import type { LogLevel } from './runtime-flags.js';
export declare function stripAnsi(str: string): string;
/** Generates a filename-safe ISO timestamp + PID string. */
export declare function generateLogFilename(): string;
/**
 * Deletes log files older than `maxAgeMs` from the given directory.
 * Errors are logged to stderr but never thrown.
 */
export declare function cleanupOldLogs(logDir: string, maxAgeMs?: number): void;
export interface FileLoggerOptions {
    /** The directory for log files. Defaults to `~/.slicc/logs/`. */
    logDir?: string;
    /** Minimum level for log entries. Defaults to `'info'`. */
    logLevel?: LogLevel;
    /** When true, monkey-patches console to tee all output. */
    devMode?: boolean;
    /** Run 7-day cleanup on init. Defaults to true. */
    cleanup?: boolean;
}
export declare class FileLogger {
    readonly logDir: string;
    readonly logFile: string;
    private fd;
    private logLevel;
    private devMode;
    private origConsole;
    constructor(options?: FileLoggerOptions);
    /** Write a structured log entry. Respects log level filtering. */
    log(level: LogLevel, message: string, data?: Record<string, unknown>): void;
    /** Flush and close the log file. Safe to call multiple times. */
    close(): void;
    private installConsoleTee;
    private restoreConsole;
    private writeLine;
    private onExit;
    private registerShutdownHandlers;
    private deregisterShutdownHandlers;
}