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Packs ECMAScript/CommonJs/AMD modules for the browser. Allows you to split your codebase into multiple bundles, which can be loaded on demand. Supports loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.
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/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/

"use strict";

/** @typedef {import("./Module")} Module */

const MODULE_REFERENCE_REGEXP =
	/^__WEBPACK_MODULE_REFERENCE__(\d+)_([\da-f]+|ns)(_call)?(_directImport)?(?:_asiSafe(\d))?__$/;

const DEFAULT_EXPORT = "__WEBPACK_DEFAULT_EXPORT__";
const NAMESPACE_OBJECT_EXPORT = "__WEBPACK_NAMESPACE_OBJECT__";

/**
 * @typedef {object} ExternalModuleInfo
 * @property {number} index
 * @property {Module} module
 */

/**
 * @typedef {object} ConcatenatedModuleInfo
 * @property {number} index
 * @property {Module} module
 * @property {Map} exportMap mapping from export name to symbol
 * @property {Map} rawExportMap mapping from export name to symbol
 * @property {string=} namespaceExportSymbol
 */

/** @typedef {ConcatenatedModuleInfo | ExternalModuleInfo} ModuleInfo */

/**
 * @typedef {object} ModuleReferenceOptions
 * @property {string[]} ids the properties/exports of the module
 * @property {boolean} call true, when this referenced export is called
 * @property {boolean} directImport true, when this referenced export is directly imported (not via property access)
 * @property {boolean | undefined} asiSafe if the position is ASI safe or unknown
 */

class ConcatenationScope {
	/**
	 * @param {ModuleInfo[] | Map} modulesMap all module info by module
	 * @param {ConcatenatedModuleInfo} currentModule the current module info
	 */
	constructor(modulesMap, currentModule) {
		this._currentModule = currentModule;
		if (Array.isArray(modulesMap)) {
			const map = new Map();
			for (const info of modulesMap) {
				map.set(info.module, info);
			}
			modulesMap = map;
		}
		this._modulesMap = modulesMap;
	}

	/**
	 * @param {Module} module the referenced module
	 * @returns {boolean} true, when it's in the scope
	 */
	isModuleInScope(module) {
		return this._modulesMap.has(module);
	}

	/**
	 *
	 * @param {string} exportName name of the export
	 * @param {string} symbol identifier of the export in source code
	 */
	registerExport(exportName, symbol) {
		if (!this._currentModule.exportMap) {
			this._currentModule.exportMap = new Map();
		}
		if (!this._currentModule.exportMap.has(exportName)) {
			this._currentModule.exportMap.set(exportName, symbol);
		}
	}

	/**
	 *
	 * @param {string} exportName name of the export
	 * @param {string} expression expression to be used
	 */
	registerRawExport(exportName, expression) {
		if (!this._currentModule.rawExportMap) {
			this._currentModule.rawExportMap = new Map();
		}
		if (!this._currentModule.rawExportMap.has(exportName)) {
			this._currentModule.rawExportMap.set(exportName, expression);
		}
	}

	/**
	 * @param {string} symbol identifier of the export in source code
	 */
	registerNamespaceExport(symbol) {
		this._currentModule.namespaceExportSymbol = symbol;
	}

	/**
	 *
	 * @param {Module} module the referenced module
	 * @param {Partial} options options
	 * @returns {string} the reference as identifier
	 */
	createModuleReference(
		module,
		{ ids = undefined, call = false, directImport = false, asiSafe = false }
	) {
		const info = /** @type {ModuleInfo} */ (this._modulesMap.get(module));
		const callFlag = call ? "_call" : "";
		const directImportFlag = directImport ? "_directImport" : "";
		const asiSafeFlag = asiSafe
			? "_asiSafe1"
			: asiSafe === false
				? "_asiSafe0"
				: "";
		const exportData = ids
			? Buffer.from(JSON.stringify(ids), "utf-8").toString("hex")
			: "ns";
		// a "._" is appended to allow "delete ...", which would cause a SyntaxError in strict mode
		return `__WEBPACK_MODULE_REFERENCE__${info.index}_${exportData}${callFlag}${directImportFlag}${asiSafeFlag}__._`;
	}

	/**
	 * @param {string} name the identifier
	 * @returns {boolean} true, when it's an module reference
	 */
	static isModuleReference(name) {
		return MODULE_REFERENCE_REGEXP.test(name);
	}

	/**
	 * @param {string} name the identifier
	 * @returns {ModuleReferenceOptions & { index: number } | null} parsed options and index
	 */
	static matchModuleReference(name) {
		const match = MODULE_REFERENCE_REGEXP.exec(name);
		if (!match) return null;
		const index = +match[1];
		const asiSafe = match[5];
		return {
			index,
			ids:
				match[2] === "ns"
					? []
					: JSON.parse(Buffer.from(match[2], "hex").toString("utf-8")),
			call: !!match[3],
			directImport: !!match[4],
			asiSafe: asiSafe ? asiSafe === "1" : undefined
		};
	}
}

ConcatenationScope.DEFAULT_EXPORT = DEFAULT_EXPORT;
ConcatenationScope.NAMESPACE_OBJECT_EXPORT = NAMESPACE_OBJECT_EXPORT;

module.exports = ConcatenationScope;