import { chromium } from 'playwright'
import { mkdirSync, existsSync, readdirSync, readFileSync } from 'fs'
import { resolve, dirname } from 'path'
import { fileURLToPath } from 'url'

const __dirname = dirname(fileURLToPath(import.meta.url))
const PROFILE_DIR   = resolve(__dirname, '../sessions/chrome-profile')
const SNAPSHOTS_DIR = resolve(__dirname, '../sessions/snapshots')
const INJECT_SRC    = resolve(__dirname, './inject.browser.js')

const PUBLIC_BASE = process.env.BEACON_PUBLIC_URL || `http://localhost:${process.env.BEACON_PORT || 3700}`

// Inject script with beacon base URL substituted in
function buildInjectScript() {
  return readFileSync(INJECT_SRC, 'utf8').replaceAll('__BEACON_BASE__', PUBLIC_BASE)
}

// Wire auto-inject onto a context — fires on every new page that opens
function attachInject(context) {
  const script = buildInjectScript()
  // addInitScript runs before any page JS — functions are available immediately
  context.addInitScript(script).catch(() => {})
}

const IS_MAC = process.platform === 'darwin'
const IS_HF  = !!process.env.SPACE_ID   // HuggingFace injects this

let _context = null
let _browser  = null  // only set in non-persistent launch

export async function getContext() {
  if (_context) return _context

  mkdirSync(PROFILE_DIR, { recursive: true })
  mkdirSync(SNAPSHOTS_DIR, { recursive: true })

  // ── Mac path ──────────────────────────────────────────────────────────────

  if (IS_MAC && !IS_HF) {
    // 1. CDP bridge — rides your already-running Chrome (zero copy)
    //    Enable with: open -a "Google Chrome" --args --remote-debugging-port=9222
    try {
      const browser = await chromium.connectOverCDP('http://localhost:9222', { timeout: 2000 })
      const contexts = browser.contexts()
      _context = contexts[0] ?? await browser.newContext()
      attachInject(_context)
      console.log('[beacon] CDP bridge — live Chrome session active')
      return _context
    } catch {}

    // 2. Chrome profile clone (npm run sync-profile)
    const hasProfile = existsSync(`${PROFILE_DIR}/Cookies`)
    _context = await chromium.launchPersistentContext(PROFILE_DIR, {
      channel: 'chrome',
      headless: true,
      viewport: { width: 1280, height: 900 },
      userAgent: 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36',
      args: ['--no-sandbox', '--disable-blink-features=AutomationControlled'],
      ignoreDefaultArgs: ['--enable-automation'],
    })
    attachInject(_context)
    console.log(hasProfile
      ? '[beacon] Chrome profile loaded — all sessions active'
      : '[beacon] Fresh profile — run: npm run sync-profile')
    return _context
  }

  // ── Linux / HuggingFace path ──────────────────────────────────────────────
  // No local Chrome. Load auth from committed session snapshots instead.

  const storageState = mergeSnapshots(SNAPSHOTS_DIR)

  _browser = await chromium.launch({
    headless: true,
    args: [
      '--no-sandbox',
      '--disable-dev-shm-usage',
      '--disable-blink-features=AutomationControlled',
    ],
  })

  _context = await _browser.newContext({
    storageState: storageState || undefined,
    viewport: { width: 1280, height: 900 },
    userAgent: 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36',
    ignoreHTTPSErrors: false,
  })
  attachInject(_context)

  const snapshotCount = storageState?.cookies?.length ?? 0
  console.log(snapshotCount > 0
    ? `[beacon] Loaded ${snapshotCount} cookies from session snapshots`
    : '[beacon] No snapshots found — browsing anonymously')

  return _context
}

// Merge all snapshot JSON files into a single storageState object
function mergeSnapshots(dir) {
  const files = readdirSync(dir).filter(f => f.endsWith('.json'))
  if (!files.length) return null

  const cookies = []
  const origins = []

  for (const file of files) {
    try {
      const state = JSON.parse(readFileSync(`${dir}/${file}`, 'utf8'))
      if (state.cookies) cookies.push(...state.cookies)
      if (state.origins) origins.push(...state.origins)
    } catch {}
  }

  return { cookies, origins }
}

export async function closeContext() {
  if (_context) { await _context.close(); _context = null }
  if (_browser)  { await _browser.close();  _browser  = null }
}