const process = require('node:process')
const nodeOs = require('node:os')
const fs = require('node:fs')

function isMusl (file) {
  return file.includes('libc.musl-') || file.includes('ld-musl-')
}

function os () {
  return process.platform
}

function cpu () {
  return process.arch
}

const LDD_PATH = '/usr/bin/ldd'
function getFamilyFromFilesystem () {
  try {
    const content = fs.readFileSync(LDD_PATH, 'utf-8')
    if (content.includes('musl')) {
      return 'musl'
    }
    if (content.includes('GNU C Library')) {
      return 'glibc'
    }
    return null
  } catch {
    return undefined
  }
}

function getFamilyFromReport () {
  const originalExclude = process.report.excludeNetwork
  process.report.excludeNetwork = true
  const report = process.report.getReport()
  process.report.excludeNetwork = originalExclude
  if (report.header?.glibcVersionRuntime) {
    family = 'glibc'
  } else if (Array.isArray(report.sharedObjects) && report.sharedObjects.some(isMusl)) {
    family = 'musl'
  } else {
    family = null
  }
  return family
}

let family
function libc (osName) {
  if (osName !== 'linux') {
    return undefined
  }
  if (family === undefined) {
    family = getFamilyFromFilesystem()
    if (family === undefined) {
      family = getFamilyFromReport()
    }
  }
  return family
}

function devEngines (env = {}) {
  const osName = env.os || os()
  return {
    cpu: {
      name: env.cpu || cpu(),
    },
    libc: {
      name: env.libc || libc(osName),
    },
    os: {
      name: osName,
      version: env.osVersion || nodeOs.release(),
    },
    packageManager: {
      name: 'npm',
      version: env.npmVersion,
    },
    runtime: {
      name: 'node',
      version: env.nodeVersion || process.version,
    },
  }
}

module.exports = {
  cpu,
  libc,
  os,
  devEngines,
}