export interface SystemDesignTopic {
  id: string;
  chapter_no: number;
  chapter_name: string;
  subtitle: string;
  level: string;
}

export interface SystemDesignTopicContent extends SystemDesignTopic {
  content: any; // Raw JSON object from MongoDB
}

export async function fetchSystemDesignTopics(): Promise<SystemDesignTopic[]> {
  const res = await fetch('/api/system-design/topics');
  if (!res.ok) throw new Error('Failed to fetch topics');
  const data = await res.json();
  return data.topics || [];
}

export async function fetchSystemDesignTopicContent(chapterNo: number): Promise<SystemDesignTopicContent> {
  const res = await fetch(`/api/system-design/topics/${chapterNo}`);
  if (!res.ok) throw new Error('Failed to fetch topic content');
  return res.json();
}