Added dragging of circle

src/main.js

@@ -2,13 +2,16 @@
 import { initRepo, addCircle, addTriangle, moveShape } from "./docManager.js"
 import { drawAllShapesOnCanvas } from "./canvasManager.js"
 
+let isDragging = false;
+let selectedShapeId = null;
+let offsetX = 0;
+let offsetY = 0;
+
 const canvas = document.getElementById("shapesCanvas")
 
 // 1. Init the repo & document handle
 const handle = initRepo()
-// TODO is the whenReady() needed ?
-// await handle.whenReady()
-
+await handle.whenReady()
 
 // 2. Subscribe so we can re-render whenever doc changes
 // Listen for 'change' events
@@ -25,11 +28,69 @@ const addTriangleButton = document.getElementById("addTriangleButton");
 addCircleButton.addEventListener("click", () => {
   // z. B. zufällige Position/Radius
   addCircle(100, 100, 30);
-  // TODO render();
 });
 
 addTriangleButton.addEventListener("click", () => {
   // z. B. zufällige Koordinaten
   addTriangle( 200, 200, 220, 220, 180, 220);
-  // TODO render();
 });
+
+// Mousedown: Prüfen, ob wir auf ein Shape klicken
+canvas.addEventListener("mousedown", (e) => {
+  const { offsetX: mouseX, offsetY: mouseY } = e;
+
+  // 1. Shape unter Maus suchen
+  const clickedShape = getShapeAtCoordinates(mouseX, mouseY);
+  console.log("Clicked shape:",clickedShape)
+
+  if (clickedShape) {
+    isDragging = true;
+    selectedShapeId = clickedShape.id;
+
+    // Damit das Shape unter dem Mauszeiger bleibt, merken wir uns den "Offset"
+    offsetX = mouseX - clickedShape.x;
+    offsetY = mouseY - clickedShape.y;
+  }
+});
+
+// Mousemove: Shape verschieben, sofern dragging aktiv ist
+canvas.addEventListener("mousemove", (e) => {
+  if (!isDragging || selectedShapeId === null) return;
+
+  const { offsetX: mouseX, offsetY: mouseY } = e;
+
+  // Neue Koordinaten berechnen
+  const newX = mouseX - offsetX;
+  const newY = mouseY - offsetY;
+
+  // Achtung: Hier könnte man Throttling/RAF implementieren
+  moveShape(selectedShapeId, newX, newY);
+});
+
+// Mouseup: Dragging beenden
+canvas.addEventListener("mouseup", () => {
+  isDragging = false;
+  selectedShapeId = null;
+});
+
+/**
+ * Gibt das Shape zurück, das die Koordinaten (mx, my) enthält/berührt
+ * (Vereinfacht: nur für Kreise)
+ */
+function getShapeAtCoordinates(mx, my) {
+  const doc = handle.docSync()
+  console.log("DOC IN GETSHAPEATCOORDIATES:",doc)
+  // Hier nur ein einfacher Loop durch alle Kreise
+  for (let shape of doc.shapes) {
+    if (shape.type === "circle") {
+      const dist = Math.sqrt((mx - shape.x) ** 2 + (my - shape.y) ** 2);
+      console.log("calculated distance and radius:",dist,shape.radius)
+      if (dist <= shape.radius) {
+        console.log("Found shape:",shape)
+        return shape;
+      }
+    }
+    // ggf. erweitern für Dreiecke oder andere Formen
+  }
+  return null;
+}