import type { GlobalStore } from "./state/globalStore.js";
export declare const REDACTED = "[REDACTED]";
/**
 * One thing a statelog event must not carry. A rule gets a value from the
 * event, before any `toJSON` ran on it, and the object that holds the value.
 * It returns the text to log in the value's place, or undefined to leave the
 * value to the next rule.
 */
export type ScrubRule = (raw: unknown, parent: unknown) => string | undefined;
type Replacer = (this: unknown, key: string, value: unknown) => unknown;
/**
 * Build a `JSON.stringify` replacer that runs each rule in order and logs the
 * first replacement. When no rule fires, `fallback` decides (by default the
 * value is kept).
 *
 * A replacer, not a deep copy, so the rules run inside the one stringify that
 * serializes the event, and Date, URL, and other `toJSON` values serialize as
 * they normally would. JSON.stringify applies `toJSON` before it calls the
 * replacer, so `value` may already be converted. `this[key]` still holds the
 * original, and that is what the rules see, since a redact tag is set on the
 * original. At the root key "", `this[""]` is `value`.
 *
 * Cycles are left to JSON.stringify, which throws on them: a cyclic body could
 * never have been serialized in the first place.
 */
export declare function makeScrubReplacer(rules: readonly ScrubRule[], fallback?: Replacer): Replacer;
/**
 * Swap a value marked `redact` for its marker, and scrub a redacted string
 * that was interpolated into a larger one, since that larger string is a new
 * value with no tag of its own. When `globals` holds no tags at all, the rule
 * never fires and costs nothing per value.
 */
export declare function redactRule(globals: GlobalStore): ScrubRule;
/** A string this long or shorter is logged as it is, even when it is base64. */
export declare const BINARY_OMIT_MIN_LENGTH = 4096;
/**
 * Replace picture bytes, and any other binary data sent as base64, with a
 * marker such as `[image/png: 6000 bytes omitted]`. A string matches when it
 * is longer than `BINARY_OMIT_MIN_LENGTH` and is either a `data:` URI with
 * `;base64,`, or all base64 or base64url characters with both upper- and
 * lowercase letters among them. Prose and JSON never match, since they contain
 * spaces or punctuation outside that alphabet. Hex, long numbers, and
 * one-letter filler never match either: base64 of real binary data always
 * mixes the two cases.
 *
 * The mime type comes from the `data:` URI's header, or else from a string
 * `mimeType` beside the value. Agency's attachment shape keeps it there:
 * `{ kind: "base64", base64, mimeType }`. With neither, the marker says
 * `base64`.
 */
export declare const omitBinaryRule: ScrubRule;
/** The rules every statelog event goes through, in order: the redact tag
 *  first, so a redacted picture shows its redaction marker, then binary data. */
export declare function statelogScrubRules(globals: GlobalStore | undefined): ScrubRule[];
/** The fields every statelog line has. The rules apply to `data` alone. */
export type StatelogEnvelope = {
    format_version: number;
    trace_id: string;
    project_id: string;
    span_id: string | null;
    parent_span_id: string | null;
    data: Record<string, unknown>;
};
/**
 * Serialize an event in one `JSON.stringify`. The scrub rules see only `data`,
 * so a pathological redaction, such as a tag on the number 1, can never blank
 * an envelope field such as `format_version`.
 */
export declare function stringifyStatelogEvent(envelope: StatelogEnvelope, rules: readonly ScrubRule[]): string;
export {};