
    Post create account hook of cPanel
    :return: None
    """
    user = data.get('user', None)
    owner = data.get('owner', None)
    if not user:
        logger.warning(ERR_NO_USER_FOUND)
        return EXIT_NO_USER_FOUND
    return subprocess.call([
        POST_MODIFY_USER, 'create',
        '--username', user, '--owner', owner],
        env={'CPANEL_RESTORE': str(data.get('is_restore', 0))})


def cpanel_prekillacct_main(data):
    """
    Pre kill account hook of cPanel
    :return: None
    """
    #  It's necessary destroy lve before remove user home directory,
    # otherwise will be error due busy mount points of cagefs
    user = data.get('user', None)
    if not user:
        logger.warning(ERR_NO_USER_FOUND)
        return EXIT_NO_USER_FOUND

    if not is_user_present(user):
        logger.warning('User %s does not present in the system, skip hook', user)
        return 0

    return subprocess.call([
        PRE_MODIFY_USER, 'delete',
        '--username', user])


def cpanel_postkillacct_main(data):
    """
    Post kill account hook of cPanel
    :return: None
    """

    user = data.get('user', None)
    if not user:
        logger.warning(ERR_NO_USER_FOUND)
        return EXIT_NO_USER_FOUND

    return subprocess.call([
        POST_MODIFY_USER, 'delete',
        '--username', user])


def cpanel_postunsuspendacct_main(data):
    """
    Post unsuspend account hook of cPanel
    data: {'result': 1, 'args': {'user': 'susp2'}, 'user': 'root'}
    """
    user = data.get('args', {}).get('user', None)
    if not user:
        logger.warning(ERR_NO_USER_FOUND)
        return EXIT_NO_USER_FOUND

    if not is_user_present(user):
        logger.warning('User %s does not present in the system, skip hook', user)
        return 0

    return subprocess.call([
        POST_MODIFY_USER, 'unsuspend',
        '--username', user])


def cpanel_postsuspendacct_main(data):
    """
    Post unsuspend account hook of cPanel
    data: {'result': 1, 'args': {'user': 'susp2'}, 'user': 'root'}
    """
    user = data.get('args', {}).get('user', None)
    if not user:
        logger.warning(ERR_NO_USER_FOUND)
        return EXIT_NO_USER_FOUND

    if not is_user_present(user):
        logger.warning('User %s does not present in the system, skip hook', user)
        return 0

    return subprocess.call([
        POST_MODIFY_USER, 'suspend',
        '--username', user])


def _safe_tmp_path(user):
    """
    Build a safe file path under TMP_DIR for the given user.
    Raises ValueError if the resulting path escapes TMP_DIR.
    """
    if not user or os.sep in user or (os.altsep and os.altsep in user) or '..' in user:
        raise ValueError(f"Invalid user value: {user!r}")
    filename = os.path.join(TMP_DIR, user)
    real = os.path.realpath(filename)
    if not real.startswith(os.path.realpath(TMP_DIR) + os.sep):
        raise ValueError(f"Path traversal detected for user: {user!r}")
    return filename


def _read_old_domain(user):
    """
    Read old domain for modified account
    :param user: name of user
    :return: old domain
    :rtype: str
    """

    domain = None
    try:
        filename = _safe_tmp_path(user)
    except ValueError:
        logger.error("Invalid user for tmp file: %s", user)
        return None

    try:
        content = read_file_secure(filename, uid=0, gid=0, exit_on_error=False,
                                   # This log is intended to be used only by
                                   # cagefs update command
                                   write_log=False)
        domain = content[0]
    except (IndexError, OSError, IOError):
        # use Raven carefully and only in places where
        # you sure that sentry is already initialized
        raven.base.Raven.captureException(
            message='failed to read old domain for user (pre hook no called?)')

    return domain


def cpanel_postmodifyacct_main(data):
    """
    Post modify account hook of cPanel
    :return: None
    """
    user = data.get('user', None)
    new_user = data.get('newuser', None)
    domain = data.get('domain', None)
    exit_code = 0

