#!/usr/bin/env python
# -*- coding: utf-8 -*-

# This file is part of Beremiz, a Integrated Development Environment for
# programming IEC 61131-3 automates supporting plcopen standard and CanFestival.
#
# Copyright (C) 2007: Edouard TISSERANT and Laurent BESSARD
# Copyright (C) 2017: Andrey Skvortsov
#
# See COPYING file for copyrights details.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.


import os
import sys
import getopt
import threading
import shlex
import traceback
import threading
from threading import Thread, Semaphore, Lock, current_thread
import builtins
from functools import partial

import runtime
from runtime.PyroServer import PyroServer
from runtime.xenomai import TryPreloadXenomai
from runtime import LogMessageAndException
from runtime import PlcStatus
from runtime import default_evaluator
from runtime.Stunnel import ensurePSK
import util.paths as paths

# In case system time is ajusted, it is better to use
# monotonic timers for timers and other timeout based operations.
# hot-patch threading module to force using monitonic time for all 
# Thread/Timer/Event/Condition

from runtime.monotonic_time import monotonic
threading._time = monotonic

try:
    from runtime.spawn_subprocess import Popen
except ImportError:
    from subprocess import Popen

def version():
    from version import app_version
    print("Beremiz_service: ", app_version)


def usage():
    version()
    print("""
Usage of Beremiz PLC execution service :\n
%s {[-n servicename] [-i IP] [-p port] [-x enabletaskbar] [-a autostart]|-h|--help} working_dir
  -n  service name (default:None, zeroconf discovery disabled)
  -i  IP address of interface to bind to (default:localhost)
  -p  port number default:3000
  -h  print this help text and quit
  -a  autostart PLC (0:disable 1:enable) (default:0)
  -x  enable/disable wxTaskbarIcon (0:disable 1:enable) (default:1)
  -t  enable/disable Twisted web interface (0:disable 1:enable) (default:1)
  -w  web server port or "off" to disable web server (default:8009)
  -c  WAMP client config file (can be overriden by wampconf.json in project)
  -s  PSK secret path (default:PSK disabled)
  -e  python extension (absolute path .py)

           working_dir - directory where are stored PLC files
""" % sys.argv[0])


try:
    opts, argv = getopt.getopt(sys.argv[1:], "i:p:n:x:t:a:w:c:e:s:h", ["help", "version", "status-change=", "on-plc-start=", "on-plc-stop="])
except getopt.GetoptError as err:
    # print help information and exit:
    print(str(err))  # will print something like "option -a not recognized"
    usage()
    sys.exit(2)

# default values
interface = ''
port = 3000
webport = 8009
PSKpath = None
wampconf = None
servicename = None
autostart = False
enablewx = True
havewx = False
enabletwisted = True
havetwisted = False

extensions = []
statuschange = []
def status_change_call_factory(wanted, args):
    def status_change_call(status):
        if wanted is None or status is wanted:
            cmd = shlex.split(args.format(status))
            Popen(cmd)
    return status_change_call

for o, a in opts:
    if o == "-h" or o == "--help":
        usage()
        sys.exit()
    if o == "--version":
        version()
        sys.exit()
    if o == "--on-plc-start":
        statuschange.append(status_change_call_factory(PlcStatus.Started, a))
    elif o == "--on-plc-stop":
        statuschange.append(status_change_call_factory(PlcStatus.Stopped, a))
    elif o == "--status-change":
        statuschange.append(status_change_call_factory(None, a))
    elif o == "-i":
        if len(a.split(".")) == 4:
            interface = a
        elif a == "localhost":
            interface = '127.0.0.1'
        else:
            usage()
            sys.exit()
    elif o == "-p":
        # port: port that the service runs on
        port = int(a)
    elif o == "-n":
        servicename = a
    elif o == "-x":
        enablewx = int(a)
    elif o == "-t":
        enabletwisted = int(a)
    elif o == "-a":
        autostart = int(a)
    elif o == "-w":
        webport = None if a == "off" else int(a)
    elif o == "-c":
        wampconf = None if a == "off" else a
    elif o == "-s":
        PSKpath = None if a == "off" else a
    elif o == "-e":
        fnameanddirname = list(os.path.split(os.path.realpath(a)))
        fnameanddirname.reverse()
        extensions.append(fnameanddirname)
    else:
        usage()
        sys.exit()


