simulate-trello-clipboard.js

// copy code from http://stackoverflow.com/questions/17527870/how-does-trello-access-the-users-clipboard/17528590
(function() {
  var utils = {
    nodeName: function(node, name){
      return !!(node.nodeName.toLowerCase() === name)
    }
  };
  
  var textareaId = 'simulate-trello-clipboard'
    , containerId = textareaId + '-container'
    , container
    , textarea;

  var createTextarea = function(){
    container = document.querySelector('#' + containerId)
    if (!container) {
      container = document.createElement('div')
      container.id = containerId
      container.setAttribute('style', [
        , 'position: fixed;'
        , 'left: 0px;'
        , 'top: 0px;'
        , 'width: 0px;'
        , 'height: 0px;'
        , 'z-index: 100;'
        , 'opacity: 0;'
      ].join(''))
      document.body.appendChild(container)
    }
    container.style.display = 'block'
    textarea = document.createElement('textarea')
    textarea.setAttribute('style', [
      , 'width: 1px;'
      , 'height: 1px;'
      , 'padding: 0px;'
    ].join(''))
    textarea.id = textareaId
    container.innerHTML = ''
    container.appendChild(textarea)
    textarea.appendChild(document.createTextNode(location.href))
    textarea.focus()
    textarea.select()
  };

  var keyDownMonitor = function(e){
    var code = e.keyCode || e.which;
    if (!(e.ctrlKey || e.metaKey) || code !== 67) {
      return
    }
    var target = e.target
    if (utils.nodeName(target, 'textarea')
      || utils.nodeName(target, 'input')) {
      return
    }
    if (window.getSelection
      && window.getSelection()
      && window.getSelection().toString()) {
      return
    }
    if (document.selection
      && document.selection.createRange().text) {
      return
    }
    setTimeout(createTextarea, 0)
  };

  var keyUpMonitor = function(e){
    var code = e.keyCode || e.which;
    if (e.target.id !== textareaId || code !== 67) { return }
    container.style.display = 'none'
  };

  document.addEventListener('keydown', keyDownMonitor);
  document.addEventListener('keyup', keyUpMonitor);
  
})();