#!/usr/bin/env python
#NOTE:
# This sensor is on port 0x04, so not compatible with grovepi unless you load an alternate firmware
# This is work in progress, would need logic analyzer and arduino to get working
# Error:
#   Traceback (most recent call last):
#  File "multichannel_gas_sensor.py", line 67, in <module>
#    m= MutichannelGasSensor()
#  File "multichannel_gas_sensor.py", line 21, in __init__
#    if self.readR0() >= 0:
#  File "multichannel_gas_sensor.py", line 27, in readR0
#    rtnData = self.readData(0x11)
#  File "multichannel_gas_sensor.py", line 52, in readData
#    buffer=bus.read_i2c_block_data(self.address, cmd, 4)
#IOError: [Errno 5] Input/output error
#
# LINKS
# http://www.seeedstudio.com/wiki/Grove_-_Multichannel_Gas_Sensor
# https://github.com/Seeed-Studio/Mutichannel_Gas_Sensor
import time,sys
from Adafruit_I2C import Adafruit_I2C

import smbus

# use the bus that matches your raspi version
#rev = GPIO.RPI_REVISION
# if True:
#     bus = smbus.SMBus(1)
# else:
#     bus = smbus.SMBus(0)

class MutichannelGasSensor:
    address = None
    is_connected = 0
    res=[0]*3

    def __init__(self, mode=1, address=0x04, i2c=None, **kwargs):
        i2c = Adafruit_I2C(0x04, busnum=2, debug=True)
        bus = smbus.SMBus(2)

        self._device = i2c
        self.address=0x04
        self.adcValueR0_NH3_Buf = 0;
        self.adcValueR0_CO_Buf = 0;
        self.adcValueR0_NO2_Buf = 0;


        print "Led on"
        #dta_test = [11, 1]
        #self._device.writeList(address, dta_test);
        bus.write_word_data(address, 11, 1)
        bus.write_word_data(address, 10, 1)

    #return

        #BEGIN
        version = self.get_addr_dta(6, 0)
        print version

        #POWER ON
        dta_test = [11,1]
        self._device.writeList(self.address, dta_test)
        time.sleep(1)
        #self.calcGas()


    def calcGas(self):
        # how to calc ratio/123

        #ledON
        dta_test = [10, 1]
        self._device.writeList(self.address, dta_test)
        time.sleep(1)

        print "CalcGas"
        #A0_0 = self.get_addr_dta(6, 8);
        time.sleep(1)
        #A0_1 = self.get_addr_dta(6, 10);
        time.sleep(1)
        A0_2 = self.get_addr_dta(6, 12);

        #print "A0_0: " + str(A0_0);
        #print "A0_1: " + str(A0_1);
        print "A0_2: " + str(A0_2);

        # An_0 = get_addr_dta(CH_VALUE_NH3);
        # An_1 = get_addr_dta(CH_VALUE_CO);
        # An_2 = get_addr_dta(CH_VALUE_NO2);

        # ratio0 = (float)An_0/(float)A0_0*(1023.0-A0_0)/(1023.0-An_0);
        # ratio1 = (float)An_1/(float)A0_1*(1023.0-A0_1)/(1023.0-An_1);
        # ratio2 = (float)An_2/(float)A0_2*(1023.0-A0_2)/(1023.0-An_2);


    def get_addr_dta(self, addr_reg, __dta):
        self._device.write8(0x04, addr_reg)
        time.sleep(1)
        self._device.write8(0x04, __dta)
        time.sleep(1)

        testArray = self._device.readList(self.address, 2)

        dta=0
        raw=[None] * 10
        cnt = 0

        if raw[0] == 0:
            print "ERRORE GET ADDR DATA"
            return
        dta = testArray[0]
        dta <<= 8
        dta += testArray[1]

        if addr_reg == 8: #CH_VALUE_NH3
            self.adcValueR0_NH3_Buf = dta;
        elif addr_reg == 10: #CH_VALUE_CO
            self.adcValueR0_CO_Buf = dta;
        elif addr_reg == 12: #CH_VALUE_NO2
            self.adcValueR0_NO2_Buf = dta;

        print dta
        return dta

    def sendI2C(self,cmd):
        bus.write_byte(self.address, cmd)


if __name__ == "__main__":
    m = MutichannelGasSensor()