[Editor] Don't use the editor parent which can be null.

An annotation editor layer can be destroyed when it's invisible, hence some
annotations can have a null parent but when printing/saving or when changing
font size, color, ... of all added annotations (when selected with ctrl+a) we
still need to have some parent properties especially the page dimensions, global
scale factor and global rotation angle.
This patch aims to remove all the references to the parent in the editor instances
except in some cases where an editor should obviously have one.
It fixes #15780.

src/display/editor/ink.js

@@ -165,7 +165,7 @@ class InkEditor extends AnnotationEditor {
    */
   #updateThickness(thickness) {
     const savedThickness = this.thickness;
-    this.parent.addCommands({
+    this.addCommands({
       cmd: () => {
         this.thickness = thickness;
         this.#fitToContent();
@@ -187,7 +187,7 @@ class InkEditor extends AnnotationEditor {
    */
   #updateColor(color) {
     const savedColor = this.color;
-    this.parent.addCommands({
+    this.addCommands({
       cmd: () => {
         this.color = color;
         this.#redraw();
@@ -210,7 +210,7 @@ class InkEditor extends AnnotationEditor {
   #updateOpacity(opacity) {
     opacity /= 100;
     const savedOpacity = this.opacity;
-    this.parent.addCommands({
+    this.addCommands({
       cmd: () => {
         this.opacity = opacity;
         this.#redraw();
@@ -268,6 +268,27 @@ class InkEditor extends AnnotationEditor {
     super.remove();
   }
 
+  setParent(parent) {
+    if (!this.parent && parent) {
+      // We've a parent hence the rescale will be handled thanks to the
+      // ResizeObserver.
+      this._uiManager.removeShouldRescale(this);
+    } else if (this.parent && parent === null) {
+      // The editor is removed from the DOM, hence we handle the rescale thanks
+      // to the onScaleChanging callback.
+      // This way, it'll be saved/printed correctly.
+      this._uiManager.addShouldRescale(this);
+    }
+    super.setParent(parent);
+  }
+
+  onScaleChanging() {
+    const [parentWidth, parentHeight] = this.parentDimensions;
+    const width = this.width * parentWidth;
+    const height = this.height * parentHeight;
+    this.setDimensions(width, height);
+  }
+
   /** @inheritdoc */
   enableEditMode() {
     if (this.#disableEditing || this.canvas === null) {
@@ -311,14 +332,17 @@ class InkEditor extends AnnotationEditor {
   }
 
   #getInitialBBox() {
-    const { width, height, rotation } = this.parent.viewport;
-    switch (rotation) {
+    const {
+      parentRotation,
+      parentDimensions: [width, height],
+    } = this;
+    switch (parentRotation) {
       case 90:
-        return [0, width, width, height];
+        return [0, height, height, width];
       case 180:
         return [width, height, width, height];
       case 270:
-        return [height, 0, width, height];
+        return [width, 0, height, width];
       default:
         return [0, 0, width, height];
     }
@@ -328,12 +352,12 @@ class InkEditor extends AnnotationEditor {
    * Set line styles.
    */
   #setStroke() {
-    this.ctx.lineWidth =
-      (this.thickness * this.parent.scaleFactor) / this.scaleFactor;
-    this.ctx.lineCap = "round";
-    this.ctx.lineJoin = "round";
-    this.ctx.miterLimit = 10;
-    this.ctx.strokeStyle = `${this.color}${opacityToHex(this.opacity)}`;
+    const { ctx, color, opacity, thickness, parentScale, scaleFactor } = this;
+    ctx.lineWidth = (thickness * parentScale) / scaleFactor;
+    ctx.lineCap = "round";
+    ctx.lineJoin = "round";
+    ctx.miterLimit = 10;
+    ctx.strokeStyle = `${color}${opacityToHex(opacity)}`;
   }
 
   /**
@@ -445,7 +469,7 @@ class InkEditor extends AnnotationEditor {
       }
     };
 
-    this.parent.addCommands({ cmd, undo, mustExec: true });
+    this.addCommands({ cmd, undo, mustExec: true });
   }
 
