from pymongo import MongoClient
from bson.objectid import ObjectId
class AnimalShelter(object):
    """ CRUD operations for Animal collection in MongoDB """

    def __init__(self):
        # Initializing the MongoClient. This helps to
        # access the MongoDB databases and collections.
        # This is hard-wired to use the aac database, the
        # animals collection, and the aac user.
        # Definitions of the connection string variables are
        # unique to the individual Apporto environment.
        #
        # You must edit the connection variables below to reflect
        # your own instance of MongoDB!
        #
        # Connection Variables
        #
        USER = 'aacuser'
        PASS = 'Ex9Ai3Y2eP'
        HOST = 'db'
        PORT = 27017
        DB = 'AAC'
        COL = 'animals'
        #
        # Initialize Connection
        #
        self.client = MongoClient('mongodb://%s:%s@%s:%d' % (USER,PASS,HOST,PORT))
        self.database = self.client['%s' % (DB)]
        self.collection = self.database['%s' % (COL)]

# Complete this create method to implement the C in CRUD.
    def create(self, *args, **kwargs):
        data = kwargs.get('data', None)
        if data is not None:
            try:
                self.database.animals.insert_one(data)  # data should be dictionary
            except Exception as e:
                raise Exception(f'Error: {e}')
        else:
            raise Exception("Nothing to save, because data parameter is empty")

# Create method to implement the R in CRUD.
    def read(self, *args, **kwargs):
        criteria = kwargs.get('criteria', None)
        find_one = kwargs.get('once', False)

        if find_one:
            try:
                data = self.collection.find_one(criteria)
                return data
            except Exception as e:
                raise Exception(f"Error: {e}")
        else:
            try:
                data = self.collection.find(criteria)
                return data
            except Exception as e:
                raise Exception(f"Error: {e}")