/**
 * Copyright (c) 2023-2024 DeepSeek.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

// ==UserScript==
// @name         Kelpy Codos
// @namespace    https://github.com/Keldos-Li/Kelpy-Codos
// @version      1.0.5
// @author       Keldos; https://keldos.me/
// @description  Add copy button to PRE tags before CODE tag, for Chuanhu ChatGPT especially.
//               Based on Chuanhu ChatGPT version: ac04408 (2023-3-22)
// @license      GPL-3.0
// @grant        none
// ==/UserScript==

(function () {
  "use strict";

  function addCopyButton(pre) {
    var code = pre.querySelector("code");
    if (!code) {
      return; // 如果没有找到 <code> 元素，则不添加按钮
    }
    var firstChild = code.firstChild;
    if (!firstChild) {
      return; // 如果 <code> 元素没有子节点，则不添加按钮
    }
    var button = document.createElement("button");
    button.textContent = "\uD83D\uDCCE"; // 使用 📎 符号作为“复制”按钮的文本
    button.style.position = "relative";
    button.style.float = "right";
    button.style.fontSize = "1em"; // 可选：调整按钮大小
    button.style.background = "none"; // 可选：去掉背景颜色
    button.style.border = "none"; // 可选：去掉边框
    button.style.cursor = "pointer"; // 可选：显示指针样式
    button.addEventListener("click", function () {
      var range = document.createRange();
      range.selectNodeContents(code);
      range.setStartBefore(firstChild); // 将范围设置为第一个子节点之前
      var selection = window.getSelection();
      selection.removeAllRanges();
      selection.addRange(range);

      try {
        var success = document.execCommand("copy");
        if (success) {
          button.textContent = "\u2714";
          setTimeout(function () {
            button.textContent = "\uD83D\uDCCE"; // 恢复按钮为“复制”
          }, 2000);
        } else {
          button.textContent = "\u2716";
        }
      } catch (e) {
        console.error(e);
        button.textContent = "\u2716";
      }

      selection.removeAllRanges();
    });
    code.insertBefore(button, firstChild); // 将按钮插入到第一个子元素之前
  }

  function handleNewElements(mutationsList, observer) {
    for (var mutation of mutationsList) {
      if (mutation.type === "childList") {
        for (var node of mutation.addedNodes) {
          if (node.nodeName === "PRE") {
            addCopyButton(node);
          }
        }
      }
    }
  }

  var observer = new MutationObserver(handleNewElements);
  observer.observe(document.documentElement, {
    childList: true,
    subtree: true,
  });

  document.querySelectorAll("pre").forEach(addCopyButton);
})();