#!/usr/bin/python3
from time import *
CTlong = 20              # 0 .. n-1 trend values
CTwide = 5                # columns TIME, PV, SP, OV, MD
CT_PID = [[0.0 for x in range(CTlong)] for y in range(CTwide)]       #print(Matrix)
TI = 0
PV = 1
SP = 2
OV = 3
MD = 4
CTfill = True                                                       # make a ring buffer
CTrec = -1
def CTcount():
    global CTlong, CTrec
    CTrec = CTrec + 1
    if CTrec == CTlong:
        CTrec = 0
        CTfill = False
    return  CTrec

def CTpoint(i):
    global CTlong, CTrec
    CTlist = CTrec+1+i
    if CTlist >= CTlong:
        CTlist = CTlist - CTlong
    return CTlist

def CT_PID_save(PVval,SPval,OVval,MDval):
    CT_PID[TI][CTcount()] = localtime(time())           # create time stamp
    CT_PID[PV][CTrec] = PVval
    CT_PID[SP][CTrec] = SPval
    CT_PID[OV][CTrec] = OVval
    CT_PID[MD][CTrec] = MDval
    
def CT_PID_make(counts):                      # make up data and store ringbuffer
    PVval=-1.0
    PVdel=1.0
    for i in range(0 , counts ):
        PVval=PVval+PVdel
        SPval=50.0
        OVval=(PVval-SPval)*0.1
        MDval = 2.0
        CT_PID_save(PVval,SPval,OVval,MDval)
    print("made ",counts," records and stored last ",CTlong)
        
def CT_PID_print():
    print(" i, p,  M[TI]              ,   M[PV],     M[SP],     M[OV],    M[MD] ")
    for i in range(0,CTlong):
        fTI = CT_PID[TI][CTpoint(i)]
        if fTI == 0.0: fTI = gmtime(i)            # 1970-01-01 00:00:00 + i(sec)
        Tstr=strftime("%Y-%m-%d %H:%M:%S",fTI)
        fPV = CT_PID[PV][CTpoint(i)]
        fSP = CT_PID[SP][CTpoint(i)]
        fOV = CT_PID[OV][CTpoint(i)]
        fMD = CT_PID[MD][CTpoint(i)]
        #    print ("%2d, %8.2f, %2d, %s, %8.2f" % (i,CT_PID[PV][i],CTpoint(i),Tstr,CT_PID[PV][CTpoint(i)] ) )
        print ("%2d, %2d, %s, %8.2f, %8.2f, %8.2f, %8.2f" % (i,CTpoint(i),Tstr,fPV,fSP,fOV,fMD ) )

CT_PID_make(10)
CT_PID_print()