using System;
using MongoDB.Driver;
using MongoDB.Bson;
using MongoDB.Bson.Serialization.Attributes;

namespace TestAggregation
{
    public class RunData
    {
        [BsonElement("_id")]
        [BsonId]
        public string Id { get; set; }

        [BsonElement("IdClx")]
        public string IdClx { get; set; }
    }

    public class RunDataFull : RunData
    {
        public Clx[] RefClx { get; set; }
    }

    public class Clx
    {
        [BsonElement("_id")]
        [BsonId]
        public string Id { get; set; }
        [BsonElement("BaseClx")]
        public string BaseClx { get; set; }
        [BsonElement("Name")]
        public string Name { get; set; }
    }

    public class ClxFull : Clx
    {
        public Clx[] RefBase { get; set; }
    }

    class Program
    {

        static void Main(string[] args)
        {
            // create the data
            RunData myRunData = new RunData();
            myRunData.Id = "1";
            myRunData.IdClx = "2";

            Clx myClx = new Clx();
            myClx.Id = "2";
            myClx.BaseClx = "BaseClx";
            myClx.Name = "MyClx";

            Clx baseClx = new Clx();
            baseClx.Id = "3";
            baseClx.BaseClx = null;
            baseClx.Name = "BaseClx";

            // write in the DB
            var client = new MongoClient("mongodb://localhost");
            var db = client.GetDatabase("testDbAggr");
            db.DropCollection("clxColl");
            var clxColl = db.GetCollection<Clx>("clxColl");
            clxColl.InsertOne(myClx);
            clxColl.InsertOne(baseClx);
            db.DropCollection("runColl");
            var runColl = db.GetCollection<RunData>("runColl");
            runColl.InsertOne(myRunData);

            // queries
            var filter = Builders<Clx>.Filter.Ne<Clx>("BaseClx", null) ;
            var clxList = clxColl
                .Aggregate()
                .Match(filter)
                .Lookup(
                    clxColl,
                    m => m.BaseClx,
                    c => c.Name,
                    (ClxFull m) => m.RefBase
                    )
                .ToList();

            var runDataList = runColl
                .Aggregate()
                .Lookup(
                    clxColl,
                    m => m.IdClx,
                    c => c.Id,
                    (RunDataFull m) => m.RefClx
                    )
                .ToList();

            Console.WriteLine("Done!");
        }
    }
}