"""
    schedule.telnetliquidsoap
    ~~~~~~~~~

    Module exposing API to directly communicate with Liquidsoap via telnet.

    :author: (c) 2012 by Martin Konecny.
    :license: GPLv3, see LICENSE for more details.
"""
import telnetlib
from threading import Lock
from timeout import ls_timeout

def create_liquidsoap_annotation(media):
    # We need liq_start_next value in the annotate. That is the value that 
    # controls overlap duration of crossfade.
    return ('annotate:media_id="%s",liq_start_next="0",liq_fade_in="%s",' +
            'liq_fade_out="%s",liq_cue_in="%s",liq_cue_out="%s",' +
            'schedule_table_id="%s",replay_gain="%s dB":%s') % \
            (media['id'], 
                    float(media['fade_in']) / 1000, 
                    float(media['fade_out']) / 1000, 
                    float(media['cue_in']), 
                    float(media['cue_out']), 
                    media['row_id'], 
                    media['replay_gain'], 
                    media['dst'])

class TelnetLiquidsoap:

    def __init__(self, logger, ls_host, ls_port, queues):
        self.telnet_lock = Lock()
        self.ls_host = ls_host
        self.ls_port = ls_port
        self.logger = logger
        self.queues = queues
        self.current_prebuffering_stream_id = None

    def __connect(self):
        return telnetlib.Telnet(self.ls_host, self.ls_port)

    def __is_empty(self, queue_id):
        tn = self.__connect()
        msg = '%s.queue\nexit\n' % queue_id
        tn.write(msg)
        output = tn.read_all().splitlines()
        if len(output) == 3:
            return len(output[0]) == 0
        else:
            raise Exception("Unexpected list length returned: %s" % output)

    @ls_timeout
    def queue_clear_all(self):
        with self.telnet_lock:
            tn = self.__connect()

            for i in self.queues:
                msg = 'queues.%s_skip\n' % i
                self.logger.debug(msg)
                tn.write(msg)
            
            tn.write("exit\n")
            self.logger.debug(tn.read_all())

    @ls_timeout
    def queue_remove(self, queue_id):
        with self.telnet_lock:
            tn = self.__connect()

            msg = 'queues.%s_skip\n' % queue_id
            self.logger.debug(msg)
            tn.write(msg)
            
            tn.write("exit\n")
            self.logger.debug(tn.read_all())

    @ls_timeout
    def queue_push(self, queue_id, media_item):
        with self.telnet_lock:
            if not self.__is_empty(queue_id):
                raise QueueNotEmptyException()

            tn = self.__connect()
            annotation = create_liquidsoap_annotation(media_item)
            msg = '%s.push %s\n' % (queue_id, annotation.encode('utf-8'))
            self.logger.debug(msg)
            tn.write(msg)

            show_name = media_item['show_name']
            msg = 'vars.show_name %s\n' % show_name.encode('utf-8')
            tn.write(msg)
            self.logger.debug(msg)

            tn.write("exit\n")
            self.logger.debug(tn.read_all())

    @ls_timeout
    def stop_web_stream_buffer(self):
        with self.telnet_lock:
            tn = self.__connect()

            msg = 'http.stop\n'
            self.logger.debug(msg)
            tn.write(msg)

            msg = 'dynamic_source.id -1\n'
            self.logger.debug(msg)
            tn.write(msg)

            tn.write("exit\n")
            self.logger.debug(tn.read_all())

    @ls_timeout
    def stop_web_stream_output(self):
        with self.telnet_lock:
            tn = self.__connect()

            msg = 'dynamic_source.output_stop\n'
            self.logger.debug(msg)
            tn.write(msg)

            tn.write("exit\n")
            self.logger.debug(tn.read_all())


    @ls_timeout
    def start_web_stream(self, media_item):
        with self.telnet_lock:
            tn = self.__connect()

            #TODO: DO we need this?
            msg = 'streams.scheduled_play_start\n'
            tn.write(msg)

            msg = 'dynamic_source.output_start\n'
            self.logger.debug(msg)
            tn.write(msg)

            tn.write("exit\n")
            self.logger.debug(tn.read_all())

            self.current_prebuffering_stream_id = None
        
    @ls_timeout
    def start_web_stream_buffer(self, media_item):
        with self.telnet_lock:
            tn = self.__connect()

            msg = 'dynamic_source.id %s\n' % media_item['row_id']
            self.logger.debug(msg)
            tn.write(msg)

            msg = 'http.restart %s\n' % media_item['uri'].encode('latin-1')
            self.logger.debug(msg)
            tn.write(msg)

            tn.write("exit\n")
            self.logger.debug(tn.read_all())

            self.current_prebuffering_stream_id = media_item['row_id']

