# pylint: disable=wrong-import-position
from __future__ import print_function

import collections
import hmac
import json
import logging
import multiprocessing
import os
import random
import subprocess
import threading
import urllib2

import tornado
import tornado.concurrent
import tornado.gen
import tornado.ioloop
import tornado.iostream
from tornado.log import access_log
import tornado.process
import tornado.web
import tornado.websocket

from esphomeyaml import const
from esphomeyaml.__main__ import get_serial_ports
from esphomeyaml.helpers import run_system_command
from esphomeyaml.storage_json import StorageJSON, ext_storage_path
from esphomeyaml.util import shlex_quote

# pylint: disable=unused-import, wrong-import-order
from typing import Optional  # noqa

_LOGGER = logging.getLogger(__name__)
CONFIG_DIR = ''
PASSWORD = ''


# pylint: disable=abstract-method
class BaseHandler(tornado.web.RequestHandler):
    def is_authenticated(self):
        return not PASSWORD or self.get_secure_cookie('authenticated') == 'yes'


# pylint: disable=abstract-method, arguments-differ
class EsphomeyamlCommandWebSocket(tornado.websocket.WebSocketHandler):
    def __init__(self, application, request, **kwargs):
        super(EsphomeyamlCommandWebSocket, self).__init__(application, request, **kwargs)
        self.proc = None
        self.closed = False

    def on_message(self, message):
        if PASSWORD and self.get_secure_cookie('authenticated') != 'yes':
            return
        if self.proc is not None:
            return
        command = self.build_command(message)
        _LOGGER.info(u"Running command '%s'", ' '.join(shlex_quote(x) for x in command))
        self.proc = tornado.process.Subprocess(command,
                                               stdout=tornado.process.Subprocess.STREAM,
                                               stderr=subprocess.STDOUT)
        self.proc.set_exit_callback(self.proc_on_exit)
        tornado.ioloop.IOLoop.current().spawn_callback(self.redirect_stream)

    @tornado.gen.coroutine
    def redirect_stream(self):
        while True:
            try:
                data = yield self.proc.stdout.read_until_regex('[\n\r]')
            except tornado.iostream.StreamClosedError:
                break
            if data.endswith('\r') and random.randrange(100) < 90:
                continue
            try:
                data = data.replace('\033', '\\033')
            except UnicodeDecodeError:
                data = data.encode('ascii', 'backslashreplace')
            self.write_message({'event': 'line', 'data': data})

    def proc_on_exit(self, returncode):
        if not self.closed:
            _LOGGER.debug("Process exited with return code %s", returncode)
            self.write_message({'event': 'exit', 'code': returncode})

    def on_close(self):
        self.closed = True
        if self.proc is not None and self.proc.returncode is None:
            _LOGGER.debug("Terminating process")
            self.proc.proc.terminate()

    def build_command(self, message):
        raise NotImplementedError


class EsphomeyamlLogsHandler(EsphomeyamlCommandWebSocket):
    def build_command(self, message):
        js = json.loads(message)
        config_file = CONFIG_DIR + '/' + js['configuration']
        return ["esphomeyaml", config_file, "logs", '--serial-port', js["port"], '--escape']


class EsphomeyamlRunHandler(EsphomeyamlCommandWebSocket):
    def build_command(self, message):
        js = json.loads(message)
        config_file = os.path.join(CONFIG_DIR, js['configuration'])
        return ["esphomeyaml", config_file, "run", '--upload-port', js["port"],
                '--escape', '--use-esptoolpy']


class EsphomeyamlCompileHandler(EsphomeyamlCommandWebSocket):
    def build_command(self, message):
        js = json.loads(message)
        config_file = os.path.join(CONFIG_DIR, js['configuration'])
        return ["esphomeyaml", config_file, "compile"]


class EsphomeyamlValidateHandler(EsphomeyamlCommandWebSocket):
    def build_command(self, message):
        js = json.loads(message)
        config_file = os.path.join(CONFIG_DIR, js['configuration'])
        return ["esphomeyaml", config_file, "config"]


class EsphomeyamlCleanMqttHandler(EsphomeyamlCommandWebSocket):
    def build_command(self, message):
        js = json.loads(message)
        config_file = os.path.join(CONFIG_DIR, js['configuration'])
        return ["esphomeyaml", config_file, "clean-mqtt"]


class EsphomeyamlCleanHandler(EsphomeyamlCommandWebSocket):
    def build_command(self, message):
        js = json.loads(message)
        config_file = os.path.join(CONFIG_DIR, js['configuration'])
        return ["esphomeyaml", config_file, "clean"]


class EsphomeyamlHassConfigHandler(EsphomeyamlCommandWebSocket):
    def build_command(self, message):
        js = json.loads(message)
        config_file = os.path.join(CONFIG_DIR, js['configuration'])
        return ["esphomeyaml", config_file, "hass-config"]


