#!/usr/bin/env node
/**
 * Verify a harness tree is self-contained and actually boots from the bundle.
 *
 * Default: check the assembled `build/harness`. With `--app <dir>`, locate the
 * `resources/harness` inside a packed/unpacked app instead — this additionally
 * proves electron-builder's `extraResources` copy preserved the relative
 * in-tree links. `--boot` also spawns the web profile straight from the bundle
 * (temp DSH_HOME, telemetry off) and waits for its readiness line, proving the
 * relinked node_modules resolves without the repository present.
 *
 * Usage:
 *   node scripts/verify-harness.mjs                  # build/harness
 *   node scripts/verify-harness.mjs --boot           # + web boot smoke
 *   node scripts/verify-harness.mjs --app dist       # a packed app's harness
 *   node scripts/verify-harness.mjs --app dist --boot
 */

import { spawn, spawnSync } from 'node:child_process'
import { existsSync, mkdtempSync, readdirSync, rmSync } from 'node:fs'
import { tmpdir } from 'node:os'
import { basename, dirname, isAbsolute, join, resolve } from 'node:path'
import { fileURLToPath } from 'node:url'
import { assertSelfContained } from './harness-relink.mjs'

const root = resolve(dirname(fileURLToPath(import.meta.url)), '../../..')
const desktopDir = join(root, 'apps/desktop')
const defaultHarness = join(desktopDir, 'build/harness')

const args = process.argv.slice(2)
const boot = args.includes('--boot')
const appIndex = args.indexOf('--app')
const appValue = args.find((a) => a.startsWith('--app='))?.slice('--app='.length) ?? (appIndex !== -1 ? args[appIndex + 1] : undefined)
const appRoot = appValue === undefined
  ? undefined
  : isAbsolute(appValue)
    ? resolve(appValue)
    : resolve(desktopDir, appValue)

const timeoutMs = 60_000
const READY_RE = /http:\/\/127\.0\.0\.1:(\d+)/

function fail(message) {
  console.error(`verify-harness: ${message}`)
  process.exit(1)
}

/** Find every `resources/harness` under an unpacked electron-builder app. */
function findHarnessUnder(appDir) {
  const found = []
  // electron-builder unpacked layout:
  //   win: <root>/win-unpacked/resources/harness
  //   mac: <root>/mac(-arch)/<Name>.app/Contents/Resources/harness
  const visit = (dir, depth) => {
    if (depth > 5) return
    let entries
    try {
      entries = readdirSync(dir, { withFileTypes: true })
    } catch {
      return
    }
    for (const entry of entries) {
      const p = join(dir, entry.name)
      if (basename(p) === 'harness' && basename(dirname(p)) === 'resources') found.push(p)
      if (entry.isDirectory()) visit(p, depth + 1)
    }
  }
  visit(appDir, 0)
  return found
}

function nodeBinary(harness) {
  return join(harness, 'bin', process.platform === 'win32' ? 'node.exe' : 'node')
}

function cliEntry(harness) {
  return join(harness, 'apps/cli/lib/bin.js')
}

/** Run the bundled CLI's `--version` straight from the bundle. */
function checkVersion(harness) {
  const result = spawnSync(nodeBinary(harness), [cliEntry(harness), '--version'], {
    cwd: harness,
    encoding: 'utf8',
    timeout: timeoutMs,
  })
  if (result.error !== undefined || result.status !== 0) {
    fail(`the bundled CLI failed to run: ${result.error?.message ?? result.stderr?.trim() ?? `exit ${String(result.status)}`}`)
  }
  console.log(`  dsh --version: ${result.stdout?.trim()}`)
}

/**
 * Spawn the web profile from the bundle and resolve once it prints its
 * readiness URL. Hermetic: a temp DSH_HOME and telemetry off, so the check
 * neither touches the real profile nor the repository.
 */
function bootWeb(harness) {
  const home = mkdtempSync(join(tmpdir(), 'dsh-verify-home-'))
  const child = spawn(
    nodeBinary(harness),
    [cliEntry(harness), '--profile', 'web', '--host', '127.0.0.1', '--port', '0'],
    {
      cwd: harness,
      stdio: ['ignore', 'pipe', 'inherit'],
      env: { ...process.env, DSH_HOME: home, DSH_TELEMETRY_DISABLED: '1', DSH_ALLOW_PLUGIN_INSTALL: '1' },
    },
  )
  return new Promise((resolvePromise, reject) => {
    let settled = false
    let buffered = ''
    const cleanup = () => {
      try {
        rmSync(home, { recursive: true, force: true })
      } catch {
        // Best effort; a locked file on Windows is not fatal for a verify tool.
      }
    }
    const timer = setTimeout(() => {
      if (settled) return
      settled = true
      child.kill()
      cleanup()
      reject(new Error(`web boot timed out after ${timeoutMs}ms`))
    }, timeoutMs)
    child.stdout?.setEncoding('utf8')
    child.stdout?.on('data', (chunk) => {
      if (settled) return
      buffered += chunk
      if (READY_RE.test(buffered)) {
        settled = true
        clearTimeout(timer)
        child.kill()
        cleanup()
        resolvePromise()
      }
    })
    child.on('error', (error) => {
      if (settled) return
      settled = true
      clearTimeout(timer)
      cleanup()
      reject(error)
    })
    child.on('exit', (code) => {
      if (settled) return
      settled = true
      clearTimeout(timer)
      cleanup()
      reject(new Error(`harness exited before serving (code ${String(code)})`))
    })
  })
}

async function main() {
  const harness = (() => {
    if (appRoot !== undefined) {
      const found = findHarnessUnder(appRoot)
      if (found.length === 0) fail(`no resources/harness found under ${appRoot}`)
      if (found.length > 1) {
        console.warn(`verify-harness: ${found.length} harness dirs found; checking the first:\n  ${found.join('\n  ')}`)
      }
      return found[0]
    }
    if (!existsSync(defaultHarness)) fail(`build/harness not found at ${defaultHarness} — run build:harness first`)
    return defaultHarness
  })()

  console.log(`verify-harness: ${harness}`)
  if (!existsSync(nodeBinary(harness))) fail(`bundled node not found at ${nodeBinary(harness)}`)
  try {
    assertSelfContained(harness)
  } catch (error) {
    fail(error instanceof Error ? error.message : String(error))
  }
  console.log('  links: self-contained (no link escapes the bundle)')
  checkVersion(harness)
  if (boot) {
    try {
      await bootWeb(harness)
    } catch (error) {
      fail(error instanceof Error ? error.message : String(error))
    }
    console.log('  web boot: ok')
  }
  console.log('verify-harness: ok')
}

main().catch((error) => fail(error instanceof Error ? error.message : String(error)))