    @ls_timeout
    def get_current_stream_id(self):
        with self.telnet_lock:
            tn = self.__connect()

            msg = 'dynamic_source.get_id\n'
            self.logger.debug(msg)
            tn.write(msg)

            tn.write("exit\n")
            stream_id = tn.read_all().splitlines()[0]
            self.logger.debug("stream_id: %s" % stream_id)

            return stream_id

    @ls_timeout
    def disconnect_source(self, sourcename):
        self.logger.debug('Disconnecting source: %s', sourcename)
        command = ""
        if(sourcename == "master_dj"):
            command += "master_harbor.kick\n"
        elif(sourcename == "live_dj"):
            command += "live_dj_harbor.kick\n"

        with self.telnet_lock:
            tn = self.__connect()
            self.logger.info(command)
            tn.write(command)
            tn.write('exit\n')
            tn.read_all()

    @ls_timeout
    def telnet_send(self, commands):
        with self.telnet_lock:
            tn = self.__connect()
            for i in commands:
                self.logger.info(i)
                tn.write(i)

            tn.write('exit\n')
            tn.read_all()

    @ls_timeout
    def switch_source(self, sourcename, status):
        self.logger.debug('Switching source: %s to "%s" status', sourcename, 
                status)
        command = "streams."
        if sourcename == "master_dj":
            command += "master_dj_"
        elif sourcename == "live_dj":
            command += "live_dj_"
        elif sourcename == "scheduled_play":
            command += "scheduled_play_"

        if status == "on":
            command += "start\n"
        else:
            command += "stop\n"

        self.telnet_send([command])

    @ls_timeout
    def liquidsoap_get_info(self):
        self.logger.debug("Checking to see if Liquidsoap is running")
        response = ""
        with self.telnet_lock:
            tn = self.__connect()
            msg = "version\n"
            tn.write(msg)
            tn.write("exit\n")
            response = tn.read_all()

        return response

    @ls_timeout
    def update_liquidsoap_station_name(self, station_name):
        with self.telnet_lock:
            tn = self.__connect()
            command = ('vars.station_name %s\n' % 
                    station_name).encode('utf-8')
            self.logger.info(command)
            tn.write(command)
            tn.write('exit\n')
            tn.read_all()

    @ls_timeout
    def get_liquidsoap_connection_status(self, current_time):
        output = None
        with self.telnet_lock:
            tn = self.__connect()
            # update the boot up time of Liquidsoap. Since Liquidsoap is not 
            # restarting, we are manually adjusting the bootup time variable 
            # so the status msg will get updated.
            boot_up_time_command = "vars.bootup_time %s\n" % str(current_time)
            self.logger.info(boot_up_time_command)
            tn.write(boot_up_time_command)

            connection_status = "streams.connection_status\n"
            self.logger.info(connection_status)
            tn.write(connection_status)

            tn.write('exit\n')
            output = tn.read_all()

        return output

    @ls_timeout
    def update_liquidsoap_stream_format(self, stream_format):
        with self.telnet_lock:
            tn = self.__connect()
            command = ('vars.stream_metadata_type %s\n' % 
                    stream_format).encode('utf-8')
            self.logger.info(command)
            tn.write(command)
            tn.write('exit\n')
            tn.read_all()

    @ls_timeout
    def update_liquidsoap_transition_fade(self, fade):
        with self.telnet_lock:
            tn = self.__connect()
            command = ('vars.default_dj_fade %s\n' % fade).encode('utf-8')
            self.logger.info(command)
            tn.write(command)
            tn.write('exit\n')
            tn.read_all()

class DummyTelnetLiquidsoap:

    def __init__(self, telnet_lock, logger):
        self.telnet_lock = telnet_lock
        self.liquidsoap_mock_queues = {}
        self.logger = logger

        for i in range(4):
            self.liquidsoap_mock_queues["s"+str(i)] = []

    @ls_timeout
    def queue_push(self, queue_id, media_item):
        try:
            self.telnet_lock.acquire()

            self.logger.info("Pushing %s to queue %s" % (media_item, queue_id))
            from datetime import datetime
            print "Time now: %s" % datetime.utcnow()

            annotation = create_liquidsoap_annotation(media_item)
            self.liquidsoap_mock_queues[queue_id].append(annotation)
        except Exception:
            raise
        finally:
            self.telnet_lock.release()

    @ls_timeout
    def queue_remove(self, queue_id):
        try:
            self.telnet_lock.acquire()

            self.logger.info("Purging queue %s" % queue_id)
            from datetime import datetime
            print "Time now: %s" % datetime.utcnow()

        except Exception:
            raise
        finally:
            self.telnet_lock.release()

class QueueNotEmptyException(Exception):
    pass