Capital41 ADX Filter

// Copyright (c) 2026 Capital41 | MIT License
// CAPITAL41 ADX FILTER v3

// What it does:
// - Shows ADX trend strength with DI+ and DI- directional indicators.
// - Background highlight when trend strength exceeds threshold.
// - DI crossover detection for trend direction changes.
// - Status badge and comprehensive alerts.
//
// v2 changes (expanded from 34-line original):
// - ADDED: DI+ and DI- lines with directional fill.
// - ADDED: ADX color changes by trend direction (DI+ > DI- = bull, DI- > DI+ = bear).
// - ADDED: Strong trend threshold zone.
// - ADDED: Status badge showing ADX value, DI+/DI-, and direction.
// - ADDED: Alert conditions (ADX threshold crosses, DI crossovers, strong trend).
//
// v3 changes:
// - FIXED: DI crossovers and ADX threshold crosses gated by barstate.isconfirmed,
//          so alerts fire on bar close instead of flickering intra-bar.
//
// TradingView setup:
// 1) Open TradingView -> Pine Editor.
// 2) Paste this script, Save, and Add to chart.
// 3) Use 30m or 4h on BTC or US stocks.
//
// Usage guide (30m/4h):
// - Only take trades when ADX is above threshold (default 20).
// - DI+ > DI- = bullish trend direction; DI- > DI+ = bearish.
// - DI crossovers signal potential trend direction changes.
// - Strong trend zone (35+) indicates powerful trending conditions.
// - Combine with Fusion Scalp, Confluence, or Regime Matrix signals.



//@version=6
indicator("Capital41 ADX Filter v3", overlay = false, max_labels_count = 50)

// Inputs
adxLen       = input.int(14, "DI length", minval = 2)
adxSmooth    = input.int(14, "ADX smoothing", minval = 1)
threshold    = input.int(20, "Trend threshold", minval = 5, maxval = 50)
strongThresh = input.int(35, "Strong trend threshold", minval = 20, maxval = 60)

showDI       = input.bool(true, "Show DI+/DI- lines")
showFill     = input.bool(true, "Show DI fill")
showBg       = input.bool(true, "Highlight trending")
showBadge    = input.bool(true, "Show status badge")

colorBull    = color.new(color.lime, 0)
colorBear    = color.new(color.red, 0)
colorNeutral = color.new(color.gray, 80)

// Compute DI+, DI-, and ADX via ta.dmi
[diPlus, diMinus, adxVal] = ta.dmi(adxLen, adxSmooth)

// Trend direction
bullDir     = diPlus > diMinus
bearDir     = diMinus > diPlus

// Trend strength classification
trending    = adxVal >= threshold
strongTrend = adxVal >= strongThresh

// ADX color based on direction and strength
adxColor = not trending ? color.new(color.gray, 0) : bullDir ? colorBull : colorBear

// Plots
plot(adxVal, title = "ADX", color = adxColor, linewidth = 2)
diPlusPlot  = plot(showDI ? diPlus : na,  title = "DI+", color = color.new(colorBull, 30), linewidth = 1)
diMinusPlot = plot(showDI ? diMinus : na, title = "DI-", color = color.new(colorBear, 30), linewidth = 1)

plot(threshold,    title = "Threshold", color = color.new(color.gray, 60), style = plot.style_line)
plot(strongThresh, title = "Strong",    color = color.new(color.orange, 60), style = plot.style_line)

// Fill between DI lines
fill(diPlusPlot, diMinusPlot,
     color = showFill and showDI ? (bullDir ? color.new(colorBull, 88) : color.new(colorBear, 88)) : na)

// Background
color bgColor = na
if showBg and strongTrend
    bgColor := bullDir ? color.new(colorBull, 85) : color.new(colorBear, 85)
else if showBg and trending
    bgColor := color.new(color.green, 92)
bgcolor(bgColor)

// DI crossovers and ADX threshold crosses (confirmed: lines can cross and
// uncross several times within one bar)
diCrossUp    = ta.crossover(diPlus, diMinus)   and barstate.isconfirmed
diCrossDown  = ta.crossunder(diPlus, diMinus)  and barstate.isconfirmed

adxCrossUp   = ta.crossover(adxVal, threshold)    and barstate.isconfirmed
adxCrossDown = ta.crossunder(adxVal, threshold)   and barstate.isconfirmed
adxCrossHigh = ta.crossover(adxVal, strongThresh) and barstate.isconfirmed

// Status badge
var table status = table.new(position.bottom_left, 4, 1, border_width = 1)
if barstate.islast
    if showBadge
        adxText = " ADX " + str.tostring(adxVal, "#.0") + " "
        diPText = " DI+ " + str.tostring(diPlus, "#.0") + " "
        diMText = " DI- " + str.tostring(diMinus, "#.0") + " "
        dirText = bullDir ? " BULL " : bearDir ? " BEAR " : " FLAT "

        adxBg = strongTrend ? color.new(color.orange, 60) : trending ? color.new(color.green, 70) : colorNeutral
        table.cell(status, 0, 0, adxText, bgcolor = adxBg, text_color = color.white, text_size = size.tiny)
        table.cell(status, 1, 0, diPText, bgcolor = color.new(colorBull, 70), text_color = color.white, text_size = size.tiny)
        table.cell(status, 2, 0, diMText, bgcolor = color.new(colorBear, 70), text_color = color.white, text_size = size.tiny)
        table.cell(status, 3, 0, dirText, bgcolor = bullDir ? color.new(colorBull, 65) : bearDir ? color.new(colorBear, 65) : colorNeutral, text_color = color.white, text_size = size.tiny)
    else
        for i = 0 to 3
            table.cell(status, i, 0, "", bgcolor = color.new(color.black, 100), text_color = color.new(color.black, 100))

// Alerts
alertcondition(adxCrossUp, title = "ADX Above Threshold",
               message = "ADX Filter: ADX crossed above threshold on {{ticker}} ({{interval}})")

alertcondition(adxCrossDown, title = "ADX Below Threshold",
               message = "ADX Filter: ADX crossed below threshold on {{ticker}} ({{interval}})")

alertcondition(diCrossUp, title = "DI+ Crossover",
               message = "ADX Filter: DI+ crossed above DI- (bullish) on {{ticker}} ({{interval}})")

alertcondition(diCrossDown, title = "DI- Crossover",
               message = "ADX Filter: DI- crossed above DI+ (bearish) on {{ticker}} ({{interval}})")

alertcondition(adxCrossHigh, title = "Strong Trend",
               message = "ADX Filter: ADX crossed into strong trend zone on {{ticker}} ({{interval}})")