using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using MongoDB.Bson;
using MongoDB.Driver;
using Serilog;
using Landmark.OLA.Application.Common.Domain;


namespace Landmark.OLA.Application.DataAccess
{
    public class ConfigurationAccess : IDisposable, IConfigurationAccess
    {
        private bool disposed = false;
        private readonly IDataClient _client;
        private readonly string _collectionName = "AppConfiguration";

        public ConfigurationAccess(
            IDataClient dataClient)
        {
            _client = dataClient;
        }

        private IMongoCollection<StoredSettings> GetConfigurationContainersCollection()
        {
            return _client.GetDatabase().GetCollection<StoredSettings>(_collectionName);
        }

        public StoredSettings GetStoredSettings()
        {
            try
            {
                var collection = GetConfigurationContainersCollection();
                var result = collection.Find(new BsonDocument()).ToList().FirstOrDefault();
                if( result == null )
                {
                    throw new Exception("Could not find app configuration.");
                }
                return result;
            }
            catch (MongoConnectionException ex)
            {
                Log.Error(ex.Message);
                throw new InvalidDataException("Could not load app configuration.");
            }
        }

        public void CreateStoredSettings(StoredSettings storedSettings)
        {
            try
            {
                var collection = GetConfigurationContainersCollection();

                if (collection.Find(new BsonDocument()).ToList().Count > 0)
                {
                    throw new Exception("Can only insert 1 configuration");
                }
                collection.InsertOne(storedSettings);
            }           
            catch (Exception e)
            {
                Log.Error(e.Message);
                throw new InvalidDataException("Error occured while creating app configuration");
            }
        }

        public void UpdateStoredSettings(StoredSettings storedSettings)
        {
            try
            {
                var collection = GetConfigurationContainersCollection();

                ReplaceOneResult result = collection.ReplaceOne(eachConfig => eachConfig.Id == storedSettings.Id, storedSettings);
                if (result.MatchedCount == 0 || result.ModifiedCount == 0)
                {
                    throw new KeyNotFoundException("Item not found");
                }
            }
            catch (KeyNotFoundException en)
            {
                Log.Error(en.Message);
                throw new KeyNotFoundException(en.Message);
            }            
            catch (Exception e)
            {
                Log.Error(e.Message);
                throw new InvalidDataException("Error occured while updating app configuration");
            }
        }
       
        #region IDisposable

        public void Dispose()
        {
            this.Dispose(true);
            GC.SuppressFinalize(this);
        }

        protected virtual void Dispose(bool disposing)
        {
            if (!this.disposed)
            {
                if (disposing)
                {
                }
            }

            this.disposed = true;
        }       

        #endregion
    }
}