import EventEmitter from '@antv/event-emitter';
import { IPointerEvent } from '../types';
/**
 * <zh/> 表示指针位置的点坐标
 *
 * <en/> Represents the coordinates of a pointer position
 */
export interface PointerPoint {
    x: number;
    y: number;
    pointerId: number;
}
/**
 * <zh/> 捏合事件参数
 *
 * <en/> Pinch event parameters
 * @remarks
 * <zh/> 包含与捏合手势相关的参数，当前支持缩放比例，未来可扩展中心点坐标、旋转角度等参数
 *
 * <en/> Contains parameters related to pinch gestures, currently supports scale factor,
 * can be extended with center coordinates, rotation angle etc. in the future
 */
export interface PinchEventOptions {
    /**
     * <zh/> 缩放比例因子，>1 表示放大，<1 表示缩小
     *
     * <en/> Scaling factor, >1 indicates zoom in, <1 indicates zoom out
     */
    scale: number;
}
/**
 * <zh/> 捏合手势阶段类型
 * <en/> Pinch gesture phase type
 * @remarks
 * <zh/> 包含三个手势阶段：
 * - start: 手势开始
 * - move: 手势移动中
 * - end: 手势结束
 *
 * <en/> Contains three gesture phases:
 * - pinchstart: Gesture started
 * - pinchmove: Gesture in progress
 * - pinchend: Gesture ended
 */
export type PinchEvent = 'pinchstart' | 'pinchmove' | 'pinchend';
/**
 * <zh/> 捏合手势回调函数类型
 *
 * <en/> Pinch gesture callback function type
 * @param event - <zh/> 原始指针事件对象 | <en/> Original pointer event object
 * @param options - <zh/> 捏合事件参数对象 | <en/> Pinch event parameters object
 */
export type PinchCallback = (event: IPointerEvent, options: PinchEventOptions) => void;
/**
 * <zh/> 捏合手势处理器
 *
 * <en/> Pinch gesture handler
 * @remarks
 * <zh/> 处理双指触摸事件，计算缩放比例并触发回调。通过跟踪两个触摸点的位置变化，计算两点间距离变化率来确定缩放比例。
 *
 * <en/> Handles two-finger touch events, calculates zoom ratio and triggers callbacks. Tracks position changes of two touch points to determine zoom ratio based on distance variation.
 */
export declare class PinchHandler {
    private phase;
    /**
     * <zh/> 是否处于 Pinch 阶段
     *
     * <en/> Whether it is in the Pinch stage
     */
    static isPinching: boolean;
    /**
     * <zh/> 当前跟踪的触摸点集合
     *
     * <en/> Currently tracked touch points collection
     */
    private pointerByTouch;
    /**
     * <zh/> 初始两点间距离
     *
     * <en/> Initial distance between two points
     */
    private initialDistance;
    private emitter;
    private static instance;
    private static callbacks;
    constructor(emitter: EventEmitter, phase: PinchEvent, callback: PinchCallback);
    private bindEvents;
    /**
     * <zh/> 更新指定指针的位置
     *
     * <en/> Update position of specified pointer
     * @param pointerId - <zh/> 指针唯一标识符 | <en/> Pointer unique identifier<sup>1</sup>
     * @param x - <zh/> 新的X坐标 | <en/> New X coordinate
     * @param y - <zh/> 新的Y坐标 | <en/> New Y coordinate
     */
    private updatePointerPosition;
    /**
     * <zh/> 处理指针按下事件
     *
     * <en/> Handle pointer down event
     * @param event - <zh/> 指针事件对象 | <en/> Pointer event object
     * @remarks
     * <zh/> 当检测到两个触摸点时记录初始距离
     *
     * <en/> Record initial distance when detecting two touch points
     */
    onPointerDown(event: IPointerEvent): void;
    /**
     * <zh/> 处理指针移动事件
     *
     * <en/> Handle pointer move event
     * @param event - <zh/> 指针事件对象 | <en/> Pointer event object
     * @remarks
     * <zh/> 当存在两个有效触摸点时计算缩放比例
     *
     * <en/> Calculate zoom ratio when two valid touch points exist
     */
    onPointerMove(event: IPointerEvent): void;
    /**
     * <zh/> 处理指针抬起事件
     *
     * <en/> Handle pointer up event
     * @param event
     * @remarks
     * <zh/> 重置触摸状态和初始距离
     *
     * <en/> Reset touch state and initial distance
     */
    onPointerUp(event: IPointerEvent): void;
    /**
     * <zh/> 销毁捏合手势相关监听
     *
     * <en/> Destroy pinch gesture listeners
     * @remarks
     * <zh/> 移除指针按下、移动、抬起事件的监听
     *
     * <en/> Remove listeners for pointer down, move, and up events
     */
    destroy(): void;
    /**
     * <zh/> 解绑指定阶段的手势回调
     * <en/> Unregister gesture callback for specific phase
     * @param phase - <zh/> 手势阶段：开始(pinchstart)/移动(pinchmove)/结束(pinchend) | <en/> Gesture phase: start/move/end
     * @param callback - <zh/> 要解绑的回调函数 | <en/> Callback function to unregister
     * @remarks
     * <zh/> 从指定阶段的回调列表中移除特定回调，当所有回调都解绑后自动销毁事件监听
     * <en/> Remove specific callback from the phase's callback list, auto-destroy event listeners when all callbacks are unregistered
     */
    off(phase: PinchEvent, callback: PinchCallback): void;
    /**
     * <zh/> 尝试销毁手势处理器
     * <en/> Attempt to destroy the gesture handler
     * @remarks
     * <zh/> 当所有阶段（开始/移动/结束）的回调列表都为空时，执行实际销毁操作
     * <en/> Perform actual destruction when all phase (pinchstart/pinchmove/pinchend) callback lists are empty
     * <zh/> 自动解除事件监听并重置单例实例
     * <en/> Automatically remove event listeners and reset singleton instance
     */
    private tryDestroy;
}