Pinescript Indicator for Tradingview

I want a box drawn like this on certain candles all the way across until the candle trades into it. code is something like, if 4 down red candles = true and there is less than 3 green candles before 4 more red down candles then draw box from high of first green candle to low of last green candle ,then alert opposite is true for bullish example. I want to use this for back testing and see how well it performs when i visually look back in the past charts