# Control script for the piPlayer. In order to run with PulseAudio, the OSS
# sound driver has to be set as first option in ~/.moc/config
# The mocp server is then run over the padsp wrapper.
#
# ~/.moc/config
#   # Use OSS for Pulseaudio compatibility (run 'padsp mocp')
#   SoundDriver = OSS:ALSA:JACK

import RPi.GPIO as GPIO
import logging
import time
import subprocess
import select  # see http://stackoverflow.com/a/10759061/3761783
import os

# Configuration
MUSIC_BASE_DIRECTORY = "/media/share/Audio/Kinder/"
SOUND_SCANNING = "/home/pi/scanning.mp3"
SOUND_OK = "/home/pi/263133__pan14__tone-beep.mp3"
SOUND_SCAN_FAIL = "/home/pi/159367__huminaatio__7-error.mp3"
SOUND_PLAYBACK_ERROR = "/home/pi/no.mp3"
QR_SCANNER_TIMEOUT = 3
BUTTON_PAUSE = 0.4

logging.basicConfig(level=logging.DEBUG, format='%(asctime)s.%(msecs)d %(levelname)s - %(message)s')
logging.info('Initializing')

# photo sensor on PIN 4
GPIO.setmode(GPIO.BCM)
GPIO.setup(4, GPIO.IN)

# LED on PIN 17
GPIO.setup(17, GPIO.OUT)
GPIO.output(17, GPIO.LOW)

# Buttons on PINs 14, 15 and 18
GPIO.setup(14, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(15, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(18, GPIO.IN, pull_up_down=GPIO.PUD_UP)

photo_sensor_still_active = False

try:
    logging.info('Start moc server')
    subprocess.call(["padsp", "mocp", "--server"])
    subprocess.call(["mocp", "--clear"])
    subprocess.call(["mocp", "-l", SOUND_OK])
    
    while True:
        
        # TODO what's a good value here?
        time.sleep(0.01)
        
        if (GPIO.input(14) == False):
            logging.debug('mocp --previous')
            subprocess.call(["mocp", "--previous"])
            time.sleep(BUTTON_PAUSE)
            # TODO wait for ~0.25 s, if button is still pressed, seek instead of skipping
    
        if (GPIO.input(15) == False):
            logging.debug('mocp --toggle-pause')
            subprocess.call(["mocp", "--toggle-pause"])
            time.sleep(BUTTON_PAUSE)
    
        if (GPIO.input(18) == False):
            logging.debug('mocp --next')
            subprocess.call(["mocp", "--next"])
            time.sleep(BUTTON_PAUSE)
            # TODO wait for ~0.25 s, if button is still pressed, seek instead of skipping
        
        # check photo sensor
        if ((not photo_sensor_still_active) and (GPIO.input(4) == GPIO.HIGH)):
            logging.debug('Photo sensor active, activating light and camera')
            subprocess.call(["mocp", "-l", SOUND_SCANNING])
            
            # turn LED on
            GPIO.output(17, GPIO.HIGH)
            
            # scan QR code
            zbarcam = subprocess.Popen(['zbarcam', '--nodisplay', '--raw', '-Sdisable', '-Sqrcode.enable', '--prescale=320x240', '/dev/video0'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
            
            poll_obj = select.poll()
            poll_obj.register(zbarcam.stdout, select.POLLIN)
            
            # wait for scan result (or timeout)
            start_time = time.time()
            poll_result = False
            while ((time.time() - start_time) < QR_SCANNER_TIMEOUT and (not poll_result)):
                poll_result = poll_obj.poll(100)
            
            if (poll_result):
                
                try:
                
                    qr_code = zbarcam.stdout.readline().rstrip()
                    qr_code = qr_code.decode("utf-8") # python3
                    logging.debug("QR Code: {}".format(qr_code))
                    
                    if (not qr_code.startswith("http://")):
                        # create full path
                        full_path = MUSIC_BASE_DIRECTORY + qr_code
    
                        logging.debug("Full Path {}".format(full_path))
                        if (not os.path.isfile(full_path)):
                            logging.debug("not a file > add as directory")
                            directory = full_path
                            logging.debug("Directory {}".format(directory))
                        else:
                            logging.debug("it's a file")
                            directory = os.path.dirname(os.path.realpath(full_path))
                            filename = os.path.basename(full_path)
                            logging.debug("Directory {}".format(directory))
                            logging.debug("Filename {}".format(filename))
                        
                        os.chdir(directory)
                        
                        #onlyfiles = [f for f in os.listdir('.') if os.path.isfile(os.path.join('.', f))]
                        #logging.debug(onlyfiles)
                        
                    else:
                        logging.debug("URL > open as stream")
                        stream_url = qr_code
                    
                    subprocess.call(["mocp", "--clear"])
                    subprocess.call(["mocp", "--stop"])
    
                    logging.debug("Stopped")
                    
                    # play confirmation sound
                    subprocess.call(["mocp", "-l", SOUND_OK])
                    
                    if ('stream_url' in locals()):
                        logging.debug("Add stream")
                        subprocess.check_call(["mocp", "-a", stream_url])
                        del stream_url
                    elif ('filename' in locals()):
                        logging.debug("Add file {}".format(filename))
                        subprocess.check_call(["mocp", "-a", filename])
                        del filename
                    else:
                        logging.debug("Add directory {}".format(directory))
                        subprocess.check_call(["mocp", "-a", "."])
                    
                    # subprocess.check_call(["mocp", "-a", target, "-p"])
                    logging.debug("Start playback")
                    subprocess.check_call(["mocp", "-p"])
                    
                except subprocess.CalledProcessError as e:
                    logging.debug("Error starting playback, mocp returned {}".format(e.returncode))
                    logging.debug(e.output)
                    subprocess.call(["mocp", "-l", SOUND_PLAYBACK_ERROR])
                except FileNotFoundError as e:
                    logging.debug("Could not open directory {}".format(directory))
                    subprocess.call(["mocp", "-l", SOUND_PLAYBACK_ERROR])
            else:
                logging.debug('Timeout on zbarcam')
                subprocess.call(["mocp", "-l", SOUND_SCAN_FAIL])
                
            # consider the photo sensor to be blocked
            photo_sensor_still_active = True
            
            zbarcam.terminate()
            
            # LED off
            GPIO.output(17, GPIO.LOW)
            
        elif (GPIO.input(4) == GPIO.LOW):
            # the photo sensor is not blocked (anymore)
            photo_sensor_still_active = False
            
# Exit when Ctrl-C is pressed
except KeyboardInterrupt:
        logging.info('Close moc server')
        subprocess.call(["mocp", "--exit"])
        logging.info('Reset GPIO configuration and close')
GPIO.cleanup()