import { EventEmitter } from 'node:events';
import type { SignalSourceType, Observation, FileSystemSignalConfig, WebhookSignalConfig, ScheduleSignalConfig } from './types.js';
export interface SignalAdapter {
    readonly type: SignalSourceType;
    start(emit: (obs: Observation) => void): Promise<void>;
    stop(): Promise<void>;
}
export declare class FileWatcherAdapter implements SignalAdapter {
    readonly type: SignalSourceType;
    private watchers;
    private config;
    private debounceMs;
    private pendingChanges;
    private debounceTimer;
    constructor(config: FileSystemSignalConfig, debounceMs?: number);
    start(emit: (obs: Observation) => void): Promise<void>;
    stop(): Promise<void>;
    private flushPendingChanges;
}
export declare class WebhookAdapter implements SignalAdapter {
    readonly type: SignalSourceType;
    private server;
    private config;
    constructor(config: WebhookSignalConfig);
    start(emit: (obs: Observation) => void): Promise<void>;
    stop(): Promise<void>;
}
export declare class ScheduleAdapter implements SignalAdapter {
    readonly type: SignalSourceType;
    private timer;
    private tickCount;
    private config;
    constructor(config: ScheduleSignalConfig);
    start(emit: (obs: Observation) => void): Promise<void>;
    stop(): Promise<void>;
}
export declare class Observer extends EventEmitter {
    private adapters;
    private queue;
    private running;
    private waitResolve;
    register(adapter: SignalAdapter): void;
    start(): Promise<void>;
    stop(): Promise<void>;
    dequeue(): Promise<Observation | null>;
    get queueDepth(): number;
    get isRunning(): boolean;
}