    # changing owner of user
    # FIXME: this check does not work because cpanel sends `owner` always
    new_owner = data.get('owner', data.get('OWNER'))
    args = [POST_MODIFY_USER, 'modify', '-u', user]
    if new_owner:
        args += ['--new-owner', new_owner]
    if all((user, new_user,)) and user != new_user:
        args += ['--new-username', new_user]

    exit_code += subprocess.call(args)

    old_domain = _read_old_domain(user)
    if domain is not None and domain != old_domain:
        # looks like domain is renamed
        exit_code += subprocess.call([
            POST_MODIFY_DOMAIN,
            'modify', '--username', user if new_user is None else new_user,
            '--domain', old_domain, '--new-domain', domain,
            '--include-subdomains'])
    return exit_code


def cpanel_postrestoreacct_main(data):
    """
    Post restore account hook of cPanel
    :return: None
    """

    user = data.get('user', None)
    if not user:
        logger.warning(ERR_NO_USER_FOUND)
        return EXIT_NO_USER_FOUND
    return subprocess.call([
        POST_MODIFY_USER, 'restore',
        '--username', user])


def _get_old_domain(user):
    """
    Get old domain for modified account
    :param user: name of user
    :return: old domain
    :rtype: str
    """
    domain = None
    try:
        cmd = [
            WHMAPI1,
            'listaccts',
            f'search={user}',
            'searchtype=user',
            'searchmethod=exact',
            'want=domain',
            '--output=json'
        ]

        std_out = run_command(cmd, return_full_output=True)[1] # take only std_out, ignore std_err
        data = json.loads(std_out)

        domain = data['data']['acct'][0]['domain']
    except (ExternalProgramFailed, IndexError, KeyError):
        # use Raven carefully and only in places where
        # you sure that sentry is already initialized
        raven.base.Raven.captureException(message='failed to get old domain for user from cpanel')

    return domain


def cpanel_premodifyacct_main(data):
    """
    Pre modify account hook of cPanel
    :return: None
    """
    user = data.get('user')

    # getting old domain
    # TODO: why not cpapi?
    domain = _get_old_domain(user)
    if domain is None:
        return 0

    # save old domain to file
    try:
        filename = _safe_tmp_path(user)
    except ValueError:
        logger.error("Invalid user for tmp file: %s", user)
        return 0
    makedirs_secure(TMP_DIR, perm=0o750, uid=0, gid=0, parent_path=LVE_DIR)
    write_file_secure([domain], filename, uid=0, gid=0, perm=0o700)
    return 0


def cpanel_postcreateaddondom_main(data):
    args = data.get('args', {})
    user = data.get('user', None)
    newdomain = args.get('newdomain', None) or args.get('domain', None)
    if not all([user, newdomain]):
        logger.warning("Missing required arguments: user=%s, newdomain=%s",
                       str(user),
                       str(newdomain))
        return 0
    if not _is_valid_username(user):
        logger.warning("Invalid username value: %s", str(user))
        return 0
    if not _is_valid_domain(newdomain):
        logger.warning("Invalid domain value: %s", str(newdomain))
        return 0
    return subprocess.call(
        [
            POST_MODIFY_DOMAIN,
            'create', '--username', user,
            '--domain', newdomain]
    )


def cpanel_postkilladdondom_main(data):
    args = data.get('args', {})
    user = data.get('user', None)
    domain = args.get('domain', None)
    if not all([user, domain]):
        logger.warning("Missing required arguments: user=%s, domain=%s",
                       str(user),
                       str(domain))
        return 0
    if not _is_valid_username(user):
        logger.warning("Invalid username value: %s", str(user))
        return 0
    if not _is_valid_domain(domain):
        logger.warning("Invalid domain value: %s", str(domain))
        return 0
    return subprocess.call(
        [
            POST_MODIFY_DOMAIN,
            'delete', '--username', user,
            '--domain', domain]
    )


def cpanel_prechangesubdomaindocroot_main(data):
    """
    Pre change subdomain document root hook of cPanel
    Called when subdomain document root is being changed via
    Api2::SubDomain::changedocroot
    Saves old docroot to file for post hook to use
    :param data: hook data from cPanel
    :return: exit code
    """
    args = data.get('args', {})
    user = data.get('user', None)
    subdomain = args.get('subdomain', None)
    rootdomain = args.get('rootdomain', None)
    new_dir = args.get('dir', None)

    if not all([user, subdomain, rootdomain, new_dir]):
        logger.error("Missing required arguments: user=%s, subdomain=%s, rootdomain=%s, new_dir=%s",
                     str(user),
                     str(subdomain),
                     str(rootdomain),
                     str(new_dir))
        return 0

    # Construct full domain name (subdomain.rootdomain)
    domain = f"{subdomain}.{rootdomain}"

    # Get old docroot using cpapi
    try:
        old_docroot, _ = cpapi.docroot(domain)
    except Exception:
        raven.base.Raven.captureException(
            message=f'failed to get old docroot for subdomain {domain}')
        logger.warning("Could not get old docroot for domain %s", domain)
        return 0

