// ==UserScript==
// @name 防止未经授权的自动复制
// @version 10
// @author ChatGPT
// @description 在非选词复制时显示小红点提示用户以防止未经授权的自动复制。
// @grant GM_setClipboard
// @run-at document-start
// @match *://*/*
// @namespace https://greasyfork.org/users/452911
// @downloadURL none
// ==/UserScript==

(function() {
  'use strict';

  let hasCopied = false;
  let timeoutId = null;

  const handleCopy = function(event) {
    event.preventDefault();
    const selection = window.getSelection().toString();
    if (!hasCopied) {
      hasCopied = true;
      const dot = document.createElement('div');
      dot.style.width = '20px';
      dot.style.height = '20px';
      dot.style.zIndex = '9999';
      dot.style.background = 'red';
      dot.style.borderRadius = '50%';
      dot.style.position = 'fixed';
      dot.style.top = '50%';
      dot.style.right = '10px';
      dot.style.transform = 'translateY(-50%)';
      dot.style.cursor = 'pointer';
      dot.addEventListener('click', function() {
        const shouldCopy = confirm('是否复制？\n' + selection);
        if (shouldCopy) {
          if (typeof GM_setClipboard === "function") {
            GM_setClipboard(selection);
          } else {
            copyToClipboard(selection);
          }
        }
        document.body.removeChild(dot);
        hasCopied = false;
      });
      document.body.appendChild(dot);

      timeoutId = setTimeout(function() {
        document.body.removeChild(dot);
        hasCopied = false;
        timeoutId = null;
      }, 2000); // 设置延时时间，单位为毫秒
    }
  };

  const handleSelectionChange = function() {
    const selection = window.getSelection().toString();
    if (selection.length === 0) {
      document.addEventListener('copy', handleCopy);
    } else {
      document.removeEventListener('copy', handleCopy);
    }
  };

  const copyToClipboard = function(text) {
    const textArea = document.createElement('textarea');
    textArea.value = text;
    document.body.appendChild(textArea);
    textArea.select();
    document.execCommand('copy');
    document.body.removeChild(textArea);
  };

  // 重写 navigator.clipboard.writeText
  navigator.clipboard.writeText = function(text) {
    return new Promise((resolve, reject) => {
      const textArea = document.createElement('textarea');
      textArea.value = text;
      document.body.appendChild(textArea);
      textArea.select();
      try {
        const successful = document.execCommand('copy');
        if (successful) {
          resolve();
        } else {
          reject(new Error('Failed to copy text to clipboard'));
        }
      } catch (err) {
        reject(err);
      } finally {
        document.body.removeChild(textArea);
      }
    });
  };

  document.addEventListener('copy', handleCopy);
  document.addEventListener('selectionchange', handleSelectionChange);

  // 在页面卸载前清除延时器
  window.addEventListener('beforeunload', function() {
    if (timeoutId) {
      clearTimeout(timeoutId);
    }
  });
})();