   /**
@@ -493,9 +517,11 @@ class InkEditor extends AnnotationEditor {
     // When commiting, the position of this editor is changed, hence we must
     // move it to the right position in the DOM.
     this.parent.moveEditorInDOM(this);
-    // After the div has been moved in the DOM, the focus may have been stolen
-    // by document.body, hence we just keep it here.
-    this.div.focus();
+    if (this.pageIndex === this._uiManager.currentPageIndex) {
+      // After the div has been moved in the DOM, the focus may have been stolen
+      // by document.body, hence we just keep it here.
+      this.div.focus();
+    }
   }
 
   /** @inheritdoc */
@@ -581,7 +607,7 @@ class InkEditor extends AnnotationEditor {
       this.#boundCanvasPointermove
     );
 
-    this.parent.addToAnnotationStorage(this);
+    this.addToAnnotationStorage();
   }
 
   /**
@@ -649,7 +675,7 @@ class InkEditor extends AnnotationEditor {
 
     if (this.width) {
       // This editor was created in using copy (ctrl+c).
-      const [parentWidth, parentHeight] = this.parent.viewportBaseDimensions;
+      const [parentWidth, parentHeight] = this.parentDimensions;
       this.setAt(
         baseX * parentWidth,
         baseY * parentHeight,
@@ -676,7 +702,7 @@ class InkEditor extends AnnotationEditor {
     if (!this.#isCanvasInitialized) {
       return;
     }
-    const [parentWidth, parentHeight] = this.parent.viewportBaseDimensions;
+    const [parentWidth, parentHeight] = this.parentDimensions;
     this.canvas.width = Math.ceil(this.width * parentWidth);
     this.canvas.height = Math.ceil(this.height * parentHeight);
     this.#updateTransform();
@@ -712,7 +738,7 @@ class InkEditor extends AnnotationEditor {
       this.setDims(width, height);
     }
 
-    const [parentWidth, parentHeight] = this.parent.viewportBaseDimensions;
+    const [parentWidth, parentHeight] = this.parentDimensions;
     this.width = width / parentWidth;
     this.height = height / parentHeight;
 
@@ -940,7 +966,7 @@ class InkEditor extends AnnotationEditor {
    */
   #getPadding() {
     return this.#disableEditing
-      ? Math.ceil(this.thickness * this.parent.scaleFactor)
+      ? Math.ceil(this.thickness * this.parentScale)
       : 0;
   }
 
@@ -967,7 +993,7 @@ class InkEditor extends AnnotationEditor {
     const width = Math.ceil(padding + this.#baseWidth * this.scaleFactor);
     const height = Math.ceil(padding + this.#baseHeight * this.scaleFactor);
 
-    const [parentWidth, parentHeight] = this.parent.viewportBaseDimensions;
+    const [parentWidth, parentHeight] = this.parentDimensions;
     this.width = width / parentWidth;
     this.height = height / parentHeight;
 
@@ -1005,17 +1031,17 @@ class InkEditor extends AnnotationEditor {
   }
 
   /** @inheritdoc */
-  static deserialize(data, parent) {
-    const editor = super.deserialize(data, parent);
+  static deserialize(data, parent, uiManager) {
+    const editor = super.deserialize(data, parent, uiManager);
 
     editor.thickness = data.thickness;
     editor.color = Util.makeHexColor(...data.color);
     editor.opacity = data.opacity;
 
-    const [pageWidth, pageHeight] = parent.pageDimensions;
+    const [pageWidth, pageHeight] = editor.pageDimensions;
     const width = editor.width * pageWidth;
     const height = editor.height * pageHeight;
-    const scaleFactor = parent.scaleFactor;
+    const scaleFactor = editor.parentScale;
     const padding = data.thickness / 2;
 
     editor.#aspectRatio = width / height;
@@ -1058,10 +1084,6 @@ class InkEditor extends AnnotationEditor {
 
   /** @inheritdoc */
   serialize() {
-    if (this._serialized !== undefined) {
-      return this._serialized;
-    }
-
     if (this.isEmpty()) {
       return null;
     }
@@ -1078,12 +1100,12 @@ class InkEditor extends AnnotationEditor {
       thickness: this.thickness,
       opacity: this.opacity,
       paths: this.#serializePaths(
-        this.scaleFactor / this.parent.scaleFactor,
+        this.scaleFactor / this.parentScale,
         this.translationX,
         this.translationY,
         height
       ),
-      pageIndex: this.parent.pageIndex,
+      pageIndex: this.pageIndex,
       rect,
       rotation: this.rotation,
     };