export type EntityList = Record<string, string>;
const rawToEntityEntries = [ ["&", "&"], ["<", "<"], [">", ">"], ['"', """], ["'", "'"],] as const;
const defaultEntityList: EntityList = Object.fromEntries([ ...rawToEntityEntries.map(([raw, entity]) => [entity, raw]), ["'", "'"], [" ", "\xa0"],]);
const rawToEntity = new Map<string, string>(rawToEntityEntries);
const rawRe = new RegExp(`[${[...rawToEntity.keys()].join("")}]`, "g");
export function escape(str: string): string { return str.replaceAll(rawRe, (m) => rawToEntity.get(m)!);}
export type UnescapeOptions = { entityList: EntityList };
const defaultUnescapeOptions: UnescapeOptions = { entityList: defaultEntityList,};
const MAX_CODE_POINT = 0x10ffff;
const RX_DEC_ENTITY = /&#([0-9]+);/g;const RX_HEX_ENTITY = /&#x(\p{AHex}+);/gu;
const entityListRegexCache = new WeakMap<EntityList, RegExp>();
export function unescape( str: string, options: Partial<UnescapeOptions> = {},): string { const { entityList } = { ...defaultUnescapeOptions, ...options };
let entityRe = entityListRegexCache.get(entityList);
if (!entityRe) { entityRe = new RegExp( `(${ Object.keys(entityList) .sort((a, b) => b.length - a.length) .join("|") })`, "g", );
entityListRegexCache.set(entityList, entityRe); }
return str .replaceAll(entityRe, (m) => entityList[m]!) .replaceAll(RX_DEC_ENTITY, (_, dec) => codePointStrToChar(dec, 10)) .replaceAll(RX_HEX_ENTITY, (_, hex) => codePointStrToChar(hex, 16));}
function codePointStrToChar(codePointStr: string, radix: number) { const codePoint = parseInt(codePointStr, radix);
return codePoint > MAX_CODE_POINT ? "�" : String.fromCodePoint(codePoint);}