/src/main/java/com/hackatravel/travelplace/daos/GenericDao.java

package com.hackatravel.travelplace.daos;

import com.google.gson.Gson;
import com.hackatravel.travelplace.model.ModelItem;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import org.bson.Document;
import org.springframework.beans.factory.annotation.Autowired;

import java.util.ArrayList;
import java.util.List;

public abstract class GenericDao {

    @Autowired
    protected MongoDatabase mongoDatabase;

    abstract MongoCollection<Document> getCollection();

    private Gson gson = new Gson();

    protected <T> void insertDocument(T object) {
        getCollection().insertOne(objectToDocument(object));
    }

    protected <T> List<T> getDocuments(Document query, Document sort, Class<T> clazz) {
        List<T> result = new ArrayList<>();
        FindIterable<Document> documents = getCollection().find(query);
        if (sort != null) {
            documents = documents.sort(sort);
        }
        for (Document document : documents) {
            String documentString = document.toJson();
            T object = gson.fromJson(documentString, clazz);
            result.add(object);
        }

        return result;
    }

    protected <T extends ModelItem> void updateDocument(T object) {
        getCollection().findOneAndUpdate(new Document("id", object.getId()), objectToDocument(object));
    }

    protected void deleteDocument(String id) {
        getCollection().deleteMany(new Document("id", id));
    }

    private <T> Document objectToDocument(T object) {
        String documentString = gson.toJson(object);
        return Document.parse(documentString);
    }

    protected Document getIdDocument(String id) {
        return new Document("id", id);
    }

    protected Document getEmailPasswordDocument(String email, String password) {
        return Document.parse("{ email: /^" + email + "$/i, password: '" + password + "' }");
    }

}