feat: support creating containers, linear elements, text containers, labelled arrows and arrow bindings programatically (#6546)

* feat: support creating text containers programatically

* fix

* fix

* fix

* fix

* update api to use label

* fix api and support individual shapes and text element

* update test case in package example

* support creating arrows and line

* support labelled arrows

* add in package example

* fix alignment

* better types

* fix

* keep element as is unless we support prog api

* fix tests

* fix lint

* ignore

* support arrow bindings via start and end in api

* fix lint

* fix coords

* support id as well for elements

* preserve bindings if present and fix testcases

* preserve bindings for labelled arrows

* support ids, clean up code and move the api related stuff to transform.ts

* allow multiple arrows to bind to single element

* fix singular elements

* fix single text element, unique id and tests

* fix lint

* fix

* support binding arrow to text element

* fix creation of regular text

* use same stroke color as parent for text containers and height 0 for linear element by default

* fix types

* fix

* remove more ts ignore

* remove ts ignore

* remove

* Add coverage script

* Add tests

* fix tests

* make type optional when id present

* remove type when id provided in tests

* Add more tests

* tweak

* let host call convertToExcalidrawElements when using programmatic API

* remove convertToExcalidrawElements call from restore

* lint

* update snaps

* Add new type excalidraw-api/clipboard for programmatic api

* cleanup

* rename tweak

* tweak

* make image attributes optional and better ts check

* support image via programmatic API

* fix lint

* more types

* make fileId mandatory for image and export convertToExcalidrawElements

* fix

* small tweaks

* update snaps

* fix

* use Object.assign instead of mutateElement

* lint

* preserve z-index by pushing all elements first and then add bindings

* instantiate instead of closure for storing elements

* use element API to create regular text, diamond, ellipse and rectangle

* fix snaps

* udpdate api

* ts fixes

* make `convertToExcalidrawElements` more typesafe

* update snaps

* refactor the approach so that order of elements doesn't matter

* Revert "update snaps"

This reverts commit 621dfadccfea975a1f77223f506dce9d260f91fd.

* review fixes

* rename ExcalidrawProgrammaticElement -> ExcalidrawELementSkeleton

* Add tests

* give preference to first element when duplicate ids found

* use console.error

---------

Co-authored-by: dwelle <luzar.david@gmail.com>

src/element/binding.ts

@@ -190,7 +190,7 @@ export const maybeBindLinearElement = (
   }
 };
 
-const bindLinearElement = (
+export const bindLinearElement = (
   linearElement: NonDeleted<ExcalidrawLinearElement>,
   hoveredElement: ExcalidrawBindableElement,
   startOrEnd: "start" | "end",

src/element/newElement.ts

@@ -46,7 +46,7 @@ import {
 } from "../constants";
 import { MarkOptional, Merge, Mutable } from "../utility-types";
 
-type ElementConstructorOpts = MarkOptional<
+export type ElementConstructorOpts = MarkOptional<
   Omit<ExcalidrawGenericElement, "id" | "type" | "isDeleted" | "updated">,
   | "width"
   | "height"
@@ -187,7 +187,7 @@ export const newTextElement = (
     fontFamily?: FontFamilyValues;
     textAlign?: TextAlign;
     verticalAlign?: VerticalAlign;
-    containerId?: ExcalidrawTextContainer["id"];
+    containerId?: ExcalidrawTextContainer["id"] | null;
     lineHeight?: ExcalidrawTextElement["lineHeight"];
     strokeWidth?: ExcalidrawTextElement["strokeWidth"];
   } & ElementConstructorOpts,
@@ -361,8 +361,8 @@ export const newFreeDrawElement = (
 export const newLinearElement = (
   opts: {
     type: ExcalidrawLinearElement["type"];
-    startArrowhead: Arrowhead | null;
-    endArrowhead: Arrowhead | null;
+    startArrowhead?: Arrowhead | null;
+    endArrowhead?: Arrowhead | null;
     points?: ExcalidrawLinearElement["points"];
   } & ElementConstructorOpts,
 ): NonDeleted<ExcalidrawLinearElement> => {
@@ -372,8 +372,8 @@ export const newLinearElement = (
     lastCommittedPoint: null,
     startBinding: null,
     endBinding: null,
-    startArrowhead: opts.startArrowhead,
-    endArrowhead: opts.endArrowhead,
+    startArrowhead: opts.startArrowhead || null,
+    endArrowhead: opts.endArrowhead || null,
   };
 };
 
@@ -477,7 +477,7 @@ export const deepCopyElement = <T extends ExcalidrawElement>(
  * utility wrapper to generate new id. In test env it reuses the old + postfix
  * for test assertions.
  */
-const regenerateId = (
+export const regenerateId = (
   /** supply null if no previous id exists */
   previousId: string | null,
 ) => {

src/element/textElement.ts

@@ -89,16 +89,23 @@ export const redrawTextBoundingBox = (
       container,
       textElement as ExcalidrawTextElementWithContainer,
     );
+    const maxContainerWidth = getBoundTextMaxWidth(container);
 
-    let nextHeight = container.height;
     if (metrics.height > maxContainerHeight) {
-      nextHeight = computeContainerDimensionForBoundText(
+      const nextHeight = computeContainerDimensionForBoundText(
         metrics.height,
         container.type,
       );
       mutateElement(container, { height: nextHeight });
       updateOriginalContainerCache(container.id, nextHeight);
     }
+    if (metrics.width > maxContainerWidth) {
+      const nextWidth = computeContainerDimensionForBoundText(
+        metrics.width,
+        container.type,
+      );
+      mutateElement(container, { width: nextWidth });
+    }
     const updatedTextElement = {
       ...textElement,
       ...boundTextUpdates,
@@ -859,8 +866,9 @@ const VALID_CONTAINER_TYPES = new Set([
   "arrow",
 ]);
 
-export const isValidTextContainer = (element: ExcalidrawElement) =>
-  VALID_CONTAINER_TYPES.has(element.type);
+export const isValidTextContainer = (element: {
+  type: ExcalidrawElement["type"];
+}) => VALID_CONTAINER_TYPES.has(element.type);
 
 export const computeContainerDimensionForBoundText = (
   dimension: number,