beremiz_dir = paths.AbsDir(__file__)

if len(argv) > 1:
    usage()
    sys.exit()
elif len(argv) == 1:
    WorkingDir = argv[0]
    os.chdir(WorkingDir)
elif len(argv) == 0:
    WorkingDir = os.getcwd()
    argv = [WorkingDir]

builtins.__dict__['_'] = lambda x: x
# TODO: add a cmdline parameter if Trying Preloading Xenomai makes problem
TryPreloadXenomai()
version()


def Bpath(*args):
    return os.path.join(beremiz_dir, *args)


import locale
# Matiec's standard library relies on libC's locale-dependent
# string to/from number convertions, but IEC-61131 counts
# on '.' for decimal point. Therefore locale is reset to "C" */
locale.setlocale(locale.LC_NUMERIC, "C")

def SetupI18n():
    # Get folder containing translation files
    localedir = os.path.join(beremiz_dir, "locale")
    # Get the default language
    langid = wx.LANGUAGE_DEFAULT
    # Define translation domain (name of translation files)
    domain = "Beremiz"

    # Define locale for wx
    loc = builtins.__dict__.get('loc', None)
    if loc is None:
        wx.LogGui.EnableLogging(False)
        loc = wx.Locale(langid)
        wx.LogGui.EnableLogging(True)
        builtins.__dict__['loc'] = loc
        # Define location for searching translation files
    loc.AddCatalogLookupPathPrefix(localedir)
    # Define locale domain
    loc.AddCatalog(domain)

    builtins.__dict__['_'] = wx.GetTranslation


# Life is hard... have a candy.
# pylint: disable=wrong-import-position,wrong-import-order
if enablewx:
    try:
        import wx
        havewx = True
    except ImportError:
        print("Wx unavailable !")
        havewx = False

    if havewx:
        import re
        import wx.adv

        app = wx.App(redirect=False)
        app.SetTopWindow(wx.Frame(None, -1))

        default_locale = None
        SetupI18n()

        defaulticon = wx.Image(Bpath("images", "brz.png"))
        starticon = wx.Image(Bpath("images", "icoplay24.png"))
        stopicon = wx.Image(Bpath("images", "icostop24.png"))

        class ParamsEntryDialog(wx.TextEntryDialog):

            def __init__(self, parent, message, caption=_("Please enter text"), defaultValue="",
                         style=wx.OK | wx.CANCEL | wx.CENTRE, pos=wx.DefaultPosition):
                wx.TextEntryDialog.__init__(self, parent, message, caption, defaultValue, style, pos)

                self.Tests = []
                self.Bind(wx.EVT_BUTTON, self.OnOK, id=self.GetAffirmativeId())

            def OnOK(self, event):
                value = self.GetValue()
                texts = {"value": value}
                for function, message in self.Tests:
                    if not function(value):
                        message = wx.MessageDialog(self, message % texts, _("Error"), wx.OK | wx.ICON_ERROR)
                        message.ShowModal()
                        message.Destroy()
                        return
                self.EndModal(wx.ID_OK)
                event.Skip()

            def GetValue(self):
                return self.GetSizer().GetItem(1).GetWindow().GetValue()

            def SetTests(self, tests):
                self.Tests = tests

        class BeremizTaskBarIcon(wx.adv.TaskBarIcon):
            TBMENU_START = wx.NewIdRef()
            TBMENU_STOP = wx.NewIdRef()
            TBMENU_CHANGE_NAME = wx.NewIdRef()
            TBMENU_CHANGE_PORT = wx.NewIdRef()
            TBMENU_CHANGE_INTERFACE = wx.NewIdRef()
            TBMENU_LIVE_SHELL = wx.NewIdRef()
            TBMENU_WXINSPECTOR = wx.NewIdRef()
            TBMENU_CHANGE_WD = wx.NewIdRef()
            TBMENU_QUIT = wx.NewIdRef()

            def __init__(self, pyroserver):
                wx.adv.TaskBarIcon.__init__(self)
                self.pyroserver = pyroserver
                # Set the image
                self.UpdateIcon(None)

