import asyncio
import logging

try:
    from mock import Mock
except ImportError:
    from unittest.mock import Mock

import re
import ssl
import sys
import tqdm
from typing import Tuple, Optional, Dict, List
from urllib.parse import quote

import aiodns
import tqdm.asyncio
from python_socks import _errors as proxy_errors
from socid_extractor import extract
from aiohttp import TCPConnector, ClientSession, http_exceptions
from aiohttp.client_exceptions import ServerDisconnectedError, ClientConnectorError

from .activation import ParsingActivator, import_aiohttp_cookies
from . import errors
from .errors import CheckError
from .executors import (
    AsyncExecutor,
    AsyncioSimpleExecutor,
    AsyncioProgressbarQueueExecutor,
)

from .result import QueryResult, QueryStatus
from .sites import MaigretDatabase, MaigretSite
from .types import QueryOptions, QueryResultWrapper
from .utils import get_random_user_agent, ascii_data_display


SUPPORTED_IDS = (
    "username",
    "yandex_public_id",
    "gaia_id",
    "vk_id",
    "ok_id",
    "wikimapia_uid",
    "steam_id",
    "uidme_uguid",
    "yelp_userid",
)

BAD_CHARS = "#"


class CheckerBase:
    pass


class SimpleAiohttpChecker(CheckerBase):
    def __init__(self, *args, **kwargs):
        proxy = kwargs.get('proxy')
        cookie_jar = kwargs.get('cookie_jar')
        self.logger = kwargs.get('logger', Mock())

        # moved here to speed up the launch of Maigret
        from aiohttp_socks import ProxyConnector

        # make http client session
        connector = ProxyConnector.from_url(proxy) if proxy else TCPConnector(ssl=False)
        connector.verify_ssl = False
        self.session = ClientSession(
            connector=connector, trust_env=True, cookie_jar=cookie_jar
        )

    def prepare(self, url, headers=None, allow_redirects=True, timeout=0, method='get'):
        if method == 'get':
            request_method = self.session.get
        else:
            request_method = self.session.head

        future = request_method(
            url=url,
            headers=headers,
            allow_redirects=allow_redirects,
            timeout=timeout,
        )

        return future

    async def close(self):
        await self.session.close()

    async def check(self, future) -> Tuple[str, int, Optional[CheckError]]:
        html_text = None
        status_code = 0
        error: Optional[CheckError] = CheckError("Unknown")

        try:
            response = await future

            status_code = response.status
            response_content = await response.content.read()
            charset = response.charset or "utf-8"
            decoded_content = response_content.decode(charset, "ignore")
            html_text = decoded_content

            error = None
            if status_code == 0:
                error = CheckError("Connection lost")

            self.logger.debug(html_text)

        except asyncio.TimeoutError as e:
            error = CheckError("Request timeout", str(e))
        except ClientConnectorError as e:
            error = CheckError("Connecting failure", str(e))
        except ServerDisconnectedError as e:
            error = CheckError("Server disconnected", str(e))
        except http_exceptions.BadHttpMessage as e:
            error = CheckError("HTTP", str(e))
        except proxy_errors.ProxyError as e:
            error = CheckError("Proxy", str(e))
        except KeyboardInterrupt:
            error = CheckError("Interrupted")
        except Exception as e:
            # python-specific exceptions
            if sys.version_info.minor > 6 and (
                isinstance(e, ssl.SSLCertVerificationError)
                or isinstance(e, ssl.SSLError)
            ):
                error = CheckError("SSL", str(e))
            else:
                self.logger.debug(e, exc_info=True)
                error = CheckError("Unexpected", str(e))

        if error == "Invalid proxy response":
            self.logger.debug(e, exc_info=True)

        return str(html_text), status_code, error


class ProxiedAiohttpChecker(SimpleAiohttpChecker):
    def __init__(self, *args, **kwargs):
        proxy = kwargs.get('proxy')
        cookie_jar = kwargs.get('cookie_jar')
        self.logger = kwargs.get('logger', Mock())

