feat: Refactor document drag initiation and state management with new session handling and geometry utilities. (slightly broken)

frontend/src/desktop/utils/layoutUtils.ts

@@ -0,0 +1,35 @@
+export interface CardBounds {
+    minX: number;
+    maxX: number;
+    minY: number;
+    maxY: number;
+}
+
+export interface ComputeBoundsOptions {
+    width: number;
+    height: number;
+    canvasWidth: number;
+    canvasHeight: number;
+    padding: number;
+    shelfWidth?: number;
+}
+
+export const computeCardBounds = ({
+    width,
+    height,
+    canvasWidth,
+    canvasHeight,
+    padding,
+    shelfWidth = 0,
+}: ComputeBoundsOptions): CardBounds => {
+    const halfW = width / 2;
+    const halfH = height / 2;
+    const shelfOffset = Math.max(shelfWidth, 0);
+
+    return {
+        minX: padding + halfW,
+        maxX: Math.max(padding + halfW, canvasWidth - shelfOffset - padding - halfW),
+        minY: padding + halfH,
+        maxY: Math.max(padding + halfH, canvasHeight - padding - halfH),
+    };
+};