#region Copyright
// /************************************************************************
//    Copyright (c) 2016 Jamie Rees
//    File: NotificationService.cs
//    Created By: Jamie Rees
//   
//    Permission is hereby granted, free of charge, to any person obtaining
//    a copy of this software and associated documentation files (the
//    "Software"), to deal in the Software without restriction, including
//    without limitation the rights to use, copy, modify, merge, publish,
//    distribute, sublicense, and/or sell copies of the Software, and to
//    permit persons to whom the Software is furnished to do so, subject to
//    the following conditions:
//   
//    The above copyright notice and this permission notice shall be
//    included in all copies or substantial portions of the Software.
//   
//    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
//    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
//    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
//    NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
//    LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
//    OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
//    WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//  ************************************************************************/
#endregion
using System;
using System.Collections.Concurrent;
using System.Linq;
using System.Threading.Tasks;

using NLog;

using PlexRequests.Services.Interfaces;
using PlexRequests.Core.SettingModels;

namespace PlexRequests.Services.Notification
{
    public class NotificationService : INotificationService
    {
        private static Logger Log = LogManager.GetCurrentClassLogger();
        public ConcurrentDictionary<string, INotification> Observers { get; } = new ConcurrentDictionary<string, INotification>();

        /// <summary>
        /// Sends a notification to the user. This one is used in normal notification scenarios 
        /// </summary>
        /// <param name="model">The model.</param>
        /// <returns></returns>
        public async Task Publish(NotificationModel model)
        {
            var notificationTasks = Observers.Values.Select(notification => NotifyAsync(notification, model));

            await Task.WhenAll(notificationTasks).ConfigureAwait(false);
        }

        /// <summary>
        /// Sends a notification to the user, this is usually for testing the settings.
        /// </summary>
        /// <param name="model">The model.</param>
        /// <param name="settings">The settings.</param>
        /// <returns></returns>
        public async Task Publish(NotificationModel model, Settings settings)
        {
            var notificationTasks = Observers.Values.Select(notification => NotifyAsync(notification, model, settings));

            await Task.WhenAll(notificationTasks).ConfigureAwait(false);
        }

        public void Subscribe(INotification notification)
        {
            Observers.TryAdd(notification.NotificationName, notification);
        }

        public void UnSubscribe(INotification notification)
        {
            Observers.TryRemove(notification.NotificationName, out notification);
        }

        private static async Task NotifyAsync(INotification notification, NotificationModel model)
        {
            try
            {
                await notification.NotifyAsync(model).ConfigureAwait(false);
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Notification '{notification.NotificationName}' failed with exception");
            }

        }

        private static async Task NotifyAsync(INotification notification, NotificationModel model, Settings settings)
        {
            try
            {
                await notification.NotifyAsync(model, settings).ConfigureAwait(false);
            }
            catch (Exception ex)
            {
                Log.Error(ex, $"Notification '{notification.NotificationName}' failed with exception");
            }
        }
    }
}