        # moved here to speed up the launch of Maigret
        from aiohttp_socks import ProxyConnector

        connector = ProxyConnector.from_url(proxy)
        connector.verify_ssl = False
        self.session = ClientSession(
            connector=connector, trust_env=True, cookie_jar=cookie_jar
        )


class AiodnsDomainResolver(CheckerBase):
    def __init__(self, *args, **kwargs):
        loop = asyncio.get_event_loop()
        self.logger = kwargs.get('logger', Mock())
        self.resolver = aiodns.DNSResolver(loop=loop)

    def prepare(self, url, headers=None, allow_redirects=True, timeout=0, method='get'):
        return self.resolver.query(url, 'A')

    async def check(self, future) -> Tuple[str, int, Optional[CheckError]]:
        status = 404
        error = None
        text = ''

        try:
            res = await future
            text = str(res[0].host)
            status = 200
        except aiodns.error.DNSError:
            pass
        except Exception as e:
            self.logger.error(e, exc_info=True)
            error = CheckError('DNS resolve error', str(e))

        return text, status, error


class CheckerMock:
    def __init__(self, *args, **kwargs):
        pass

    def prepare(self, url, headers=None, allow_redirects=True, timeout=0, method='get'):
        return None

    async def check(self, future) -> Tuple[str, int, Optional[CheckError]]:
        await asyncio.sleep(0)
        return '', 0, None

    async def close(self):
        return


# TODO: move to separate class
def detect_error_page(
    html_text, status_code, fail_flags, ignore_403
) -> Optional[CheckError]:
    # Detect service restrictions such as a country restriction
    for flag, msg in fail_flags.items():
        if flag in html_text:
            return CheckError("Site-specific", msg)

    # Detect common restrictions such as provider censorship and bot protection
    err = errors.detect(html_text)
    if err:
        return err

    # Detect common site errors
    if status_code == 403 and not ignore_403:
        return CheckError("Access denied", "403 status code, use proxy/vpn")

    elif status_code >= 500:
        return CheckError("Server", f"{status_code} status code")

    return None


def debug_response_logging(url, html_text, status_code, check_error):
    with open("debug.log", "a") as f:
        status = status_code or "No response"
        f.write(f"url: {url}\nerror: {check_error}\nr: {status}\n")
        if html_text:
            f.write(f"code: {status}\nresponse: {str(html_text)}\n")


def process_site_result(
    response, query_notify, logger, results_info: QueryResultWrapper, site: MaigretSite
):
    if not response:
        return results_info

    fulltags = site.tags

    # Retrieve other site information again
    username = results_info["username"]
    is_parsing_enabled = results_info["parsing_enabled"]
    url = results_info.get("url_user")
    logger.info(url)

    status = results_info.get("status")
    if status is not None:
        # We have already determined the user doesn't exist here
        return results_info

    # Get the expected check type
    check_type = site.check_type

    # TODO: refactor
    if not response:
        logger.error(f"No response for {site.name}")
        return results_info

    html_text, status_code, check_error = response

    # TODO: add elapsed request time counting
    response_time = None

    if logger.level == logging.DEBUG:
        debug_response_logging(url, html_text, status_code, check_error)

    # additional check for errors
    if status_code and not check_error:
        check_error = detect_error_page(
            html_text, status_code, site.errors_dict, site.ignore403
        )

    # parsing activation
    is_need_activation = any(
        [s for s in site.activation.get("marks", []) if s in html_text]
    )

    if site.activation and html_text and is_need_activation:
        method = site.activation["method"]
        try:
            activate_fun = getattr(ParsingActivator(), method)
            # TODO: async call
            activate_fun(site, logger)
        except AttributeError:
            logger.warning(
                f"Activation method {method} for site {site.name} not found!"
            )
        except Exception as e:
            logger.warning(
                f"Failed activation {method} for site {site.name}: {str(e)}",
                exc_info=True,
            )
        # TODO: temporary check error

    site_name = site.pretty_name
    # presense flags
    # True by default
    presense_flags = site.presense_strs
    is_presense_detected = False

    if html_text:
        if not presense_flags:
            is_presense_detected = True
            site.stats["presense_flag"] = None
        else:
            for presense_flag in presense_flags:
                if presense_flag in html_text:
                    is_presense_detected = True
                    site.stats["presense_flag"] = presense_flag
                    logger.debug(presense_flag)
                    break

