import binascii
import datetime
import hashlib
import json
import os
import re
import uuid
from functools import lru_cache
from logging import getLogger
from pathlib import Path
from typing import Dict, List

from defence360agent.contracts import sentry
from defence360agent.contracts.config import (
    ConfigFile,
    Core,
    CustomBillingConfig,
    Malware,
    MalwareSignatures,
    SystemConfig,
    int_from_envvar,
    FREEMIUM_FEATURE_FLAG,
)
from defence360agent.contracts.license import LicenseCLN
from defence360agent.contracts.messages import MessageType
from defence360agent.contracts.plugins import (
    MessageSink,
    MessageSource,
    expect,
)
from defence360agent.contracts.myimunify_id import get_myimunify_users
from defence360agent.feature_management.control import (
    is_native_feature_management_enabled,
    is_native_feature_management_supported,
)
from defence360agent.internals.iaid import IndependentAgentIDAPI
from defence360agent.subsys.panels.hosting_panel import HostingPanel
from defence360agent.subsys.panels.cpanel import cPanel

from defence360agent.utils import (
    log_error_and_ignore,
    recurring_check,
    Scope,
    stub_unexpected_error,
    safe_run,
    system_packages_info,
)

from defence360agent.utils.whmcs import WhmcsConf

#: info about these paths is sent to server in SERVER_CONFIG
CH_PATHS = (
    "/var/imunify360/imunify360.db",
    "/var/imunify360/imunify360.db-shm",
    "/var/imunify360/imunify360.db-wal",
)

logger = getLogger(__name__)

# Components which version sends to CH
PACKAGES_TO_REPORT = {
    "imunify360-firewall",
    "imunify-antivirus",
    "ai-bolit",
    "app-version-detector",
    "imunify360-php-i360",
    "imunify360-webshield-bundle",
    "imunify-realtime-av",
    "imunify-auditd-log-reader",
    "imunify360-pam",
    "imunify-notifier",
    "imunify360-unified-access-logger",
    "imunify360-ossec-server",
    "imunify-core",
    "imunify-ui",
    "imunify360-venv",
}


def read_cpu_info():
    with open("/proc/cpuinfo") as f:
        return f.read()


@lru_cache(maxsize=1)
def get_cpu_info():
    text = read_cpu_info()
    tuples = re.findall("^(.*?)[ \t]*:[ \t]*(.*)$", text, flags=re.M)

    res: List[dict] = []
    current = {}
    for key, value in tuples:
        if key == "processor":
            if current and "processor" in current:
                res.append(current)
                current = {}
        current[key] = value
    res.append(current)
    return res


@stub_unexpected_error
def get_cpu_cores():
    physical_ids = {}
    for processor in get_cpu_info():
        if (
            physical_id := processor.get("physical id", processor["processor"])
        ) not in physical_ids:
            physical_ids[physical_id] = int(processor.get("cpu cores", 1))
    return sum(physical_ids.values())


@stub_unexpected_error
def get_cpu_model_and_flags():
    processor = get_cpu_info()[0]
    return "{} {}".format(
        processor.get("model name") or processor["Processor"],
        processor.get("flags") or processor["Features"],
    )


@stub_unexpected_error
async def get_hosting_panel_version(hp):
    return await hp.version()


@stub_unexpected_error
async def get_users_amount(hp):
    return await hp.users_count()


@stub_unexpected_error
async def get_domains_amount(hp):
    return len(await hp.get_domain_to_owner())


@stub_unexpected_error
def get_malware_db_update_time():
    if os.path.exists(MalwareSignatures.AI_BOLIT_HOSTER):
        return int(os.path.getmtime(MalwareSignatures.AI_BOLIT_HOSTER))


@stub_unexpected_error
async def get_nfm_state():
    if await is_native_feature_management_supported():
        return await is_native_feature_management_enabled()


def get_sha256_machine_id():
    machine_id = Path("/etc/machine-id")
    if machine_id.exists():
        return hashlib.sha256(machine_id.read_bytes()).hexdigest()
    return None


@stub_unexpected_error
def get_myimunify_whmcs_activation_state():
    """
    True only if active in whmcs config
    otherwise False
    """
    activation_state = WhmcsConf().read().get("status")
    return activation_state == "active"


async def get_additional_info(hp):
    return {
        "cpu_cores": get_cpu_cores(),
        "cpuinfo": get_cpu_model_and_flags(),
        "hosting_panel_version": await get_hosting_panel_version(hp),
        "users_amount": await get_users_amount(hp),
        "domains_amount": await get_domains_amount(hp),
        "trim_malicious": Malware.CLEANUP_TRIM,
        "days_to_keep_backup": Malware.CLEANUP_KEEP,
        "malware_db_update_time": get_malware_db_update_time(),
        "native_feature_management_enabled": await get_nfm_state(),
        "machine_id": get_sha256_machine_id(),
        "myimunify_freemium_flag_exists": os.path.exists(
            FREEMIUM_FEATURE_FLAG
        ),
        "myimunify_whmcs_activated": get_myimunify_whmcs_activation_state(),
    }


