/**
 * JSONL file logger for peaks-loop.
 *
 *
 * Default-on file logging: every peaks-loop invocation writes a
 * structured log entry to `<homedir>/.peaks/logs/peaks-loop-YYYY-MM-DD.log`
 * (UTC date stamp). One JSON object per line.
 *
 * Hard contracts enforced here:
 *  - stdout is NEVER touched by the logger (G7). Use the returned
 *    `LogLine` string and pipe it to the file only.
 *  - The log dir is created lazily on first write (G1).
 *  - File mode is 0o600 on POSIX (R3). Windows uses ACLs and the
 *    0o600 bit is a no-op there; the call is best-effort.
 *  - All write paths go through `redact` so a leaked secret can
 *    never reach disk (G6).
 *  - The log level can be overridden via `PEAKS_LOG_LEVEL` (G3) and
 *    `PEAKS_LOG_DATE_OVERRIDE` (AC2) for deterministic tests.
 *
 * No third-party deps (R1): `fs.appendFileSync` + `JSON.stringify`
 * is enough; pino/winston are NOT pulled in.
 */
import { dirname } from 'node:path';
export type LogLevel = 'debug' | 'info' | 'warn' | 'error';
export type LogEntry = {
    ts: string;
    level: LogLevel;
    command: string;
    msg: string;
    sessionId?: string;
    version?: string;
    batchId?: string;
    data?: Record<string, unknown>;
};
/**
 * Returns the canonical log directory. On Windows, `homedir()` is
 * `%USERPROFILE%`; on macOS / Linux, `$HOME`. The path is the
 * user-global `~/.peaks/logs/` — never inside a project tree (NG6).
 */
export declare function resolveLogDir(): string;
/**
 * Returns the UTC date-stamped file name. `date` is injectable so
 * tests can pin the date without monkey-patching `Date`.
 */
export declare function buildLogFileName(date: Date): string;
export type WriteLogOptions = {
    /** Override the clock for deterministic tests. Defaults to `new Date()`. */
    now?: () => Date;
    /**
     * Override the log dir for tests. Defaults to `resolveLogDir()`.
     * Allows the test harness to redirect to a temp dir without
     * monkey-patching `os.homedir()`.
     */
    dirOverride?: string;
    /**
     * Override the date used for the file name + entry `ts`. The PRD
     * AC2 contract is `PEAKS_LOG_DATE_OVERRIDE=YYYY-MM-DD`; the
     * program-level flag plumbing in `program.ts` reads it and passes
     * it down. The `now` option still drives the `ts` field, so the
     * caller MUST pass a matching `Date` for the AC2 invariant.
     */
    dateOverride?: string;
};
/**
 * Write a single JSONL log entry. Returns the absolute file path
 * the entry was written to, or `null` when the entry was filtered
 * out by the current log level.
 *
 * Failures inside the logger (mkdir, appendFile, chmod) are caught
 * and swallowed: a logger that takes down the CLI is worse than a
 * logger that drops a line. The swallow is intentional per the PRD
 * non-goals (NG1: no remote ship; the user only ever sees a file
 * they read directly).
 */
export declare function writeLogEntry(entry: LogEntry, opts?: WriteLogOptions): string | null;
export type ReadLogOptions = {
    now?: () => Date;
    dirOverride?: string;
    dateOverride?: string;
};
/**
 * Read the current day's log file and return all parseable JSON
 * entries. Malformed lines are skipped (the on-disk file is JSONL,
 * but a crash mid-write can leave a partial line; we don't want
 * that to break `peaks log tail`).
 */
export declare function readLogEntries(opts?: ReadLogOptions): LogEntry[];
/**
 * Print a log line to stderr IF the current process is in verbose
 * mode (`--verbose` / `-v` / `PEAKS_LOG_LEVEL=debug`). This is the
 * G3 opt-in channel: by default, stderr stays clean so the CLI's
 * `--json` envelope is not contaminated.
 *
 * Returns `true` when the line was written; `false` otherwise. The
 * caller can use the boolean to detect silent-failure patterns (a
 * `peaks log tail` that prints nothing when the user expected a
 * verbose stream).
 */
export declare function maybeWriteStderr(entry: LogEntry, opts: {
    verbose: boolean;
}): boolean;
export { dirname };