    def build_result(status, **kwargs):
        return QueryResult(
            username,
            site_name,
            url,
            status,
            query_time=response_time,
            tags=fulltags,
            **kwargs,
        )

    if check_error:
        logger.warning(check_error)
        result = QueryResult(
            username,
            site_name,
            url,
            QueryStatus.UNKNOWN,
            query_time=response_time,
            error=check_error,
            context=str(CheckError),
            tags=fulltags,
        )
    elif check_type == "message":
        # Checks if the error message is in the HTML
        is_absence_detected = any(
            [(absence_flag in html_text) for absence_flag in site.absence_strs]
        )
        if not is_absence_detected and is_presense_detected:
            result = build_result(QueryStatus.CLAIMED)
        else:
            result = build_result(QueryStatus.AVAILABLE)
    elif check_type in "status_code":
        # Checks if the status code of the response is 2XX
        if 200 <= status_code < 300:
            result = build_result(QueryStatus.CLAIMED)
        else:
            result = build_result(QueryStatus.AVAILABLE)
    elif check_type == "response_url":
        # For this detection method, we have turned off the redirect.
        # So, there is no need to check the response URL: it will always
        # match the request.  Instead, we will ensure that the response
        # code indicates that the request was successful (i.e. no 404, or
        # forward to some odd redirect).
        if 200 <= status_code < 300 and is_presense_detected:
            result = build_result(QueryStatus.CLAIMED)
        else:
            result = build_result(QueryStatus.AVAILABLE)
    else:
        # It should be impossible to ever get here...
        raise ValueError(
            f"Unknown check type '{check_type}' for " f"site '{site.name}'"
        )

    extracted_ids_data = {}

    if is_parsing_enabled and result.status == QueryStatus.CLAIMED:
        try:
            extracted_ids_data = extract(html_text)
        except Exception as e:
            logger.warning(f"Error while parsing {site.name}: {e}", exc_info=True)

        if extracted_ids_data:
            new_usernames = {}
            for k, v in extracted_ids_data.items():
                if "username" in k:
                    new_usernames[v] = "username"
                if k in SUPPORTED_IDS:
                    new_usernames[v] = k

            results_info["ids_usernames"] = new_usernames
            links = ascii_data_display(extracted_ids_data.get("links", "[]"))
            if "website" in extracted_ids_data:
                links.append(extracted_ids_data["website"])
            results_info["ids_links"] = links
            result.ids_data = extracted_ids_data

    # Save status of request
    results_info["status"] = result

    # Save results from request
    results_info["http_status"] = status_code
    results_info["is_similar"] = site.similar_search
    # results_site['response_text'] = html_text
    results_info["rank"] = site.alexa_rank
    return results_info


def make_site_result(
    site: MaigretSite, username: str, options: QueryOptions, logger
) -> QueryResultWrapper:
    results_site: QueryResultWrapper = {}

    # Record URL of main site and username
    results_site["site"] = site
    results_site["username"] = username
    results_site["parsing_enabled"] = options["parsing"]
    results_site["url_main"] = site.url_main
    results_site["cookies"] = (
        options.get("cookie_jar")
        and options["cookie_jar"].filter_cookies(site.url_main)
        or None
    )

    headers = {
        "User-Agent": get_random_user_agent(),
    }

    headers.update(site.headers)

    if "url" not in site.__dict__:
        logger.error("No URL for site %s", site.name)

    # URL of user on site (if it exists)
    url = site.url.format(
        urlMain=site.url_main, urlSubpath=site.url_subpath, username=quote(username)
    )

