Convert simple Tradingview PineScript v2 Strategy into MQL4 Expert

//@version=2

strategy(title = "RSI versus SMA", shorttitle = "RSI vs SMA", overlay = false, pyramiding = 0, default_qty_type = contracts, default_qty_value = 1, currency = currency.EUR)

// Description:
//  - It's RSI versus a Simple Moving Average.. Not sure it really needs much more description.
//  - Should not repaint - Automatically offsets by 1 bar if anything other than "open" selected as RSI source.

// === INPUTS ===
// rsi
rsiSource   = input(defval = open, title = "RSI Source")
rsiLength   = input(defval = 8, title = "RSI Length", minval = 1)
// sma
maLength    = input(defval = 34, title = "MA Period", minval = 1)
// invert trade direction
tradeInvert = input(defval = false, title = "Invert Trade Direction?")
// risk management
useStop     = input(defval = false, title = "Use Initial Stop Loss?")
slPoints    = input(defval = 25, title = "Initial Stop Loss Points", minval = 1)
useTS       = input(defval = true, title = "Use Trailing Stop?")
tslPoints   = input(defval = 120, title = "Trail Points", minval = 1)
useTSO      = input(defval = false, title = "Use Offset For Trailing Stop?")
tslOffset   = input(defval = 20, title = "Trail Offset Points", minval = 1)
// === /INPUTS ===

// === BASE FUNCTIONS ===
// delay for direction change actions
switchDelay(exp, len) =>
    average = len >= 2 ? sum(exp, len) / len : exp[1]
    up      = exp > average
    down    = exp < average
    state   = up ? true : down ? false : up[1]
// === /BASE FUNCTIONS ===

// === SERIES and VAR ===
// rsi
shunt = rsiSource == open ? 0 : 1
rsiUp = rma(max(change(rsiSource[shunt]), 0), rsiLength)
rsiDown = rma(-min(change(rsiSource[shunt]), 0), rsiLength)
rsi = (rsiDown == 0 ? 100 : rsiUp == 0 ? 0 : 100 - (100 / (1 + rsiUp / rsiDown))) - 50 // shifted 50 points to make 0 median
// sma of rsi
rsiMa   = sma(rsi, maLength)
// self explanatory..
tradeDirection = tradeInvert ? 0 <= rsiMa ? true : false : 0 >= rsiMa ? true : false
// === /SERIES ===

// === PLOTTING ===
barcolor(color = tradeDirection ? green : red, title = "Bar Colours")
// hlines
medianLine  = hline(0, title = 'Median', color = #996600, linestyle = dotted, linewidth = 1)
limitUp     = hline(25, title = 'Limit Up', color = silver, linestyle = dotted, linewidth = 1)
limitDown   = hline(-25, title = 'Limit Down', color = silver, linestyle = dotted, linewidth = 1)
// rsi and ma
rsiLine     = plot(rsi, title = 'RSI', color = purple, linewidth = 2, style = line, transp = 50)
areaLine    = plot(rsiMa, title = 'Area MA', color = silver, linewidth = 1, style = area, transp = 70)
// === /PLOTTING ===

goLong() => not tradeDirection[1] and tradeDirection
killLong() => tradeDirection[1] and not tradeDirection
strategy.entry(id = "Buy", long = true, when = goLong())
strategy.close(id = "Buy", when = killLong())

goShort() => tradeDirection[1] and not tradeDirection
killShort() => not tradeDirection[1] and tradeDirection
strategy.entry(id = "Sell", long = false, when = goShort())
strategy.close(id = "Sell", when = killShort())

if (useStop)
    strategy.exit("XSL", from_entry = "Buy", loss = slPoints)
    strategy.exit("XSS", from_entry = "Sell", loss = slPoints)
// if we're using the trailing stop
if (useTS and useTSO) // with offset
    strategy.exit("XSL", from_entry = "Buy", trail_points = tslPoints, trail_offset = tslOffset)
    strategy.exit("XSS", from_entry = "Sell", trail_points = tslPoints, trail_offset = tslOffset)
if (useTS and not useTSO) // without offset
    strategy.exit("XSL", from_entry = "Buy", trail_points = tslPoints)
    strategy.exit("XSS", from_entry = "Sell", trail_points = tslPoints)

This script should have the following functions:

-ability to backtest

-LotSize input - how much I want to use for trades, from 0,01 to 0,1 to 1 (of course I can set what I what I want e.g. 0,3 as well and so on)

-Automatic trade execution

SourceCode included of course