Stella's Multi-EMA Crossover

//@version=5
indicator("Stella's Multi-EMA Crossover", shorttitle="MEMA", overlay=true)

// Multi-EMA Crossover Indicator
// Shows trend alignment across multiple timeframes

// EMA Periods
ema1_len = input(9, "EMA 1 (Fast)")
ema2_len = input(21, "EMA 2 (Medium)")
ema3_len = input(55, "EMA 3 (Slow)")
ema4_len = input(200, "EMA 4 (Trend)")

// Calculate EMAs
ema1 = ta.ema(close, ema1_len)
ema2 = ta.ema(close, ema2_len)
ema3 = ta.ema(close, ema3_len)
ema4 = ta.ema(close, ema4_len)

// Trend Alignment
all_bull = ema1 > ema2 and ema2 > ema3 and ema3 > ema4
all_bear = ema1 < ema2 and ema2 < ema3 and ema3 < ema4

// Partial Alignment (3 EMAs)
partial_bull = ema1 > ema2 and ema2 > ema3
partial_bear = ema1 < ema2 and ema2 < ema3

// Crossover signals
cross_up_1_2 = ta.crossover(ema1, ema2)
cross_dn_1_2 = ta.crossunder(ema1, ema2)
cross_up_2_3 = ta.crossover(ema2, ema3)
cross_dn_2_3 = ta.crossunder(ema2, ema3)

// Plot EMAs
plot(ema1, "EMA " + str.tostring(ema1_len), color=color.new(color.yellow, 0), linewidth=2)
plot(ema2, "EMA " + str.tostring(ema2_len), color=color.new(color.orange, 0), linewidth=2)
plot(ema3, "EMA " + str.tostring(ema3_len), color=color.new(color.blue, 0), linewidth=2)
plot(ema4, "EMA " + str.tostring(ema4_len), color=color.new(color.purple, 0), linewidth=3)

// Fill trend area
ema_fill_color = all_bull ? color.new(color.green, 80) : all_bear ? color.new(color.red, 80) : na
fill(plot(ema1, display=display.none), plot(ema4, display=display.none), color=ema_fill_color)

// Signals
plotshape(cross_up_1_2 and ema1 > ema4, "Fast Cross Up", shape.triangleup, location.belowbar, color.green, size=size.tiny)
plotshape(cross_dn_1_2 and ema1 < ema4, "Fast Cross Down", shape.triangledown, location.abovebar, color.red, size=size.tiny)

// Strong signals (3+ EMAs aligned)
plotshape(all_bull and not all_bull[1], "Full Bull Align", shape.labelup, location.belowbar, color.green, text="BUY", textcolor=color.white, size=size.small)
plotshape(all_bear and not all_bear[1], "Full Bear Align", shape.labeldown, location.abovebar, color.red, text="SELL", textcolor=color.white, size=size.small)

// Trend Strength Bar
trend_score = (ema1 > ema2 ? 1 : -1) + (ema2 > ema3 ? 1 : -1) + (ema3 > ema4 ? 1 : -1)
trend_bar_color = trend_score >= 2 ? color.green : trend_score <= -2 ? color.red : color.gray
plotshape(trend_score, "Trend Score", shape.circle, location.bottom, trend_bar_color, size=size.tiny, display=display.data_window)

// Alerts
alertcondition(all_bull and not all_bull[1], "Full Bullish Alignment", "All EMAs aligned bullish")
alertcondition(all_bear and not all_bear[1], "Full Bearish Alignment", "All EMAs aligned bearish")
alertcondition(cross_up_1_2, "Fast Cross Up", "EMA 1 crossed above EMA 2")
alertcondition(cross_dn_1_2, "Fast Cross Down", "EMA 1 crossed below EMA 2")