convert a small TradingView Incicator(Volume Flow Indicator) into Thinkorswim Script

study(title = "Volume Flow Indicator [LazyBear]", shorttitle="VFI_LB")

length = input(130, title="VFI length")
coef = input(0.2)
vcoef = input(2.5, title="Max. vol. cutoff")
signalLength=input(5)
smoothVFI=input(false, type=bool)

ma(x,y) => smoothVFI ? sma(x,y) : x

typical=hlc3
inter = log( typical ) - log( typical[1] )
vinter = stdev(inter, 30 )
cutoff = coef * vinter * close
vave = sma( volume, length )[1]
vmax = vave * vcoef
vc = iff(volume < vmax, volume, vmax) //min( volume, vmax )
mf = typical - typical[1]
vcp = iff( mf > cutoff, vc, iff ( mf < -cutoff, -vc, 0 ) )

vfi = ma(sum( vcp , length )/vave, 3)
vfima=ema( vfi, signalLength )
d=vfi-vfima

plot(0, color=gray, style=3)
showHisto=input(false, type=bool)
plot(showHisto ? d : na, style=histogram, color=gray, linewidth=3, transp=50)
plot( vfima , title="EMA of vfi", color=orange)
plot( vfi, title="vfi", color=green,linewidth=2)