#!/usr/bin/env node
/**
 * Build peardata-server as a Bare standalone binary (Linux hosts).
 *
 * Flow (Holepunch bare-build + bare-node-runtime):
 * 1. bare-pack the entry with global imports (package.json + bare-node-runtime)
 * 2. Embed the bundle into a bare-runtime prebuild via bare-build platform hooks
 *
 * Usage:
 *   node scripts/bare-standalone.cjs --product server --host linux-x64
 *   node scripts/bare-standalone.cjs --product server --host all
 *
 * Output:
 *   out/peardata-server-<host>/peardata-server
 */
'use strict'

const path = require('path')
const fs = require('fs')
const { pathToFileURL } = require('url')
const pack = require('bare-pack')
const { readModule, listPrefix } = require('bare-pack/fs')
const traverse = require('bare-module-traverse')
const id = require('bare-bundle-id')

const root = path.resolve(__dirname, '..')
const pkg = require(path.join(root, 'package.json'))
const { SERVER_LINUX } = require('./hosts.cjs')

function parseArgs(argv) {
  const out = {
    product: 'server',
    hosts: [],
    outRoot: path.join(root, 'out'),
  }
  for (let i = 0; i < argv.length; i++) {
    const a = argv[i]
    if (a === '--product') out.product = argv[++i]
    else if (a === '--host') {
      const h = argv[++i]
      if (h === 'all') out.hosts.push(...SERVER_LINUX)
      else out.hosts.push(h)
    } else if (a === '--out') out.outRoot = path.resolve(argv[++i])
    else if (a === '--help' || a === '-h') out.help = true
  }
  if (!out.hosts.length) {
    const thisHost = `${process.platform}-${process.arch}`
    out.hosts.push(SERVER_LINUX.includes(thisHost) ? thisHost : 'linux-x64')
  }
  return out
}

/**
 * Global imports map for bare-pack.
 */
function buildImportsMap() {
  let bnr = {}
  try {
    bnr = require('bare-node-runtime/imports')
  } catch {
    console.warn(
      '[bare-standalone] bare-node-runtime/imports not found — relying on package.json imports'
    )
  }
  return { ...bnr, ...(pkg.imports || {}) }
}

function platformForHost(host) {
  const bareBuildRoot = path.dirname(require.resolve('bare-build/package'))
  const load = (name) => require(path.join(bareBuildRoot, 'lib', 'platform', name))
  switch (host) {
    case 'linux-arm64':
    case 'linux-x64':
      return load('linux')
    default:
      throw new Error(
        `peardata-server only builds Linux hosts (got '${host}'). ` +
          `Allowed: ${SERVER_LINUX.join(', ')}`
      )
  }
}

/**
 * @param {string} host
 * @param {string} outRoot
 */
async function buildOne(host, outRoot) {
  if (!SERVER_LINUX.includes(host)) {
    throw new Error(
      `Refusing non-Linux server host '${host}'. Allowed: ${SERVER_LINUX.join(', ')}`
    )
  }

  // Ensure native helpers are compiled + base64-embedded into the JS bundle
  console.log('[bare-standalone] building/embedding native helpers…')
  const { spawnSync } = require('child_process')
  const nh = spawnSync(process.execPath, [path.join(root, 'scripts', 'build-native-helpers.cjs')], {
    cwd: root,
    stdio: 'inherit',
    env: process.env,
  })
  if (nh.status !== 0) {
    console.warn('[bare-standalone] native helper build failed (JS fallback still works)')
  }

  const name = 'peardata-server'
  const outDir = path.join(outRoot, `${name}-${host}`)
  fs.rmSync(outDir, { recursive: true, force: true })
  fs.mkdirSync(outDir, { recursive: true })

  const entryPath = path.join(root, 'bin', 'peardata-server.mjs')
  if (!fs.existsSync(entryPath)) throw new Error(`Missing entry ${entryPath}`)

  const imports = buildImportsMap()
  console.log(`[bare-standalone] packing ${name} for ${host}…`)

