Relative Strength Index

//version=6
indicator(title="Relative Strength Index", shorttitle="RSI", format=format.price, precision=2, timeframe="", timeframe_gaps=true)

// RSI Settings
rsiLengthInput = input.int(14, minval=1, title="RSI Length", group="RSI Settings")
rsiSourceInput = input.source(close, "Source", group="RSI Settings")
calculateDivergence = input.bool(false, title="Calculate Divergence", group="RSI Settings", display = display.data_window, tooltip = "Calculating divergences is needed in order for divergence alerts to fire.")

// RSI Calculation
change = ta.change(rsiSourceInput)
up = ta.rma(math.max(change, 0), rsiLengthInput)
down = ta.rma(-math.min(change, 0), rsiLengthInput)
rsi = down == 0 ? 100 : up == 0 ? 0 : 100 - (100 / (1 + up / down))

// Smoothing MA inputs
GRP = "Smoothing"
TT_BB = "Only applies when 'SMA + Bollinger Bands' is selected. Determines the distance between the SMA and the bands."
maTypeInput = input.string("SMA", "Type", options = ["None", "SMA", "SMA + Bollinger Bands", "EMA", "SMMA (RMA)", "WMA", "VWMA"], group = GRP, display = display.data_window)
maLengthInput = input.int(14, "Length", group = GRP, display = display.data_window)
bbMultInput = input.float(2.0, "BB StdDev", minval = 0.001, maxval = 50, step = 0.5, tooltip = TT_BB, group = GRP, display = display.data_window)
var enableMA = maTypeInput != "None"
var isBB = maTypeInput == "SMA + Bollinger Bands"

// Smoothing MA Calculation
ma(source, length, MAtype) =>
switch MAtype
"SMA" => ta.sma(source, length)
"SMA + Bollinger Bands" => ta.sma(source, length)
"EMA" => ta.ema(source, length)
"SMMA (RMA)" => ta.rma(source, length)
"WMA" => ta.wma(source, length)
"VWMA" => ta.vwma(source, length)

// Calculate MA
smoothingMA = enableMA ? ma(rsi, maLengthInput, maTypeInput) : na

// Define RSI color based on position relative to MA
rsiColor = enableMA ? (rsi > smoothingMA ? color.green : color.red) : (rsi > rsi[1] ? color.green : color.red)

// Plot RSI with dynamic color
rsiPlot = plot(rsi, "RSI", color = rsiColor)

// Horizontal lines
rsiUpperBand = hline(70, "RSI Upper Band (70)", color=#787B86, linestyle=hline.style_solid)
rsiUpperMidBand = hline(60, "RSI Upper Mid Band (60)", color=color.new(#787B86, 30), linestyle=hline.style_dashed)
midline = hline(50, "RSI Middle Band (50)", color=color.new(#787B86, 50))
rsiLowerMidBand = hline(40, "RSI Lower Mid Band (40)", color=color.new(#787B86, 30), linestyle=hline.style_dashed)
rsiLowerBand = hline(30, "RSI Lower Band (30)", color=#787B86, linestyle=hline.style_solid)

// Fills
fill(rsiUpperBand, rsiUpperMidBand, color=color.new(color.green, 90), title="Extreme Overbought Zone")
fill(rsiUpperMidBand, midline, color=color.new(color.green, 95), title="Overbought Zone")
fill(midline, rsiLowerMidBand, color=color.new(color.red, 95), title="Oversold Zone")
fill(rsiLowerMidBand, rsiLowerBand, color=color.new(color.red, 90), title="Extreme Oversold Zone")

midLinePlot = plot(50, color = na, editable = false, display = display.none)
fill(rsiPlot, midLinePlot, 100, 70, top_color = color.new(color.green, 0), bottom_color = color.new(color.green, 100), title = "Overbought Gradient Fill")
fill(rsiPlot, midLinePlot, 30, 0, top_color = color.new(color.red, 100), bottom_color = color.new(color.red, 0), title = "Oversold Gradient Fill")

// Smoothing MA plots
smoothingStDev = isBB ? ta.stdev(rsi, maLengthInput) * bbMultInput : na
plot(smoothingMA, "RSI-based MA", color=color.yellow, display = enableMA ? display.all : display.none, editable = enableMA)
bbUpperBand = plot(smoothingMA + smoothingStDev, title = "Upper Bollinger Band", color=color.green, display = isBB ? display.all : display.none, editable = isBB)
bbLowerBand = plot(smoothingMA - smoothingStDev, title = "Lower Bollinger Band", color=color.green, display = isBB ? display.all : display.none, editable = isBB)
fill(bbUpperBand, bbLowerBand, color= isBB ? color.new(color.green, 90) : na, title="Bollinger Bands Background Fill", display = isBB ? display.all : display.none, editable = isBB)

// Divergence (unchanged)
lookbackRight = 5
lookbackLeft = 5
rangeUpper = 60
rangeLower = 5
bearColor = color.red
bullColor = color.green
textColor = color.white
noneColor = color.new(color.white, 100)

_inRange(cond) =>
bars = ta.barssince(cond)
rangeLower <= bars and bars <= rangeUpper

plFound = false
phFound = false
bullCond = false
bearCond = false
rsiLBR = rsi[lookbackRight]

if calculateDivergence
plFound := not na(ta.pivotlow(rsi, lookbackLeft, lookbackRight))
plFoundPrev = plFound[1]
inRangeBull = _inRange(plFoundPrev)
rsiHL = rsiLBR > ta.valuewhen(plFound, rsiLBR, 1) and inRangeBull
lowLBR = low[lookbackRight]
priceLL = lowLBR < ta.valuewhen(plFound, lowLBR, 1)
bullCond := priceLL and rsiHL and plFound

phFound := not na(ta.pivothigh(rsi, lookbackLeft, lookbackRight))
phFoundPrev = phFound[1]
inRangeBear = _inRange(phFoundPrev)
rsiLH = rsiLBR < ta.valuewhen(phFound, rsiLBR, 1) and inRangeBear
highLBR = high[lookbackRight]
priceHH = highLBR > ta.valuewhen(phFound, highLBR, 1)
bearCond := priceHH and rsiLH and phFound

plot(plFound ? rsiLBR : na, offset = -lookbackRight, title = "Regular Bullish", linewidth = 2, color = (bullCond ? bullColor : noneColor), display = display.pane, editable = calculateDivergence)
plotshape(bullCond ? rsiLBR : na, offset = -lookbackRight, title = "Regular Bullish Label", text = " Bull ", style = shape.labelup, location = location.absolute, color = bullColor, textcolor = textColor, display = display.pane, editable = calculateDivergence)
plot(phFound ? rsiLBR : na, offset = -lookbackRight, title = "Regular Bearish", linewidth = 2, color = (bearCond ? bearColor : noneColor), display = display.pane, editable = calculateDivergence)
plotshape(bearCond ? rsiLBR : na, offset = -lookbackRight, title = "Regular Bearish Label", text = " Bear ", style = shape.labeldown, location = location.absolute, color = bearColor, textcolor = textColor, display = display.pane, editable = calculateDivergence)

alertcondition(bullCond, title='Regular Bullish Divergence', message="Found a new Regular Bullish Divergence, `Pivot Lookback Right` number of bars to the left of the current bar.")
alertcondition(bearCond, title='Regular Bearish Divergence', message='Found a new Regular Bearish Divergence, `Pivot Lookback Right` number of bars to the left of the current bar.')