import os
import subprocess
import sys
from datetime import datetime
from enum import Enum
from urllib.request import urlopen

from app.commons import run_task, log, _DATE_FORMAT
from app.settings import PlayStreamsMode


class Player:
    __VLC_INSTANCE = None
    __PLAY_STREAMS_MODE = PlayStreamsMode.BUILT_IN

    def __init__(self, rewind_callback, position_callback, error_callback, playing_callback):
        try:
            from app.tools import vlc
            from app.tools.vlc import EventType
        except OSError as e:
            log("{}: Load library error: {}".format(__class__.__name__, e))
            raise ImportError
        else:
            self._is_playing = False
            args = "--quiet {}".format("" if sys.platform == "darwin" else "--no-xlib")
            self._player = vlc.Instance(args).media_player_new()
            ev_mgr = self._player.event_manager()

            if rewind_callback:
                # TODO look other EventType options
                ev_mgr.event_attach(EventType.MediaPlayerBuffering,
                                    lambda et, p: rewind_callback(p.get_media().get_duration()),
                                    self._player)
            if position_callback:
                ev_mgr.event_attach(EventType.MediaPlayerTimeChanged,
                                    lambda et, p: position_callback(p.get_time()),
                                    self._player)

            if error_callback:
                ev_mgr.event_attach(EventType.MediaPlayerEncounteredError,
                                    lambda et, p: error_callback(),
                                    self._player)
            if playing_callback:
                ev_mgr.event_attach(EventType.MediaPlayerPlaying,
                                    lambda et, p: playing_callback(),
                                    self._player)

    @classmethod
    def get_instance(cls, rewind_callback=None, position_callback=None, error_callback=None, playing_callback=None):
        if not cls.__VLC_INSTANCE:
            cls.__VLC_INSTANCE = Player(rewind_callback, position_callback, error_callback, playing_callback)
        return cls.__VLC_INSTANCE

    @staticmethod
    def get_play_mode():
        return Player.__PLAY_STREAMS_MODE

    @run_task
    def play(self, mrl=None):
        if mrl:
            self._player.set_mrl(mrl)
        self._player.play()
        self._is_playing = True

    @run_task
    def stop(self):
        if self._is_playing:
            self._player.stop()
            self._is_playing = False

    def pause(self):
        self._player.pause()

    def set_time(self, time):
        self._player.set_time(time)

    @run_task
    def release(self):
        if self._player:
            self._is_playing = False
            self._player.stop()
            self._player.release()

    def set_xwindow(self, xid):
        self._player.set_xwindow(xid)

    def set_nso(self, widget):
        """ Used on MacOS to set NSObject.

            Based on gtkvlc.py[get_window_pointer] example from here:
            https://github.com/oaubert/python-vlc/tree/master/examples
        """
        try:
            import ctypes
            g_dll = ctypes.CDLL("libgdk-3.0.dylib")
        except OSError as e:
            log("{}: Load library error: {}".format(__class__.__name__, e))
        else:
            get_nsview = g_dll.gdk_quartz_window_get_nsview
            get_nsview.restype, get_nsview.argtypes = ctypes.c_void_p, [ctypes.c_void_p]
            ctypes.pythonapi.PyCapsule_GetPointer.restype = ctypes.c_void_p
            ctypes.pythonapi.PyCapsule_GetPointer.argtypes = [ctypes.py_object]
            # Get the C void* pointer to the window
            pointer = ctypes.pythonapi.PyCapsule_GetPointer(widget.get_window().__gpointer__, None)
            self._player.set_nsobject(get_nsview(pointer))

    def set_mrl(self, mrl):
        self._player.set_mrl(mrl)

    def is_playing(self):
        return self._is_playing

    def set_full_screen(self, full):
        self._player.set_fullscreen(full)


class HttpPlayer:
    """ Simple wrapper for VLC media player to interact over http. """

