using ForumContracts.BindingModels;
using ForumContracts.SearchModels;
using ForumContracts.StorageContracts;
using ForumContracts.ViewModels;
using ForumDatabaseImplement.Models;
using MongoDB.Bson;
using MongoDB.Driver;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ForumMongoDataBase.Implements
{
	public class QuestionStorage : IQuestionStorage
	{
		public MongoClient context;
		private readonly IMongoCollection<Question> _collection;

		public QuestionStorage()
		{
			context = ForumMongoDataBase.getInstance().client;
			_collection = context.GetDatabase("forum").GetCollection<Question>("questions");
		}

		public QuestionViewModel? Delete(QuestionBindingModel model)
		{
			var filter = Builders<Question>.Filter.Eq(q => q.Id, model.Id);
			var question = _collection.FindOneAndDelete(filter);

			if (question == null)
			{
				return null;
			}

			return question.GetViewModel();
		}

		public QuestionViewModel? GetElement(QuestionSearchModel model)
		{
			if (!model.Id.HasValue)
			{
				return null;
			}

			var question = _collection.Find(q => q.Id == model.Id.Value)
									   .FirstOrDefault();

			if (question == null)
			{
				return null;
			}

			return question.GetViewModel();
		}

		public List<QuestionViewModel> GetFilteredList(QuestionSearchModel model)
		{
			var filter = Builders<Question>.Filter.Empty;

			if (model.Id.HasValue)
			{
				filter &= Builders<Question>.Filter.Eq(q => q.Id, model.Id.Value);
			}

			if (model.CategoryId.HasValue)
			{
				filter &= Builders<Question>.Filter.Eq(q => q.CategoryId, model.CategoryId.Value);
			}

			if (model.UserId.HasValue)
			{
				filter &= Builders<Question>.Filter.Eq(q => q.UserId, model.UserId.Value);
			}

			var questions = _collection.Find(filter)
									   .ToList()
									   .Select(q => q.GetViewModel())
									   .ToList();

			return questions;
		}

		public List<QuestionViewModel> HardRequest(QuestionSearchModel model)
		{
			var filter = Builders<Question>.Filter.And(
							Builders<Question>.Filter.Gte(q => q.CreateDate, model.DateFrom),
							Builders<Question>.Filter.Lte(q => q.CreateDate, model.DateTo));

			var questions = _collection.Find(filter)
									   .SortBy(q => q.CreateDate)
									   .ToList()
									   .Select(q => q.GetViewModel())
									   .ToList();

			return questions;
		}

		public List<QuestionViewModel> GetFullList()
		{
			var questions = _collection.Find(_ => true)
									   .ToList()
									   .Select(q => q.GetViewModel())
									   .ToList();

			return questions;
		}

		public QuestionViewModel? Insert(QuestionBindingModel model)
		{
			var question = Question.Create(model);

			if (question == null)
			{
				return null;
			}

			_collection.InsertOne(question);

			return question.GetViewModel();
		}

		public QuestionViewModel? Update(QuestionBindingModel model)
		{
			var filter = Builders<Question>.Filter.Eq(q => q.Id, model.Id);
			var question = _collection.Find(filter).FirstOrDefault();

			if (question == null)
			{
				return null;
			}

			question.Update(model);
			_collection.ReplaceOne(filter, question);

			return question.GetViewModel();
		}
	}
}