import { createCache } from "@lib/cache.ts";

const HARDCOVER_API_URL = "https://api.hardcover.app/v1/graphql";

const CACHE_INTERVAL = 1000 * 60 * 60 * 24 * 7;
const cache = createCache("hardcover", { expires: CACHE_INTERVAL });

export interface HardcoverBookResult {
  id: string;
  slug: string;
  title: string;
  subtitle?: string;
  author_names: string[];
  cover_color?: string;
  description?: string;
  isbn?: string;
  isbn13?: string;
  release_year?: string;
  series_names?: string[];
  rating?: number;
  ratings_count?: number;
  pages?: number;
  image?: string;
}

async function hardcoverFetch(query: string, variables: Record<string, unknown> = {}) {
  const response = await fetch(HARDCOVER_API_URL, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      "Authorization": Deno.env.get("HARDCOVER_API_TOKEN") || "",
    },
    body: JSON.stringify({ query, variables }),
  });

  if (!response.ok) {
    throw new Error(`Hardcover API error: ${response.statusText}`);
  }

  const json = await response.json();
  
  if (json.errors) {
    console.error("Hardcover GraphQL errors:", JSON.stringify(json.errors, null, 2));
    throw new Error(`Hardcover GraphQL error: ${json.errors[0]?.message || "Unknown error"}`);
  }
  
  return json;
}

export const searchBook = async (query: string) => {
  const id = `query:booksearch:${query}`;
  if (cache.has(id)) return cache.get(id) as HardcoverBookResult[];

  const graphqlQuery = `
    query SearchBooks($query: String!, $perPage: Int, $page: Int) {
      search(
        query: $query
        query_type: "Book"
        per_page: $perPage
        page: $page
      ) {
        results
      }
    }
  `;

  const result = await hardcoverFetch(graphqlQuery, {
    query,
    perPage: 10,
    page: 1,
  });

  const typesenseResponse = result.data?.search?.results;
  const hits = typesenseResponse?.hits;
  const books = (hits || []).map((hit: { document: HardcoverBookResult }) => hit.document);
  
  cache.set(id, books);
  return books as HardcoverBookResult[];
};

export const getBookDetails = async (id: string) => {
  const cacheId = `query:bookdetails:${id}`;
  if (cache.has(cacheId)) return cache.get(cacheId);

  const graphqlQuery = `
    query GetBook($id: Int!) {
      books(where: { id: { _eq: $id } }) {
        id
        slug
        title
        subtitle
        description
        release_date
        release_year
        rating
        ratings_count
        pages
        cached_image
        cached_contributors
        featured_book_series {
          series {
            id
            name
            slug
          }
        }
        editions(limit: 1) {
          isbn_10
          isbn_13
        }
      }
    }
  `;

  const result = await hardcoverFetch(graphqlQuery, { id: parseInt(id) });
  
  const bookData = result.data?.books?.[0];
  
  if (bookData) {
    const isbn13 = bookData.editions?.[0]?.isbn_13;
    const isbn10 = bookData.editions?.[0]?.isbn_10;
    
    const cachedContributors = bookData.cached_contributors as Array<{ author: { name: string }; contribution: string }> | undefined;
    const authorName = cachedContributors?.[0]?.author?.name;
    
    const book = {
      ...bookData,
      isbn: isbn13 || isbn10 || "",
      isbn13,
      isbn10,
      author_names: authorName ? [authorName] : [],
      image: bookData.cached_image?.url,
    };
    
    cache.set(cacheId, book);
    return book;
  }
  
  return null;
};