using System;
using System.Collections.Generic;
using System.Linq;
using MongoDB.Bson;
using MongoDB.Bson.Serialization;
using MongoDB.Driver;

namespace Mongo.Test
{

  public class Person
  {
    public string Name { get; set; }
    public char Gender { get; set; }
    public override string ToString() => $@"{GetType().Name}: ({Gender}) {Name}";
  }


  public class Group
  {
    public ObjectId Id { get; set; } = new ObjectId();
    public string Name { get; set; }
    public List<Person> Members { get; set; }
    public override string ToString() => $@"{GetType().Name}: {Id}, Name: {Name}, Members: [{string.Join(", ", Members)}]";
  }


  class Program
  {
    static void Main()
    {
      var mongoUrl = MongoUrl.Create(@"mongodb://localhost/test");
      var client = new MongoClient(mongoUrl);
      client.DropDatabase(mongoUrl.DatabaseName);
      var database = client.GetDatabase(mongoUrl.DatabaseName);
      var collection = database.GetCollection<Group>(nameof(Group));

      var group = new Group
      {
        Name = "Class A1",
        Members = new List<Person>
        {
          new Person { Name ="Lea", Gender = 'F' }
        }
      };
      collection.InsertOne(group);
      var result = collection.Find(g => g.Members.Any(p => p.Gender == 'F')).FirstOrDefault();
      Console.WriteLine(result); // #1: Document added perfectly

      group.Members.AddRange(new List<Person>
      {
        new Person { Name ="Linus", Gender = 'M' },
        new Person { Name ="Julius", Gender = 'M' }
      });
      UpdateMemebrs(collection, group.Id, group.Members); // #2: Document updated perfectly

      group.Members.Add(new Person { Name = "Martin", Gender = 'M' });

      // #3.1: Updating members using reflection to get property value...
      var propertyInfo = typeof(Group).GetProperty("Members");
      UpdateMemebrs(collection, group.Id, propertyInfo.GetValue(group)); // NOTE: the "Members" field is actually of type List<Person> but we are parsing <object>
      // #3.2: ...will "change" the document so find does not work

      Console.ReadLine();
    }


    private static void UpdateMemebrs<TProp>(IMongoCollection<Group> collection, ObjectId groupId, TProp members)
    {
      var filter = Builders<Group>.Filter.Eq(p => p.Id, groupId);
      var update = Builders<Group>.Update.Set(nameof(Group.Members), members);
      Console.WriteLine(update.Render(BsonSerializer.LookupSerializer<Group>(), BsonSerializer.SerializerRegistry));
      collection.UpdateOne(filter, update);

      // Now, test that the update was good
      var result = collection.Find(g => g.Members.Any(p => p.Gender == 'F')).FirstOrDefault();
      Console.WriteLine(result?.ToString() ?? "Not Found");
    }
  }
}
}