                # bind some events
                self.Bind(wx.EVT_MENU, self.OnTaskBarStartPLC, id=self.TBMENU_START)
                self.Bind(wx.EVT_MENU, self.OnTaskBarStopPLC, id=self.TBMENU_STOP)
                self.Bind(wx.EVT_MENU, self.OnTaskBarChangeName, id=self.TBMENU_CHANGE_NAME)
                self.Bind(wx.EVT_MENU, self.OnTaskBarChangeInterface, id=self.TBMENU_CHANGE_INTERFACE)
                self.Bind(wx.EVT_MENU, self.OnTaskBarLiveShell, id=self.TBMENU_LIVE_SHELL)
                self.Bind(wx.EVT_MENU, self.OnTaskBarWXInspector, id=self.TBMENU_WXINSPECTOR)
                self.Bind(wx.EVT_MENU, self.OnTaskBarChangePort, id=self.TBMENU_CHANGE_PORT)
                self.Bind(wx.EVT_MENU, self.OnTaskBarChangeWorkingDir, id=self.TBMENU_CHANGE_WD)
                self.Bind(wx.EVT_MENU, self.OnTaskBarQuit, id=self.TBMENU_QUIT)

            def CreatePopupMenu(self):
                """
                This method is called by the base class when it needs to popup
                the menu for the default EVT_RIGHT_DOWN event.  Just create
                the menu how you want it and return it from this function,
                the base class takes care of the rest.
                """
                menu = wx.Menu()
                menu.Append(self.TBMENU_START, _("Start PLC"))
                menu.Append(self.TBMENU_STOP, _("Stop PLC"))
                menu.AppendSeparator()
                menu.Append(self.TBMENU_CHANGE_NAME, _("Change Name"))
                menu.Append(self.TBMENU_CHANGE_INTERFACE, _("Change IP of interface to bind"))
                menu.Append(self.TBMENU_CHANGE_PORT, _("Change Port Number"))
                menu.Append(self.TBMENU_CHANGE_WD, _("Change working directory"))
                menu.AppendSeparator()
                menu.Append(self.TBMENU_LIVE_SHELL, _("Launch a live Python shell"))
                menu.Append(self.TBMENU_WXINSPECTOR, _("Launch WX GUI inspector"))
                menu.AppendSeparator()
                menu.Append(self.TBMENU_QUIT, _("Quit"))
                return menu

            def MakeIcon(self, img):
                """
                The various platforms have different requirements for the
                icon size...
                """
                if "wxMSW" in wx.PlatformInfo:
                    img = img.Scale(16, 16)
                elif "wxGTK" in wx.PlatformInfo:
                    img = img.Scale(22, 22)
                # wxMac can be any size upto 128x128, so leave the source img alone....
                icon = wx.Icon(img.ConvertToBitmap())
                return icon

            def OnTaskBarStartPLC(self, evt):
                runtime.GetPLCObjectSingleton().StartPLC()

            def OnTaskBarStopPLC(self, evt):
                runtime.GetPLCObjectSingleton().StopPLC()

            def OnTaskBarChangeInterface(self, evt):
                ip_addr = self.pyroserver.ip_addr
                ip_addr = '' if ip_addr is None else ip_addr
                dlg = ParamsEntryDialog(None, _("Enter the IP of the interface to bind"), defaultValue=ip_addr)
                dlg.SetTests([(re.compile(r'\d{1,3}(?:\.\d{1,3}){3}$').match, _("IP is not valid!")),
                              (lambda x:len([x for x in x.split(".") if 0 <= int(x) <= 255]) == 4,
                               _("IP is not valid!"))])
                if dlg.ShowModal() == wx.ID_OK:
                    self.pyroserver.ip_addr = dlg.GetValue()
                    self.pyroserver.Restart()

            def OnTaskBarChangePort(self, evt):
                dlg = ParamsEntryDialog(None, _("Enter a port number "), defaultValue=str(self.pyroserver.port))
                dlg.SetTests([(str.isdigit, _("Port number must be an integer!")), (lambda port: 0 <= int(port) <= 65535, _("Port number must be 0 <= port <= 65535!"))])
                if dlg.ShowModal() == wx.ID_OK:
                    self.pyroserver.port = int(dlg.GetValue())
                    self.pyroserver.Restart()

