exstack/dist/router/reg-exp/node.cjs

A utility library designed to simplify and enhance Express.js applications.

//#region src/router/reg-exp/node.ts
const LABEL_REG_EXP_STR = "[^/]+";
const ONLY_WILDCARD_REG_EXP_STR = ".*";
const TAIL_WILDCARD_REG_EXP_STR = "(?:|/.*)";
const PATH_ERROR = Symbol();
const regExpMetaChars = /* @__PURE__ */ new Set(".\\+*[^]$()");
/**
* Sort order:
* 1. literal
* 2. special pattern (e.g. :label{[0-9]+})
* 3. common label pattern (e.g. :label)
* 4. wildcard
*/
const compareKey = (a, b) => {
	if (a.length === 1) return b.length === 1 ? a < b ? -1 : 1 : -1;
	if (b.length === 1) return 1;
	if (a === ONLY_WILDCARD_REG_EXP_STR || a === TAIL_WILDCARD_REG_EXP_STR) return 1;
	else if (b === ONLY_WILDCARD_REG_EXP_STR || b === TAIL_WILDCARD_REG_EXP_STR) return -1;
	if (a === LABEL_REG_EXP_STR) return 1;
	else if (b === LABEL_REG_EXP_STR) return -1;
	return a.length === b.length ? a < b ? -1 : 1 : b.length - a.length;
};
var Node = class Node {
	#index;
	#varIndex;
	#children = Object.create(null);
	insert(tokens, index, paramMap, context, pathErrorCheckOnly) {
		if (tokens.length === 0) {
			if (this.#index !== void 0) throw PATH_ERROR;
			if (pathErrorCheckOnly) return;
			this.#index = index;
			return;
		}
		const [token, ...restTokens] = tokens;
		const pattern = token === "*" ? restTokens.length === 0 ? [
			"",
			"",
			ONLY_WILDCARD_REG_EXP_STR
		] : [
			"",
			"",
			LABEL_REG_EXP_STR
		] : token === "/*" ? [
			"",
			"",
			TAIL_WILDCARD_REG_EXP_STR
		] : token.match(/^\:([^\{\}]+)(?:\{(.+)\})?$/);
		let node;
		if (pattern) {
			const name = pattern[1];
			let regexpStr = pattern[2] || LABEL_REG_EXP_STR;
			if (name && pattern[2]) {
				if (regexpStr === ".*") throw PATH_ERROR;
				regexpStr = regexpStr.replace(/^\((?!\?:)(?=[^)]+\)$)/, "(?:");
				if (/\((?!\?:)/.test(regexpStr)) throw PATH_ERROR;
			}
			node = this.#children[regexpStr];
			if (!node) {
				if (Object.keys(this.#children).some((k) => k !== ONLY_WILDCARD_REG_EXP_STR && k !== TAIL_WILDCARD_REG_EXP_STR)) throw PATH_ERROR;
				if (pathErrorCheckOnly) return;
				node = this.#children[regexpStr] = new Node();
				if (name !== "") node.#varIndex = context.varIndex++;
			}
			if (!pathErrorCheckOnly && name !== "") paramMap.push([name, node.#varIndex]);
		} else {
			node = this.#children[token];
			if (!node) {
				if (Object.keys(this.#children).some((k) => k.length > 1 && k !== ONLY_WILDCARD_REG_EXP_STR && k !== TAIL_WILDCARD_REG_EXP_STR)) throw PATH_ERROR;
				if (pathErrorCheckOnly) return;
				node = this.#children[token] = new Node();
			}
		}
		node.insert(restTokens, index, paramMap, context, pathErrorCheckOnly);
	}
	buildRegExpStr() {
		const strList = Object.keys(this.#children).sort(compareKey).map((k) => {
			const c = this.#children[k];
			return (typeof c.#varIndex === "number" ? `(${k})@${c.#varIndex}` : regExpMetaChars.has(k) ? `\\${k}` : k) + c.buildRegExpStr();
		});
		if (typeof this.#index === "number") strList.unshift(`#${this.#index}`);
		if (strList.length === 0) return "";
		if (strList.length === 1) return strList[0];
		return "(?:" + strList.join("|") + ")";
	}
};
var Trie = class {
	#context = { varIndex: 0 };
	#root = new Node();
	insert(path, index, pathErrorCheckOnly) {
		const paramAssoc = [];
		const groups = [];
		for (let i = 0;;) {
			let replaced = false;
			path = path.replace(/\{[^}]+\}/g, (m) => {
				const mark = `@\\${i}`;
				groups[i] = [mark, m];
				i++;
				replaced = true;
				return mark;
			});
			if (!replaced) break;
		}
		/**
		*  - pattern (:label, :label{0-9]+}, ...)
		*  - /* wildcard
		*  - character
		*/
		const tokens = path.match(/(?::[^\/]+)|(?:\/\*$)|./g) || [];
		for (let i = groups.length - 1; i >= 0; i--) {
			const [mark] = groups[i];
			for (let j = tokens.length - 1; j >= 0; j--) if (tokens[j].indexOf(mark) !== -1) {
				tokens[j] = tokens[j].replace(mark, groups[i][1]);
				break;
			}
		}
		this.#root.insert(tokens, index, paramAssoc, this.#context, pathErrorCheckOnly);
		return paramAssoc;
	}
	buildRegExp() {
		let regexp = this.#root.buildRegExpStr();
		if (regexp === "") return [
			/^$/,
			[],
			[]
		];
		let captureIndex = 0;
		const indexReplacementMap = [];
		const paramReplacementMap = [];
		regexp = regexp.replace(/#(\d+)|@(\d+)|\.\*\$/g, (_, handlerIndex, paramIndex) => {
			if (handlerIndex !== void 0) {
				indexReplacementMap[++captureIndex] = Number(handlerIndex);
				return "$()";
			}
			if (paramIndex !== void 0) {
				paramReplacementMap[Number(paramIndex)] = ++captureIndex;
				return "";
			}
			return "";
		});
		return [
			/* @__PURE__ */ new RegExp(`^${regexp}`),
			indexReplacementMap,
			paramReplacementMap
		];
	}
};

//#endregion
exports.PATH_ERROR = PATH_ERROR;
exports.Trie = Trie;