import { exec as execCb } from "node:child_process";
import * as fs from "node:fs/promises";
import * as os from "node:os";
import * as path from "node:path";
import { env } from "node:process";
import { promisify } from "node:util";

const exec = promisify(execCb);

/**
 * @param {string} progName
 * @returns {Promise<boolean>}
 */
async function where(progName) {
  // Reject paths
  if (/[\\]/.test(progName)) return false;
  try {
    await exec(`where "${progName}"`);
  } catch {
    return false;
  }

  return true;
}

/**
 * @param {string} progName
 * @returns {Promise<boolean>}
 */
export async function which(progName) {
  return os.type() === "Windows_NT"
    ? where(progName)
    : Promise.any(
        Array.from(new Set(env.PATH?.split(":"))).map((dir) =>
          fs.access(path.join(dir, progName), fs.constants.X_OK)
        )
      ).then(
        () => true,
        () => false
      );
}