export async function embedText(text: string, apiKey?: string): Promise<number[]> {
  const key = apiKey ?? process.env.GOOGLE_AI_API_KEY
  if (!key) throw new Error('GOOGLE_AI_API_KEY is not set')
  const res = await fetch(
    `https://generativelanguage.googleapis.com/v1beta/models/text-embedding-004:embedContent?key=${key}`,
    {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        model: 'models/text-embedding-004',
        content: { parts: [{ text }] },
      }),
    }
  )
  if (!res.ok) throw new Error(`Gemini embed failed: ${res.status}`)
  const json = await res.json() as { embedding: { values: number[] } }
  return json.embedding.values
}