// ==UserScript==
// @name         元素选择器
// @namespace    http://tampermonkey.net/
// @version      1.0.0
// @description  通过鼠标右键选择元素
// @author       xuanzai
// @match        *://*/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=tampermonkey.net
// @license MIT
// @downloadURL https://update.greasyfork.icu/scripts/465641/%E5%85%83%E7%B4%A0%E9%80%89%E6%8B%A9%E5%99%A8.user.js
// @updateURL https://update.greasyfork.icu/scripts/465641/%E5%85%83%E7%B4%A0%E9%80%89%E6%8B%A9%E5%99%A8.meta.js
// ==/UserScript==

(function () {
  'use strict';
  // 通过DOM元素获取元素选择器
  let selector, x, y, scrollTop, visible = false
  function getSelectorRes(el, deep = false) {
    if (!(el instanceof Element)) return
    const path = []
    let deepIndex = 0
    // 仅选三层
    while (el.nodeType === Node.ELEMENT_NODE) {
      if (!deep && deepIndex > 2) break
      let selector = el.nodeName.toLowerCase()
      if (el.id) {
        selector += '#' + el.id
        path.unshift(selector)
        break
      } else {
        if (!deep && el.className && typeof el.className === 'string') {
          selector += '.' + el.className.split(' ').filter(val => val.replace(/\s+/, '')).join('.')
        }
        let sib = el,
          nth = 1
        while ((sib = sib.previousElementSibling)) {
          if (sib.nodeName.toLowerCase() == selector) nth++
        }
        if (nth != 1) selector += ':nth-of-type(' + nth + ')'
      }
      path.unshift(selector)
      el = el.parentNode
      deepIndex++
      console.log('deepIndex', deepIndex)
    }
    return !deep ? path.join(' ') : path.join('>')
  }
  // 写入剪贴板
  function copyToClipboard(text) {
    var input = document.createElement('input');
    input.setAttribute('value', text);
    document.body.appendChild(input);
    input.select();
    if (document.execCommand('copy')) {
      document.execCommand('copy');
    }
    document.body.removeChild(input);
  }
  // 获取当前鼠标指向的元素
  function get_current_element(event) {
    x = event.clientX, y = event.clientY;
    let element = document.elementFromPoint(x, y);
    console.log('x:', x, 'y:', y)
    return element
  }
  // 鼠标点击事件
  function track_mouse(event) {
    if (event.button == 2) {
      if (visible) return
      visible = true
      var elementMouseIsOver = get_current_element(event)
      console.log('当前鼠标指向的元素是：', elementMouseIsOver)
      scrollTop = getScrollTop()
      selector = getSelectorRes(elementMouseIsOver)
      console.log('result:', selector)
      if (elementMouseIsOver !== document.querySelector(selector)) {
        selector = getSelectorRes(elementMouseIsOver, true)
      }
      const matchResult = elementMouseIsOver
      if (matchResult) {
        console.log(document.querySelector(selector))
        showConfirm()
      } else {
        // 写入剪贴板
        console.log('未匹配到元素')
      }
    }
    // 鼠标左键点击，不是弹窗区域就关闭弹窗
    if (event.button == 0) {
      var elementMouseIsOver = get_current_element(event)
      const confirm = document.querySelector('#confirm')
      if (confirm) {
        if (confirm.contains(elementMouseIsOver)) return
        removeConfirm()
      }
    }
  }

  // 获取页面滚动条高度
  function getScrollTop() {
    var scroll_top = 0;
    if (document.documentElement && document.documentElement.scrollTop) {
      scroll_top = document.documentElement.scrollTop;
    }
    else if (document.body) {
      scroll_top = document.body.scrollTop;
    }
    return scroll_top;
  }

  // 选择按钮的弹窗
  function showConfirm() {
    const confirm = document.createElement('div')
    confirm.id = 'confirm'
    confirm.innerHTML = `
    <div class="confirm">
      <div class="confirm-content">
        <h3 style="text-align: center">当前鼠标选中的值</h3>
        <p>元素选择器 or x/y坐标 or 滚动条高度(scrollTop)？</p>
      </div>
      <div class="confirm-btn">
        <button class="btn confirm-btn-cancel">复制选择器</button>
        <button class="btn confirm-btn-ok">复制x、y坐标</button>
        <button class="btn confirm-btn-scroll">复制scrollTop</button>
      </div>
    </div>
  `
    confirm.style.cssText = `
    position: fixed;
    top: 40%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: #000;
    color: #fff;
    padding: 10px 16px;
    font-size: 18px;
    font-weight: bold;
    border-radius: 5px;
    z-index: 9999;
    opacity: 1;
  `
    document.body.appendChild(confirm)
    const buttonGroup = confirm.querySelector('.confirm-btn')
    const cancel = confirm.querySelector('.confirm-btn-cancel')
    const ok = confirm.querySelector('.confirm-btn-ok')
    const scroll = confirm.querySelector('.confirm-btn-scroll')
    buttonGroup.style.cssText = `
    display: flex;
    justify-content: space-around;
    gap: 10px;
    margin: 10px;
  `
    for (let i = 0; i < buttonGroup.children.length; i++) {
      buttonGroup.children[i].style.cssText = `
      padding: 5px 10px;
      border-radius: 5px;
      color: #000;
      opacity: 1;
      background: #fff`
    }
    cancel.addEventListener('click', () => {
      copyToClipboard(selector)
      removeConfirm()
    })
    ok.addEventListener('click', () => {
      copyToClipboard(`${x} ${y}`)
      removeConfirm()
    })
    scroll.addEventListener('click', () => {
      copyToClipboard(scrollTop)
      removeConfirm()
    })
  }

  // 关闭弹窗
  function removeConfirm() {
    if (!visible) return
    document.querySelector('#confirm').remove()
    visible = false
  }

  // 监听键盘esc键
  document.onkeydown = function (e) {
    if (e.keyCode === 27) {
      removeConfirm()
    }
  }

  window.oncontextmenu = function (e) {
    e.preventDefault()
  }
  window.onmousedown = track_mouse
  // Your code here...
})();