function _array_like_to_array(arr, len) {
    if (len == null || len > arr.length) len = arr.length;
    for(var i = 0, arr2 = new Array(len); i < len; i++)arr2[i] = arr[i];
    return arr2;
}
function _array_with_holes(arr) {
    if (Array.isArray(arr)) return arr;
}
function _iterable_to_array_limit(arr, i) {
    var _i = arr == null ? null : typeof Symbol !== "undefined" && arr[Symbol.iterator] || arr["@@iterator"];
    if (_i == null) return;
    var _arr = [];
    var _n = true;
    var _d = false;
    var _s, _e;
    try {
        for(_i = _i.call(arr); !(_n = (_s = _i.next()).done); _n = true){
            _arr.push(_s.value);
            if (i && _arr.length === i) break;
        }
    } catch (err) {
        _d = true;
        _e = err;
    } finally{
        try {
            if (!_n && _i["return"] != null) _i["return"]();
        } finally{
            if (_d) throw _e;
        }
    }
    return _arr;
}
function _non_iterable_rest() {
    throw new TypeError("Invalid attempt to destructure non-iterable instance.\\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method.");
}
function _sliced_to_array(arr, i) {
    return _array_with_holes(arr) || _iterable_to_array_limit(arr, i) || _unsupported_iterable_to_array(arr, i) || _non_iterable_rest();
}
function _unsupported_iterable_to_array(o, minLen) {
    if (!o) return;
    if (typeof o === "string") return _array_like_to_array(o, minLen);
    var n = Object.prototype.toString.call(o).slice(8, -1);
    if (n === "Object" && o.constructor) n = o.constructor.name;
    if (n === "Map" || n === "Set") return Array.from(n);
    if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _array_like_to_array(o, minLen);
}
import { useCallback, useEffect, useRef, useState } from "react";
var useSmartScrollShadow = function() {
    var sensitivity = arguments.length > 0 && arguments[0] !== void 0 ? arguments[0] : 1;
    var _useState = _sliced_to_array(useState({
        vertical: {
            hasScroll: false,
            isAtStart: true,
            isAtEnd: true
        },
        horizontal: {
            hasScroll: false,
            isAtStart: true,
            isAtEnd: true
        }
    }), 2), scrollState = _useState[0], setScrollState = _useState[1];
    var elementRef = useRef(null);
    var rafId = useRef();
    var checkScroll = useCallback(function() {
        var element = elementRef.current;
        if (!element) return;
        // 垂直方向检测
        var scrollHeight = element.scrollHeight;
        var clientHeight = element.clientHeight;
        var scrollTop = element.scrollTop;
        // 水平方向检测
        var scrollWidth = element.scrollWidth;
        var clientWidth = element.clientWidth;
        var scrollLeft = element.scrollLeft;
        setScrollState({
            vertical: {
                hasScroll: scrollHeight > clientHeight + sensitivity,
                isAtStart: scrollTop <= sensitivity,
                isAtEnd: scrollTop + clientHeight >= scrollHeight - sensitivity
            },
            horizontal: {
                hasScroll: scrollWidth > clientWidth + sensitivity,
                isAtStart: scrollLeft <= sensitivity,
                isAtEnd: scrollLeft + clientWidth >= scrollWidth - sensitivity
            }
        });
    }, [
        sensitivity
    ]);
    useEffect(function() {
        if (typeof window === 'undefined') return;
        if (typeof ResizeObserver === 'undefined') return;
        var element = elementRef.current;
        if (!element) return;
        var throttledCheck = function() {
            if (rafId.current) return;
            rafId.current = requestAnimationFrame(function() {
                checkScroll();
                rafId.current = undefined;
            });
        };
        var observer = new ResizeObserver(throttledCheck);
        observer.observe(element);
        element.addEventListener('scroll', throttledCheck, {
            passive: true
        });
        // 初始检测
        checkScroll();
        return function() {
            observer.disconnect();
            element.removeEventListener('scroll', throttledCheck);
            if (rafId.current) cancelAnimationFrame(rafId.current);
        };
    }, [
        checkScroll
    ]);
    return [
        elementRef,
        scrollState
    ];
};
export default useSmartScrollShadow;