    # workaround to prevent slash errors
    url = re.sub("(?<!:)/+", "/", url)

    # always clearweb_checker for now
    checker = options["checkers"][site.protocol]

    # site check is disabled
    if site.disabled and not options['forced']:
        logger.debug(f"Site {site.name} is disabled, skipping...")
        results_site["status"] = QueryResult(
            username,
            site.name,
            url,
            QueryStatus.ILLEGAL,
            error=CheckError("Check is disabled"),
        )
    # current username type could not be applied
    elif site.type != options["id_type"]:
        results_site["status"] = QueryResult(
            username,
            site.name,
            url,
            QueryStatus.ILLEGAL,
            error=CheckError('Unsupported identifier type', f'Want "{site.type}"'),
        )
    # username is not allowed.
    elif site.regex_check and re.search(site.regex_check, username) is None:
        results_site["status"] = QueryResult(
            username,
            site.name,
            url,
            QueryStatus.ILLEGAL,
            error=CheckError(
                'Unsupported username format', f'Want "{site.regex_check}"'
            ),
        )
        results_site["url_user"] = ""
        results_site["http_status"] = ""
        results_site["response_text"] = ""
        # query_notify.update(results_site["status"])
    else:
        # URL of user on site (if it exists)
        results_site["url_user"] = url
        url_probe = site.url_probe
        if url_probe is None:
            # Probe URL is normal one seen by people out on the web.
            url_probe = url
        else:
            # There is a special URL for probing existence separate
            # from where the user profile normally can be found.
            url_probe = url_probe.format(
                urlMain=site.url_main,
                urlSubpath=site.url_subpath,
                username=username,
            )

        for k, v in site.get_params.items():
            url_probe += f"&{k}={v}"

        if site.check_type == "status_code" and site.request_head_only:
            # In most cases when we are detecting by status code,
            # it is not necessary to get the entire body:  we can
            # detect fine with just the HEAD response.
            request_method = 'head'
        else:
            # Either this detect method needs the content associated
            # with the GET response, or this specific website will
            # not respond properly unless we request the whole page.
            request_method = 'get'

        if site.check_type == "response_url":
            # Site forwards request to a different URL if username not
            # found.  Disallow the redirect so we can capture the
            # http status from the original URL request.
            allow_redirects = False
        else:
            # Allow whatever redirect that the site wants to do.
            # The final result of the request will be what is available.
            allow_redirects = True

        future = checker.prepare(
            method=request_method,
            url=url_probe,
            headers=headers,
            allow_redirects=allow_redirects,
            timeout=options['timeout'],
        )

        # Store future request object in the results object
        results_site["future"] = future
        results_site["checker"] = checker

    return results_site


async def check_site_for_username(
    site, username, options: QueryOptions, logger, query_notify, *args, **kwargs
) -> Tuple[str, QueryResultWrapper]:
    default_result = make_site_result(site, username, options, logger)
    future = default_result.get("future")
    if not future:
        return site.name, default_result

    checker = default_result["checker"]

    response = await checker.check(future=future)

    response_result = process_site_result(
        response, query_notify, logger, default_result, site
    )

    query_notify.update(response_result['status'], site.similar_search)

    return site.name, response_result


async def debug_ip_request(checker, logger):
    future = checker.prepare(url="https://icanhazip.com")
    ip, status, check_error = await checker.check(future)
    if ip:
        logger.debug(f"My IP is: {ip.strip()}")
    else:
        logger.debug(f"IP requesting {check_error.type}: {check_error.desc}")


def get_failed_sites(results: Dict[str, QueryResultWrapper]) -> List[str]:
    sites = []
    for sitename, r in results.items():
        status = r.get('status', {})
        if status and status.error:
            if errors.is_permanent(status.error.type):
                continue
            sites.append(sitename)
    return sites


async def maigret(
    username: str,
    site_dict: Dict[str, MaigretSite],
    logger,
    query_notify=None,
    proxy=None,
    tor_proxy=None,
    i2p_proxy=None,
    timeout=3,
    is_parsing_enabled=False,
    id_type="username",
    debug=False,
    forced=False,
    max_connections=100,
    no_progressbar=False,
    cookies=None,
    retries=0,
    check_domains=False,
) -> QueryResultWrapper:
    """Main search func

    Checks for existence of username on certain sites.

