Center Of Gravity Oscillator

// This source code is subject to the terms of the Mozilla Public License 2.0 at https://mozilla.org/MPL/2.0/
// © veryfid — enhanced by claygrace74

//@version=6
indicator("Center Of Gravity Oscillator", shorttitle="COG", precision=4)

// ==================== COG Settings ====================
var cog_group = "COG Settings"
src     = input.source(close, "Source", group=cog_group)
length  = input.int(9, "COG Length", minval=1, group=cog_group)
smooth  = input.string("NONE", "Smoothing", options=["RMA", "NONE"], group=cog_group)
length5 = input.int(2, "Smoothing Length", minval=1, group=cog_group)

// ==================== Trigger Settings ====================
var trig_group = "Trigger Settings"
windowsize = input.int(3, "Window Size", group=trig_group)
trigOffset = input.float(0.85, "Offset", group=trig_group)
sigma      = input.float(6.0, "Sigma", group=trig_group)

// ==================== Theme & Display ====================
var theme_group = "Theme & Display"
theme   = input.string("CUSTOM", "Theme", options=["CUSTOM", "CLEAN", "FIBONACCI", "FIBONACCI 2"], group=theme_group)
pline   = input.bool(true, "Show Price Line", group=theme_group)
showcol = input.bool(false, "Dual Colored Trigger", group=theme_group)
showhl  = input.bool(false, "Show High/Low Levels", group=theme_group)

// ==================== LSMA & Range ====================
var lsma_group = "LSMA & Range"
length2 = input.int(20, "Previous High/Low Length", minval=1, group=lsma_group)
length3 = input.int(200, "LSMA Length", minval=1, group=lsma_group)

// ==================== Fibonacci Settings ====================
var fib_group = "Fibonacci Settings"
fib     = input.bool(false, "Show Fibonacci Levels", group=fib_group)
length4 = input.int(1000, "Fibonacci Lookback", minval=1, group=fib_group)
col1    = input.color(color.white, "Fibonacci Color", group=fib_group)

// ==================== Signal Settings ====================
var sig_group = "Signal Settings"
i_showSignals    = input.bool(true, "Show Buy/Sell Signals", group=sig_group)
i_showDivergence = input.bool(false, "Show Divergence Signals", group=sig_group)
i_divLookback    = input.int(5, "Divergence Lookback", minval=3, group=sig_group)

// ==================================================================================
// Theme Logic
// ==================================================================================
bool useFib    = fib
int  fibLen    = length4
bool useDualCol = showcol

if theme == "FIBONACCI"
    useFib  := true
    fibLen  := 50
if theme == "FIBONACCI 2"
    useFib    := true
    fibLen    := 30
    useDualCol := true

// ==================================================================================
// Core Calculations
// ==================================================================================
COG1   = ta.cog(src, length)
cogRma = ta.rma(COG1, length5)

COG = smooth == "RMA" ? cogRma : COG1
if theme == "CLEAN"
    COG := ta.rma(COG1, 9)

trigger = ta.alma(COG, windowsize, trigOffset, sigma)
lsma    = ta.linreg(COG, length3, 0)

// Momentum coloring — acceleration based
cogChange = ta.change(COG)
cogAccel  = ta.change(cogChange)
cogColor  = cogAccel > 0 ? (cogChange > 0 ? color.green : color.new(color.orange, 30)) : (cogChange > 0 ? color.new(color.green, 50) : color.red)

// Previous high/low
cogHigh = ta.highest(COG, length2)
cogLow  = ta.lowest(COG, length2)

// Fibonacci levels
h = ta.highest(COG, fibLen)
l = ta.lowest(COG, fibLen)
cogRange = h - l

l1 = h - cogRange * 0.236
l2 = h - cogRange * 0.382
l3 = h - cogRange * 0.618
l4 = h - cogRange * 0.764
l5 = h - cogRange * 0.5

// ==================================================================================
// Signals
// ==================================================================================
enter = ta.crossover(COG, trigger)
exit  = ta.crossunder(COG, trigger)

// Divergence detection (simplified)
priceHigh    = high > ta.highest(high, i_divLookback)[1]
cogNotHigh   = COG < ta.highest(COG, i_divLookback)[1]
bearDiv      = priceHigh and cogNotHigh

priceLow     = low < ta.lowest(low, i_divLookback)[1]
cogNotLow    = COG > ta.lowest(COG, i_divLookback)[1]
bullDiv      = priceLow and cogNotLow

