// Recover only the loading component rules used by StreamingFooter from REA-exported CSS.
// This reads the saved REA export, never the WorkBuddy installation or runtime directly.
import assert from 'node:assert/strict'
import { createHash } from 'node:crypto'
import { readFile, writeFile } from 'node:fs/promises'
import path from 'node:path'
import postcss from 'postcss'

const sourceDirectory = path.resolve('.tmp/rea-css-recovered')
const destination = path.resolve('src/renderer/src/workbuddy/conversation/streaming-footer-source.css')
const evidenceId = 'ev_377c8790468b3c67dad8577aabb327f98d3140659f0fffdbabfcff5a40cc9e94'
const manifest = JSON.parse(await readFile(path.join(sourceDirectory, 'manifest.json'), 'utf8'))
assert.equal(manifest.sourceEvidenceId, evidenceId)

const sourceFiles = [
  { file: 'src-CBaV_A3S.css', sha256: '2090ed21045c8f8b0fc388d76424c8751bf18fcd065cbbd5d0ef485163a2e36c' },
  { file: 'contexts-BkjwYSZT.css', sha256: '50cbd673f7f35fc7f966bdddc6c9f5677fdfe944cb904888d214619fca259380' }
]
const classNames = [
  'assistant-message',
  '_loadingMessage_13r4w_60',
  '_loadingContent_13r4w_69',
  '_loadingText_13r4w_81',
  '_mainText_13r4w_94',
  '_tipPhrase_13r4w_108',
  '_tipDivider_13r4w_121',
  '_tipText_13r4w_126',
  '_tipDismissButton_13r4w_140',
  '_trailingTipPhrase_13r4w_179',
  '_loadingWithCredit_ttf8p_463',
  'cb-loading-tip--trailing'
]

const output = postcss.root()
const usedAnimations = new Set()
const sourceIdentities = []

function referencesClass(selector) {
  return classNames.some(name => new RegExp(`\\.${name.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')}(?![\\w-])`).test(selector))
}

function copyRelevantNodes(nodes) {
  const copied = []
  for (const node of nodes) {
    if (node.type === 'rule') {
      const selectors = (node.selectors ?? []).filter(referencesClass)
      if (!selectors.length) continue
      const clone = node.clone({ selector: selectors.join(',') })
      clone.walkDecls(/^animation(?:-name)?$/, declaration => {
        for (const token of declaration.value.split(/[\s,]+/)) usedAnimations.add(token)
      })
      copied.push(clone)
      continue
    }
    if (node.type === 'atrule' && /keyframes$/.test(node.name)) continue
    if (node.type === 'atrule' && node.nodes) {
      const children = copyRelevantNodes(node.nodes)
      if (children.length) copied.push(node.clone({ nodes: children }))
    }
  }
  return copied
}

for (const expected of sourceFiles) {
  const metadata = manifest.files.find(file => file.file === expected.file)
  assert.ok(metadata, `REA CSS export must contain ${expected.file}`)
  assert.equal(metadata.sha256, expected.sha256, `REA CSS manifest digest changed for ${expected.file}`)
  const bytes = await readFile(path.join(sourceDirectory, expected.file))
  assert.equal(createHash('sha256').update(bytes).digest('hex'), expected.sha256, `REA CSS bytes changed for ${expected.file}`)
  const source = postcss.parse(bytes, { from: expected.file })
  for (const node of copyRelevantNodes(source.nodes)) output.append(node)
  source.walkAtRules(/^keyframes$/, node => {
    if (usedAnimations.has(node.params)) output.append(node.clone())
  })
  sourceIdentities.push({ file: expected.file, sha256: expected.sha256, asarComparison: metadata.asarComparison?.status ?? 'not-compared' })
}

for (const name of classNames) {
  assert.ok(output.toString().includes(`.${name}`), `REA CSS export is missing the ${name} rule`)
}
assert.ok(output.toString().includes('@keyframes _cb-shining-text-sweep_13r4w_1'))
assert.ok(output.toString().includes('@keyframes _cb-tip-fade-in_13r4w_1'))

const header = `/* Generated from REA ${evidenceId} by recover-streaming-footer-styles.mjs.
 * Selected WorkBuddy 5.8.2 loading component rules are preserved verbatim.
 * Runtime CSS identities: ${sourceIdentities.map(item => `${item.file}=${item.sha256} (${item.asarComparison})`).join('; ')}
 */\n`
const result = header + output.toString() + '\n'

if (process.argv.includes('--check')) {
  assert.equal(await readFile(destination, 'utf8'), result, 'Recovered streaming footer styles are stale')
  console.log(`streaming footer styles check passed (${classNames.length} class families; ${sourceIdentities.length} REA CSS assets)`)
} else {
  await writeFile(destination, result, 'utf8')
  console.log(`recovered streaming footer styles to ${destination}`)
}