feat: [cont.] support inserting multiple images (#9875)

* feat: support inserting multiple images

* Initial

* handleAppOnDrop, onImageToolbarButtonClick, pasteFromClipboard

* Initial get history working

* insertMultipleImages -> insertImages

* Bug fixes, improvements

* Remove redundant branch

* Refactor addElementsFromMixedContentPaste

* History, drag & drop bug fixes

* Update snapshots

* Remove redundant try-catch

* Refactor pasteFromClipboard

* Plain paste check in mermaid paste

* Move comment

* processClipboardData -> insertClipboardContent

* Redundant variable

* Redundant variable

* Refactor insertImages

* createImagePlaceholder -> newImagePlaceholder

* Get rid of unneeded NEVER schedule, filter out failed images

* Trigger CI

* Position placeholders before initializing

* Don't mutate scene with positionElementsOnGrid, captureUpdate: CaptureUpdateAction.IMMEDIATELY

* Comment

* Move positionOnGrid out of file

* Rename file

* Get rid of generic

* Initial tests

* More asserts, test paste

* Test image tool

* De-duplicate

* Stricter assert, move rest of logic outside of waitFor

* Modify history tests

* De-duplicate update snapshots

* Trigger CI

* Fix package build

* Make setupImageTest more explicit

* Re-introduce generic to use latest placeholder versions

* newElementWith instead of mutateElement to delete failed placeholder

* Insert failed images separately with CaptureUpdateAction.NEVER

* Refactor

* Don't re-order elements

* WIP

* Get rid of 'never' for failed

* refactor type check

* align max file size constant

* make grid padding scale to zoom

---------

Co-authored-by: dwelle <5153846+dwelle@users.noreply.github.com>

packages/element/src/bounds.ts

@@ -1126,7 +1126,9 @@ export interface BoundingBox {
 }
 
 export const getCommonBoundingBox = (
-  elements: ExcalidrawElement[] | readonly NonDeleted<ExcalidrawElement>[],
+  elements:
+    | readonly ExcalidrawElement[]
+    | readonly NonDeleted<ExcalidrawElement>[],
 ): BoundingBox => {
   const [minX, minY, maxX, maxY] = getCommonBounds(elements);
   return {

packages/element/src/index.ts

@@ -97,6 +97,7 @@ export * from "./image";
 export * from "./linearElementEditor";
 export * from "./mutateElement";
 export * from "./newElement";
+export * from "./positionElementsOnGrid";
 export * from "./renderElement";
 export * from "./resizeElements";
 export * from "./resizeTest";

packages/element/src/positionElementsOnGrid.ts

@@ -0,0 +1,112 @@
+import { getCommonBounds } from "./bounds";
+import { type ElementUpdate, newElementWith } from "./mutateElement";
+
+import type { ExcalidrawElement } from "./types";
+
+// TODO rewrite (mostly vibe-coded)
+export const positionElementsOnGrid = <TElement extends ExcalidrawElement>(
+  elements: TElement[] | TElement[][],
+  centerX: number,
+  centerY: number,
+  padding = 50,
+): TElement[] => {
+  // Ensure there are elements to position
+  if (!elements || elements.length === 0) {
+    return [];
+  }
+
+  const res: TElement[] = [];
+  // Normalize input to work with atomic units (groups of elements)
+  // If elements is a flat array, treat each element as its own atomic unit
+  const atomicUnits: TElement[][] = Array.isArray(elements[0])
+    ? (elements as TElement[][])
+    : (elements as TElement[]).map((element) => [element]);
+
+  // Determine the number of columns for atomic units
+  // A common approach for a "grid-like" layout without specific column constraints
+  // is to aim for a roughly square arrangement.
+  const numUnits = atomicUnits.length;
+  const numColumns = Math.max(1, Math.ceil(Math.sqrt(numUnits)));
+
+  // Group atomic units into rows based on the calculated number of columns
+  const rows: TElement[][][] = [];
+  for (let i = 0; i < numUnits; i += numColumns) {
+    rows.push(atomicUnits.slice(i, i + numColumns));
+  }
+
+  // Calculate properties for each row (total width, max height)
+  // and the total actual height of all row content.
+  let totalGridActualHeight = 0; // Sum of max heights of rows, without inter-row padding
+  const rowProperties = rows.map((rowUnits) => {
+    let rowWidth = 0;
+    let maxUnitHeightInRow = 0;
+
+    const unitBounds = rowUnits.map((unit) => {
+      const [minX, minY, maxX, maxY] = getCommonBounds(unit);
+      return {
+        elements: unit,
+        bounds: [minX, minY, maxX, maxY] as const,
+        width: maxX - minX,
+        height: maxY - minY,
+      };
+    });
+
+    unitBounds.forEach((unitBound, index) => {
+      rowWidth += unitBound.width;
+      // Add padding between units in the same row, but not after the last one
+      if (index < unitBounds.length - 1) {
+        rowWidth += padding;
+      }
+      if (unitBound.height > maxUnitHeightInRow) {
+        maxUnitHeightInRow = unitBound.height;
+      }
+    });
+
+    totalGridActualHeight += maxUnitHeightInRow;
+    return {
+      unitBounds,
+      width: rowWidth,
+      maxHeight: maxUnitHeightInRow,
+    };
+  });
+
+  // Calculate the total height of the grid including padding between rows
+  const totalGridHeightWithPadding =
+    totalGridActualHeight + Math.max(0, rows.length - 1) * padding;
+
+  // Calculate the starting Y position to center the entire grid vertically around centerY
+  let currentY = centerY - totalGridHeightWithPadding / 2;
+
+  // Position atomic units row by row
+  rowProperties.forEach((rowProp) => {
+    const { unitBounds, width: rowWidth, maxHeight: rowMaxHeight } = rowProp;
+
+    // Calculate the starting X for the current row to center it horizontally around centerX
+    let currentX = centerX - rowWidth / 2;
+
+    unitBounds.forEach((unitBound) => {
+      // Calculate the offset needed to position this atomic unit
+      const [originalMinX, originalMinY] = unitBound.bounds;
+      const offsetX = currentX - originalMinX;
+      const offsetY = currentY - originalMinY;
+
+      // Apply the offset to all elements in this atomic unit
+      unitBound.elements.forEach((element) => {
+        res.push(
+          newElementWith(element, {
+            x: element.x + offsetX,
+            y: element.y + offsetY,
+          } as ElementUpdate<TElement>),
+        );
+      });
+
+      // Move X for the next unit in the row
+      currentX += unitBound.width + padding;
+    });
+
+    // Move Y to the starting position for the next row
+    // This accounts for the tallest unit in the current row and the inter-row padding
+    currentY += rowMaxHeight + padding;
+  });
+  return res;
+};