clipboard.js

var clipboardContent = {}; // XXX: hidden state

function cloneObject(obj) {
  return JSON.parse(JSON.stringify(obj));
}

function makeNewId(label) {
  var num = 60466176; // 36^5
  num = Math.floor(Math.random() * num);
  var id = label + '_' + num.toString(36);
  return id;
}

function copy(graph, keys) {
  //Duplicate all the nodes before putting them in clipboard
  //this will make this work also with cut/Paste and once we
  //decide if/how we will implement cross-document copy&paste will work there too
  clipboardContent = {nodes:[], edges:[]};
  var map = {};
  var i, len;
  for (i = 0, len = keys.length; i < len; i++) {
    var node = graph.getNode(keys[i]);
    var newNode = cloneObject(node);
    newNode.id = makeNewId(node.component);
    clipboardContent.nodes.push(newNode);
    map[node.id] = newNode.id;
  }
  for (i = 0, len = graph.edges.length; i < len; i++) {
    var edge = graph.edges[i];
    var fromNode = edge.from.node;
    var toNode = edge.to.node;
    if (map.hasOwnProperty(fromNode) && map.hasOwnProperty(toNode)) {
      var newEdge = cloneObject(edge);
      newEdge.from.node = map[fromNode];
      newEdge.to.node = map[toNode];
      clipboardContent.edges.push(newEdge);
    }
  }

}

function paste(graph) {
  var map = {};
  var pasted = {nodes:[], edges:[]};
  var i, len;
  for (i = 0, len = clipboardContent.nodes.length; i < len; i++) {
    var node = clipboardContent.nodes[i];
    var meta = cloneObject(node.metadata);
    meta.x += 36;
    meta.y += 36;
    var newNode = graph.addNode(makeNewId(node.component), node.component, meta);
    map[node.id] = newNode.id;
    pasted.nodes.push(newNode);
  }
  for (i = 0, len = clipboardContent.edges.length; i < len; i++) {
    var edge = clipboardContent.edges[i];
    var newEdgeMeta = cloneObject(edge.metadata);
    var newEdge;
    if (edge.from.hasOwnProperty('index') || edge.to.hasOwnProperty('index')) {
      // One or both ports are addressable
      var fromIndex = edge.from.index || null;
      var toIndex = edge.to.index || null;
      newEdge = graph.addEdgeIndex(map[edge.from.node], edge.from.port, fromIndex, map[edge.to.node], edge.to.port, toIndex, newEdgeMeta);
    } else {
      newEdge = graph.addEdge(map[edge.from.node], edge.from.port, map[edge.to.node], edge.to.port, newEdgeMeta);
    }
    pasted.edges.push(newEdge);
  }
  return pasted;
}

module.exports = {
  copy: copy,
  paste: paste,
};