#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
#  SDS011_Feinstaub_Sensor.py
#  
#  Copyright 2017 by luetzel <webmaster_at_raspberryblog.de>
#  
#  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 2 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, write to the Free Software
#  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
#  MA 02110-1301, USA.
#  
#  


from __future__ import print_function
import serial, struct, sys, time
import socket,json,requests


ser = serial.Serial()
#ser.port = sys.argv[1]
ser.port = "/dev/serial/by-id/usb-1a86_USB2.0-Serial-if00-port0"
#ser.port = "/dev/ttyUSB5"
ser.baudrate = 9600
sensebox_id="5cf8a49707460b001b43a245"
sensebox_25="5cf8a49707460b001b43a247"
sensebox_10="5cfc0d44a1ba9f001a6e57ae"
url="https://ingress.opensensemap.org/boxes/%s/%s"
pm=[0,0]
pm_count=0
ser.open()
ser.flushInput()


def dump_data(d):
    print(' '.join(x.encode('hex') for x in d))


def process_frame(d):
    #dump_data(d) #debug
    r = struct.unpack('<HHxxBBB', d[2:])
    pm25 = r[0]/10.0
    pm10 = r[1]/10.0
    print(pm25)
    checksum = sum(ord(v) for v in d[2:8])%256
    out=(0,0)
    if (checksum==r[2] and r[3]==0xab):
        out=(pm25,pm10)
    return out

def export_data(pm25,pm10):
    print("PM 2.5: {} μg/m^3  PM 10: {} μg/m^3".format(pm25, pm10))
    r = requests.post(url % (sensebox_id,sensebox_25),json={'value': pm25})
    if r.status_code != requests.codes.ok:
        print("Error %d: %s" % (r.status_code,r.text))
    r = requests.post(url % (sensebox_id,sensebox_10),json={'value': pm10})
    if r.status_code != requests.codes.ok:
        print("Error %d: %s" % (r.status_code,r.text))
    json_out={"time":  int(time.time()*1000),"device": "ragps","payload":{"pm25": int(pm25*1000),"pm10": int(pm10*1000)}}
    try:
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    except:
        print("{}: could not connect to database".format(time.time()))
    else:
        s.connect(("banana", 24048))
        s.sendall(json.dumps(json_out))
        s.close()


def sensor_read():
    byte = 0
    while byte != "\xaa":
        byte = ser.read(size=1)
    d = ser.read(size=10)
    out=(0,0)
    if d[0] == "\xc0":
        out=process_frame(byte + d)
    return out


# 0xAA, 0xB4, 0x06, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0x06, 0xAB
def sensor_wake():
    bytes = ['\xaa', #head
            '\xb4', #command 1
            '\x06', #data byte 1
            '\x01', #data byte 2 (set mode)
            '\x01', #data byte 3 (sleep)
            '\x00', #data byte 4
            '\x00', #data byte 5
            '\x00', #data byte 6
            '\x00', #data byte 7
            '\x00', #data byte 8
            '\x00', #data byte 9
            '\x00', #data byte 10
            '\x00', #data byte 11
            '\x00', #data byte 12
            '\x00', #data byte 13
            '\xff', #data byte 14 (device id byte 1)
            '\xff', #data byte 15 (device id byte 2)
            '\x05', #checksum
            '\xab'] #tail
    for b in bytes:
        ser.write(b)


# xAA, 0xB4, 0x06, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0x05, 0xAB
def sensor_sleep():
    bytes = ['\xaa', #head
            '\xb4', #command 1
            '\x06', #data byte 1
            '\x01', #data byte 2 (set mode)
            '\x00', #data byte 3 (sleep)
            '\x00', #data byte 4
            '\x00', #data byte 5
            '\x00', #data byte 6
            '\x00', #data byte 7
            '\x00', #data byte 8
            '\x00', #data byte 9
            '\x00', #data byte 10
            '\x00', #data byte 11
            '\x00', #data byte 12
            '\x00', #data byte 13
            '\xff', #data byte 14 (device id byte 1)
            '\xff', #data byte 15 (device id byte 2)
            '\x05', #checksum
            '\xab'] #tail
    for b in bytes:
        ser.write(b)


def main(args):
    a = 2
    while a > 1:
        sensor_wake()
        time.sleep(30)
        ser.flushInput()
        pm25=0
        pm10=0
        pm_count=0
        for n in range(5):
            pm_data=sensor_read()
            if(pm_data[0]>0):
                pm25=pm25+pm_data[0]
                pm10=pm10+pm_data[1]
                pm_count=pm_count+1
            time.sleep(2)
        export_data(round(pm25/pm_count,1),round(pm10/pm_count,1))
#        sensor_sleep()
        time.sleep(600)


if __name__ == '__main__':
    import sys
    sys.exit(main(sys.argv))