const { Book, Location, Checkout, User, Sequelize, Op } = require('./models');
const axios = require('axios');

// Fetch book from the local database by ISBN
const fetchBookFromLocalDatabase = async (isbn) => {
    return await Book.findOne({ 
        where: { isbn },
        include: [{
            model: Location,
            as: 'Location'
        }]
    });
};

// Fetch book from Google Books API
const fetchBookFromGoogleBooks = async (isbn, apiKey) => {
    try {
        const response = await axios.get(`https://www.googleapis.com/books/v1/volumes?q=${isbn}&key=${apiKey}`);
        if (response.data.items && response.data.items.length > 0) {
            return library.formatGoogleBooksData(response.data.items[0]);
        }
        return null;
    } catch (error) {
        if (error.response && (error.response.status === 429 || error.response.status === 408)) {
            throw error.response.status;
        }
        throw new Error('Google Books API Error');
    }
};

// Fetch book from Open Library API
const fetchBookFromOpenLibrary = async (isbn) => {
    try {
        const response = await axios.get(`https://openlibrary.org/api/books?bibkeys=ISBN:${isbn}&format=json&jscmd=data`);
        return response.data[`ISBN:${isbn}`] ? library.formatOpenLibraryData(response.data[`ISBN:${isbn}`]) : null;
    } catch (error) {
        if (error.response && (error.response.status === 429 || error.response.status === 408)) {
            throw error.response.status;
        }
        throw new Error('Open Library API Error');
    }
};

// Fetch book from the Internet Archive
const fetchBookFromInternetArchive = async (isbn) => {
    try {
        const response = await axios.get(`https://openlibrary.org/api/books?bibkeys=ISBN:${isbn}&format=json&jscmd=data`);
        return response.data[`ISBN:${isbn}`] ? library.formatArchiveData(response.data[`ISBN:${isbn}`]) : null;
    } catch (error) {
        throw new Error('Internet Archive API Error');
    }
};

// Search books in the local database by title or related fields
const searchBooksInLocalDatabase = async (title, searchDescription=false) => {
    if (!title) {
        // Return all books if the title is empty
        return await Book.findAll();
    }

    const searchConditions = [
        { title: { [Op.like]: `%${title}%` } },
        { authors: { [Op.like]: `%${title}%` } },
        { publishers: { [Op.like]: `%${title}%` } },
        { subjects: { [Op.like]: `%${title}%` } }
    ];

    if (searchDescription) {
        searchConditions.push({ description: { [Op.like]: `%${title}%` } });
    }

    return await Book.findAll({
        where: {
            [Op.or]: searchConditions
        }
    });
};

// Search books in Open Library by title
const searchBooksInOpenLibrary = async (title) => {
    try {
        const response = await axios.get(`https://openlibrary.org/search.json?q=${encodeURIComponent(title)}&limit=7`);
        return response.data.docs.map(result => ({
            title: result.title,
            authors: result.author_name || [],
            publish_date: result.first_publish_year,
            isbn: result.isbn ? result.isbn[0] : '',
            publisher: result.publisher ? result.publisher[0] : '',
            key: result.key
        }));
    } catch (error) {
        throw new Error('Open Library API Error');
    }
};

module.exports = {
    fetchBookFromLocalDatabase,
    fetchBookFromGoogleBooks,
    fetchBookFromOpenLibrary,
    fetchBookFromInternetArchive,
    searchBooksInLocalDatabase,
    searchBooksInOpenLibrary
};