package io.youtrackdb;

import com.jetbrains.youtrackdb.api.DatabaseType;
import com.jetbrains.youtrackdb.api.YourTracks;
import com.jetbrains.youtrackdb.api.gremlin.YTDBDemoGraphFactory;
import com.jetbrains.youtrackdb.internal.core.gremlin.io.YTDBIoRegistry;
import org.apache.tinkerpop.gremlin.structure.io.graphson.GraphSONMapper;
import org.apache.tinkerpop.gremlin.structure.io.graphson.GraphSONVersion;

import java.util.List;

import static org.apache.tinkerpop.gremlin.process.traversal.P.gt;

/// Minimal example of usage of YouTrackDB.
public class Example {

  public static void main(String[] args) throws Exception {
    //Create a YouTrackDB database manager instance and provide the root folder where all databases will be stored
    // We work with inmemory databases here, so we use "." as a root folder
    try (var ytdb = YourTracks.instance(".")) { //use YourTracks.instance("localhost", "root-name", "root-password") if you want to connect to server
      //Create the database with demo data to play with it
      try (var traversalSource = YTDBDemoGraphFactory.createModern(ytdb)) {
         //Prepare GraphSONMapper to check our results
         var jsonMapper = GraphSONMapper.build()
                 .version(GraphSONVersion.V1_0) // use the simplest version for brevity
                 .addRegistry(YTDBIoRegistry.instance())//add serializer for custom types
                 .create().createMapper();
         
        //YTDB data manipulation is performed inside a transaction, so let us start one.
        //YTDBGraphTraversal will start transaction automatically if it is not started yet.
        //But in such a case you will need to commit it manually, and borders of transaction will be diluted,
        //we suggest using lambda-style API to automatically start/commit/rollback transactions.
        traversalSource.executeInTx(g -> {
          //Find a vertex with class "person" and property "name" equals to "marko".
          var v = g.V().has("person", "name", "marko").next();
          System.out.println("output:" + jsonMapper.writeValueAsString(v));
          //output:{
          //  "id":{..},
          //  "label":"person",
          //  "type":"vertex",
          //  "properties":{
          //    "name":[{"id":{..},"value":"marko"}],
          //    "age":[{"id":{..},"value":29}]
          //   }
          // }
          // there is ongoing change to implement conversion of vertices from/to native JSON
          // by using additional metadata provided by DB schema.
          //
          //Get the names of the people the vertex knows who are over the age of 30.
          var friendNames = g.V(v.id()).out("knows").has("age",
              gt(30)).<String>values("name").toList();
          System.out.println("output:" + String.join(", ", friendNames));
          //output: josh
        });

        //Create an empty database with the name "tg", username "superuser", admin role and password "adminpwd".
        ytdb.create("tg", DatabaseType.MEMORY, "superuser", "adminpwd", "admin");
        //and then open the YTDBGraphGraphTraversal instance
        try (var newTraversal = ytdb.openTraversal("tg", "superuser", "adminpwd")) {
          newTraversal.executeInTx(g -> {
            //create a vertex with class(label) "person" and properties' name and age.
            var v1 = g.addV("person").property("name", "marko").property("age", 29).next();
            System.out.println("output:" + jsonMapper.writeValueAsString(v1));
            // output : {
            //        "id":{..},
            //        "label":"person",
            //        "type":"vertex",
            //        "properties": {
            //          "name": [{"id":{...}, "value":"marko"}],
            //          "age":[{"id":{ ...}, "value":29}]
            //       }
            //  }

            // create a vertex with class(label) "software" and properties' name and lang.
            var v2 = g.addV("software").property("name", "lop").property("lang", "java").next();
            //connect both vertices by "created" relation.
            // we need to call iterate() here to execute traversal flow.
            g.addE("created").from(v1).to(v2).property("weight", 0.4).iterate();
          });

          //let us check the results of data modification after commit
          traversalSource.executeInTx(g -> {
            var createdSoftware = g.V().has("person", "name", "marko").out(
                "created").<String>values("name").toList();
            System.out.println("output:" + String.join(", ", createdSoftware));
            //output: lop
          });
        }
      }
    }
  }
}