#!/usr/bin/env python3
# -*- coding: utf-8 -*-

# Copyright (c) 2009,2010,2012,2019 kaliko <kaliko@azylum.org>
#
#   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 3 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, see <http://www.gnu.org/licenses/>.
#

"""
DOC:
    heavily borrowed from perl script mpdtoys and converted to python.
    mpdtoys © 2007 Joey Hess <joey@kitenet.net>
    http://kitenet.net/~joey/code/mpdtoys
"""

import argparse
import sys

from time import sleep
from os.path import basename

import musicpd


VERSION = '0.2'
DESC = """Fade in/out to <final volume level> over <time>.
Defaults are from 0% to 50% when paused or stopped 
and from current volume to 10th of it if playing,
both over 10 minutes."""
DESC = """Fade in/out to <final volume level> over <time>.
Defaults are from 0% to 50% when paused or stopped and from current volume to 10th of it if playing, both over 10 minutes."""
EPILOG = """You might need to set your audio_output with "always_on yes" for
this command to work properly.

Set MPD host/port in env. var"""

class Sleep(musicpd.MPDClient):
    """"""
    script_info = dict({
        'prog': basename(__file__),
        'description': DESC,
        'epilog': EPILOG,
        'formatter_class': argparse.RawDescriptionHelpFormatter,
    })

    def __init__(self):
        """"""
        musicpd.MPDClient.__init__(self)
        self.tempo = 600
        self.volum = None
        self._get_args()
        self._run()

    def _test_volume_access(self):
        status = self.status()
        if 'volume' not in status:
            print('Mixer not available!')
            print('Try to set the always_on audio_output option on.')
            sys.exit(1)

    def _get_args(self):
        """"""
        parser = argparse.ArgumentParser(**self.__class__.script_info)
        parser.add_argument('--version', action='version',
                            version='v%s' % VERSION)
        group = parser.add_mutually_exclusive_group()
        group.add_argument('-m', '--minutes', type=int,
                           help='duration to fade in/out over')
        group.add_argument('-s', '--seconds', type=int,
                           help='duration to fade in/out over')
        parser.add_argument('volume', type=int, nargs='?',
                            help='final volume level')
        args = parser.parse_args()
        if args.minutes:
            self.tempo = args.minutes*60
        if args.seconds:
            self.tempo = args.seconds
        if args.volume:
            self.volum = args.volume

    def _run(self):
        """"""
        self.connect()
        self.mpd_state = str(self.status().get('state'))
        if self.mpd_state == 'play':
            self.mpd_vol = int(self.status().get('volume'))
            if not self.volum:
                self.volum = self.mpd_vol // 10
            if self.volum > self.mpd_vol:
                print('Error: specified min volume (%d%%) > to current volume (%d%%)' % (
                    self.volum, self.mpd_vol))
                sys.exit(1)
            print('fading down from %d%% to %d%% over %ss' % (self.mpd_vol, self.volum, self.tempo), file=sys.stdout)
            if self.fade(self.mpd_vol, self.volum):
                self.stop()
        elif self.mpd_state in ['stop', 'pause']:
            self._test_volume_access()
            if not self.volum:
                self.volum = int(50)
            print('fading up from 0%% to %d%% over %ss' % (self.volum, self.tempo), file=sys.stdout)
            self.mpd_vol = 0
            self.setvol(0)
            self.play()
            self.fade(self.mpd_vol, self.volum)

    def fade(self, mpd_vol, target):
        """"""
        # TODO: handle possible lost connections
        span = target - mpd_vol
        step = span / (10*self.tempo)
        vol = mpd_vol
        if step == 0:
            return True
        while True:
            if int(vol) != int(self.status().get('volume')):
                sys.stderr.write(
                    'Warning: external volume change, aborting!\n')
                return False
            vol += step
            self.setvol(int(vol))
            if abs(vol - target) < 1.1*abs(step):
                self.setvol(target)
                return True
            sleep(.1)


# Script starts here
if __name__ == '__main__':
    try:
        Sleep()
    except KeyboardInterrupt:
        sys.stdout.write('exit')

# VIM MODLINE
# vim: ai ts=4 sw=4 sts=4 expandtab