// ==UserScript==
// @name         📕无动画全屏翻页丨墨水屏一键翻页丨保留比例翻页丨自定义比例
// @version      1.1
// @description  👍忽略滑动动画，快速切换页面，可以到「脚本菜单」中进行进一步修改。
// @author       Jingyu0123
// @match        *://*/*
// @license MIT
// @grant        GM_getValue
// @grant        GM_setValue
// @grant        GM_registerMenuCommand
// @grant        GM_unregisterMenuCommand
// @namespace https://greasyfork.org/users/1292046
// @downloadURL none
// ==/UserScript==
(function() {
    'use strict';

    var usePgUpPgDn = GM_getValue('usePgUpPgDn', true);
    var reservedHeightPercentage = GM_getValue('reservedHeightPercentage', 0);

    window.addEventListener('keydown', function(event) {
        const screenHeight = window.innerHeight;
        const reservedHeight = screenHeight * reservedHeightPercentage / 100;
        if (usePgUpPgDn && (event.key === 'PageDown' || event.key === 'PageUp')) {
            const direction = event.key === 'PageDown' ? 1 : -1;
            window.scrollBy(0, direction * (screenHeight - reservedHeight));
            event.preventDefault();
        } else if (!usePgUpPgDn && (event.key === 'ArrowDown' || event.key === 'ArrowUp')) {
            const direction = event.key === 'ArrowDown' ? 1 : -1;
            window.scrollBy(0, direction * (screenHeight - reservedHeight));
            event.preventDefault();
        }
    });

    function setUsePgUpPgDn(value) {
        usePgUpPgDn = value;
        GM_setValue('usePgUpPgDn', value);
    }

    function setReservedHeightPercentage(value) {
        reservedHeightPercentage = value;
        GM_setValue('reservedHeightPercentage', value);
    }

    GM_registerMenuCommand('使用 PgUp PgDn 进行翻页', function() {
        setUsePgUpPgDn(true);
    });

    GM_registerMenuCommand('使用 Arrow keys 进行翻页', function() {
        setUsePgUpPgDn(false);
    });

    GM_registerMenuCommand('不保留翻页', function() {
        setReservedHeightPercentage(0);
    });

    GM_registerMenuCommand('保留10%翻页', function() {
        setReservedHeightPercentage(10);
    });

    GM_registerMenuCommand('保留20%翻页', function() {
        setReservedHeightPercentage(20);
    });

})();