PineForge Tranche Partial Market Close

//@version=6
// SPDX-License-Identifier: Apache-2.0
// Copyright 2026 PineForge
// PineForge Owned Strategy: Tranche Partial Market Close
// A first objective realizes half the position through a market close.
strategy("PineForge — Tranche Partial Market Close", overlay=true,
     initial_capital=100000,
     default_qty_type=strategy.fixed, default_qty_value=4,
     pyramiding=0, commission_type=strategy.commission.percent,
     commission_value=0.05, slippage=1,
     margin_long=100, margin_short=100,
     process_orders_on_close=false, calc_on_order_fills=false)

fastLength = input.int(19, "Fast EMA Length", minval=2, group="Signal")
slowLength = input.int(58, "Slow EMA Length", minval=5, group="Signal")
atrLength = input.int(16, "ATR Length", minval=2, group="Risk")
trancheAtr = input.float(1.3, "First Tranche ATR", minval=0.2, step=0.1, group="Risk")
maximumAtrLoss = input.float(2.4, "Maximum ATR Loss", minval=0.5, step=0.1, group="Risk")

fastLine = ta.ema(close, fastLength)
slowLine = ta.ema(close, slowLength)
atrValue = ta.atr(atrLength)
enterLong = ta.crossover(fastLine, slowLine)

var bool trancheTaken = false
if strategy.position_size == 0
    trancheTaken := false

firstObjective = strategy.position_size > 0 and close >= strategy.position_avg_price + atrValue * trancheAtr
trendEnded = strategy.position_size > 0 and ta.crossunder(fastLine, slowLine)
riskExceeded = strategy.position_size > 0 and close < strategy.position_avg_price - atrValue * maximumAtrLoss

if strategy.position_size == 0 and enterLong
    strategy.entry("Tranche Long", strategy.long)
else if strategy.position_size > 0 and not trancheTaken and firstObjective
    strategy.close("Tranche Long", qty_percent=50, comment="First tranche")
    trancheTaken := true
else if strategy.position_size > 0 and (trendEnded or riskExceeded)
    strategy.close("Tranche Long", comment=riskExceeded ? "ATR risk" : "Trend ended")

plot(fastLine, "Fast EMA", color=color.blue)
plot(slowLine, "Slow EMA", color=color.orange)