Fixed Zone Flow (ABO SALTAN)

//version=5
indicator("Fixed Zone Flow (ABO SALTAN)", overlay=false)

// ===== INPUTS =====
lenFast = input.int(10, "Fast Length")
lenSlow = input.int(21, "Slow Length")
signal = input.int(4, "Signal Smooth")

buyLevel = input.int(-60, "BUY Level (Fixed)")
sellLevel = input.int(60, "SELL Level (Fixed)")

// ===== CORE =====
price = hlc3
basis = ta.ema(price, lenFast)
dev = ta.ema(math.abs(price - basis), lenFast)
ci = (price - basis) / (0.015 * dev)

fzf = ta.ema(ci, lenSlow)
sig = ta.sma(fzf, signal)

// ===== FIXED BUY / SELL =====
fixedBuy = ta.crossover(fzf, buyLevel)
fixedSell = ta.crossunder(fzf, sellLevel)

// ===== PLOTS =====
plot(fzf, title="FZF", color=color.aqua, linewidth=2)
plot(sig, title="Signal", color=color.orange)

hline(buyLevel, "FIXED BUY", color=color.green, linestyle=hline.style_dashed)
hline(sellLevel, "FIXED SELL", color=color.red, linestyle=hline.style_dashed)
hline(0, "Zero", color=color.gray)

// ===== SIGNAL MARKERS =====
plotshape(fixedBuy, title="BUY",
style=shape.labelup,
location=location.bottom,
color=color.lime,
text="BUY",
textcolor=color.black)

plotshape(fixedSell, title="SELL",
style=shape.labeldown,
location=location.top,
color=color.red,
text="SELL",
textcolor=color.white)