import type { BlockElement } from 'roosterjs-editor-types';
/**
 * This produces a block element from a a node
 * It needs to account for various HTML structure. Examples:
 * 1) <root><div>abc</div></root>
 *   This is most common the case, user passes in a node pointing to abc, and get back a block representing <div>abc</div>
 * 2) <root><p><br></p></root>
 *   Common content for empty block, user passes node pointing to <br>, and get back a block representing <p><br></p>
 * 3) <root>abc</root>
 *   Not common, but does happen. It is still a block in user's view. User passes in abc, and get back a start-end block representing abc
 *   NOTE: abc could be just one node. However, since it is not a html block, it is more appropriate to use start-end block although they point to same node
 * 4) <root><div>abc<br>123</div></root>
 *   A bit tricky, but can happen when user use Ctrl+Enter which simply inserts a <BR> to create a link break. There're two blocks:
 *   block1: 1) abc<br> block2: 123
 * 5) <root><div>abc<div>123</div></div></root>
 *   Nesting div and there is text node in same level as a DIV. Two blocks: 1) abc 2) <div>123</div>
 * 6) <root><div>abc<span>123<br>456</span></div></root>
 *   This is really tricky. Essentially there is a <BR> in middle of a span breaking the span into two blocks;
 *   block1: abc<span>123<br> block2: 456
 * In summary, given any arbitrary node (leaf), to identify the head and tail of the block, following rules need to be followed:
 * 1) to identify the head, it needs to crawl DOM tre left/up till a block node or BR is encountered
 * 2) same for identifying tail
 * 3) should also apply a block ceiling, meaning as it crawls up, it should stop at a block node
 * @param rootNode Root node of the scope, the block element will be inside of this node
 * @param node The node to get BlockElement start from
 */
export default function getBlockElementAtNode(rootNode: Node, node: Node | null): BlockElement | null;