Supertrend - Dynamic Trend Follower

// This Pine Script™ code is subject to the terms of the Mozilla Public License 2.0
// © TradingTools

//@version=5
strategy("Supertrend - Dynamic Trend Follower", overlay=true, default_qty_type=strategy.percent_of_equity, default_qty_value=100)

// ─── Inputs ───
stFactor1       = input.float(3.0, "Supertrend Factor 1", step=0.1, group="Supertrend")
stPeriod1       = input.int(10, "Supertrend Period 1", group="Supertrend")
stFactor2       = input.float(2.0, "Supertrend Factor 2 (Fast)", step=0.1, group="Supertrend")
stPeriod2       = input.int(7, "Supertrend Period 2 (Fast)", group="Supertrend")
useDualST       = input.bool(true, "Use Dual Supertrend Confirmation", group="Supertrend")
emaLength       = input.int(200, "Trend Filter EMA", group="Filters")
useTrendFilter  = input.bool(false, "Use EMA Trend Filter", group="Filters")
atrLength       = input.int(14, "ATR Length", group="Risk Management")
atrMult         = input.float(2.0, "ATR Multiplier for SL", step=0.1, group="Risk Management")
trailAtrMult    = input.float(2.5, "Trailing Stop ATR Mult", step=0.1, group="Risk Management")

// ─── Supertrend 1 (Primary) ───
[st1, dir1] = ta.supertrend(stFactor1, stPeriod1)
bullST1 = dir1 < 0
bearST1 = dir1 > 0

// ─── Supertrend 2 (Fast) ───
[st2, dir2] = ta.supertrend(stFactor2, stPeriod2)
bullST2 = dir2 < 0
bearST2 = dir2 > 0

// ─── Trend Filter ───
emaVal = ta.ema(close, emaLength)
emaBull = useTrendFilter ? close > emaVal : true
emaBear = useTrendFilter ? close < emaVal : true

// ─── ATR ───
atrVal = ta.atr(atrLength)

// ─── Entry Conditions ───
// Dual: both supertrends must agree
// Single: only primary supertrend
stFlipLong  = bullST1 and not bullST1[1]  // primary flipped bullish
stFlipShort = bearST1 and not bearST1[1]  // primary flipped bearish

dualBull = useDualST ? (bullST1 and bullST2) : bullST1
dualBear = useDualST ? (bearST1 and bearST2) : bearST1

longCondition  = stFlipLong and (useDualST ? bullST2 : true) and emaBull
shortCondition = stFlipShort and (useDualST ? bearST2 : true) and emaBear

// ─── Execute Trades ───
if longCondition and strategy.position_size <= 0
    sl = close - atrVal * atrMult
    strategy.entry("ST Long", strategy.long)
    strategy.exit("ST Long Exit", "ST Long", stop=sl, trail_offset=atrVal * trailAtrMult, trail_points=atrVal * trailAtrMult)

if shortCondition and strategy.position_size >= 0
    sl = close + atrVal * atrMult
    strategy.entry("ST Short", strategy.short)
    strategy.exit("ST Short Exit", "ST Short", stop=sl, trail_offset=atrVal * trailAtrMult, trail_points=atrVal * trailAtrMult)

// ─── Exit on Supertrend Flip ───
if strategy.position_size > 0 and bearST1
    strategy.close("ST Long", comment="ST Flip")
if strategy.position_size < 0 and bullST1
    strategy.close("ST Short", comment="ST Flip")

// ─── Plotting ───
plot(bullST1 ? st1 : na, "Supertrend 1 Bull", color=color.new(color.green, 0), linewidth=2, style=plot.style_linebr)
plot(bearST1 ? st1 : na, "Supertrend 1 Bear", color=color.new(color.red, 0), linewidth=2, style=plot.style_linebr)

plot(useDualST and bullST2 ? st2 : na, "Supertrend 2 Bull", color=color.new(color.green, 50), linewidth=1, style=plot.style_linebr)
plot(useDualST and bearST2 ? st2 : na, "Supertrend 2 Bear", color=color.new(color.red, 50), linewidth=1, style=plot.style_linebr)

plot(useTrendFilter ? emaVal : na, "EMA Filter", color=color.new(color.gray, 40), linewidth=1)

bgcolor(dualBull ? color.new(color.green, 93) : dualBear ? color.new(color.red, 93) : na, title="Dual ST Direction")

plotshape(longCondition, title="Long", location=location.belowbar, style=shape.triangleup, color=color.green, size=size.small)
plotshape(shortCondition, title="Short", location=location.abovebar, style=shape.triangledown, color=color.red, size=size.small)

// ─── Alerts ───
alertcondition(longCondition, title="Supertrend Long", message="Supertrend: Bullish flip — Long entry")
alertcondition(shortCondition, title="Supertrend Short", message="Supertrend: Bearish flip — Short entry")