using MongoDB.Driver;
using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using System.Reflection;
using Tango.DAL.Attributes;
using System.Linq.Expressions;
using MongoDB.Driver.Linq;

namespace Tango.DAL.Mongo
{
    public class MongoRepository<T> : IRepository<T> where T : Entity
    {
        private IMongoDatabase _database;
        private MongoClient _client;
        private IMongoCollection<T> _collection;

        public MongoRepository(MongoDataBaseSettings settings)
        {
            _client = new MongoClient(settings.Address);
            _database = _client.GetDatabase(settings.DatabaseName);
        }

        private IMongoCollection<T> GetCollection()
        {
            if (_collection == null)
            {
                _collection = _database.GetCollection<T>(typeof(T).GetCustomAttribute<MongoCollectionAttribute>().Name);
            }

            return _collection;
        }

        public async Task<List<T>> GetAllAsync()
        {
            return await (await GetCollection().FindAsync(x => true)).ToListAsync();
        }

        public async Task<List<T>> GetAsync(Expression<Func<T, bool>> filter)
        {
            return await (await GetCollection().FindAsync(filter)).ToListAsync();
        }

        public async Task<T> ReplaceAsync(T entity)
        {
            await GetCollection().ReplaceOneAsync(x => x.ID == entity.ID, entity);
            return entity;
        }

        public async Task<long> DeleteAsync(Expression<Func<T, bool>> filter)
        {
            return (await GetCollection().DeleteOneAsync(filter)).DeletedCount;
        }

        public async Task<T> Insert(T entity)
        {
            await GetCollection().InsertOneAsync(entity);
            return entity;
        }

        public Task<long> Count()
        {
            return GetCollection().CountDocumentsAsync(x => true);
        }

        public Task<long> Count(Expression<Func<T, bool>> filter)
        {
            return GetCollection().CountDocumentsAsync(filter);
        }

        public void Dispose()
        {

        }
    }
}