/*
 * Copyright 2016 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/*
 * EDITING INSTRUCTIONS
 * This file is referenced in READMEs and javadoc. Any change to this file should be reflected in
 * the project's READMEs and package-info.java.
 */

package com.google.cloud.examples.datastore.snippets;

import com.google.cloud.datastore.Datastore;
import com.google.cloud.datastore.DatastoreOptions;
import com.google.cloud.datastore.Entity;
import com.google.cloud.datastore.Key;
import com.google.cloud.datastore.KeyFactory;
import com.google.cloud.datastore.Query;
import com.google.cloud.datastore.QueryResults;
import com.google.cloud.datastore.StructuredQuery.PropertyFilter;

/**
 * A snippet for Google Cloud Datastore showing how to create and get entities. The snippet also
 * shows how to run a query against Datastore.
 */
public class AddEntitiesAndRunQuery {

  public static void main(String... args) {
    // Create datastore service object.
    // By default, credentials are inferred from the runtime environment.
    Datastore datastore = DatastoreOptions.getDefaultInstance().getService();

    // Add an entity to Datastore
    KeyFactory keyFactory = datastore.newKeyFactory().setKind("Person");
    Key key = keyFactory.newKey("john.doe@gmail.com");
    Entity entity = Entity.newBuilder(key)
        .set("name", "John Doe")
        .set("age", 51)
        .set("favorite_food", "pizza")
        .build();
    datastore.put(entity);

    // Get an entity from Datastore
    Entity johnEntity = datastore.get(key);

    // Add a couple more entities to make the query results more interesting
    Key janeKey = keyFactory.newKey("jane.doe@gmail.com");
    Entity janeEntity = Entity.newBuilder(janeKey)
        .set("name", "Jane Doe")
        .set("age", 44)
        .set("favorite_food", "pizza")
        .build();
    Key joeKey = keyFactory.newKey("joe.shmoe@gmail.com");
    Entity joeEntity = Entity.newBuilder(joeKey)
        .set("name", "Joe Shmoe")
        .set("age", 27)
        .set("favorite_food", "sushi")
        .build();
    datastore.put(janeEntity, joeEntity);

    // Run a query
    Query<Entity> query = Query.newEntityQueryBuilder()
        .setKind("Person")
        .setFilter(PropertyFilter.eq("favorite_food", "pizza"))
        .build();
    QueryResults<Entity> results = datastore.run(query);
    while (results.hasNext()) {
      Entity currentEntity = results.next();
      System.out.println(currentEntity.getString("name") + ", you're invited to a pizza party!");
    }
  }
}