class SerialPortRequestHandler(BaseHandler):
    def get(self):
        if not self.is_authenticated():
            self.redirect('/login')
            return
        ports = get_serial_ports()
        data = []
        for port, desc in ports:
            if port == '/dev/ttyAMA0':
                desc = 'UART pins on GPIO header'
            split_desc = desc.split(' - ')
            if len(split_desc) == 2 and split_desc[0] == split_desc[1]:
                # Some serial ports repeat their values
                desc = split_desc[0]
            data.append({'port': port, 'desc': desc})
        data.append({'port': 'OTA', 'desc': 'Over-The-Air'})
        self.write(json.dumps(sorted(data, reverse=True)))


class WizardRequestHandler(BaseHandler):
    def post(self):
        from esphomeyaml import wizard

        if not self.is_authenticated():
            self.redirect('/login')
            return
        kwargs = {k: ''.join(v) for k, v in self.request.arguments.iteritems()}
        destination = os.path.join(CONFIG_DIR, kwargs['name'] + '.yaml')
        wizard.wizard_write(path=destination, **kwargs)
        self.redirect('/?begin=True')


class DownloadBinaryRequestHandler(BaseHandler):
    def get(self):
        if not self.is_authenticated():
            self.redirect('/login')
            return

        configuration = self.get_argument('configuration')
        storage_path = ext_storage_path(CONFIG_DIR, configuration)
        storage_json = StorageJSON.load(storage_path)
        if storage_json is None:
            self.send_error()
            return

        path = storage_json.firmware_bin_path
        self.set_header('Content-Type', 'application/octet-stream')
        filename = '{}.bin'.format(storage_json.name)
        self.set_header("Content-Disposition", 'attachment; filename="{}"'.format(filename))
        with open(path, 'rb') as f:
            while 1:
                data = f.read(16384)  # or some other nice-sized chunk
                if not data:
                    break
                self.write(data)
        self.finish()


def _list_yaml_files():
    files = []
    for file in os.listdir(CONFIG_DIR):
        if not file.endswith('.yaml'):
            continue
        if file.startswith('.'):
            continue
        if file == 'secrets.yaml':
            continue
        files.append(file)
    files.sort()
    return files


def _list_dashboard_entries():
    files = _list_yaml_files()
    return [DashboardEntry(file) for file in files]


class DashboardEntry(object):
    def __init__(self, filename):
        self.filename = filename
        self._storage = None
        self._loaded_storage = False

    @property
    def full_path(self):  # type: () -> str
        return os.path.join(CONFIG_DIR, self.filename)

    @property
    def storage(self):  # type: () -> Optional[StorageJSON]
        if not self._loaded_storage:
            self._storage = StorageJSON.load(ext_storage_path(CONFIG_DIR, self.filename))
            self._loaded_storage = True
        return self._storage

    @property
    def address(self):
        if self.storage is None:
            return None
        return self.storage.address

    @property
    def name(self):
        if self.storage is None:
            return self.filename[:-len('.yaml')]
        return self.storage.name

    @property
    def esp_platform(self):
        if self.storage is None:
            return None
        return self.storage.esp_platform

    @property
    def board(self):
        if self.storage is None:
            return None
        return self.storage.board


class MainRequestHandler(BaseHandler):
    def get(self):
        if not self.is_authenticated():
            self.redirect('/login')
            return

        begin = bool(self.get_argument('begin', False))
        entries = _list_dashboard_entries()
        version = const.__version__
        docs_link = 'https://beta.esphomelib.com/esphomeyaml/' if 'b' in version else \
            'https://esphomelib.com/esphomeyaml/'
        mqtt_config = get_mqtt_config_lazy()

        self.render("templates/index.html", entries=entries,
                    version=version, begin=begin, docs_link=docs_link, mqtt_config=mqtt_config)


def _ping_func(filename, address):
    if os.name == 'nt':
        command = ['ping', '-n', '1', address]
    else:
        command = ['ping', '-c', '1', address]
    rc, _, _ = run_system_command(*command)
    return filename, rc == 0


class PingThread(threading.Thread):
    def run(self):
        pool = multiprocessing.Pool(processes=8)

        while not STOP_EVENT.is_set():
            # Only do pings if somebody has the dashboard open
            PING_REQUEST.wait()
            PING_REQUEST.clear()

            def callback(ret):
                PING_RESULT[ret[0]] = ret[1]

            entries = _list_dashboard_entries()
            queue = collections.deque()
            for entry in entries:
                if entry.address is None:
                    PING_RESULT[entry.filename] = None
                    continue

                result = pool.apply_async(_ping_func, (entry.filename, entry.address),
                                          callback=callback)
                queue.append(result)

            while queue:
                item = queue[0]
                if item.ready():
                    queue.popleft()
                    continue

                try:
                    item.get(0.1)
                except multiprocessing.TimeoutError:
                    pass

                if STOP_EVENT.is_set():
                    pool.terminate()
                    return


class PingRequestHandler(BaseHandler):
    def get(self):
        if not self.is_authenticated():
            self.redirect('/login')
            return

