RSI Chart Bars

//@version=4
// RSI Candle Colors
// Author John Furr
study(title="RSI Chart Bars",overlay = true, shorttitle="RSI Bars")
color c_up = input(#00FF00, "Color Up", type = input.color)
color c_down = input(#0000FF, "Color Down", type = input.color)
color c_peak = input(#FF0000, "Color Peak", type = input.color)
peak_val = input(85, "Peak Value", type=input.integer)

src = close, len = input(14, minval=1, title="Length")
up = rma(max(change(src), 0), len)
down = rma(-min(change(src), 0), len)
rsi = down == 0 ? 100 : up == 0 ? 0 : 100 - (100 / (1 + up / down))


UpColor(value) =>
    value >= peak_val ? color.from_gradient(value, peak_val, 100, c_up, c_peak) : color.from_gradient(value, 50, peak_val, color.gray, c_up)

DownColor(value) =>
    value <= 30 ? color.from_gradient(value, 0, 30, c_peak, c_down) : color.from_gradient(value, 30, 50, c_down, color.gray)

plotColor = (rsi > 50) ? UpColor(rsi) : DownColor(rsi)
plotcandle(open, high, low, close, color=plotColor, wickcolor=plotColor, bordercolor=plotColor)