#!/usr/bin/env python3

# Author: raspbeguy <raspbeguy@hashtagueule.fr>
# 2017-03-12
# License: MIT

import queue
import threading
import signal
import sys
import os
import audioop
import dot3k.lcd as lcd
import dot3k.backlight as backlight
import dot3k.joystick as nav
from mpd import MPDClient

rotate_pause = 10 # delay in rotation steps

char_play = [
    0b10000,
    0b11000,
    0b11100,
    0b11110,
    0b11110,
    0b11100,
    0b11000,
    0b10000,
]

char_pause = [
    0b00000,
    0b11011,
    0b11011,
    0b11011,
    0b11011,
    0b11011,
    0b11011,
    0b00000,
]

char_stop = [
    0b00000,
    0b11111,
    0b11111,
    0b11111,
    0b11111,
    0b11111,
    0b11111,
    0b00000,
]


q = queue.Queue()

def vumeter():
    fifo = os.open('/tmp/mpd.fifo', os.O_RDONLY)
    while run_event.is_set():
        try:
            rawStream = os.read(fifo, 4096)
        except OSError as err:
            if err.errno == errno.EAGAIN or err.errno == errno.EWOULDBLOCK:
                rawStream = None
            else:
                raise
        if rawStream:
            backlight.set_graph(audioop.rms(rawStream,2)/32768)
    backlight.set_graph(0)


def stringrotate(text, width, step):
    if len(text) > width:
        fulltext = text + " - "
        fulltext = fulltext[step:] + fulltext[:step]
        return fulltext[:width]
    else:
        return text

def display():
    title = ''
    artist = ''
    album = ''
    song_file = '' # Useful to determine if current song actually changed
    step_title = step_artist = step_album = 0
    while run_event.is_set():
        try:
            arg = q.get(timeout=0.2)
            status = arg['status']['state']

            if status == "play":
                backlight.rgb(0, 0, 255) # green
                lcd.create_char(0, char_play)
            elif status == "pause":
                backlight.rgb(0, 255, 0) # blue
                lcd.create_char(0, char_pause)
            else:
                backlight.rgb(255, 0, 0)
                lcd.create_char(0, char_stop)

            if status not in {'play','pause'} or song_file != arg['song']['file']:
                song_file   = arg['song']['file'] if 'file' in  arg['song'].keys() else ''
                title       = arg['song']['title'] if 'title' in  arg['song'].keys() else ''
                artist      = arg['song']['artist'] if 'artist' in  arg['song'].keys() else ''
                album       = arg['song']['album'] if 'album' in  arg['song'].keys() else ''
                lcd.clear()
                lcd.set_cursor_position(0, 0)
                lcd.write(chr(0))

                step_title = step_artist = step_album = 0
                delay_title = delay_artist = delay_album = rotate_pause

                if len(title) <= 15:
                    lcd.set_cursor_position(1, 0)
                    lcd.write(title)
                if len(artist) <= 16:
                    lcd.set_cursor_position(0, 1)
                    lcd.write(artist)
                if len(album) <= 16:
                    lcd.set_cursor_position(0, 2)
                    lcd.write(album)

        except queue.Empty:
            if len(title) > 15:
                if step_title == 0 and delay_title > 0:
                    delay_title -= 1
                else:
                    step_title = (step_title + 1) % (len(title) + 3)
                    if delay_title == 0:
                        delay_title = rotate_pause
            if len(artist) > 16:
                if step_artist == 0 and delay_artist > 0:
                    delay_artist -= 1
                else:
                    step_artist = (step_artist + 1) % (len(artist) + 3)
                    if delay_artist == 0:
                        delay_artist = rotate_pause
            if len(album) > 16:
                if step_album == 0 and delay_album > 0:
                    delay_album -= 1
                else:
                    step_album  = (step_album + 1) % (len(album) + 3)
                    if delay_album == 0:
                        delay_album = rotate_pause

        if len(title) > 15:
            lcd.set_cursor_position(1, 0)
            lcd.write(stringrotate(title, 15, step_title))
        if len(artist) > 16:
            lcd.set_cursor_position(0, 1)
            lcd.write(stringrotate(artist, 16, step_artist))
        if len(album) > 16:
            lcd.set_cursor_position(0, 2)
            lcd.write(stringrotate(album, 16, step_album))
    lcd.clear()

@nav.on(nav.BUTTON)
def button_center(pin):
    client = MPDClient() # Please close your eyes
    client.connect("localhost", 6600) # Dirty dirty dirty...
    if client.status()['state'] in {'play','pause'}:
        client.pause()
    else:
        client.play()
    client.close() # Okay, you can open your eyes

@nav.on(nav.LEFT)
def button_left(pin):
    client = MPDClient() # Please close your eyes
    client.connect("localhost", 6600) # Dirty dirty dirty...
    client.previous()
    client.close() # Okay, you can open your eyes

@nav.on(nav.RIGHT)
def button_right(pin):
    client = MPDClient() # Please close your eyes
    client.connect("localhost", 6600) # Dirty dirty dirty...
    client.next()
    client.close() # Okay, you can open your eyes

def on_exit(sig, func=None):
    run_event.clear()
    t_display.join()
    t_vumeter.join()
    backlight.rgb(0, 0, 0)
    backlight.rgb(0, 0, 0)
    print("Screen sound be blank and light off now.")
    sys.exit(0)

lcd.set_contrast(50)
run_event = threading.Event()
run_event.set()
client = MPDClient()
client.connect("localhost", 6600)

t_display = threading.Thread(name='display',target=display)
t_vumeter = threading.Thread(name='vumeter',target=vumeter)
t_display.start()
t_vumeter.start()

signal.signal(signal.SIGTERM, on_exit)
try:
    while True:
        q.put({'song': client.currentsong(), 'status' : client.status()})
        client.idle('player')
except KeyboardInterrupt:
    on_exit(None)