    Keyword Arguments:
    username               -- Username string will be used for search.
    site_dict              -- Dictionary containing sites data in MaigretSite objects.
    query_notify           -- Object with base type of QueryNotify().
                              This will be used to notify the caller about
                              query results.
    logger                 -- Standard Python logger object.
    timeout                -- Time in seconds to wait before timing out request.
                              Default is 3 seconds.
    is_parsing_enabled     -- Extract additional info from account pages.
    id_type                -- Type of username to search.
                              Default is 'username', see all supported here:
                              https://github.com/soxoj/maigret/wiki/Supported-identifier-types
    max_connections        -- Maximum number of concurrent connections allowed.
                              Default is 100.
    no_progressbar         -- Displaying of ASCII progressbar during scanner.
    cookies                -- Filename of a cookie jar file to use for each request.

    Return Value:
    Dictionary containing results from report. Key of dictionary is the name
    of the social network site, and the value is another dictionary with
    the following keys:
        url_main:      URL of main site.
        url_user:      URL of user on site (if account exists).
        status:        QueryResult() object indicating results of test for
                       account existence.
        http_status:   HTTP status code of query which checked for existence on
                       site.
        response_text: Text that came back from request.  May be None if
                       there was an HTTP error when checking for existence.
    """

    # notify caller that we are starting the query.
    if not query_notify:
        query_notify = Mock()

    query_notify.start(username, id_type)

    cookie_jar = None
    if cookies:
        logger.debug(f"Using cookies jar file {cookies}")
        cookie_jar = import_aiohttp_cookies(cookies)

    clearweb_checker = SimpleAiohttpChecker(
        proxy=proxy, cookie_jar=cookie_jar, logger=logger
    )

    # TODO
    tor_checker = CheckerMock()
    if tor_proxy:
        tor_checker = ProxiedAiohttpChecker(  # type: ignore
            proxy=tor_proxy, cookie_jar=cookie_jar, logger=logger
        )

    # TODO
    i2p_checker = CheckerMock()
    if i2p_proxy:
        i2p_checker = ProxiedAiohttpChecker(  # type: ignore
            proxy=i2p_proxy, cookie_jar=cookie_jar, logger=logger
        )

    # TODO
    dns_checker = CheckerMock()
    if check_domains:
        dns_checker = AiodnsDomainResolver(logger=logger)  # type: ignore

    if logger.level == logging.DEBUG:
        await debug_ip_request(clearweb_checker, logger)

    # setup parallel executor
    executor: Optional[AsyncExecutor] = None
    if no_progressbar:
        executor = AsyncioSimpleExecutor(logger=logger)
    else:
        executor = AsyncioProgressbarQueueExecutor(
            logger=logger, in_parallel=max_connections, timeout=timeout + 0.5
        )

    # make options objects for all the requests
    options: QueryOptions = {}
    options["cookies"] = cookie_jar
    options["checkers"] = {
        '': clearweb_checker,
        'tor': tor_checker,
        'dns': dns_checker,
        'i2p': i2p_checker,
    }
    options["parsing"] = is_parsing_enabled
    options["timeout"] = timeout
    options["id_type"] = id_type
    options["forced"] = forced

    # results from analysis of all sites
    all_results: Dict[str, QueryResultWrapper] = {}

    sites = list(site_dict.keys())

    attempts = retries + 1
    while attempts:
        tasks_dict = {}

        for sitename, site in site_dict.items():
            if sitename not in sites:
                continue
            default_result: QueryResultWrapper = {
                'site': site,
                'status': QueryResult(
                    username,
                    sitename,
                    '',
                    QueryStatus.UNKNOWN,
                    error=CheckError('Request failed'),
                ),
            }
            tasks_dict[sitename] = (
                check_site_for_username,
                [site, username, options, logger, query_notify],
                {'default': (sitename, default_result)},
            )

        cur_results = await executor.run(tasks_dict.values())

        # wait for executor timeout errors
        await asyncio.sleep(1)

        all_results.update(cur_results)

        sites = get_failed_sites(dict(cur_results))
        attempts -= 1

        if not sites:
            break

        if attempts:
            query_notify.warning(
                f'Restarting checks for {len(sites)} sites... ({attempts} attempts left)'
            )

    # closing http client session
    await clearweb_checker.close()
    if tor_proxy:
        await tor_checker.close()
    if i2p_proxy:
        await i2p_checker.close()

    # notify caller that all queries are finished
    query_notify.finish()

    return all_results


def timeout_check(value):
    """Check Timeout Argument.

