import JSZip from 'jszip'

export type BuildZipInput = {
  html: string
  css: string
  js: string
  assets?: Record<string, Uint8Array>
  // root-level extra files like favicon.ico, site.webmanifest, robots.txt
  extras?: Record<string, Uint8Array>
}

export async function buildZip(input: BuildZipInput): Promise<Uint8Array> {
  const zip = new JSZip()
  zip.file('index.html', input.html)
  zip.file('styles.css', input.css)
  zip.file('app.js', input.js)

  // guard: basic path sanitizer to avoid directory traversal or absolute paths
  const isSafePath = (p: string) => {
    if (!p || typeof p !== 'string') return false
    if (p.startsWith('/')) return false
    if (p.includes('..')) return false
    if (p.includes('\\')) return false
    return true
  }

  if (input.assets) {
    for (const [path, bytes] of Object.entries(input.assets)) {
      if (!isSafePath(path)) throw new Error(`Invalid asset path: ${path}`)
      // In Node/Vitest, use Buffer for robust binary handling
      const buf = Buffer.from(bytes)
      zip.file(path, buf as unknown as Buffer)
    }
  }
  if (input.extras) {
    // validate manifest if present
    if (Object.prototype.hasOwnProperty.call(input.extras, 'site.webmanifest')) {
      try {
        const manifestBytes = input.extras['site.webmanifest']
        const manifestStr = Buffer.from(manifestBytes).toString('utf8')
        JSON.parse(manifestStr)
      } catch {
        throw new Error('Invalid site.webmanifest JSON')
      }
    }
    for (const [path, bytes] of Object.entries(input.extras)) {
      if (!isSafePath(path)) throw new Error(`Invalid extra path: ${path}`)
      const buf = Buffer.from(bytes)
      zip.file(path, buf as unknown as Buffer)
    }
  }
  const content = await zip.generateAsync({ type: 'uint8array' })
  return content
}