const mongodb = require('mongodb');
const assert = require('assert');

const mongoConfig = {
    url: 'mongodb://localhost:27017',
    username: 'express-user',
    password: 'P@ssword1',
    database: 'express-test'
};

class Mongo {
    constructor() {
        mongodb.MongoClient.connect(mongoConfig.url, (err, client) => {
            assert.equal(null, err);
            console.log('Connected successfuly to mongodb');
            this.db = client.db(mongoConfig.database);

            this.db.collection('test').find({}, (err, results) => {
                results.forEach(console.log);
            });

            client.close();
        });
    }

    find(collectionName, query, callback) {
        this.db.collection(collectionName).find(query, (error, result) => {
            assert.equal(null, error, `Unable to find ${collectionName} entities: ${error}.`);
            console.log(`Entities ${collectionName} founded.`);
            callback(result);
        });
    }

    insert(collectionName, entity, callback) {
        this.db.collection(collectionName).insert(entity, (error, result) => {
            assert.equal(null, error, `Unable to insert ${collectionName} entity: ${error}.`);
            console.log(`Entity ${collectionName} inserted.`);
            callback(result);
        });
    }

    update(collectionName, entity, query, callback) {
        this.db.collection(collectionName).update(query, entity, (error, result) => {
            assert.equal(null, error, `Unable to update ${collectionName} entity: ${error}.`);
            console.log(`Entity ${collectionName} updated.`);
            callback(result);
        });
    }

    delete(collectionName, entityId, callback) {
        this.db.collection(collectionName).deleteOne({id: entityId}, (error, result) => {
            assert.equal(null, error, `Unable to delete ${collectionName} entity with id ${entityId}: ${error}.`);
            console.log(`Entity ${collectionName} with id ${entityId} deleted.`);
            callback(result);
        });
    }
}

module.exports = Mongo;