Custom Session OHL

//@version=5
indicator("Custom Session OHL", shorttitle = "CUST OHL", overlay=true)

my_session = input.session("0830-0930", title='Custom Session')


var color color_open = input.color(color.yellow, "Open", inline = "O")
var bool extend_open = input.bool(true, "Extend", inline = "O")
var string text_open = input.string("Open", "", inline = "O")

var color color_high = input.color(color.blue, "High", inline = "H")
var bool extend_high = input.bool(true, "Extend", inline = "H")
var string text_high = input.string("High", "", inline = "H")

var color color_low = input.color(color.orange, "Low", inline = "L")
var bool extend_low = input.bool(true, "Extend", inline = "L")
var string text_low = input.string("Low", "", inline = "L")

var int label_offset = input.int(50, "Label Offset")

in_session = time(timeframe.period, my_session)

is_new_session(res, sess) =>
    t = time(res, sess)
    na(t[1]) and not na(t) or t[1] < t

new_session = is_new_session("1440", my_session)

is_newbar(res,sess) =>
    t = time(res,sess)
    not na(t) and (na(t[1]) or t > t[1])
new = (is_newbar("1440", my_session) ? 1 : 0)

var float reg_open = na
reg_open := new_session ? open : in_session ? reg_open[1] : (extend_open ? reg_open[1] : na)
plot_open = plot(reg_open, style = plot.style_circles, linewidth=1, color=color_open, title="open")

var float reg_high = close
var float reg_low = close
reg_high := new_session ? high : in_session ? math.max(high, reg_high[1]) : (extend_high ? reg_high[1] : na)
reg_low := new_session ? low : in_session ? math.min(low, reg_low[1]) : (extend_low ? reg_low[1] : na)
plot(reg_high, style=plot.style_circles, color=color_high, linewidth=1, title="high")
plot(reg_low, style=plot.style_circles, color=color_low, linewidth=1, title="low")

var label_open = label.new(na, na, text = text_open, style = label.style_none, textcolor = color_open)
label.set_x(label_open, bar_index + label_offset)
label.set_y(label_open, reg_open[0])

var label_high = label.new(na, na, text = text_high, style = label.style_none, textcolor = color_high)
label.set_x(label_high, bar_index + label_offset)
label.set_y(label_high, reg_high[0])

var label_low = label.new(na, na, text = text_low, style = label.style_none, textcolor = color_low)
label.set_x(label_low, bar_index + label_offset)
label.set_y(label_low, reg_low[0])