from myhdl import block, Signal, delay, always, now
import math

# subsetsum analogon using "reversible computing"
# OH 2018
cumultune          = 0
TIMESCALE          = 1e-3
SIMULATIONDURATION = 1e6
ALPHA              = 1e-2


@block
def SubsetsumAnalogon(tones_,harmonicdistortion_, targetsum_):
    tones = tones_
    harmonicdistortion = harmonicdistortion_ # [a,b,c,..] = a*X + b*X^2 + c* X^3 + ....
    targetsum = targetsum_
    
    
    clk   = Signal(0)
    
    def setTones( tones_):
      tones = tones_

    @always(delay(10))
    def drive_clk():
        clk.next = not clk

    @always(clk.posedge)
    def timedomain():
        global cumultune 
        t = now()*TIMESCALE
        
        x = 0
        for tone in tones:
          x = x + math.sin(tone*t)
        
        y = 0   
        n = len(harmonicdistortion)
        for order in range(0,n):
          y = y + (harmonicdistortion[order])*math.pow(x,order+1)
          
        tuning  = math.sin( targetsum * t ) * y + math.cos( targetsum * t ) * y
        #cumultune = (ALPHA)* tuning + (1.-ALPHA)*cumultune 
        cumultune = cumultune  + tuning
        
        # (1)timebase         (2)unmixed  
        # (3)distorted signal (4) power of tuning frequency (target detection) 
        print("%g %g %g %g" % (t,x,y,cumultune))

    return drive_clk, timedomain

inst = SubsetsumAnalogon([ 31,11, 7],[1,1] , 17)
inst.run_sim(SIMULATIONDURATION)