Pivot Levels

//@version=6
// Example script bundled with DegenView. Edit it freely.
// Draws a horizontal line from every confirmed swing high (resistance) and swing
// low (support), and keeps only the most recent few of each. A pivot is confirmed
// "right bars" after it happens, so levels appear with that delay.
indicator("Pivot Levels", overlay = true)

leftBars = input.int(10, "Left bars", minval = 1, group = "Pivots")
rightBars = input.int(10, "Right bars", minval = 1, group = "Pivots")
keep = input.int(5, "Levels to keep per side", minval = 1, maxval = 20, group = "Display")
resistanceColor = input.color(color.red, "Resistance", group = "Display")
supportColor = input.color(color.green, "Support", group = "Display")

var array<line> resistance = array.new<line>()
var array<line> support = array.new<line>()
var array<label> tags = array.new<label>()

// Draws one level, then deletes the oldest ones beyond the cap.
addLevel(array<line> levels, float price, color levelColor, int pivotBar) =>
    levels.push(line.new(pivotBar, price, bar_index, price, extend = extend.right, color = levelColor))
    tags.push(label.new(pivotBar, price, str.tostring(price, format.mintick), style = label.style_label_down, color = levelColor, textcolor = color.white, size = size.small))
    if levels.size() > keep
        line.delete(levels.shift())
        label.delete(tags.shift())

pivotHigh = ta.pivothigh(high, leftBars, rightBars)
pivotLow = ta.pivotlow(low, leftBars, rightBars)

if not na(pivotHigh)
    addLevel(resistance, pivotHigh, resistanceColor, bar_index - rightBars)
if not na(pivotLow)
    addLevel(support, pivotLow, supportColor, bar_index - rightBars)