import sys
import time
from pyqtgraph.Qt import QtCore, QtGui
import numpy as np
import pyqtgraph as pg
import serial



nloop = 1000
nloopfourier = nloop/2+1 # the length of the FFT array
naverage = 75 #75
path1 = 0*np.ones(nloop)
path2 = 0*np.ones(nloopfourier)

hiarr = np.zeros(naverage)
port = "/dev/tty.usbserial-FT9P3WMR"

def lefttoright(x):
    ''' this is just a helper function that transforms
right adjusted binarys to left adjusted ones, with input and output as decimals
'''
    binin= bin(x)[2:]
    binout=(binin.zfill(8))[::-1]
    res = int(binout, 2)
    return res

class App(QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(App, self).__init__(parent)

        #### Create Gui Elements ###########
        self.mainbox = QtGui.QWidget()
        self.setCentralWidget(self.mainbox)
        self.mainbox.setLayout(QtGui.QVBoxLayout())

        self.canvas = pg.GraphicsLayoutWidget()
        self.mainbox.layout().addWidget(self.canvas)

        self.label = QtGui.QLabel()
        self.mainbox.layout().addWidget(self.label)

        #  line plots        
        self.otherplot = self.canvas.addPlot()
        self.h1 = self.otherplot.plot(pen='y')
        
        self.canvas.nextRow()   
        self.otherplot = self.canvas.addPlot()
        self.h2 = self.otherplot.plot(pen='y')


        self.counter = 0
        self.fps = 0.
        self.lastupdate = time.time()

        #### Start  #####################
        self._update()

    def _update(self):
        global zerosig, path1, path2
        #the period of the main loop is 24s as measured manually
        tmax=24.0
        self.xdata1= np.linspace(0, tmax, nloop)
        self.ydata1 = path1
        self.h1.setData(self.xdata1, self.ydata1)

        self.xdata2 = np.array([tmax/float(i+1) for i in range(nloopfourier)])
        self.ydata2 = path2
        self.h2.setData(self.xdata2,self.ydata2)
        
        now = time.time()
        dt = (now-self.lastupdate)
        if dt <= 0:
            dt = 0.000000000001
        fps2 = 1.0 / dt
        self.lastupdate = now
        self.fps = self.fps * 0.9 + fps2 * 0.1
        tx = 'Mean Frame Rate:  {fps:.3f} FPS'.format(fps=self.fps )
        self.label.setText(tx)
        QtCore.QTimer.singleShot(1, self._update)
        self.counter += 1
        for i in range(naverage):
            hiarr[i]=lefttoright(ord(ser.read()))
#             hiarr[i]=ord(ser.read()) 
        reading = np.average(hiarr)
        path1 = np.roll(path1, -1) #this gives a constant shift of a time graph
        # to normalize the signal, the log is used with respect
        #to an average value of hiarr(190 in my case)
        path1[-1] = reading  # this removes the rolling of "0" and "-1" elements and adds new datum
        #20*np.log10(reading/190.0)
        #below is the fourier transform conversion to obtain the average period
        fftarr = np.fft.rfft(path1)
        path2 = np.imag(fftarr)



if __name__ == '__main__':
    ser = serial.Serial(port,115200) # the maximum baud rate for the serial cable
    app = QtGui.QApplication(sys.argv)
    thisapp = App()
    thisapp.show()
    sys.exit(app.exec_())