import requests
import json

class Book:
    def __init__(self, isbn):
        if isbn is None:
            return None

        try:
            isbn = str(isbn).replace("-", "")
            int(isbn)
        except ValueError: # this can be ISBN-10
            pass
            # raise ValueError("ISBN must be an int")

        self.isbn = isbn
        self.title = None
        self.publisher = None
        self.publish_date = None
        self.author = None
        self.category = None
        self.count = -1

    def _openlibrary_load(self, _):
        r = requests.get(f"https://openlibrary.org/api/books?bibkeys=ISBN:{self.isbn}&jscmd=details&format=json")

        if r.status_code != 200:
            raise requests.RequestException(f"Got an error on the request. Status code: {r.status_code}")

        data = json.loads(r.content)

        if f"ISBN:{self.isbn}" not in data:
            raise KeyError("Not found in OpenLibrary")

        isbn_data = data[f"ISBN:{self.isbn}"]

        self.title = isbn_data["details"]["title"]
        if "publishers" in isbn_data["details"] and len(isbn_data["details"]["publishers"]) > 0:
            self.publisher = isbn_data["details"]["publishers"][0]

        if "authors" in isbn_data["details"] and len(isbn_data["details"]["authors"]) > 0:
            self.author = isbn_data["details"]["authors"][0]["name"]

        if "publish_date" in isbn_data["details"]:
            self.publish_date = isbn_data["details"]["publish_date"]

    
    def _google_books_load(self, config):
        if config["GOOGLE_BOOKS_KEY"] is None:
            key_param = ""
        else:
            key_param = f"&key={config['GOOGLE_BOOKS_KEY']}"
        
        r = requests.get(f"https://www.googleapis.com/books/v1/volumes?q=isbn:{self.isbn}{key_param}")

        if r.status_code != 200:
            raise requests.RequestException(f"Got an error on the request. Status code: {r.status_code}")

        data = json.loads(r.content)

        if data["totalItems"] == 0:
            raise KeyError("Not found in Google Books")

        item = data["items"][0]

        self.title = item["volumeInfo"]["title"]

        if "publisher" in item["volumeInfo"]:
            self.publisher = item["volumeInfo"]["publisher"]

        if "publishedDate" in item["volumeInfo"]:
            self.publish_date = item["volumeInfo"]["publishedDate"]

        if "authors" in item["volumeInfo"]:
            self.author = item["volumeInfo"]["authors"][0]


    def _manual_load(self, title, publisher=None, publish_date=None, author=None, count=-1, category=None):
        self.title = title
        self.publisher = publisher
        self.publish_date = publish_date
        self.author = author
        self.count = count
        self.category = category

    def load(self, config, loader="openlibrary"):
        if loader == "openlibrary":
            return self._openlibrary_load(config)
        elif loader == "google_books":
            return self._google_books_load(config)
        else:
            raise ValueError("Invalid loader")

    def __repr__(self):
        if self.title is None:
            return f"<Book: ISBN:{self.isbn}>"
        return f"<Book: {self.title}>"

    def to_json(self):
        return {
            "isbn": self.isbn,
            "title": self.title,
            "publisher": self.publisher,
            "publish_date": self.publish_date,
            "author": self.author,
            "category": self.category,
            "count": self.count,
        }