Script lifecycle

// PHASE 1: top-level init
// Runs ONCE when the indicator is first evaluated.
// Declare inputs, register plots, create Series here.

const length = input.int("Length", 14, { min: 1, max: 200 });
const src    = input.source("Source", "close");

plot("MA", null, { color: "#22c55eFF", linewidth: 2 });

// PHASE 2: onBar callback
// Runs ONCE per bar, oldest to newest, then once per realtime tick.

onBar((i) => {
  const value = ta.sma(src, length);
  plot("MA", value);
});

onBar((i) => {
  // i === ctx.i() === ctx.barIndex()
  if (i === 0) {
    console.log("First bar in window");
  }
  if (ctx.isLast()) {
    console.log("Realtime bar");
  }
});

// overlay = true
const length = input.int("Length", 14, { min: 1, max: 200 });
const src    = input.source("Source", "close");

plot("MA", null, { color: "#22c55eFF", linewidth: 2 });

onBar((i) => {
  plot("MA", ta.sma(src, length));
});