Improved Stoch RSI + Supertrend Filter

**Script Description: Improved Stoch RSI + Supertrend Filter**

This custom TradingView indicator combines two powerful tools—Stochastic RSI and Supertrend—to generate high-probability trade signals. It is designed for traders who prefer clear, filtered entries based on momentum and trend direction.

### Core Logic:

1. **Stochastic RSI Crossovers:**

* The indicator calculates a smoothed Stochastic RSI using user-defined lengths and smoothing parameters.
* Signals are only considered when a %K/%D crossover happens in extreme zones:

* **Bullish signal**: %K crosses above %D in the **oversold** zone.
* **Bearish signal**: %K crosses below %D in the **overbought** zone.

2. **Supertrend Filter:**

* The Supertrend indicator, based on ATR, filters trades by confirming the overall trend.
* Only **bullish crossovers** are signaled when the Supertrend is green (uptrend).
* Only **bearish crossovers** are signaled when the Supertrend is red (downtrend).

### Entry Conditions:

* **Long Entry:**

* %K crosses above %D in the oversold zone.
* Supertrend confirms an uptrend.

* **Short Entry:**

* %K crosses below %D in the overbought zone.
* Supertrend confirms a downtrend.

### Visual Aids:

* Buy and sell signals are plotted with green and red labels respectively.
* The Supertrend line is also plotted, switching color based on direction.

### Alerts:

* Custom alerts are set for both long and short conditions, making this script suitable for automated or alert-driven trading setups.

This script is ideal for swing and momentum traders looking to enter trades in strong trend conditions, filtering out noise and false reversals.