// ==================================================================================
// Plots
// ==================================================================================

// Reference line
plot(-5, color=color.new(color.black, 50), style=plot.style_line, linewidth=1, title="Reference")

// Previous high/low (hidden for fib themes)
isFibTheme = theme == "FIBONACCI" or theme == "FIBONACCI 2"
p1 = plot(not isFibTheme ? cogLow : na,  color=color.new(color.green, 100), title="Previous Low")
p2 = plot(not isFibTheme ? cogHigh : na, color=color.new(color.red, 100),   title="Previous High")

// COG price line (momentum colored)
c2 = plot(pline ? COG : na, color=cogChange > 0 ? color.new(#00ffaa, 0) : color.new(color.red, 0), linewidth=theme == "FIBONACCI 2" ? 3 : 1, title="COG Trend Line", trackprice=true)

// COG main line
c = plot(theme != "FIBONACCI 2" and theme != "CLEAN" ? COG : na, color=cogColor, linewidth=2, title="COG")

// Fills for previous high/low
fill(p1, c, title="Previous Low Fill")
fill(p2, c, color=color.new(color.red, 80), title="Previous High Fill")

// Trigger line
trigColor = useDualCol ? (cogChange > 0 ? color.green : color.red) : color.blue
plot(not isFibTheme and theme != "CLEAN" ? trigger : na, title="Trigger", color=trigColor)

// LSMA
plot(not isFibTheme ? lsma : na, color=color.red, title="LSMA")

// Clean theme specific
plot(theme == "CLEAN" ? COG : na,          color=color.blue,  linewidth=3, title="COG Clean")
plot(theme == "CLEAN" ? ta.sma(COG, 2) : na, color=color.white, linewidth=2, title="COG Clean SMA")

// Fibonacci levels
f1 = plot(useFib ? l1 : na, color=color.new(col1, 60), title="0.236")
f2 = plot(useFib ? l2 : na, color=color.new(col1, 60), title="0.382")
f3 = plot(useFib ? l3 : na, color=color.new(col1, 60), title="0.618")
f4 = plot(useFib ? l4 : na, color=color.new(col1, 60), title="0.764")
f5 = plot(useFib ? l5 : na, color=theme == "FIBONACCI 2" ? color.new(#ffe0b2, 20) : color.new(col1, 60), title="0.5")

// High/low boundary lines
p3 = plot(showhl or theme == "FIBONACCI" ? h : na, title="High")
p4 = plot(showhl or theme == "FIBONACCI" ? l : na, title="Low")
p5 = plot(theme == "FIBONACCI 2" ? h : na, title="High F2", color=color.red)
p6 = plot(theme == "FIBONACCI 2" ? l : na, title="Low F2",  color=color.green)

// Fibonacci 2 fills
fill(p5, f1, color=color.new(color.red, 80))
fill(p5, f2, color=color.new(color.red, 80))
fill(p6, f4, color=color.new(color.green, 80))
fill(p6, f3, color=color.new(color.green, 80))

// ==================================================================================
// Signal Shapes
// ==================================================================================
plotshape(i_showSignals and enter, style=shape.triangleup,   location=location.bottom, color=color.green, text="Buy",  textcolor=color.green, size=size.tiny, title="Buy Signal")
plotshape(i_showSignals and exit,  style=shape.triangledown, location=location.top,    color=color.red,   text="Sell", textcolor=color.red,   size=size.tiny, title="Sell Signal")

// Divergence background highlights
bgcolor(i_showDivergence and bearDiv ? color.new(color.orange, 85) : na, title="Bearish Divergence")
bgcolor(i_showDivergence and bullDiv ? color.new(color.teal, 85)   : na, title="Bullish Divergence")

// ==================================================================================
// Alert Conditions
// ==================================================================================
alertcondition(enter,    "COG Buy Signal",        "COG crossed above trigger line")
alertcondition(exit,     "COG Sell Signal",        "COG crossed below trigger line")
alertcondition(bullDiv,  "Bullish Divergence",     "Price making new low but COG is not — potential reversal")
alertcondition(bearDiv,  "Bearish Divergence",     "Price making new high but COG is not — potential reversal")