/** Supported log severity levels. */
export type LogSeverity = 'error' | 'warn' | 'info' | 'debug';
/** All severity levels in descending order of importance. */
export declare const ALL_SEVERITIES: LogSeverity[];
/**
 * Detect the severity level of a single log line.
 *
 * Supports common structured and unstructured log formats:
 * - JSON fields: "level":"error", "severity":"warning"
 * - Key-value pairs: level=error, severity=ERROR
 * - Bracketed tokens: [ERROR], [WARN], [WARNING], [INFO], [DEBUG]
 * - Space-delimited tokens (Go/Python): ERROR , WARNING , INFO , DEBUG
 *
 * @returns The detected severity, or null if none is found.
 */
export declare function detectSeverity(line: string): LogSeverity | null;
/**
 * Filter an array of log lines by the selected severity levels.
 *
 * Lines with no detectable severity are always included to avoid
 * hiding plain-text or structureless output.
 *
 * @param logs - The full array of log lines.
 * @param selectedSeverities - The severity levels to keep.
 * @returns The filtered array of log lines.
 */
export declare function filterLogsBySeverity(logs: string[], selectedSeverities: LogSeverity[]): string[];