  let entry = await pack(
    pathToFileURL(entryPath),
    {
      hosts: [host],
      linked: false,
      resolve: traverse.resolve.bare,
      imports,
    },
    readModule,
    listPrefix
  )

  const baseURL = pathToFileURL(root + path.sep)
  entry = entry.unmount(baseURL)
  entry.id = id(entry).toString('hex')

  const platform = platformForHost(host)
  const opts = {
    name,
    version: pkg.version || '0.0.0',
    description: pkg.description || 'peardata server',
    author: pkg.author || '',
    identifier: 'com.peardata.server',
    hosts: [host],
    out: outDir,
    standalone: true,
    package: false,
    base: root,
  }

  console.log(`[bare-standalone] embedding bare-runtime for ${host}…`)
  for await (const resource of platform(root, entry, null, opts)) {
    if (resource && resource.path) {
      console.log(`[bare-standalone] resource ${resource.path}`)
    }
  }

  const binName = name
  let binary = path.join(outDir, binName)
  if (!fs.existsSync(binary)) {
    const found = walkFind(outDir, (f) => {
      const base = path.basename(f)
      return base === name || base === 'peardata-server'
    })
    if (found) binary = found
  }

  if (fs.existsSync(binary)) {
    try {
      fs.chmodSync(binary, 0o755)
    } catch {
      // ignore
    }
    const flat = path.join(outDir, path.basename(binary))
    if (path.resolve(binary) !== path.resolve(flat)) {
      fs.copyFileSync(binary, flat)
      binary = flat
    }
    // Also ship raw helper next to binary for ops that prefer an external file
    const pre = path.join(root, 'native', 'prebuilds', `peardata-ebpf-${host}`)
    const preAlt = path.join(root, 'native', 'prebuilds', 'peardata-ebpf')
    const helperSrc = fs.existsSync(pre) ? pre : fs.existsSync(preAlt) ? preAlt : null
    if (helperSrc) {
      const helperDest = path.join(outDir, 'peardata-ebpf')
      fs.copyFileSync(helperSrc, helperDest)
      try {
        fs.chmodSync(helperDest, 0o755)
      } catch {
        // ignore
      }
      console.log(`[bare-standalone] shipped helper ${helperDest}`)
    }
    console.log(`[bare-standalone] wrote ${binary}`)
  } else {
    console.warn(`[bare-standalone] WARN: expected binary not found under ${outDir}`)
    console.warn(
      '  contents:',
      fs.readdirSync(outDir, { recursive: true }).slice(0, 30).join(', ')
    )
  }

  fs.writeFileSync(
    path.join(outDir, 'build-info.json'),
    JSON.stringify(
      {
        product: 'server',
        host,
        name,
        version: pkg.version,
        builtAt: new Date().toISOString(),
        entry: 'bin/peardata-server.mjs',
        bundleId: entry.id,
      },
      null,
      2
    ) + '\n'
  )

  return outDir
}

function walkFind(dir, pred) {
  const stack = [dir]
  while (stack.length) {
    const d = stack.pop()
    let entries
    try {
      entries = fs.readdirSync(d, { withFileTypes: true })
    } catch {
      continue
    }
    for (const ent of entries) {
      const p = path.join(d, ent.name)
      if (ent.isDirectory()) stack.push(p)
      else if (pred(p)) return p
    }
  }
  return null
}

async function main() {
  const opts = parseArgs(process.argv.slice(2))
  if (opts.help) {
    console.log(`Usage: node scripts/bare-standalone.cjs [--product server] [--host <host>|all] [--out dir]
Server hosts (Linux only): ${SERVER_LINUX.join(', ')}`)
    process.exit(0)
  }

  if (opts.product !== 'server') {
    throw new Error(
      `bare-standalone only builds product=server. For client use: npm run make:client:<host>`
    )
  }

  const results = []
  for (const host of opts.hosts) {
    results.push(await buildOne(host, opts.outRoot))
  }
  console.log('[bare-standalone] done:', results.join(', '))
}

main().catch((err) => {
  console.error(err)
  process.exit(1)
})