/**
 * Waterfall-layout math: trace time envelope, per-span bar geometry, a
 * human-friendly time axis, overlapping-span row packing, and ∑-cost
 * aggregation. Every function is pure and total — it NEVER throws and NEVER
 * does I/O — so skew / missing-timestamp / overlap / degenerate-bounds
 * negative cases are provable without rendering.
 */
import type { TraceSpan } from "./types.js";
/**
 * Trace time bounds — min start / max end across ALL spans (ns, bigint-safe):
 * the honest envelope for the waterfall denominator (not root-only, which
 * would let a child overflow). Unparseable timestamps are skipped; a trace
 * with no timestamps returns 0/0.
 */
export declare function computeTraceBounds(root: TraceSpan): {
    startNs: bigint;
    endNs: bigint;
};
export interface BarLayout {
    leftPct: number;
    widthPct: number;
    unbounded: boolean;
}
/**
 * Map a span's [start, end] against the trace bounds → clamped {leftPct,
 * widthPct} in [0,100] with `leftPct + widthPct ≤ 100`. Missing end and
 * clock-skew (end < start) are flagged `unbounded` with zero width — never a
 * throw. Percentages carry 2 decimals via integer bigint math.
 */
export declare function computeBarLayout(spanStart: bigint | string | undefined, spanEnd: bigint | string | null | undefined, traceStartNs: bigint, traceEndNs: bigint): BarLayout;
/** One tick on the waterfall time axis. */
export interface AxisTick {
    offsetNs: bigint;
    label: string;
    leftPct: number;
}
/**
 * Human-friendly time axis: pick a step from the 1/2/5×10ⁿ ladder so ticks
 * sit ≥70px apart, then emit ticks at 0, step, 2·step, … across the span.
 * Total: a degenerate window or non-positive width yields an empty axis.
 */
export declare function niceAxisTicks(startNs: bigint, endNs: bigint, pxWidth: number): AxisTick[];
/**
 * Greedy single-pass row packing for overlapping spans: sort by start, then
 * assign each span the lowest row whose last-placed span ended at/before this
 * span's start. Returns `Map<id, rowIndex>`. Total: `[]` → empty map.
 */
export declare function packRows(spans: Array<{
    id: string;
    startNs: bigint;
    endNs: bigint;
}>): Map<string, number>;