            def OnTaskBarChangeWorkingDir(self, evt):
                dlg = wx.DirDialog(None, _("Choose a working directory "), self.pyroserver.workdir, wx.DD_NEW_DIR_BUTTON)
                if dlg.ShowModal() == wx.ID_OK:
                    self.pyroserver.workdir = dlg.GetPath()
                    self.pyroserver.Restart()

            def OnTaskBarChangeName(self, evt):
                _servicename = self.pyroserver.servicename
                _servicename = '' if _servicename is None else _servicename
                dlg = ParamsEntryDialog(None, _("Enter a name "), defaultValue=_servicename)
                dlg.SetTests([(lambda name: len(name) != 0, _("Name must not be null!"))])
                if dlg.ShowModal() == wx.ID_OK:
                    self.pyroserver.servicename = dlg.GetValue()
                    self.pyroserver.Restart()

            def _LiveShellLocals(self):
                return {"locals": runtime.GetPLCObjectSingleton().python_runtime_vars}

            def OnTaskBarLiveShell(self, evt):
                from wx import py
                frame = py.crust.CrustFrame(**self._LiveShellLocals())
                frame.Show()

            def OnTaskBarWXInspector(self, evt):
                # Activate the widget inspection tool
                from wx.lib.inspection import InspectionTool
                if not InspectionTool().initialized:
                    InspectionTool().Init(**self._LiveShellLocals())

                wnd = wx.GetApp()
                InspectionTool().Show(wnd, True)

            def OnTaskBarQuit(self, evt):
                if wx.Platform == '__WXMSW__':
                    Thread(target=self.pyroserver.Quit).start()
                self.RemoveIcon()
                wx.CallAfter(wx.GetApp().ExitMainLoop)

            def UpdateIcon(self, plcstatus):
                if plcstatus is PlcStatus.Started:
                    currenticon = self.MakeIcon(starticon)
                elif plcstatus is PlcStatus.Stopped:
                    currenticon = self.MakeIcon(stopicon)
                else:
                    currenticon = self.MakeIcon(defaulticon)
                self.SetIcon(currenticon, "Beremiz Service")


if not os.path.isdir(WorkingDir):
    os.mkdir(WorkingDir)


if enabletwisted:
    import warnings
    with warnings.catch_warnings():
        warnings.simplefilter("ignore")
        try:
            if havewx:
                from twisted.internet import wxreactor
                wxreactor.install()
                from twisted.internet import reactor
                reactor.registerWxApp(app)
            else:
                # from twisted.internet import pollreactor
                # pollreactor.install()
                from twisted.internet import reactor

            havetwisted = True
        except ImportError:
            print(_("Twisted unavailable."))
            havetwisted = False

pyruntimevars = {}

if havewx:
    wx_eval_lock = Semaphore(0)

    def statuschangeTskBar(status):
        wx.CallAfter(taskbar_instance.UpdateIcon, status)

    statuschange.append(statuschangeTskBar)

    def wx_evaluator(obj, *args, **kwargs):
        tocall, args, kwargs = obj.call
        obj.res = default_evaluator(tocall, *args, **kwargs)
        wx_eval_lock.release()

    main_thread_id = current_thread().ident
    def evaluator(tocall, *args, **kwargs):
        # To prevent deadlocks, check if current thread is not one already main
        current_id = current_thread().ident

        if main_thread_id != current_id:
            o = type('', (object,), dict(call=(tocall, args, kwargs), res=None))
            wx.CallAfter(wx_evaluator, o)
            wx_eval_lock.acquire()
            return o.res
        else:
            # avoid dead lock if called from main : do job immediately
            return default_evaluator(tocall, *args, **kwargs)
else:
    evaluator = default_evaluator

# Exception hooks


def LogException(*exp):
    LogMessageAndException("", exp)


sys.excepthook = LogException


def installThreadExcepthook():
    init_old = threading.Thread.__init__

    def init(self, *args, **kwargs):
        init_old(self, *args, **kwargs)
        run_old = self.run

        def run_with_except_hook(*args, **kw):
            try:
                run_old(*args, **kw)
            except (KeyboardInterrupt, SystemExit):
                raise
            except Exception:
                sys.excepthook(*sys.exc_info())
        self.run = run_with_except_hook
    threading.Thread.__init__ = init


installThreadExcepthook()
havewamp = False

if havetwisted:
    if webport is not None:
        try:
            import runtime.NevowServer as NS  # pylint: disable=ungrouped-imports
            NS.WorkingDir = WorkingDir
        except Exception:
            LogMessageAndException(_("Nevow/Athena import failed :"))
            webport = None

    try:
        import runtime.WampClient as WC  # pylint: disable=ungrouped-imports
        WC.WorkingDir = WorkingDir
        havewamp = True
    except Exception:
        LogMessageAndException(_("WAMP import failed :"))

