STD/Clutter-Filtered, Variety FIR Filters [Loxx]
// This source code is subject to the terms of the Mozilla Public License 2.0 at https://mozilla.org/MPL/2.0/
// © loxx

//@version=5
indicator("STD/Clutter-Filtered, Variety FIR Filters [Loxx]",
     shorttitle = "STDCFVFIRF [Loxx]",
     overlay = true, 
     timeframe="", 
     timeframe_gaps = true)

import loxx/loxxexpandedsourcetypes/4

greencolor = #2DD204
redcolor = #D2042D 

fir_rect = "Rectangular - simple moving average"
fir_hann = "Hanning"
fir_hamm = "Hamming"
fir_blck = "Blackman"
fir_blha = "Blackman/Harris"
fir_lwma = "Linear weighted"
fir_tma  = "Triangular"

design(int per, string type)=>
    float[] coeffs = array.new<float>(per, 0)
    float coeffsSum = 0
    float _div = per + 1.0
    float _coeff = 1
    for i = 0 to per - 1 
        switch type 
            fir_rect =>
                _coeff := 1.0
            fir_hann =>
                _coeff := 0.50 - 0.50 * math.cos(2.0 * math.pi * (i + 1) / _div)
            fir_hamm =>
                _coeff := 0.54 - 0.46 * math.cos(2.0 * math.pi * (i + 1) / _div)
            fir_blck =>
                _coeff := 0.42 - 0.50 * math.cos(2.0 * math.pi * (i + 1) / _div) + 0.08 * math.cos(4.0 * math.pi * i / _div)
            fir_blha =>
                _coeff := 0.35875 - 0.48829 * math.cos(2.0 * math.pi * (i + 1) / _div) + 0.14128 * math.cos(4.0 * math.pi * (i + 1) / _div) - 0.01168 * math.cos(6.0 * math.pi * (i + 1) / _div)
            fir_lwma =>
                _coeff := per - i
            fir_tma =>
                _coeff := i + 1.0
                if (_coeff > ((per + 1.0) / 2.0)) 
                    _coeff := per - i
        array.set(coeffs,i, _coeff)
        coeffsSum += _coeff
    [coeffs, coeffsSum]

clutterFilt(float src, float threshold)=>
    bool out = math.abs(ta.roc(src, 1)) > threshold
    out
    
stdFilter(float src, int len, float filter)=>
    float price = src
    float filtdev = filter * ta.stdev(src, len)
    price := math.abs(price - nz(price[1])) < filtdev ? nz(price[1]) : price
    price
    
smthtype = input.string("Kaufman", "Heiken-Ashi Better Smoothing", options = ["AMA", "T3", "Kaufman"], group=  "Source Settings")
srcoption = input.string("HAB Median", "Source", group= "Source Settings", 
     options = 
     ["Close", "Open", "High", "Low", "Median", "Typical", "Weighted", "Average", "Average Median Body", "Trend Biased", "Trend Biased (Extreme)", 
     "HA Close", "HA Open", "HA High", "HA Low", "HA Median", "HA Typical", "HA Weighted", "HA Average", "HA Average Median Body", "HA Trend Biased", "HA Trend Biased (Extreme)",
     "HAB Close", "HAB Open", "HAB High", "HAB Low", "HAB Median", "HAB Typical", "HAB Weighted", "HAB Average", "HAB Average Median Body", "HAB Trend Biased", "HAB Trend Biased (Extreme)"])

per = input.int(14, "Period", group = "Basic Settings")
type = input.string(fir_lwma, "FIR Digital Filter Type", options = [fir_rect, fir_hann, fir_hamm, fir_blck, fir_blha, fir_lwma, fir_tma], group = "Basic Settings")
sth = input.float(0.15, "Clutter Filter Threshold", group = "Basic Settings", step = 0.001)

colorbars = input.bool(true, "Color bars?", group = "UI Options")
showSigs = input.bool(true, "Show signals?", group= "UI Options")
showdeadzones = input.bool(false, "Show dead zones?", group= "UI Options")

filterop = input.string("Both", "Filter Options", options = ["Price", "STDCFVFIRF", "Both", "None"], group=  "Filter Settings")
filter = input.float(1, "Filter Devaitions", minval = 0, group= "Filter Settings")
filterperiod = input.int(15, "Filter Period", minval = 0, group= "Filter Settings")

kfl=input.float(0.666, title="* Kaufman's Adaptive MA (KAMA) Only - Fast End", group = "Moving Average Inputs")
ksl=input.float(0.0645, title="* Kaufman's Adaptive MA (KAMA) Only - Slow End", group = "Moving Average Inputs")
amafl = input.int(2, title="* Adaptive Moving Average (AMA) Only - Fast", group = "Moving Average Inputs")
amasl = input.int(30, title="* Adaptive Moving Average (AMA) Only - Slow", group = "Moving Average Inputs")

haclose = request.security(ticker.heikinashi(syminfo.tickerid), timeframe.period, close)
haopen = request.security(ticker.heikinashi(syminfo.tickerid), timeframe.period, open)
hahigh = request.security(ticker.heikinashi(syminfo.tickerid), timeframe.period, high)
halow = request.security(ticker.heikinashi(syminfo.tickerid), timeframe.period, low)
hamedian = request.security(ticker.heikinashi(syminfo.tickerid), timeframe.period, hl2)
hatypical = request.security(ticker.heikinashi(syminfo.tickerid), timeframe.period, hlc3)
haweighted = request.security(ticker.heikinashi(syminfo.tickerid), timeframe.period, hlcc4)
haaverage = request.security(ticker.heikinashi(syminfo.tickerid), timeframe.period, ohlc4)

