Moving Average Extension

// This source code is subject to the terms of the Mozilla Public License 2.0 at https://mozilla.org/MPL/2.0/
// © krosenfeld7

//@version=4
study("Moving Average Extension", overlay = true)

resolution = input(title = "Moving Average Resolution", 
     type  = input.resolution, defval = "D")
length     = input(title = "Moving Average Length",
     type  = input.integer, defval = 140, minval = 1)
source     = input(title = "Moving Average Source",
     type  = input.source, defval = close)
maType     = input(title = "Moving Average Type", 
     type  = input.string, defval = "SMA", options = 
     ["EMA", "HMA", "SMA", "VWMA", "WMA"])

ema  = ema(source,  length)
hma  = hma(source,  length)
vwma = vwma(source, length)
wma  = wma(source,  length)
sma  = sma(source,  length)

emaRes = security(syminfo.tickerid, resolution, 
 ema[barstate.isrealtime ? 1 : 0], barmerge.gaps_off, 
 barmerge.lookahead_off)
hmaRes = security(syminfo.tickerid, resolution, 
 hma[barstate.isrealtime ? 1 : 0], barmerge.gaps_off, 
 barmerge.lookahead_off)
vwmaRes = security(syminfo.tickerid, resolution, 
 vwma[barstate.isrealtime ? 1 : 0], barmerge.gaps_off, 
 barmerge.lookahead_off)
wmaRes = security(syminfo.tickerid, resolution, 
 wma[barstate.isrealtime ? 1 : 0], barmerge.gaps_off, 
 barmerge.lookahead_off)
smaRes = security(syminfo.tickerid, resolution, 
 sma[barstate.isrealtime ? 1 : 0], barmerge.gaps_off, 
 barmerge.lookahead_off)

movingAvgRes = smaRes

if maType == "EMA"
    movingAvgRes := emaRes
else if maType == "HMA"
    movingAvgRes := hmaRes
else if maType == "VWMA"
    movingAvgRes := vwmaRes
else if maType == "WMA"
    movingAvgRes := wmaRes

value = log(source / movingAvgRes)

closePlot = plot(close, color = color.new(color.white, transp = 100))

mAvgPlot = plot(movingAvgRes, color = color.new(value < 0 ? color.red : 
     color.green, transp = 0), linewidth = 3)
plot(value, color = color.new(value < 0 ? color.red : 
     color.green, transp = 100))
fill(mAvgPlot, closePlot, color = color.new(value < 0 ? color.red : 
     color.green, transp = 75))

var line1 = line.new(0,0,0,0)
line.set_x1(line1, bar_index)
line.set_x2(line1, bar_index)
line.set_y1(line1, movingAvgRes)
line.set_y2(line1, close)
line.set_style(line1, line.style_dotted)
line.set_width(line1, 3)
line.set_color(line1, color.white)