/**
* @license Copyright (c) 2003-2026, CKSource Holding sp. z o.o. All rights reserved.
* For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-licensing-options
*/
/**
* @module engine/view/attributeelement
*/
import { ViewElement, type ViewElementAttributes } from "./element.js";
import { type ViewDocument } from "./document.js";
import { type ViewNode } from "./node.js";
/**
* Attribute elements are used to represent formatting elements in the view (think – `<b>`, `<span style="font-size: 2em">`, etc.).
* Most often they are created when downcasting model text attributes.
*
* Editing engine does not define a fixed HTML DTD. This is why a feature developer needs to choose between various
* types (container element, {@link module:engine/view/attributeelement~ViewAttributeElement attribute element},
* {@link module:engine/view/emptyelement~ViewEmptyElement empty element}, etc) when developing a feature.
*
* To create a new attribute element instance use the
* {@link module:engine/view/downcastwriter~ViewDowncastWriter#createAttributeElement `ViewDowncastWriter#createAttributeElement()`} method.
*/
export declare class ViewAttributeElement extends ViewElement {
	static readonly DEFAULT_PRIORITY: number;
	/**
	* Element priority. Decides in what order elements are wrapped by {@link module:engine/view/downcastwriter~ViewDowncastWriter}.
	*
	* @internal
	* @readonly
	*/
	_priority: number;
	/**
	* Element identifier. If set, it is used by {@link module:engine/view/element~ViewElement#isSimilar},
	* and then two elements are considered similar if, and only if they have the same `_id`.
	*
	* @internal
	* @readonly
	*/
	_id: string | number | null;
	/**
	* Keeps all the attribute elements that have the same {@link module:engine/view/attributeelement~ViewAttributeElement#id ids}
	* and still exist in the view tree.
	*
	* This property is managed by {@link module:engine/view/downcastwriter~ViewDowncastWriter}.
	*/
	private readonly _clonesGroup;
	/**
	* Creates an attribute element.
	*
	* @see module:engine/view/downcastwriter~ViewDowncastWriter#createAttributeElement
	* @see module:engine/view/element~ViewElement
	* @protected
	* @param document The document instance to which this element belongs.
	* @param name Node name.
	* @param attrs Collection of attributes.
	* @param children A list of nodes to be inserted into created element.
	*/
	constructor(document: ViewDocument, name: string, attrs?: ViewElementAttributes, children?: ViewNode | Iterable<ViewNode>);
	/**
	* Element priority. Decides in what order elements are wrapped by {@link module:engine/view/downcastwriter~ViewDowncastWriter}.
	*/
	get priority(): number;
	/**
	* Element identifier. If set, it is used by {@link module:engine/view/element~ViewElement#isSimilar},
	* and then two elements are considered similar if, and only if they have the same `id`.
	*/
	get id(): string | number | null;
	/**
	* Returns all {@link module:engine/view/attributeelement~ViewAttributeElement attribute elements} that has the
	* same {@link module:engine/view/attributeelement~ViewAttributeElement#id id} and are in the view tree (were not removed).
	*
	* Note: If this element has been removed from the tree, returned set will not include it.
	*
	* Throws {@link module:utils/ckeditorerror~CKEditorError attribute-element-get-elements-with-same-id-no-id}
	* if this element has no `id`.
	*
	* @returns Set containing all the attribute elements
	* with the same `id` that were added and not removed from the view tree.
	*/
	getElementsWithSameId(): Set<ViewAttributeElement>;
	/**
	* Checks if this element is similar to other element.
	*
	* If none of elements has set {@link module:engine/view/attributeelement~ViewAttributeElement#id}, then both elements
	* should have the same name, attributes and priority to be considered as similar. Two similar elements can contain
	* different set of children nodes.
	*
	* If at least one element has {@link module:engine/view/attributeelement~ViewAttributeElement#id} set, then both
	* elements have to have the same {@link module:engine/view/attributeelement~ViewAttributeElement#id} value to be
	* considered similar.
	*
	* Similarity is important for {@link module:engine/view/downcastwriter~ViewDowncastWriter}. For example:
	*
	* * two following similar elements can be merged together into one, longer element,
	* * {@link module:engine/view/downcastwriter~ViewDowncastWriter#unwrap} checks similarity of passed element and processed element to
	* decide whether processed element should be unwrapped,
	* * etc.
	*/
	override isSimilar(otherElement: ViewElement): boolean;
	/**
	* Converts `ViewAttributeElement` instance to plain object and returns it.
	*
	* @returns `ViewAttributeElement` instance converted to plain object.
	*/
	override toJSON(): unknown;
	/**
	* Clones provided element with priority.
	*
	* @internal
	* @param deep If set to `true` clones element and all its children recursively. When set to `false`,
	* element will be cloned without any children.
	* @returns Clone of this element.
	*/
	override _clone(deep?: boolean): this;
	/**
	* Used by {@link module:engine/view/element~ViewElement#_mergeAttributesFrom} to verify if the given element can be merged without
	* conflicts into this element.
	*
	* @internal
	*/
	override _canMergeAttributesFrom(otherElement: ViewAttributeElement): boolean;
	/**
	* Used by {@link module:engine/view/element~ViewElement#_subtractAttributesOf} to verify if the given element attributes
	* can be fully subtracted from this element.
	*
	* @internal
	*/
	override _canSubtractAttributesOf(otherElement: ViewAttributeElement): boolean;
}