    # Save old docroot and new dir to file for post hook
    # Use a hash suffix to avoid TOCTOU races with concurrent changes
    docroot_tmp_dir = os.path.join(TMP_DIR, 'prechangesubdomaindoc')
    suffix = hashlib.md5(f"{user}:{new_dir}".encode()).hexdigest()[:8]
    filename = os.path.join(docroot_tmp_dir, f"{domain}.{suffix}")

    if not os.path.realpath(filename).startswith(os.path.realpath(docroot_tmp_dir) + os.sep):
        logger.error("Invalid domain name %s: path traversal detected", domain)
        return 0

    if not os.path.realpath(filename).startswith(os.path.realpath(docroot_tmp_dir) + os.sep):
        logger.error("Invalid domain name %s: path traversal detected", domain)
        return 0

    makedirs_secure(TMP_DIR, perm=0o750, uid=0, gid=0, parent_path=LVE_DIR)
    makedirs_secure(docroot_tmp_dir, perm=0o750, uid=0, gid=0, parent_path=TMP_DIR)

    write_file_secure([old_docroot], filename, uid=0, gid=0, perm=0o700)

    return 0


def _read_old_docroot(domain, suffix):
    """
    Read saved docroot data for a subdomain
    """
    docroot_tmp_dir = os.path.join(TMP_DIR, 'prechangesubdomaindoc')
    filename = os.path.join(docroot_tmp_dir, f"{domain}.{suffix}")

    if not os.path.realpath(filename).startswith(os.path.realpath(docroot_tmp_dir) + os.sep):
        logger.error("Invalid domain name %s: path traversal detected", domain)
        return None

    if not os.path.realpath(filename).startswith(os.path.realpath(docroot_tmp_dir) + os.sep):
        logger.error("Invalid domain name %s: path traversal detected", domain)
        return None

    try:
        content = read_file_secure(filename, uid=0, gid=0, exit_on_error=False,
                                   write_log=False)
        old_docroot = content[0]
        return old_docroot
    except (IndexError, OSError, IOError):
        raven.base.Raven.captureException(
            message='failed to read old docroot for subdomain (pre hook not called?)')
        return None
    finally:
        try:
            os.unlink(filename)
        except OSError:
            pass


def cpanel_postchangesubdomaindocroot_main(data):
    """
    Post change subdomain document root hook of cPanel
    Called after subdomain document root is changed via
    Api2::SubDomain::changedocroot
    Reads saved docroot data and calls post_modify_domain
    :param data: hook data from cPanel
    :return: exit code
    """
    args = data.get('args', {})
    user = data.get('user', None)
    subdomain = args.get('subdomain', None)
    rootdomain = args.get('rootdomain', None)
    new_dir = args.get('dir', None)

    # new_dir must be in the all() check: the pre-hook only writes a temp
    # file when new_dir is present (line ~408 above), and the suffix is
    # md5(user + new_dir). If we computed suffix here with new_dir=None,
    # the literal string "None" would produce a suffix that does NOT match
    # any pre-hook file — _read_old_docroot would silently return None and
    # the pre-hook's temp file would leak. Fixes bugbot fbaa32bc on !28.
    if not all([user, subdomain, rootdomain, new_dir]):
        logger.warning("Missing required arguments: user=%s, subdomain=%s, rootdomain=%s, new_dir=%s",
                       str(user),
                       str(subdomain),
                       str(rootdomain),
                       str(new_dir))
        return 0

    # Construct full domain name (subdomain.rootdomain)
    domain = f"{subdomain}.{rootdomain}"

    suffix = hashlib.md5(f"{user}:{new_dir}".encode()).hexdigest()[:8]
    old_docroot = _read_old_docroot(domain, suffix)
    if old_docroot is None:
        logger.warning("Could not read old docroot for domain %s", domain)
        return 0

    # new_dir is guaranteed truthy by the all([...]) guard above.
    new_docroot = urllib.parse.unquote(new_dir)
    if '\0' in new_docroot or '..' in os.path.normpath(new_docroot).split(os.sep):
        logger.warning("Invalid new_docroot path for domain %s: %s",
                       domain, new_docroot)
        return 0

    cmd = [
        POST_MODIFY_DOMAIN,
        'modify', '--username', user,
        '--domain', domain,
        '--old-docroot', old_docroot,
        '--new-docroot', new_docroot,
    ]
    return subprocess.call(cmd)