Pine Script: Using a plotted value in an if statement

Question

I'm new to structural programming languages and I'm trying to make an indicator and a strategy based on 2 stochastic oscillators, one being faster than the other. Crossover/under value of the 2 oscillators and the values of the slower and the faster oscillator are used to determine the entry and exit conditions. Here are the conditions described in Structured English:

IF crossover is below 25 OR slow stoch oscil is below 20 THEN
   Open long position
ELSE
   IF fast stoch oscil is above 90 THEN
      Close long position
   ELSE
      Do nothing
   ENDIF
ENDIF
IF crossunder is above 75 OR slow stoch oscil is above 80 THEN
   Open short position
ELSE
   IF fast stoch oscil is below 10 THEN
      Close short position
   ELSE
      Do nothing
   ENDIF
ENDIF
EXIT

and in pseudocode:

crossover = (stoch_slow, stoch_fast)
crossunder = (stoch_slow, stoch_fast)
long
  if crossover < 25 or stoch_slow < 20
    close_long
      if long == true and stoch_fast > 90
short
  if crossunder > 75 or stoch_slow > 80
    close_short
     if short == true and stoch_fast < 10

I read the relevant sections of the Pine Script's User Manual, but couldn't finding a similar example, and, in the end, only managed to plot all of the instances of an crossover/under.

//@version=5
indicator(title="Stochastic oscillator-SlowFast", shorttitle="Stoch-SF", overlay=false)
// Input and calculate values
periodKs = input.int(10)
smoothKs = input.int(10)
ks = ta.sma(ta.stoch(close, high, low, periodKs), smoothKs)
periodKf = input.int(6)
smoothKf = input.int(3)
kf = ta.sma(ta.stoch(close, high, low, periodKf), smoothKf)
// Plot crossover/under circles
long = plot(ta.crossover(ks, kf) ? kf : na, color=color.teal, linewidth=3, style=plot.style_circles)
short = plot(ta.crossunder(ks, kf) ? kf : na, color=color.red, linewidth=3, style=plot.style_circles)
// Plot Stochastics lines
plot(ks, color=color.yellow)
plot(kf, color=color.white)
hline(18)
hline(36)
hline(64)
hline(82)

Later, I've found another way to accomplish the marking of crossovers/unders on TradingCode.net, replacing the "// Plot crossover/under circles" section in the above code:

co = ta.crossover(ks, kf)
cu = ta.crossunder(ks, kf)
// Colour the background when a crossover/under happens
backgroundColour = if co
    color.new(color.teal, 80)
else if cu
    color.new(color.orange, 80)
bgcolor(backgroundColour)

but I haven't found a way to assimilate the boolean and floating point values to 1 common type.

TLDR How to get a value of a crossover/under and plot only those who are over/under a certain fixed value.

Answer 1

It was fun figuring out the solution and I even figured out a solution to a secondary problem, which I didn't mention. The next code replaces the last code block of my question:

sfco = ta.crossover(kf, ks) and kf < 25 or ks < 20 //Open long position
sfcu = ta.crossunder(kf, ks) and kf > 75 or ks > 80 //Open short position
// Color the background when long conditions are met
opencolor = if sfco
    color.new(color.teal, 80)
else if sfcu
    color.new(color.orange, 80)
bgcolor(opencolor)