EMA Bollinger Bands with FVG Boxes Outside

//version=6
indicator("EMA Bollinger Bands with FVG Boxes Outside", overlay=true)

// Input parameters
length = input.int(50, "EMA Length")
mult = input.float(2.0, "Bollinger Band Multiplier", step=0.1)
fvg_color_up = input.color(color.new(color.green, 80), "FVG Up Box Color")
fvg_color_down = input.color(color.new(color.red, 80), "FVG Down Box Color")
extension_length = input.int(3, "Box Extension Bars to Right", minval=0, maxval=50)

// Calculate EMA and EMA-based Bollinger Bands
ema_val = ta.ema(close, length)
dev = mult * ta.stdev(close, length)
upper_band = ema_val + dev
lower_band = ema_val - dev

// Plot EMA Bollinger Bands
plot(upper_band, "Upper Band", color=color.blue)
plot(ema_val, "EMA", color=color.orange)
plot(lower_band, "Lower Band", color=color.blue)

// Function to detect Fair Value Gaps (FVG)
// Bullish FVG when low of current bar > high of bar 2 bars ago
fvg_up = low > high[2]
// Bearish FVG when high of current bar < low of bar 2 bars ago
fvg_down = high < low[2]

// Check if FVG is outside Bollinger Bands
fvg_up_outside = fvg_up and low > upper_band
fvg_down_outside = fvg_down and high < lower_band

// Draw bullish FVG box, extended to the right by extension_length bars
if (fvg_up_outside)
box.new(left=bar_index[2], top=high[2], right=bar_index + extension_length, bottom=low, bgcolor=fvg_color_up, border_color=fvg_color_up)

// Draw bearish FVG box, extended to the right by extension_length bars
if (fvg_down_outside)
box.new(left=bar_index[2], top=low[2], right=bar_index + extension_length, bottom=high, bgcolor=fvg_color_down, border_color=fvg_color_down)