    Checks timeout for validity.

    Keyword Arguments:
    value                  -- Time in seconds to wait before timing out request.

    Return Value:
    Floating point number representing the time (in seconds) that should be
    used for the timeout.

    NOTE:  Will raise an exception if the timeout in invalid.
    """
    from argparse import ArgumentTypeError

    try:
        timeout = float(value)
    except ValueError:
        raise ArgumentTypeError(f"Timeout '{value}' must be a number.")
    if timeout <= 0:
        raise ArgumentTypeError(f"Timeout '{value}' must be greater than 0.0s.")
    return timeout


async def site_self_check(
    site: MaigretSite,
    logger,
    semaphore,
    db: MaigretDatabase,
    silent=False,
    proxy=None,
    tor_proxy=None,
    i2p_proxy=None,
):
    changes = {
        "disabled": False,
    }

    check_data = [
        (site.username_claimed, QueryStatus.CLAIMED),
        (site.username_unclaimed, QueryStatus.AVAILABLE),
    ]

    logger.info(f"Checking {site.name}...")

    for username, status in check_data:
        async with semaphore:
            results_dict = await maigret(
                username=username,
                site_dict={site.name: site},
                logger=logger,
                timeout=30,
                id_type=site.type,
                forced=True,
                no_progressbar=True,
                retries=1,
                proxy=proxy,
                tor_proxy=tor_proxy,
                i2p_proxy=i2p_proxy,
            )

            # don't disable entries with other ids types
            # TODO: make normal checking
            if site.name not in results_dict:
                logger.info(results_dict)
                changes["disabled"] = True
                continue

            logger.debug(results_dict)

            result = results_dict[site.name]["status"]

        site_status = result.status

        if site_status != status:
            if site_status == QueryStatus.UNKNOWN:
                msgs = site.absence_strs
                etype = site.check_type
                logger.warning(
                    f"Error while searching {username} in {site.name}: {result.context}, {msgs}, type {etype}"
                )
                # don't disable in case of available username
                if status == QueryStatus.CLAIMED:
                    changes["disabled"] = True
            elif status == QueryStatus.CLAIMED:
                logger.warning(
                    f"Not found `{username}` in {site.name}, must be claimed"
                )
                logger.info(results_dict[site.name])
                changes["disabled"] = True
            else:
                logger.warning(f"Found `{username}` in {site.name}, must be available")
                logger.info(results_dict[site.name])
                changes["disabled"] = True

    logger.info(f"Site {site.name} checking is finished")

    if changes["disabled"] != site.disabled:
        site.disabled = changes["disabled"]
        db.update_site(site)
        if not silent:
            action = "Disabled" if site.disabled else "Enabled"
            print(f"{action} site {site.name}...")

    return changes


async def self_check(
    db: MaigretDatabase,
    site_data: dict,
    logger,
    silent=False,
    max_connections=10,
    proxy=None,
    tor_proxy=None,
    i2p_proxy=None,
) -> bool:
    sem = asyncio.Semaphore(max_connections)
    tasks = []
    all_sites = site_data

    def disabled_count(lst):
        return len(list(filter(lambda x: x.disabled, lst)))

    disabled_old_count = disabled_count(all_sites.values())

    for _, site in all_sites.items():
        check_coro = site_self_check(
            site, logger, sem, db, silent, proxy, tor_proxy, i2p_proxy
        )
        future = asyncio.ensure_future(check_coro)
        tasks.append(future)

    for f in tqdm.asyncio.tqdm.as_completed(tasks):
        await f

    disabled_new_count = disabled_count(all_sites.values())
    total_disabled = disabled_new_count - disabled_old_count

    if total_disabled >= 0:
        message = "Disabled"
    else:
        message = "Enabled"
        total_disabled *= -1

    if not silent:
        print(
            f"{message} {total_disabled} ({disabled_old_count} => {disabled_new_count}) checked sites. "
            "Run with `--info` flag to get more information"
        )

    return total_disabled != 0
