Modified Directional Movement Index Strategy

/*backtest
start: 2022-09-07 00:00:00
end: 2023-09-13 00:00:00
period: 3d
basePeriod: 1d
exchanges: [{"eid":"Futures_Binance","currency":"BTC_USDT"}]
*/

//@version=4
strategy(shorttitle="DMI Modified Strategy", title="DMI Modified Strategy", overlay=true,default_qty_type=strategy.cash, default_qty_value=10000, initial_capital=10000)
// This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License https://creativecommons.org/licenses/by-sa/4.0/
// © dman103
// As promised a strategy of my DMI Modified indicator! (See link below for indicator).
// === How does it work? ===
// Instead of plotting the positive direction of +DI and negative direction for -DI, we subtract the +DI with the -DI on scales of 100 to -100.
// The result is plotted with a oscillator to identify the current trend.
// DMI Modified supports multiple moving averages (default is EMA with length of 9). You can disable moving averages smoothing in settings.

//== About the Strategy ==
// Buys when the line crosses over the Zero line.
// Sells when the line crosses under the Zero line.
// The DMI modified  strategy is pretty much clean, without any filtering besides the DMI Modified and a moving average to smooth it.
// Works best to catch a trend and more suitable for 1 hour and above time frame. Stay tuned for updates.

// == Oscillator Colors ==
// GREEN : Strong Up Trend as DMI Modified is above zero line and DMI modified is ascending.
// LIGHT GREEN: Still up trend but weakening as DMI modified is above zero but descending. 
// RED: Strong Downtrend as DMI Modified is below zero line and DMI modified is descending.
// LIGHT RED: Still down trending but weakening as DMI modified is below zero but ascending.

// == Notes ==
// Short is enabled by default.
// Can also be used to find divergences.
// Bar coloring is disabled by default

// == Links ==
// DMI modified indicator: https://www.tradingview.com/script/CbDXEyDN-DMI-Modified/
// Like if you like and Enjoy! Follow for more upcoming indicators/strategies: https://www.tradingview.com/u/dman103/#published-scripts

length = input(9, title="Length", minval=0)
smoothing_length=input(9, title="Smoothing length")
ma_select = input(title="Moving Average Type", defval="EMA", options=["NONE","SMA","SMMA" ,"EMA", "WMA", "HMA", "JMA"])
allow_short = input(true,title="Allow Short")
MA_selector(src, length) =>
    ma = 0.0
    if ma_select == "NONE"
        ma:=src
        ma
    if ma_select == "SMA"
        ma := sma(src, length)
        ma
    if ma_select == "SMMA"
        smma = float (0.0)
        smaval=sma(src, length)
        smma := na(smma[1]) ? smaval : (smma[1] * (length - 1) + src) / length
        ma := smma
    if ma_select == "EMA"
        ma := ema(src, length)
        ma

    if ma_select == "WMA"
        ma := wma(src, length)
        ma
    if ma_select == "HMA"
        ma := hma(src,length)
        ma
    if ma_select == "JMA"
        beta = 0.45*(length-1)/(0.45*(length-1)+2)
        alpha = beta
        tmp0 = 0.0, tmp1 = 0.0, tmp2 = 0.0, tmp3 = 0.0, tmp4 = 0.0
        tmp0 := (1-alpha)*src + alpha*nz(tmp0[1])
        tmp1 := (src - tmp0[0])*(1-beta) + beta*nz(tmp1[1])
        tmp2 := tmp0[0] + tmp1[0]
        tmp3 := (tmp2[0] - nz(tmp4[1]))*((1-alpha)*(1-alpha)) + (alpha*alpha)*nz(tmp3[1])
        tmp4 := nz(tmp4[1]) + tmp3[0]
        ma := tmp4
        ma
    
    ma
color_bars=input(false,title="Color bars")
//  Colors
col_grow_above = #26A69A
col_grow_below = #FFCDD2
col_fall_above = #AAFFDB
col_fall_below = #EF5350

dirmov(len,up_band,low_band) =>
	up = change(highest(up_band,len)) 
	down = -change(lowest(low_band,len))
	truerange = rma(tr, len)
	plus = fixnan(100 * rma(up > down and up > 0 ? up : 0, len) / truerange)
	minus = fixnan(100 * rma(down > up and down > 0 ? down : 0, len) / truerange)
	[plus, minus]

[plus, minus]= dirmov(length,high,low)
result= plus-minus
result:=MA_selector(result,smoothing_length)
closeStatus =  strategy.openprofit > 0 ? "win" : "lose"
colors= result > 0 and result>result[1] ? col_grow_above : result > 0 and result<result[1] ? col_fall_above : result<0 and result>result[1] ? col_grow_below : result<0 and result<result[1] ? col_fall_below : color.white
dmi=plot(result, style=plot.style_line, color=colors, linewidth=2, title="DI+-")
barcolor(color_bars ? colors : na)
zero_line=plot(0, color=color.white, title="0-Line",transp=60)
fill (dmi,zero_line,color=colors)
long =  result > 0 and result>result[1]
short = result< 0 and result<result[1]
// strategy.entry("B", true,when=long)
// strategy.entry("S",false,when=short)


//, comment=strategy.position_size<0 ? closeStatus : na)
strategy.close("short",when=long,comment=closeStatus)
strategy.close("long",when=short,comment=closeStatus)
strategy.entry("long", true, when = long)
if (allow_short)
    strategy.entry("short",false, when = short)

plotshape(crossover(result,0) ? result : na, style=shape.circle, color=color.lime,location=location.absolute,size=size.tiny,transp=65)
plotshape(crossunder(result,0) ? result : na, style=shape.circle, color=color.red,location=location.absolute,size=size.tiny,transp=65)