        PING_REQUEST.set()
        self.write(json.dumps(PING_RESULT))


PING_RESULT = {}  # type: dict
STOP_EVENT = threading.Event()
PING_REQUEST = threading.Event()


class LoginHandler(BaseHandler):
    def get(self):
        self.write('<html><body><form action="/login" method="post">'
                   'Password: <input type="password" name="password">'
                   '<input type="submit" value="Sign in">'
                   '</form></body></html>')

    def post(self):
        password = str(self.get_argument("password", ''))
        password = hmac.new(password).digest()
        if hmac.compare_digest(PASSWORD, password):
            self.set_secure_cookie("authenticated", "yes")
        self.redirect("/")


def make_app(debug=False):
    def log_function(handler):
        if handler.get_status() < 400:
            log_method = access_log.info

            if isinstance(handler, SerialPortRequestHandler) and not debug:
                return
            if isinstance(handler, PingRequestHandler) and not debug:
                return
        elif handler.get_status() < 500:
            log_method = access_log.warning
        else:
            log_method = access_log.error

        request_time = 1000.0 * handler.request.request_time()
        # pylint: disable=protected-access
        log_method("%d %s %.2fms", handler.get_status(),
                   handler._request_summary(), request_time)

    static_path = os.path.join(os.path.dirname(__file__), 'static')
    app = tornado.web.Application([
        (r"/", MainRequestHandler),
        (r"/login", LoginHandler),
        (r"/logs", EsphomeyamlLogsHandler),
        (r"/run", EsphomeyamlRunHandler),
        (r"/compile", EsphomeyamlCompileHandler),
        (r"/validate", EsphomeyamlValidateHandler),
        (r"/clean-mqtt", EsphomeyamlCleanMqttHandler),
        (r"/clean", EsphomeyamlCleanHandler),
        (r"/hass-config", EsphomeyamlHassConfigHandler),
        (r"/download.bin", DownloadBinaryRequestHandler),
        (r"/serial-ports", SerialPortRequestHandler),
        (r"/ping", PingRequestHandler),
        (r"/wizard.html", WizardRequestHandler),
        (r'/static/(.*)', tornado.web.StaticFileHandler, {'path': static_path}),
    ], debug=debug, cookie_secret=PASSWORD, log_function=log_function)
    return app


HASSIO_MQTT_CONFIG = None


def _get_mqtt_config_impl():
    token = os.getenv('HASSIO_TOKEN')
    if token is None:
        raise ValueError

    req = urllib2.Request('http://hassio/services/mqtt')
    req.add_header('X-HASSIO-KEY', token)
    resp = urllib2.urlopen(req)
    content = resp.read()
    mqtt_config = json.loads(content)
    return {
        'addon': mqtt_config['addon'],
        'host': mqtt_config['host'],
        'username': mqtt_config.get('username', ''),
        'password': mqtt_config.get('password', '')
    }


def get_mqtt_config_lazy():
    global HASSIO_MQTT_CONFIG

    if HASSIO_MQTT_CONFIG is None:
        return None

    if not HASSIO_MQTT_CONFIG:
        try:
            HASSIO_MQTT_CONFIG = _get_mqtt_config_impl()
        except Exception:  # pylint: disable=broad-except
            HASSIO_MQTT_CONFIG = None

    return HASSIO_MQTT_CONFIG


def start_web_server(args):
    global CONFIG_DIR
    global PASSWORD
    global HASSIO_MQTT_CONFIG

    CONFIG_DIR = args.configuration
    if not os.path.exists(CONFIG_DIR):
        os.makedirs(CONFIG_DIR)

    # HassIO options storage
    PASSWORD = args.password

    if args.hassio:
        HASSIO_MQTT_CONFIG = False

    if PASSWORD:
        PASSWORD = hmac.new(str(PASSWORD)).digest()
        # Use the digest of the password as our cookie secret. This makes sure the cookie
        # isn't too short. It, of course, enables local hash brute forcing (because the cookie
        # secret can be brute forced without making requests). But the hashing algorithm used
        # by tornado is apparently strong enough to make brute forcing even a short string pretty
        # hard.

    _LOGGER.info("Starting dashboard web server on port %s and configuration dir %s...",
                 args.port, CONFIG_DIR)
    app = make_app(args.verbose)
    app.listen(args.port)

    if args.open_ui:
        import webbrowser

        webbrowser.open('localhost:{}'.format(args.port))

    ping_thread = PingThread()
    ping_thread.start()
    try:
        tornado.ioloop.IOLoop.current().start()
    except KeyboardInterrupt:
        _LOGGER.info("Shutting down...")
        STOP_EVENT.set()
        PING_REQUEST.set()
        ping_thread.join()