// This Strategy was Created by ©NoobSharks
// if you use it and like it, send us some donation: BinancePay ID: 223731148 - Metamask: 0x82782b3ebD1d6bf7faa18a3943fA6f16EBBF3134
// (yes, I might be naive but I trully Believe you will support us)
// For more information about this indicator check "https://www.youtube.com/c/NoobSharksLutanoMercadoCripto" and give us a hand following us on YouTube
// Check also our website includeing strategies, free indicatores and technical analysis videos: https://www.noobsharks.com

// ATTENTION! REPAINTS!

// THIS INDICATOR IS AN UNION OF TWO INDICATORS FROM ©LuxAlgo: NADARAYA WATSON ENVELOPE AND NADARAYA-WATSON ESTIMATOR
// CREDITS FOR THE BASIS OF THE INDICATOR GO TO ©LuxAlgo, I just made some adjustment so both could run together. A set of alerts were also included

//@version=6

indicator(title = '[NB] Indicator - NADARAYA-WATSON Envelope & Estimator', shorttitle = '[NB]IND.Nadaraya.WATSON.Envelope&Estimator', overlay = true, max_bars_back = 1000, max_lines_count = 500, max_labels_count = 500)
length = input.float(330, 'Window Size', maxval = 330, minval = 0)
h = input.float(8., 'Bandwidth')
mult = input.float(3.)
src = input.source(close, 'Source')

up_col = input.color(color.lime, 'Colors', inline = 'col')
dn_col = input.color(color.red, '', inline = 'col')

//----
n = bar_index
var k = 2
var upper = array.new_line(0)
var lower = array.new_line(0)
var centerline = array.new_line(0)

lset(l, x1, y1, x2, y2, col) =>
    line.set_xy1(l, x1, y1)
    line.set_xy2(l, x2, y2)
    line.set_color(l, col)
    line.set_width(l, 2)

if barstate.isfirst
    for i = 0 to length / k - 1 by 1
        array.push(upper, line.new(na, na, na, na))
        array.push(lower, line.new(na, na, na, na))
        array.push(centerline, line.new(na, na, na, na))
        //----
line up = na
line dn = na
line cnt = na

var line lineTest = na
//----
cross_up = 0.
cross_dn = 0.
reference1 = 0.
reference2 = 0.
reference3 = 0.

mae = 0.
y1 = 0.
y2 = 0.

if barstate.islast
    y = array.new_float(0)

    sum_e = 0.
    for i = 0 to length - 1 by 1
        sum = 0.
        sumw = 0.

        for j = 0 to length - 1 by 1
            w = math.exp(-(math.pow(i - j, 2) / (h * h * 2)))
            sum := sum + src[j] * w
            sumw := sumw + w
            sumw

        y2 := sum / sumw
        sum_e := sum_e + math.abs(src[i] - y2)
        array.push(y, y2)

    mae := sum_e / length * mult

    for i = 1 to length - 1 by 1
        y2 := array.get(y, i)
        y1 := array.get(y, i - 1)

        up := array.get(upper, i / k)
        dn := array.get(lower, i / k)
        cnt := array.get(centerline, i / k)

        lset(up, n - i + 1, y1 + mae, n - i, y2 + mae, up_col)
        lset(dn, n - i + 1, y1 - mae, n - i, y2 - mae, dn_col)
        lset(cnt, n - i + 1, y1, n - i, y2, y2 > y1 ? dn_col : up_col)

        if src[i] > y1 + mae and src[i + 1] < y1 + mae
            label.new(n - i, src[i], '▼', color = #00000000, style = label.style_label_down, textcolor = dn_col, textalign = text.align_center)

        if src[i] < y1 - mae and src[i + 1] > y1 - mae
            label.new(n - i, src[i], '▲', color = #00000000, style = label.style_label_up, textcolor = up_col, textalign = text.align_center)


    cross_up := array.get(y, 0) + mae
    cross_dn := array.get(y, 0) - mae
    reference1 := array.get(y, 0)
    reference2 := array.get(y, 2)
    reference3 := array.get(y, 4)
    reference3

bullSign = ta.crossover(src, cross_dn)
bearSign = ta.crossunder(src, cross_up)

center = (cross_up + cross_dn) / 2

centerSignUp = ta.crossover(src, center)
centerSignDown = ta.crossunder(src, center)

bool isCenterBull = false
if reference1 > math.max(reference2, reference3)
    isCenterBull := true
    isCenterBull
else
    isCenterBull := false
    isCenterBull

// ----- ALERTS RELATED TO CENTER LINE
if centerSignUp and isCenterBull
    alert(syminfo.ticker + ' CrossUP GREEN avg (Open Long or Close short)', alert.freq_once_per_bar_close)
if centerSignUp and not isCenterBull
    alert(syminfo.ticker + ' CrossUP RED avg (Keep Shorting or Open Short)', alert.freq_once_per_bar_close)
if centerSignDown and isCenterBull
    alert(syminfo.ticker + ' CrossDOWN GREEN avg (Keep Longing or Open Long)', alert.freq_once_per_bar_close)
if centerSignDown and not isCenterBull
    alert(syminfo.ticker + ' CrossDOWN RED avg (Open Short or Close Long)', alert.freq_once_per_bar_close)

// ----- ALERTS RELATED ON TOP OR BOTTOM OF THE CHANNELS

if not isCenterBull and bullSign
    alert(syminfo.ticker + ' CrossUP RED channel - avg is RED (TP Short or Keep Shorting)', alert.freq_once_per_bar_close)
if isCenterBull and bullSign
    alert(syminfo.ticker + ' CrossUP RED channel - avg is is GREEN (CloseShort AND OpenLong)', alert.freq_once_per_bar_close)
if isCenterBull and bearSign
    alert(syminfo.ticker + ' CrossDOWN GREEN channel - avg is GREEN (TP Long or Keep Longing)', alert.freq_once_per_bar_close)
if not isCenterBull and bearSign
    alert(syminfo.ticker + ' CrossDOWN GREEN channel - avg is is red (CloseLong AND OpenShort)', alert.freq_once_per_bar_close)

var tbRepaintAlert = table.new(position.top_right, 1, 1, bgcolor = #35202b)
if barstate.isfirst
    table.cell(tbRepaintAlert, 0, 0, 'ATTENTION! REPAINTS! @NOOBSHARKS', text_size = size.small, text_color = #cc2f3c)