async def get_users_configs(hp) -> Dict:
    """
    Return dict that includes users config values that are explicitly
    set in the corresponding config files.
    """
    result = dict()
    try:
        current_users = frozenset(await hp.get_users())
    except Exception:
        logger.exception("Failed to get the list of panel's users.")
        current_users = frozenset()
    users_conf = os.path.join("*", Core.USER_CONFIG_FILE_NAME)
    for userconf_file in Path(Core.USER_CONFDIR).glob(users_conf):
        if userconf_file.parent.name in current_users:
            result[userconf_file.parent.name] = ConfigFile(
                username=userconf_file.parent.name
            ).config_to_dict(normalize=False)
    return result


class SendServerConfig(MessageSink, MessageSource):
    """
    This plugin is to provide central server with
    different server metrics. Message is sent on plugin creation,
    and then every :period: seconds
    """

    SCOPE = Scope.AV

    def __init__(self, period=None):
        self._task = None
        # timestamp of the last ConfigUpdate sent to the server
        self._last_send_time = None  # avoid duplicate on startup
        if period:
            self._period = period
        else:
            self._period = int_from_envvar(
                "IMUNIFY360_SEND_SERVER_CONFIG_PERIOD",
                int(datetime.timedelta(days=1).total_seconds() / 3),
            )

    async def create_sink(self, loop):
        """MessageSink method"""

    @expect(MessageType.ConfigUpdate)
    @log_error_and_ignore()
    async def on_config_update_message(self, message):
        if self._last_send_time is None:  # 1st ConfigUpdate
            # enable sending config on 2nd+ ConfigUpdate
            self._last_send_time = 0
            return
        if not isinstance(message["conf"], SystemConfig):
            # ignore user configs, we do not need to send them on each change
            # all user configs will be send in
            # recurring_check(self._period)(self._send_server_config)()
            return

        if message["conf"].modified_since(self._last_send_time):
            self._last_send_time = message["timestamp"]
            self._loop.create_task(self._send_server_config())

    async def create_source(self, loop, sink):
        self._loop = loop
        self._sink = sink

        self._task = self._loop.create_task(
            recurring_check(self._period)(self._send_server_config)()
        )

    async def shutdown(self):
        if self._task is not None:
            self._task, t = None, self._task
            t.cancel()
            await t

    async def _create_server_config_msg(self):
        msg = MessageType.ServerConfig(uname=_uname_info())
        diskstat = _diskstat()
        if diskstat:
            msg["diskstats"] = diskstat
        hp = HostingPanel()

        msg.update(sentry.tags())
        msg.update(await get_additional_info(hp))
        if hp.NAME == cPanel.NAME:
            msg["users"] = await get_myimunify_users()
        msg["iaid"] = IndependentAgentIDAPI.get_iaid()
        msg["status_license"] = LicenseCLN.is_valid()
        msg["system_info"] = {
            "uptime_since": await _uptime(),
            "devices": await _blkid(),
            "mac": await _mac_address(),
        }
        msg["agent_global_config"] = (
            ConfigFile().config_to_dict()
            | CustomBillingConfig().config_to_dict()
        )
        msg["agent_users_configs"] = await get_users_configs(hp)
        msg["paths"] = await _get_path_sizes(CH_PATHS)
        msg["components_versions"] = await system_packages_info(
            PACKAGES_TO_REPORT
        )
        return msg

    async def _send_server_config(self):
        await self._sink.process_message(
            await self._create_server_config_msg()
        )


async def _get_path_sizes(paths) -> Dict[str, int]:
    """Return path->size mapping for *paths*.

    Send -errno on error.
    """
    sizes = {}
    for path in map(os.fspath, paths):
        try:
            size = os.path.getsize(path)
        except OSError as e:
            logger.warning("Can't get size for %s, reason: %s", path, e)
            sizes[path] = -e.errno
        else:
            sizes[path] = size
    return sizes


def _diskstat():
    try:
        with open("/proc/diskstats") as f:
            return f.read()
    except OSError as e:  # pragma: no cover
        logger.warning("Can't get diskstat: %s", str(e))


def _uname_info() -> dict:
    return dict(
        zip(
            ("sysname", "nodename", "release", "version", "machine"),
            os.uname(),
        )
    )


async def _uptime() -> str:
    """System up since"""
    return await safe_run(["uptime", "--since"])


async def _blkid() -> str:
    """Executes utility to locate/print block device attributes"""
    return await safe_run(["blkid"])


async def _mac_address() -> str:
    """MAC address in formatted way, like it specifies in
    /sys/class/net/*/address"""
    return binascii.hexlify(uuid.getnode().to_bytes(6, "big"), ":").decode()