# Load extensions
for extention_file, extension_folder in extensions:
    sys.path.append(extension_folder)
    exec(compile(open(os.path.join(extension_folder, extention_file), "rb").read(), os.path.join(extension_folder, extention_file), 'exec'), locals())

# Service name is used as an ID for stunnel's PSK
# Some extension may set 'servicename' to a computed ID or Serial Number
# instead of using commandline '-n'
if servicename is not None and PSKpath is not None:
    ensurePSK(servicename, PSKpath)

runtime.CreatePLCObjectSingleton(
    WorkingDir, argv, statuschange, evaluator, pyruntimevars)

pyroserver = PyroServer(servicename, interface, port)

if havewx:
    taskbar_instance = BeremizTaskBarIcon(pyroserver)

if havetwisted:
    if webport is not None:
        try:
            website = NS.RegisterWebsite(interface, webport)
            pyruntimevars["website"] = website
        except Exception:
            LogMessageAndException(_("Nevow Web service failed. "))

    if havewamp:
        try:
            WC.RegisterWampClient(wampconf, PSKpath)
            WC.RegisterWebSettings(NS)
        except Exception:
            LogMessageAndException(_("WAMP client startup failed. "))

pyro_thread = None

def FirstWorkerJob():
    """
    RPC through pyro/wamp/UI may lead to delegation to Worker,
    then this function ensures that Worker is already
    created when pyro starts
    """
    global pyro_thread, pyroserver

    pyro_thread_started = Lock()
    pyro_thread_started.acquire()
    pyro_thread = Thread(target=pyroserver.PyroLoop,
                         kwargs=dict(when_ready=pyro_thread_started.release),
                         name="PyroThread")

    pyro_thread.start()

    # Wait for pyro thread to be effective
    pyro_thread_started.acquire()

    pyroserver.PrintServerInfo()

    # Beremiz IDE detects LOCAL:// runtime is ready by looking
    # for self.workdir in the daemon's stdout.
    sys.stdout.write(_("Current working directory :") + WorkingDir + "\n")
    sys.stdout.flush()

    runtime.GetPLCObjectSingleton().AutoLoad(autostart)

if havetwisted and havewx:

    waker_func = wx.CallAfter

    # This orders ui loop to signal when ready on Stdout
    waker_func(print,"UI thread started successfully.")

    # interleaved worker copes with wxreactor by delegating all asynchronous
    # calls to wx's mainloop
    runtime.MainWorker.interleave(waker_func, reactor.stop, FirstWorkerJob)

    try:
        reactor.run(installSignalHandlers=False)
    except KeyboardInterrupt:
        pass

    runtime.MainWorker.stop()

elif havewx:

    try:
        app.MainLoop
    except KeyboardInterrupt:
        pass

elif havetwisted:

    ui_thread_started = Lock()
    ui_thread_started.acquire()

    reactor.callLater(0, ui_thread_started.release)

    ui_thread = Thread(
        target=partial(reactor.run, installSignalHandlers=False),
        name="UIThread")
    ui_thread.start()

    ui_thread_started.acquire()
    print("UI thread started successfully.")
    try:
        # blocking worker loop
        runtime.MainWorker.runloop(FirstWorkerJob)
    except KeyboardInterrupt:
        pass
else:
    try:
        # blocking worker loop
        runtime.MainWorker.runloop(FirstWorkerJob)
    except KeyboardInterrupt:
        pass


pyroserver.Quit()
pyro_thread.join()

plcobj = runtime.GetPLCObjectSingleton()
try:
    plcobj.StopPLC()
    plcobj.UnLoadPLC()
except:
    print(traceback.format_exc())

if havetwisted:
    reactor.stop()
    if not havewx:
        ui_thread.join()
elif havewx:
    app.ExitMainLoop()

sys.exit(0)