import { GoogleGenAI, Type } from "@google/genai";

const BOOK_DATA_SCHEMA = {
  type: Type.OBJECT,
  properties: {
    title: { type: Type.STRING, description: 'Title of the book' },
    author: { type: Type.STRING, description: 'Author of the book' },
    genre: { type: Type.STRING, description: 'Main genre of the book' },
    annotation: { type: Type.STRING, description: 'Brief summary or annotation' },
    pages: { type: Type.NUMBER, description: 'Approximate number of pages' },
    language: { type: Type.STRING, description: 'Language of the book' },
    publishedYear: { type: Type.NUMBER, description: 'Approximate publication year' }
  },
  required: ['title', 'author', 'genre']
};

export async function extractBookData(base64Image: string) {
  // Ensure we use the exact initialization pattern from guidelines
  const ai = new GoogleGenAI({ apiKey: process.env.API_KEY });
  
  try {
    // Use gemini-3-flash-preview for multimodal extraction tasks
    const response = await ai.models.generateContent({
      model: 'gemini-3-flash-preview',
      contents: {
        parts: [
          { 
            inlineData: { 
              mimeType: 'image/jpeg', 
              data: base64Image.replace(/^data:image\/[a-z]+;base64,/, "") 
            } 
          },
          { text: "Identify this book from the cover. Extract the title, author, genre, and a brief annotation in Russian. Return the information in structured JSON format." }
        ]
      },
      config: {
        responseMimeType: "application/json",
        responseSchema: BOOK_DATA_SCHEMA
      }
    });

    const text = response.text;
    if (!text) throw new Error("No response from model");
    
    return JSON.parse(text);
  } catch (error: any) {
    console.error("Failed to extract book data:", error);
    // Log specific details if available
    if (error.message) {
      console.error("Error Message:", error.message);
    }
    throw error;
  }
}