2 colour MACD

study(shorttitle = "MACD WAVE TRADER", title = "2 colour MACD")
fastMA = input(title="Fast moving average", type = integer, defval = 12, minval = 7)
slowMA = input(title="Slow moving average", type = integer, defval = 26, minval = 7)
lastColor = yellow
[currMacd,_,_] = macd(close[0], fastMA, slowMA, 9)
[prevMacd,_,_] = macd(close[1], fastMA, slowMA, 9)
plotColor = currMacd > 0
? currMacd > prevMacd ? white : maroon
: currMacd < prevMacd ? maroon : white
plot(currMacd, style = histogram, color = plotColor, linewidth = 3)
plot(0, title = "Zero line", linewidth = 1, color = gray)