Andra Algo

//version=5
indicator(title="Andra Algo V 1.2", shorttitle="Andra Algo V1.2", overlay=true)

// =====================
// INPUT
// =====================
src = input(defval=close, title="Source")
per = input.int(defval=100, minval=1, title="Sampling Period")
mult = input.float(defval=3.0, minval=0.1, title="Range Multiplier")

// =====================
// COLOR SET
// =====================
buyLineColor = color.white
sellLineColor = color.blue
midColor = #90bff9

buyBgColor = color.new(color.gray, 20)
sellBgColor = color.new(color.blue, 20)

// =====================
// SMOOTH RANGE
// =====================
smoothrng(x, t, m) =>
wper = t * 2 - 1
avrng = ta.ema(math.abs(x - x[1]), t)
ta.ema(avrng, wper) * m

smrng = smoothrng(src, per, mult)

// =====================
// RANGE FILTER
// =====================
rngfilt(x, r) =>
rf = x
rf := x > nz(rf[1]) ?
(x - r < nz(rf[1]) ? nz(rf[1]) : x - r) :
(x + r > nz(rf[1]) ? nz(rf[1]) : x + r)
rf

filt = rngfilt(src, smrng)

// =====================
// TREND DIRECTION
// =====================
upward = 0.0
upward := filt > filt[1] ? nz(upward[1]) + 1 : filt < filt[1] ? 0 : nz(upward[1])

downward = 0.0
downward := filt < filt[1] ? nz(downward[1]) + 1 : filt > filt[1] ? 0 : nz(downward[1])

// =====================
// MID LINE COLOR
// =====================
filtColor = upward > 0 ? buyLineColor : downward > 0 ? sellLineColor : midColor
plot(filt, title="Mid Line", color=filtColor, linewidth=2)

// =====================
// BUY & SELL CONDITIONS
// =====================
longCond = src > filt and upward > 0
shortCond = src < filt and downward > 0

CondIni = 0
CondIni := longCond ? 1 : shortCond ? -1 : CondIni[1]

longCondition = longCond and CondIni[1] == -1
shortCondition = shortCond and CondIni[1] == 1

// =====================
// SIGNALS (FIXED BG COLOR)
// =====================
plotshape(longCondition, title="Buy Signal", text="BUY", style=shape.labelup, location=location.belowbar, size=size.small, textcolor=color.white, color=buyBgColor)
plotshape(shortCondition, title="Sell Signal", text="SELL", style=shape.labeldown, location=location.abovebar, size=size.small, textcolor=color.white, color=sellBgColor)

// =====================
// ALERTS
// =====================
alertcondition(longCondition, title="Buy Alert", message="Andra Algo V1.2 BUY")
alertcondition(shortCondition, title="Sell Alert", message="Andra Algo V1.2 SELL")