/**
 * @fileoverview Common helpers for naming of plugins, formatters and configs
 */

"use strict";

const NAMESPACE_REGEX = /^@.*\//u;

/**
 * Brings package name to correct format based on prefix
 * @param {string} name The name of the package.
 * @param {string} prefix Can be either "eslint-plugin", "eslint-config" or "eslint-formatter"
 * @returns {string} Normalized name of the package
 * @private
 */
function normalizePackageName(name, prefix) {
	let normalizedName = name;

	/**
	 * On Windows, name can come in with Windows slashes instead of Unix slashes.
	 * Normalize to Unix first to avoid errors later on.
	 * https://github.com/eslint/eslint/issues/5644
	 */
	if (normalizedName.includes("\\")) {
		normalizedName = normalizedName.replace(/\\/gu, "/");
	}

	if (normalizedName.charAt(0) === "@") {
		/**
		 * it's a scoped package
		 * package name is the prefix, or just a username
		 */
		const scopedPackageShortcutRegex = new RegExp(
				`^(@[^/]+)(?:/(?:${prefix})?)?$`,
				"u",
			),
			scopedPackageNameRegex = new RegExp(`^${prefix}(-|$)`, "u");

		if (scopedPackageShortcutRegex.test(normalizedName)) {
			normalizedName = normalizedName.replace(
				scopedPackageShortcutRegex,
				`$1/${prefix}`,
			);
		} else if (!scopedPackageNameRegex.test(normalizedName.split("/")[1])) {
			/*
			 * for scoped packages, insert the prefix after the first / unless
			 * the path is already @scope/eslint or @scope/eslint-xxx-yyy
			 */
			normalizedName = normalizedName.replace(
				/^@([^/]+)\/(.*)$/u,
				`@$1/${prefix}-$2`,
			);
		}
	} else if (!normalizedName.startsWith(`${prefix}-`)) {
		normalizedName = `${prefix}-${normalizedName}`;
	}

	return normalizedName;
}

/**
 * Removes the prefix from a fullname.
 * @param {string} fullname The term which may have the prefix.
 * @param {string} prefix The prefix to remove.
 * @returns {string} The term without prefix.
 */
function getShorthandName(fullname, prefix) {
	if (fullname[0] === "@") {
		let matchResult = new RegExp(`^(@[^/]+)/${prefix}$`, "u").exec(
			fullname,
		);

		if (matchResult) {
			return matchResult[1];
		}

		matchResult = new RegExp(`^(@[^/]+)/${prefix}-(.+)$`, "u").exec(
			fullname,
		);
		if (matchResult) {
			return `${matchResult[1]}/${matchResult[2]}`;
		}
	} else if (fullname.startsWith(`${prefix}-`)) {
		return fullname.slice(prefix.length + 1);
	}

	return fullname;
}

/**
 * Gets the scope (namespace) of a term.
 * @param {string} term The term which may have the namespace.
 * @returns {string} The namespace of the term if it has one.
 */
function getNamespaceFromTerm(term) {
	const match = term.match(NAMESPACE_REGEX);

	return match ? match[0] : "";
}

//------------------------------------------------------------------------------
// Public Interface
//------------------------------------------------------------------------------

module.exports = {
	normalizePackageName,
	getShorthandName,
	getNamespaceFromTerm,
};
