import type { NanoBananaRequest, NanoBananaResponse } from '@/types';

const NANO_BANANA_ENDPOINT = 'http://localhost:7879/v1/images/generations';

export async function generateImages(
  req: NanoBananaRequest,
): Promise<NanoBananaResponse> {
  const response = await fetch(NANO_BANANA_ENDPOINT, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
      model: 'nano-banana',
      n: 1,
      response_format: 'b64_json',
      ...req,
    }),
  });

  if (!response.ok) {
    const text = await response.text().catch(() => '');
    throw new Error(`Generation failed (${response.status}): ${text}`);
  }

  const data = (await response.json()) as NanoBananaResponse;
  if (!data.data || data.data.length === 0) {
    throw new Error('No images returned');
  }
  return data;
}

export function b64ToDataUrl(b64: string, format: string = 'png'): string {
  const mime = format === 'jpeg' ? 'image/jpeg' : format === 'webp' ? 'image/webp' : 'image/png';
  return `data:${mime};base64,${b64}`;
}