import type { BatchPhase } from '../batch/batch-progress-types.js';
import type { AutoCompactMode } from './auto-compact-modes.js';
/** Which rule decided the compaction point. */
export type BatchCompactionKind = 'silent' | 'ratio' | 'phase-boundary' | 'red-line';
/**
 * The decision, in the shape the caller acts on.
 *
 * `action` uses the same vocabulary as `evaluateAutoCompactDecision`, so a
 * caller that already handles that action handles this one.
 */
export interface BatchCompactionPoint {
    readonly kind: BatchCompactionKind;
    readonly shouldCompact: boolean;
    readonly action: 'ok' | 'soft-warn' | 'auto-compact-now' | 'red-line';
    readonly ratio: number;
    /** Whether the batch is crossing one of the two compaction boundaries. */
    readonly atBoundary: boolean;
}
/**
 * The two phase transitions that are a compaction boundary.
 *
 * ①→② is the diagnosis giving way to the topology, ③→④ the fix giving
 * way to the verification. The other two transitions (②→③, ④→done) are
 * not boundaries: neither of them is followed by a stage that reads the
 * stage before it back.
 *
 * @param fromPhase - The phase the batch was in.
 * @param toPhase - The phase the batch is in now.
 */
export declare function isBatchPhaseBoundary(fromPhase: BatchPhase, toPhase: BatchPhase): boolean;
/**
 * Decide the batch's compaction point.
 *
 * @param input.ratio - The context ratio, 0..1.
 * @param input.fromPhase - The phase the batch was in.
 * @param input.toPhase - The phase the batch is in now; the same value as
 *   `fromPhase` when no transition happened.
 * @param input.mode - The auto-compact mode; the thresholds come from it.
 */
export declare function decideBatchCompactionPoint(input: {
    readonly ratio: number;
    readonly fromPhase: BatchPhase;
    readonly toPhase: BatchPhase;
    readonly mode?: AutoCompactMode;
}): BatchCompactionPoint;