// ==UserScript==
// @name         全局粒子特效开关
// @namespace    http://tampermonkey.net/
// @version      1.0
// @description  页面顶部悬浮开关，一键开启/关闭全屏粒子特效
// @author       You
// @match        *://*/*
// @grant        GM_addStyle
// ==/UserScript==

(function() {
    'use strict';

    // 样式
    GM_addStyle(`
        #particleToggleBox {
            position: fixed;
            top: 12px;
            left: 50%;
            transform: translateX(-50%);
            z-index: 999999;
            background: rgba(0,0,0,0.65);
            padding: 6px 14px;
            border-radius: 99px;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        #particleToggleBox span {
            color: #fff;
            font-size: 13px;
        }
        #particleSwitch {
            width: 42px;
            height: 22px;
            background: #666;
            border-radius: 22px;
            position: relative;
            cursor: pointer;
            transition: 0.3s;
        }
        #particleSwitch::after {
            content: '';
            width: 18px;
            height: 18px;
            background: white;
            border-radius: 50%;
            position: absolute;
            top: 2px;
            left: 2px;
            transition: 0.3s;
        }
        #particleSwitch.active {
            background: #40a9ff;
        }
        #particleSwitch.active::after {
            left: 22px;
        }
        #particlesCanvas {
            position: fixed;
            top: 0;
            left: 0;
            width: 100vw;
            height: 100vh;
            pointer-events: none;
            z-index: -1;
            display: none;
        }
    `);

    // 插入开关DOM
    const box = document.createElement('div');
    box.id = 'particleToggleBox';
    box.innerHTML = `
        <span>粒子特效</span>
        <div id="particleSwitch"></div>
    `;
    document.body.appendChild(box);

    // 画布
    const canvas = document.createElement('canvas');
    canvas.id = 'particlesCanvas';
    document.body.appendChild(canvas);
    const ctx = canvas.getContext('2d');

    let w, h;
    let particles = [];
    let animateId = null;
    const switchEl = document.getElementById('particleSwitch');

    // 窗口尺寸适配
    function resize() {
        w = canvas.width = window.innerWidth;
        h = canvas.height = window.innerHeight;
    }
    resize();
    window.addEventListener('resize', resize);

    // 粒子类
    class Particle {
        constructor() {
            this.x = Math.random() * w;
            this.y = Math.random() * h;
            this.r = Math.random() * 1.2 + 0.3;
            this.speedX = Math.random() * 0.6 - 0.3;
            this.speedY = Math.random() * 0.6 - 0.3;
            this.alpha = Math.random() * 0.5 + 0.2;
        }
        update() {
            this.x += this.speedX;
            this.y += this.speedY;
            if (this.x < 0) this.x = w;
            if (this.x > w) this.x = 0;
            if (this.y < 0) this.y = h;
            if (this.y > h) this.y = 0;
        }
        draw() {
            ctx.beginPath();
            ctx.arc(this.x, this.y, this.r, 0, Math.PI * 2);
            ctx.fillStyle = `rgba(130, 190, 255, ${this.alpha})`;
            ctx.fill();
        }
    }

    // 初始化粒子
    function initParticles(count = 120) {
        particles = [];
        for (let i = 0; i < count; i++) {
            particles.push(new Particle());
        }
    }

    // 渲染动画
    function render() {
        ctx.clearRect(0, 0, w, h);
        particles.forEach(p => {
            p.update();
            p.draw();
        });
        animateId = requestAnimationFrame(render);
    }

    // 开关点击事件
    switchEl.onclick = () => {
        const isOn = switchEl.classList.contains('active');
        if (!isOn) {
            // 开启粒子
            switchEl.classList.add('active');
            canvas.style.display = 'block';
            initParticles();
            render();
        } else {
            // 关闭粒子
            switchEl.classList.remove('active');
            canvas.style.display = 'none';
            cancelAnimationFrame(animateId);
        }
    };

})();