// This source code is subject to the terms of the Mozilla Public License 2.0 at https://mozilla.org/MPL/2.0/
// © yashp1334

//@version=4
//@version=4
//Script by MrBadger
//Free for public consumption
//There is very little original here, the idea is discussed in the underground traders alliance and 
// was (apparently) the basis of what was at one time myfxbooks most profitable strategy.
// I can't find the original video that was floating around on youtube, but if i find it again, i'll link it here.
//
// This is bascially just the TV default envelope code copied and modified. 
// THe idea is to have an envelope based on a low length, exponential basis. Then to manually "tune"
// the percent input so that the envelopes engulf most bars.
//
// Anything that protudes beyond that level, especially at key levels, is likely to revert back to the ema.
// Bear in mind, a run away trend will also push past the envelopes and continue running for several (3-5) bars
// so, use it mindfully andthoughfully with all the usual cautions about risk management.


strategy(title="Mean recursion envelop", shorttitle="MRE", overlay=true)

len = input(5)
calibrationFactor = input(.7)
rangeLookback = input(100)

range = sma(tr(true),rangeLookback) * .7

src = input(close, title="Source")
exponential = input(false)

basis = exponential ? ema(src, len) : sma(src, len)
percent = range/basis *100

k = percent/100.0
upper = basis * (1 + k)
lower = basis * (1 - k)
buySignal = crossover(src, lower)
sellSignal = crossunder(src, upper)

//INTRADAY
s=input(title="INTRA DAY TRADE SESSION",type=input.session,defval="0915-1450")
st=time(timeframe.period,s)
e=input(title="END SESSION",type=input.session,defval="1515-1520")
et=time(timeframe.period,e)
quant=input(title="Trade Quantity",defval=1)

//adding stoploss and target option
ut=input(defval=false,title="USE TARGET")
us=input(defval=false,title="USE STOPLOSS")
tar=input(defval=10.0,title="TARGET IN RS")
stop=input(defval=7.0,title="STOP LOSS IN RS")
tar:=tar/syminfo.mintick
stop:=stop/syminfo.mintick

//setting automated alerts required by apibridge
lxse="TYPE: LX" + " :SYMBOL: " + syminfo.ticker + " :QTY: " + tostring(quant) + " :TYPE:SE " + " :SYMBOL: " + syminfo.ticker + " :QTY: " + tostring(quant)

sxle="TYPE: SX" + " :SYMBOL: " + syminfo.ticker + " :QTY: " + tostring(quant) + " :TYPE:LE " + " :SYMBOL: " + syminfo.ticker + " :QTY: " + tostring(quant)

le="TYPE:LE " + " :SYMBOL: " + syminfo.ticker + " :QTY: " + tostring(quant)

lx="TYPE:LX " + " :SYMBOL: " + syminfo.ticker + " :QTY: " + tostring(quant)

se="TYPE:SE " + " :SYMBOL: " + syminfo.ticker + " :QTY: " + tostring(quant)

sx="TYPE:SX " + " :SYMBOL: " + syminfo.ticker + " :QTY: " + tostring(quant)
if(buySignal and st and strategy.position_size==0)
    strategy.entry("BUY",strategy.long,comment=le)
if(sellSignal and st and strategy.position_size==0)
    strategy.entry("SELL",strategy.short,comment=se)
if(buySignal and st and strategy.position_size!=0)
    strategy.entry("BUY",strategy.long,comment=sxle)
if(sellSignal and st and strategy.position_size!=0)
    strategy.entry("SELL",strategy.short,comment=lxse)
    
if(ut==true and us==false)
    strategy.exit(id="LX",from_entry="BUY",profit=tar,comment=lx)
    strategy.exit(id="SX",from_entry="SELL",profit=tar,comment=sx)
if(us==true and ut==false)
    strategy.exit(id="LX",from_entry="BUY",loss=stop,comment=lx)
    strategy.exit(id="SX",from_entry="SELL",loss=stop,comment=sx)
    
if(ut==true and us==true)
    strategy.exit(id="LX",from_entry="BUY",profit=tar,loss=stop,comment=lx)
    strategy.exit(id="SX",from_entry="SELL",profit=tar,loss=stop,comment=sx)
strategy.close(id="BUY",when=et,comment=lx)
strategy.close(id="SELL",when=et,comment=sx)


plot(basis, "Basis", color=#FF6A00)
u = plot(upper, "Upper", color=#0094FF)
l = plot(lower, "Lower", color=#0094FF)
fill(u, l, color=#0094FF, transp=95, title="Background")
alertcondition(high>upper,"Enveloped breached", "look for reversion to mean")
alertcondition(low<lower,"Enveloped breached", "look for reversion to mean")