big cmap refactoring

static/cmap/engine/diagram-node.js

@@ -0,0 +1,48 @@
+import {
+  DiagramComponent,
+  pickAttributes,
+  validateOptionalHandler
+} from "./diagram-component.js";
+import { DrawingNode } from "./drawing-core.js";
+
+const NODE_ATTRIBUTES = [
+  "content",
+  "contentType",
+  "x",
+  "y",
+  "width",
+  "height",
+  "backgroundColor",
+  "borderColor",
+  "borderWidth",
+  "textColor"
+];
+
+/**
+ * Public rendering handle for one diagram node.
+ *
+ * DiagramEngine creates nodes and owns their lifetime. The editor uses this
+ * handle to update presentation attributes and receive completed moves.
+ */
+export class DiagramNode extends DiagramComponent {
+  constructor(engine, attributes) {
+    const component = new DrawingNode(pickAttributes(attributes, NODE_ATTRIBUTES));
+    super(engine, component, NODE_ATTRIBUTES);
+  }
+
+  /** Constrain or observe the node while it is being dragged. */
+  onMove(handler) {
+    validateOptionalHandler(handler, "move");
+    this.component.moveHandler = handler ?
+      (x, y) => handler(this, x, y) : null;
+    return this;
+  }
+
+  /** Register a callback for the end of a node drag gesture. */
+  onMoveEnd(handler) {
+    validateOptionalHandler(handler, "move-end");
+    this.component.moveEndHandler = handler ?
+      (x, y, event) => handler(this, x, y, event) : null;
+    return this;
+  }
+}