// Author: Dr Hamid MADANI <drmdh@msn.com>
import { NextRequest, NextResponse } from 'next/server'
import { createReadStream, statSync } from 'fs'
import path from 'path'
import { Readable } from 'stream'

export const runtime = 'nodejs'
export const dynamic = 'force-dynamic'

const ROOT = path.join(process.cwd(), 'data', 'records')
const SAFE = /^[a-zA-Z0-9_-]{1,128}$/

export async function GET(
  _req: NextRequest,
  { params }: { params: Promise<{ sessionId: string }> },
) {
  const { sessionId } = await params
  if (!SAFE.test(sessionId)) {
    return NextResponse.json({ error: 'invalid sessionId' }, { status: 400 })
  }
  const fp = path.join(ROOT, `${sessionId}.webm`)
  let size: number
  try { size = statSync(fp).size }
  catch { return NextResponse.json({ error: 'not found' }, { status: 404 }) }

  const node = createReadStream(fp)
  const web = Readable.toWeb(node) as unknown as ReadableStream
  return new NextResponse(web, {
    status: 200,
    headers: {
      'Content-Type': 'video/webm',
      'Content-Length': String(size),
      'Cache-Control': 'no-store',
    },
  })
}