Extremes Clock

// This work is licensed under the Mozilla Public License 2.0
// https://mozilla.org/MPL/2.0/
// AXIS Desk

//@version=6
indicator("AXIS Extremes Clock", "AXIS EXTREMES", overlay = true, max_lines_count = 500, max_labels_count = 500)

// =============================================================================
//  AXIS EXTREMES CLOCK
//
//  The chart already tells you WHERE the session high and low are.
//  It does not tell you HOW LONG they have stood.
//
//  This draws each session's high and low as a ray from the bar that made it,
//  and puts a running clock on it. The ray strengthens as the extreme ages, so
//  a high that has held all morning does not look like one printed a minute ago.
//
//  That is the whole study. It forecasts nothing and it signals nothing.
//  It is a clock on something the chart already knows.
// =============================================================================


// ---- inputs -----------------------------------------------------------------
g_s   = "Session"
i_sess = input.session("0930-1600", "Session",  group = g_s, tooltip = "The window whose high and low are tracked. Regular US cash hours by default. Use 1800-1700 for a full Globex day.")
i_tz   = input.string("America/New_York", "Timezone", options = ["America/New_York", "America/Chicago", "America/Los_Angeles", "Europe/London", "Europe/Berlin", "Asia/Tokyo", "Asia/Shanghai", "Australia/Sydney", "UTC"], group = g_s)

g_d   = "Display"
i_hist  = input.int(5, "Sessions kept", minval = 1, maxval = 60, group = g_d, tooltip = "How many past sessions stay drawn.")
i_lbl   = input.bool(true,  "Clock labels on the rays", group = g_d)
i_table = input.bool(true,  "Corner readout",           group = g_d)
i_pos   = input.string("Top right", "Readout corner", options = ["Top right", "Top left", "Bottom right", "Bottom left"], group = g_d)
i_size  = input.string("Small", "Text size", options = ["Tiny", "Small", "Normal", "Large"], group = g_d)

g_a   = "Age ramp"
i_full  = input.int(180, "Full intensity at (minutes)", minval = 5, maxval = 1440, group = g_a, tooltip = "A fresh extreme draws faint and thin. It reaches full colour and full width once it has stood this long.")
i_wmin  = input.int(1, "Width when fresh", minval = 1, maxval = 4, group = g_a)
i_wmax  = input.int(3, "Width when settled", minval = 1, maxval = 4, group = g_a)

g_c   = "Colour"
i_cHi   = input.color(color.new(#2FA98A, 0), "High", group = g_c, inline = "c1")
i_cLo   = input.color(color.new(#C9705F, 0), "Low",  group = g_c, inline = "c1")
i_fade  = input.int(72, "Fade when fresh (%)", minval = 0, maxval = 95, group = g_c)


// ---- session state ----------------------------------------------------------
inSess  = not na(time(timeframe.period, i_sess, i_tz))
newSess = inSess and not inSess[1]

var float hiPx   = na
var float loPx   = na
var int   hiMs   = na
var int   loMs   = na
var int   hiBar  = na
var int   loBar  = na
var line  hiLine = na
var line  loLine = na
var label hiLab  = na
var label loLab  = na


// ---- helpers ----------------------------------------------------------------
// Elapsed milliseconds rendered as "4h 07m" / "38m". Nothing below a minute:
// a sub-minute extreme is noise and a ticking seconds field reads as precision
// this study does not have.
f_dur(int ms) =>
    int mins = na(ms) or ms < 0 ? 0 : int(math.floor(ms / 60000))
    int h    = int(math.floor(mins / 60))
    int m    = mins % 60
    h > 0 ? str.tostring(h) + "h " + str.format("{0,number,00}", m) + "m" : str.tostring(m) + "m"

// 0.0 the instant it prints, 1.0 once it has stood i_full minutes.
f_ramp(int ms) =>
    na(ms) ? 0.0 : math.min(1.0, math.max(0.0, ms / (i_full * 60000.0)))

f_size(string s) =>
    switch s
        "Tiny"   => size.tiny
        "Small"  => size.small
        "Normal" => size.normal
        =>          size.large

txtSize = f_size(i_size)


