import type { DisplacementVector, FusedPosition, FusionEngineConfig, FusionEventPayloads, PositionAnchor } from './types';
import { SensorRegistry } from '../sensors/sensor-registry';
import { PubSub } from '@packages/internal/common/pubsub';
import { HeadingFusionFilter } from './algorithms/heading-filter';
import { MultiSensorEKF } from './algorithms/multi-sensor-ekf';
import { type AnchorState } from './anchor-state';
/**
 * Multi-sensor fusion engine that combines position updates from multiple sources.
 *
 * Uses an Extended Kalman Filter (EKF) for position fusion with:
 * - Confidence-weighted measurements (high confidence = more influence)
 * - Half-life decay of old estimates (uncertainty grows over time)
 * - Hybrid anchor behavior (anchor-only period, then transition to GPS)
 *
 * Heading fusion uses a separate complementary filter combining compass and gyroscope.
 */
export declare class FusionEngine extends PubSub<FusionEventPayloads> {
    #private;
    constructor(registry: SensorRegistry, config?: Partial<FusionEngineConfig>);
    /**
     * Get the current fusion configuration.
     */
    get config(): Readonly<FusionEngineConfig>;
    /**
     * Get the current anchor state.
     * @param nowMs - Current timestamp (defaults to Date.now())
     */
    getAnchorState(nowMs?: number): AnchorState;
    /**
     * Get the current position anchor if one is set and not expired.
     */
    get anchor(): Readonly<PositionAnchor> | undefined;
    /**
     * Get the current accumulated displacement from the anchor in meters.
     * Returns (0, 0) if no anchor is set or no movement has occurred.
     */
    get displacement(): Readonly<DisplacementVector>;
    /**
     * Set an absolute position anchor from a calibration source (VPS, AI Localizer).
     * When an anchor is active, it provides the absolute position and other sensors
     * can provide relative updates from this reference point.
     *
     * @param anchor - The position anchor to set
     * @param configOverride - Optional config overrides for this anchor (e.g., anchorOnlyPeriodMs)
     */
    setAnchor(anchor: PositionAnchor, configOverride?: Partial<Pick<FusionEngineConfig, 'anchorOnlyPeriodMs'>>): void;
    /**
     * Clear the current position anchor and accumulated displacement.
     */
    clearAnchor(): void;
    /**
     * Reset the EKF state.
     * Call on floor changes or large position jumps.
     */
    resetEKF(): void;
    /**
     * Reset the heading fusion filter state.
     * Call on floor changes or when heading should be re-initialized.
     */
    resetHeadingFilter(): void;
    /**
     * Get the heading fusion filter for configuration.
     * @internal Used by debug tools for runtime tuning.
     */
    get headingFilter(): HeadingFusionFilter;
    /**
     * Get the multi-sensor EKF for inspection.
     * @internal Used by debug tools for runtime inspection.
     */
    get ekf(): MultiSensorEKF;
    /**
     * Get the last fused position.
     * @returns The last fused position, or undefined if none available
     */
    getLastPosition(): FusedPosition | undefined;
    destroy(): void;
}