from flask_socketio import SocketIO
from gpiozero import Button, LED
from time import sleep
import io                               # To check if we are on a Raspberry Pi
import subprocess

class Raspberry(object):
    """
    This class will manage three things :
    - Connecting to a USB webcam
    - Managing a push button
    - Activating a flash ( or light )
    - Flash an indicator light

    """
    def __init__(self, printer, app, socketio, button_gpio_port_number, indicator_gpio_port_number, is_flash_present,):
        self.printer = printer
        self.socketio = socketio
        self.app = app

        self.is_flash_present = is_flash_present
        self.button_gpio = button_gpio_port_number
        self.led_gpio = indicator_gpio_port_number
        self.image_path = self.app.config['UPLOAD_FOLDER'] + '/image.jpg'

    def initialise_gpio(self):

        self.button = Button(self.button_gpio)
        self.led = LED(self.led_gpio)

        button.when_pressed = self.on_button_pressed()


    def is_raspberry_pi(self, raise_on_errors=False):
        # Check if we are running on a raspberry pi
        try:
            with io.open('/proc/cpuinfo', 'r') as cpuinfo:
                found = False
                for line in cpuinfo:
                    if line.startswith('Hardware'):
                        found = True
                        label, value = line.strip().split(':', 1)
                        value = value.strip()
                        if value not in (
                            'BCM2708',
                            'BCM2709',
                            'BCM2711',
                            'BCM2835',
                            'BCM2836'
                        ):
                            self.app.logger.debug('This system does not appear to be a Raspberry Pi.')
                            return False

                if not found:
                    self.app.logger.error('Couldn\'t get sufficient hardware information from /proc/cpuinfo, Unable to determine if we are on a Raspberry Pi.')
                    return False
        except IOError:
            self.app.logger.error('Unable to open `/proc/cpuinfo`.')
            return False

        self.app.logger.debug('It seems we are on a Raspberry Pi')
        return True

    def take_picture(self):
        # return a path to a picture
        try:
            subprocess.run(['fswebcam', '--no-banner', self.image_path])
        except Exception as e:
            self.app.logger.error('Unable to take a picture :' + e)
            raise e
        return True

    def flash(state):
        if state:
            # turn on the flash
            pass
        else:
            # turn off the flash
            pass

    def flash_indicator(self):
        # The indicator will flash three times before return true
        self.led.on()
        sleep(0.1)
        self.led.off()
        sleep(1)
        self.led.on()
        sleep(0.1)
        self.led.off()
        sleep(1)
        self.led.on()
        sleep(0.1)
        self.led.off()

    def on_button_pressed():
        self.socketio.emit('button_pressed')  # Notify clients that a button has been pressed on the raspberry pi
        self.flash_indicator()  # The indicator will flash a countdown LED
        self.flash(True)
        try:
            self.take_picture()
            self.printer.print_image(self.image_path)
        except Exception as e:
            app.logger.error("Could not take a picture after the button press : " + e)
            self.led.on()
        self.flash(False)
        self.socketio.emit('picture_taken')  # Notify clients that a picture has been taken