# encoding: UTF-8

import numpy

class BATE(object):

    def __init__(self):
        self.reset()
    
    def parse(self, l):
        """P parse internal pressure sensor packet
see the MS5534C datasheet for the calibration algorithm
The arrays in the datasheet are indexed based 1.
"""


        if l[0] != 'P':
            return

        sensor = int(l[1])

        ll = [int(i,0) for i in l.split()[1:]]
        for i in ll[1:]:
            if i == 0xba7e:
                raise self.NM64Error("BaTe magic token mismatch %s" % l)
        Word = [0]+ll[0:4] 
        D = ll[3:6]          # Word C, and D are indexed base 1
        C = [0]*7
        C[1] = Word[1] >> 1
        C[2] = ((Word[3] & 0x3f) << 6) | (Word[4] & 0x3f)
        C[3] = Word[4] >> 6
        C[4] = Word[3] >> 6
        C[5] = ((Word[1] & 1) << 10) | (Word[2] >> 6)
        C[6] = Word[2] & 0x3f
        
        UT1 = 8*C[5]+20224
        dT = D[2] - UT1
        TEMP = 200 + dT*(C[6]+50)/1024.
    
        OFF = C[2]*4 + ((C[4]-512)*dT)/4096.
        SENS = C[1] + (C[3]*dT)/1024. + 24576
        X = (SENS * (D[1]-7168))/16384. - OFF
        P = X*10/32. + 2500

        P /= 10.0
        TEMP /= 10.0

        self.BaTe += (1, TEMP, P, TEMP**2, P**2)
        return (sensor, P, TEMP)
    
    def reset(self):
        self.BaTe = numpy.zeros((5,))

    def mean(self):
        n = self.BaTe[0]
        if n:
            TEMP = self.BaTe[1]/n
            P = self.BaTe[2]/n
            if n>1:
                sTEMP = math.sqrt((self.BaTe[3]/n - TEMP**2)/(n-1)/n)
                sP = math.sqrt((self.BaTe[4]/n - P**2)/(n-1)/n)
                return (P, TEMP, sP, sTEMP)
            return (P, TEMP, 0, 0)

    def __str__(self):
        return "T=%.1f°C P=%.1fmbar" % self.mean()[:2]

def parse(l):
    return BATE().parse(l)