Convert pine script to afl amibroker -- 2

// This simple indicator gives you a bias on the market that can be used as a filter, an entry indicator for pullbacks,...
//
// Enjoy!
// JD.
//
// #NotTradingAdvice
// #DYOR

study("RSI direction bias - JD")
src=input(ohlc4,title="source")
len=input(14,title="rsi length")
top_level=input(60,title="top level")
bottom_level=input(40,title="bottom level")
color_bars=input(false,title="color bars?")
var int bias=1
rsi_val=rsi(src,len)
if crossover(rsi_val,top_level)
bias:=1
if crossunder(rsi_val,bottom_level)
bias:=-1
bias_line=bias==1?bottom_level:top_level
bias_color=bias==1?color.green:color.red
p1=plot(bias_line,color=bias_color)
p2=plot(rsi_val,color=bias_color)
p3=plot(bias==1 and rsi_val<=top_level?top_level:na,style=plot.style_linebr,color=color.yellow,transp=60,offset=0)
p4=plot(bias==-1 and rsi_val>=bottom_level?bottom_level:na,style=plot.style_linebr,color=color.yellow,transp=60,offset=0)
fill(p1,p2,color=bias_color)
fill(p3,p2,color=color.red)
fill(p4,p2,color=color.green)
bcol=
bias==1?
rsi_val<=top_level?color.yellow:color.green:
rsi_val>=bottom_level?color.maroon:color.red
barcolor(bcol)