ZigZag reSampled

// This source code is subject to the terms of the Mozilla Public License 2.0 at https://mozilla.org/MPL/2.0/
// © dy6m1

//@version=4
study("ZigZag reSampled", overlay = true)

depth = input(15 , title = "Depth")
length = input(7, title = "Backsteps")

var bool upward = true
var float lastlow = low
var float lasthigh = high
var int timelow = 1
var int timehigh = 1
var line trendline = na

h = highest(high , depth)
l = lowest(low , depth)


if (upward)
    if (low[length] < lastlow) and (l == low[length])
        lastlow := low[length]
        timelow := bar_index
        //delete line
        line.delete(trendline)
        //draw new line
        trendline := line.new(timehigh - length , lasthigh , timelow - length, lastlow , xloc.bar_index, color = color.purple , width = 2)
        
    if (high[length] > lastlow) and (h == high[length])
        lasthigh := high[length]
        timehigh := bar_index
        upward := false
        //draw line
        trendline := line.new(timehigh - length , lasthigh , timelow - length, lastlow , xloc.bar_index , color = color.purple , width = 2)

if (not upward)
    if (high[length] > lasthigh) and (h == high[length])
        lasthigh := high[length]
        timehigh := bar_index
        //delete line
        line.delete(trendline)
        //draw new line
        trendline := line.new(timehigh - length , lasthigh , timelow - length, lastlow , xloc.bar_index, color = color.purple , width = 2)
        
    if (low[length] < lasthigh) and (l == low[length])
        lastlow := low[length]
        timelow := bar_index
        upward := true
        //draw new line
        trendline := line.new(timehigh - length , lasthigh , timelow - length, lastlow , xloc.bar_index, color = color.purple , width = 2)


// plot(upward ? 1.0 : 0.0 , color = color.blue)
// plot(h , color = color.green)
// plot(l , color = color.red)