anki/ts/editor/helpers.ts
Damien Elmes 41c4be2f54 Introduce editable-container
Contains the shadow root, and references to the styles.
Is ignorant of Editable.
Is necessary, so our we editable.scss does not need to contain
information about Codable, ImageHandle or all those other things which
have nothing to do with Editable
2021-09-06 21:15:36 +10:00

104 lines
2.6 KiB
TypeScript

// Copyright: Ankitects Pty Ltd and contributors
// License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
/* eslint
@typescript-eslint/no-non-null-assertion: "off",
*/
import type { EditingArea } from "./editing-area";
export function getCurrentField(): EditingArea | null {
return document.activeElement?.closest(".field") ?? null;
}
export function nodeIsElement(node: Node): node is Element {
return node.nodeType === Node.ELEMENT_NODE;
}
// https://developer.mozilla.org/en-US/docs/Web/HTML/Block-level_elements
const BLOCK_TAGS = [
"ADDRESS",
"ARTICLE",
"ASIDE",
"BLOCKQUOTE",
"DETAILS",
"DIALOG",
"DD",
"DIV",
"DL",
"DT",
"FIELDSET",
"FIGCAPTION",
"FIGURE",
"FOOTER",
"FORM",
"H1",
"H2",
"H3",
"H4",
"H5",
"H6",
"HEADER",
"HGROUP",
"HR",
"LI",
"MAIN",
"NAV",
"OL",
"P",
"PRE",
"SECTION",
"TABLE",
"UL",
];
export function elementIsBlock(element: Element): boolean {
return BLOCK_TAGS.includes(element.tagName);
}
export function caretToEnd(node: Node): void {
const range = document.createRange();
range.selectNodeContents(node);
range.collapse(false);
const selection = (node.getRootNode() as Document | ShadowRoot).getSelection()!;
selection.removeAllRanges();
selection.addRange(range);
}
const getAnchorParent =
<T extends Element>(predicate: (element: Element) => element is T) =>
(currentField: DocumentOrShadowRoot): T | null => {
const anchor = currentField.getSelection()?.anchorNode;
if (!anchor) {
return null;
}
let anchorParent: T | null = null;
let element = nodeIsElement(anchor) ? anchor : anchor.parentElement;
while (element) {
anchorParent = anchorParent || (predicate(element) ? element : null);
element = element.parentElement;
}
return anchorParent;
};
const isListItem = (element: Element): element is HTMLLIElement =>
window.getComputedStyle(element).display === "list-item";
const isParagraph = (element: Element): element is HTMLParamElement =>
element.tagName === "P";
const isBlockElement = (
element: Element
): element is HTMLLIElement & HTMLParamElement =>
isListItem(element) || isParagraph(element);
export const getListItem = getAnchorParent(isListItem);
export const getParagraph = getAnchorParent(isParagraph);
export const getBlockElement = getAnchorParent(isBlockElement);
export function appendInParentheses(text: string, appendix: string): string {
return `${text} (${appendix})`;
}