    __VLC_INSTANCE = None
    __PLAY_STREAMS_MODE = PlayStreamsMode.VLC

    class Commands(Enum):
        STATUS = "http://127.0.0.1:{}/requests/status.xml"
        PLAY = "http://127.0.0.1:{}/requests/status.xml?command=in_play&input={}"
        STOP = "http://127.0.0.1:{}/requests/status.xml?command=pl_stop"
        CLEAR = "http://127.0.0.1:{}/requests/status.xml?command=pl_empty"

    def __init__(self, exe, port, is_darwin):
        from concurrent.futures import ThreadPoolExecutor as PoolExecutor

        self._executor = PoolExecutor(max_workers=1)
        self._cmd = [exe, "--no-stats", "--verbose=-1", "--extraintf", "http", "--http-port", port, "--quiet"]
        if not is_darwin:
            self._cmd.append("--one-instance")

        self._p = None
        self._state = None
        self._port = port

    @classmethod
    def get_instance(cls, settings):
        if not cls.__VLC_INSTANCE:
            import shutil

            is_darwin = settings.is_darwin
            # TODO Add options[vlc_exe and port] to the settings!
            exe = "/Applications/VLC.app/Contents/MacOS/VLC" if is_darwin else "/usr/bin/vlc"
            if shutil.which(exe) is None:
                raise ImportError
            cls.__VLC_INSTANCE = HttpPlayer(exe=exe, port=str(9090), is_darwin=is_darwin)
        return cls.__VLC_INSTANCE

    @staticmethod
    def get_play_mode():
        return HttpPlayer.__PLAY_STREAMS_MODE

    @run_task
    def play(self, mrl=None):
        if not self._p or self._p and self._p.poll() is not None:
            self._p = subprocess.Popen(self._cmd + [mrl], preexec_fn=os.setsid)
            self._p.communicate()
        else:
            self._executor.submit(self.open_command, self.Commands.CLEAR)
            self._executor.submit(self.open_command, self.Commands.PLAY, mrl)

    def open_command(self, command, url=None):
        if command is self.Commands.PLAY:
            url = self.Commands.PLAY.value.format(self._port, url)
        else:
            url = command.value.format(self._port)

        try:
            with urlopen(url, timeout=5) as f:
                self._state = command
        except Exception as e:
            log("{}[open_command, {}] error: {}".format(__class__.__name__, command, e))

    def stop(self):
        if self._state is self.Commands.PLAY:
            self._executor.submit(self.open_command, self.Commands.STOP)

    def pause(self):
        pass

    def set_time(self, time):
        pass

    @run_task
    def release(self):
        if self._p and self._p.poll() is None:
            import signal
            # Good explanation here: https://stackoverflow.com/a/4791612
            os.killpg(os.getpgid(self._p.pid), signal.SIGTERM)

    def is_playing(self):
        return self._state is self.Commands.PLAY

    def set_full_screen(self, full):
        pass


class Recorder:
    __VLC_REC_INSTANCE = None

    _CMD = "sout=#std{{access=file,mux=ts,dst={}.ts}}"
    _TR_CMD = "sout=#transcode{{{}}}:file{{mux=mp4,dst={}.mp4}}"

    def __init__(self, settings):
        try:
            from app.tools import vlc
            from app.tools.vlc import EventType
        except OSError as e:
            log("{}: Load library error: {}".format(__class__.__name__, e))
            raise ImportError
        else:
            self._settings = settings
            self._is_record = False
            args = "--quiet {}".format("" if sys.platform == "darwin" else "--no-xlib")
            self._recorder = vlc.Instance(args).media_player_new()

    @classmethod
    def get_instance(cls, settings):
        if not cls.__VLC_REC_INSTANCE:
            cls.__VLC_REC_INSTANCE = Recorder(settings)
        return cls.__VLC_REC_INSTANCE

    @run_task
    def record(self, url, name):
        if self._recorder:
            self._recorder.stop()

        path = self._settings.records_path
        os.makedirs(os.path.dirname(path), exist_ok=True)
        d_now = datetime.now().strftime(_DATE_FORMAT)
        path = "{}{}_{}".format(path, name.replace(" ", "_"), d_now.replace(" ", "_"))
        cmd = self.get_transcoding_cmd(path) if self._settings.activate_transcoding else self._CMD.format(path)
        media = self._recorder.get_instance().media_new(url, cmd)
        media.get_mrl()

        self._recorder.set_media(media)
        self._is_record = True
        self._recorder.play()
        log("Record started {}".format(d_now))

    @run_task
    def stop(self):
        self._recorder.stop()
        self._is_record = False
        log("Recording stopped.")

    def is_record(self):
        return self._is_record

    @run_task
    def release(self):
        if self._recorder:
            self._recorder.stop()
            self._recorder.release()
            self._is_record = False
            log("Recording stopped. Releasing...")

    def get_transcoding_cmd(self, path):
        presets = self._settings.transcoding_presets
        prs = presets.get(self._settings.active_preset)
        return self._TR_CMD.format(",".join("{}={}".format(k, v) for k, v in prs.items()), path)


if __name__ == "__main__":
    pass