EMA Engulfing Pine Strategy

I need a clean, fully-commented Pine Script strategy that I can drop straight into TradingView, press “Add to chart,” and start back-testing right away. The logic is simple but I want it coded robustly:... (Budget: ₹1500 - ₹12500 INR, Jobs: Algorithmic Trading, Backtesting, Google Chrome, JavaScript, PHP, Pine Script, Software Architecture, TradingView)