Zig Zag

// Connect confirmed swing highs and lows without using future data.
indicator("Zig Zag", { overlay: true, maxPolylines: 1, maxLabels: 100 });

const depth = input.int("Pivot depth", 5, { min: 2, max: 50 });
const maxPivots = input.int("Maximum pivots", 40, { min: 4, max: 100 });
const showPrices = input.bool("Show pivot prices", false);
const lineColor = input.color("Line color", "#22d3ee");
const lineWidth = input.int("Line width", 2, { min: 1, max: 4 });

const highs = pivothigh(high, depth, depth);
const lows = pivotlow(low, depth, depth);
const pivots = [];

function acceptPivot(kind, index, price) {
  const candidate = { kind, index, price };
  const previous = pivots[pivots.length - 1];
  if (!previous) {
    pivots.push(candidate);
    return;
  }
  if (previous.kind === kind) {
    const moreExtreme = kind === "high" ? price >= previous.price : price <= previous.price;
    if (moreExtreme) pivots[pivots.length - 1] = candidate;
    return;
  }
  pivots.push(candidate);
}

for (let confirmation = 0; confirmation < close.length; confirmation++) {
  const pivotIndex = confirmation - depth;
  if (pivotIndex < 0) continue;
  if (Number.isFinite(highs[confirmation])) acceptPivot("high", pivotIndex, highs[confirmation]);
  if (Number.isFinite(lows[confirmation])) acceptPivot("low", pivotIndex, lows[confirmation]);
}

const visible = pivots.slice(-maxPivots);
if (visible.length >= 2) {
  const points = visible.map((pivot) => chart.point.from_index(pivot.index, pivot.price));
  polyline.new({ points, xloc: "index", color: lineColor, width: lineWidth });
  if (showPrices) {
    visible.forEach((pivot) => label.new({
      x: pivot.index,
      y: pivot.price,
      xloc: "index",
      text: pivot.price.toFixed(2),
      position: pivot.kind === "high" ? "top" : "bottom",
      color: "#0f172a",
      textColor: lineColor,
      size: "small",
    }));
  }
}