Pre-Market High/Low

//version=5
indicator("Pre-Market High/Low", overlay=true)

startTime = timestamp("America/New_York", year, month, dayofmonth, 04, 00)
endTime = timestamp("America/New_York", year, month, dayofmonth, 09, 30)

inPremarket = (time >= startTime and time < endTime)

var float premktHigh = na
var float premktLow = na

if inPremarket
premktHigh := na(premktHigh) ? high : math.max(premktHigh, high)
premktLow := na(premktLow) ? low : math.min(premktLow, low)

if (not inPremarket) and (time[1] >= startTime and time[1] < endTime)
premktHigh := na
premktLow := na

plot(premktHigh, title="Pre-Market High", color=color.green, linewidth=1, style=plot.style_line)
plot(premktLow, title="Pre-Market Low", color=color.red, linewidth=1, style=plot.style_line)