import process from 'node:process';
import fs, {constants as fsConstants} from 'node:fs/promises';
import isWsl from 'is-wsl';

export const wslDrivesMountPoint = (() => {
	// Default value for "root" param
	// according to https://docs.microsoft.com/en-us/windows/wsl/wsl-config
	const defaultMountPoint = '/mnt/';

	let mountPoint;

	return async function () {
		if (mountPoint) {
			// Return memoized mount point value
			return mountPoint;
		}

		const configFilePath = '/etc/wsl.conf';

		let isConfigFileExists = false;
		try {
			await fs.access(configFilePath, fsConstants.F_OK);
			isConfigFileExists = true;
		} catch {}

		if (!isConfigFileExists) {
			return defaultMountPoint;
		}

		const configContent = await fs.readFile(configFilePath, {encoding: 'utf8'});
		const configMountPoint = /(?<!#.*)root\s*=\s*(?<mountPoint>.*)/g.exec(configContent);

		if (!configMountPoint) {
			return defaultMountPoint;
		}

		mountPoint = configMountPoint.groups.mountPoint.trim();
		mountPoint = mountPoint.endsWith('/') ? mountPoint : `${mountPoint}/`;

		return mountPoint;
	};
})();

export const powerShellPathFromWsl = async () => {
	const mountPoint = await wslDrivesMountPoint();
	return `${mountPoint}c/Windows/System32/WindowsPowerShell/v1.0/powershell.exe`;
};

export const powerShellPath = async () => {
	if (isWsl) {
		return powerShellPathFromWsl();
	}

	return `${process.env.SYSTEMROOT || process.env.windir || String.raw`C:\Windows`}\\System32\\WindowsPowerShell\\v1.0\\powershell.exe`;
};

export {default as isWsl} from 'is-wsl';