float src = switch srcoption
	"Close" => loxxexpandedsourcetypes.rclose()
	"Open" => loxxexpandedsourcetypes.ropen()
	"High" => loxxexpandedsourcetypes.rhigh()
	"Low" => loxxexpandedsourcetypes.rlow()
	"Median" => loxxexpandedsourcetypes.rmedian()
	"Typical" => loxxexpandedsourcetypes.rtypical()
	"Weighted" => loxxexpandedsourcetypes.rweighted()
	"Average" => loxxexpandedsourcetypes.raverage()
    "Average Median Body" => loxxexpandedsourcetypes.ravemedbody()
	"Trend Biased" => loxxexpandedsourcetypes.rtrendb()
	"Trend Biased (Extreme)" => loxxexpandedsourcetypes.rtrendbext()
	"HA Close" => loxxexpandedsourcetypes.haclose(haclose)
	"HA Open" => loxxexpandedsourcetypes.haopen(haopen)
	"HA High" => loxxexpandedsourcetypes.hahigh(hahigh)
	"HA Low" => loxxexpandedsourcetypes.halow(halow)
	"HA Median" => loxxexpandedsourcetypes.hamedian(hamedian)
	"HA Typical" => loxxexpandedsourcetypes.hatypical(hatypical)
	"HA Weighted" => loxxexpandedsourcetypes.haweighted(haweighted)
	"HA Average" => loxxexpandedsourcetypes.haaverage(haaverage)
    "HA Average Median Body" => loxxexpandedsourcetypes.haavemedbody(haclose, haopen)
	"HA Trend Biased" => loxxexpandedsourcetypes.hatrendb(haclose, haopen, hahigh, halow)
	"HA Trend Biased (Extreme)" => loxxexpandedsourcetypes.hatrendbext(haclose, haopen, hahigh, halow)
	"HAB Close" => loxxexpandedsourcetypes.habclose(smthtype, amafl, amasl, kfl, ksl)
	"HAB Open" => loxxexpandedsourcetypes.habopen(smthtype, amafl, amasl, kfl, ksl)
	"HAB High" => loxxexpandedsourcetypes.habhigh(smthtype, amafl, amasl, kfl, ksl)
	"HAB Low" => loxxexpandedsourcetypes.hablow(smthtype, amafl, amasl, kfl, ksl)
	"HAB Median" => loxxexpandedsourcetypes.habmedian(smthtype, amafl, amasl, kfl, ksl)
	"HAB Typical" => loxxexpandedsourcetypes.habtypical(smthtype, amafl, amasl, kfl, ksl)
	"HAB Weighted" => loxxexpandedsourcetypes.habweighted(smthtype, amafl, amasl, kfl, ksl)
	"HAB Average" => loxxexpandedsourcetypes.habaverage(smthtype, amafl, amasl, kfl, ksl)
    "HAB Average Median Body" => loxxexpandedsourcetypes.habavemedbody(smthtype, amafl, amasl, kfl, ksl)
	"HAB Trend Biased" => loxxexpandedsourcetypes.habtrendb(smthtype, amafl, amasl, kfl, ksl)
	"HAB Trend Biased (Extreme)" => loxxexpandedsourcetypes.habtrendbext(smthtype, amafl, amasl, kfl, ksl)
	=> haclose

src := filterop == "Both" or filterop == "Price" and filter > 0 ? stdFilter(src, filterperiod, filter) : src

[coeffs, coeffsSum] = design(per, type)

float dSum = 0
for k = 0 to per - 1
    dSum += nz(src[k]) * array.get(coeffs, k)

out = coeffsSum != 0 ? dSum / coeffsSum : 0

out := filterop == "Both" or filterop == "STDCFVFIRF" and filter > 0 ? stdFilter(out, filterperiod, filter) : out
sig = nz(out[1])

filtTrend = clutterFilt(out, sth)
state = filtTrend ? (out > sig ? 1 : out < sig ? -1 : 0) : 0

pregoLong = state == 1
pregoShort =state == -1

contsw = 0
contsw := nz(contsw[1])
contsw := pregoLong ? 1 : pregoShort ? -1 : nz(contsw[1])

goLong = pregoLong and nz(contsw[1]) == -1
goShort = pregoShort and nz(contsw[1]) == 1 

color colorout = na
colorout := filtTrend ? (state == 1 ? greencolor : state == -1 ? redcolor : showdeadzones ? color.gray : colorout[1]) : showdeadzones ? color.gray : colorout[1]

plot(out, "STDCFVFIRF MA", color = colorout, linewidth = 3)

barcolor(colorbars ? colorout : na)

plotshape(showSigs and goLong, title = "Long", color = color.yellow, textcolor = color.yellow, text = "L", style = shape.triangleup, location = location.belowbar, size = size.tiny)
plotshape(showSigs and goShort, title = "Short", color = color.fuchsia, textcolor = color.fuchsia, text = "S", style = shape.triangledown, location = location.abovebar, size = size.tiny)

alertcondition(goLong, title = "Long", message = "STD/Clutter Filtered, One-Sided, N-Sinc-Kernel, EFIR Filt [Loxx]: Long\nSymbol: {{ticker}}\nPrice: {{close}}")
alertcondition(goShort, title = "Short", message = "STD/Clutter Filtered, One-Sided, N-Sinc-Kernel, EFIR Filt [Loxx]: Short\nSymbol: {{ticker}}\nPrice: {{close}}")