// ---- track the extremes -----------------------------------------------------
if newSess
    hiPx  := high
    loPx  := low
    hiMs  := time
    loMs  := time
    hiBar := bar_index
    loBar := bar_index

    hiLine := line.new(bar_index, high, bar_index, high, xloc = xloc.bar_index, color = i_cHi, width = i_wmin)
    loLine := line.new(bar_index, low,  bar_index, low,  xloc = xloc.bar_index, color = i_cLo, width = i_wmin)

    if i_lbl
        hiLab := label.new(bar_index, high, "", xloc = xloc.bar_index, yloc = yloc.price, style = label.style_label_left, color = #00000000, textcolor = i_cHi, size = txtSize)
        loLab := label.new(bar_index, low,  "", xloc = xloc.bar_index, yloc = yloc.price, style = label.style_label_left, color = #00000000, textcolor = i_cLo, size = txtSize)

    // Retire anything older than the kept window.
    if array.size(line.all) > 0
        while array.size(line.all) > i_hist * 2
            line.delete(array.shift(line.all))
    if array.size(label.all) > 0
        while array.size(label.all) > i_hist * 2
            label.delete(array.shift(label.all))

else if inSess and not na(hiPx)
    if high > hiPx
        hiPx  := high
        hiMs  := time
        hiBar := bar_index
    if low < loPx
        loPx  := low
        loMs  := time
        loBar := bar_index


// ---- draw -------------------------------------------------------------------
// Age is measured to the live clock on the last bar and to the bar's own time
// everywhere else, so replayed history reads exactly as it did at the time.
nowMs = barstate.islast ? timenow : time

if inSess and not na(hiLine)
    hiAge = nowMs - hiMs
    loAge = nowMs - loMs
    hiR   = f_ramp(hiAge)
    loR   = f_ramp(loAge)

    line.set_xy1(hiLine, hiBar, hiPx)
    line.set_xy2(hiLine, bar_index, hiPx)
    line.set_color(hiLine, color.new(i_cHi, int(i_fade * (1 - hiR))))
    line.set_width(hiLine, int(math.round(i_wmin + (i_wmax - i_wmin) * hiR)))

    line.set_xy1(loLine, loBar, loPx)
    line.set_xy2(loLine, bar_index, loPx)
    line.set_color(loLine, color.new(i_cLo, int(i_fade * (1 - loR))))
    line.set_width(loLine, int(math.round(i_wmin + (i_wmax - i_wmin) * loR)))

    if i_lbl and not na(hiLab)
        label.set_xy(hiLab, bar_index, hiPx)
        label.set_text(hiLab, "  " + f_dur(hiAge))
        label.set_textcolor(hiLab, color.new(i_cHi, int(i_fade * (1 - hiR))))
        label.set_xy(loLab, bar_index, loPx)
        label.set_text(loLab, "  " + f_dur(loAge))
        label.set_textcolor(loLab, color.new(i_cLo, int(i_fade * (1 - loR))))


// ---- corner readout ---------------------------------------------------------
tPos = switch i_pos
    "Top right"    => position.top_right
    "Top left"     => position.top_left
    "Bottom right" => position.bottom_right
    =>                position.bottom_left

var table t = na
if i_table and barstate.islast
    if na(t)
        t := table.new(tPos, 2, 3, border_width = 1)
    hiAge = nowMs - hiMs
    loAge = nowMs - loMs

    table.cell(t, 0, 0, "STOOD", text_color = color.new(color.gray, 0), text_size = txtSize, text_halign = text.align_left)
    table.cell(t, 1, 0, "", text_size = txtSize)

    table.cell(t, 0, 1, "high", text_color = i_cHi, text_size = txtSize, text_halign = text.align_left)
    table.cell(t, 1, 1, inSess ? f_dur(hiAge) : "--", text_color = i_cHi, text_size = txtSize, text_halign = text.align_right)

    table.cell(t, 0, 2, "low", text_color = i_cLo, text_size = txtSize, text_halign = text.align_left)
    table.cell(t, 1, 2, inSess ? f_dur(loAge) : "--", text_color = i_cLo, text_size = txtSize, text_halign = text.align_right)


// ---- plots for alerts / data window -----------------------------------------
// Exposed as minutes so an alert or another study can read the clock directly.
plot(inSess ? (nowMs - hiMs) / 60000.0 : na, "High stood (min)", display = display.data_window)
plot(inSess ? (nowMs - loMs) / 60000.0 : na, "Low stood (min)",  display = display.data_window)
plot(inSess ? hiPx : na, "Session high", display = display.data_window)
plot(inSess ? loPx : na, "Session low",  display = display.data_window)