using System;
using System.Collections.Generic;
using System.Linq;
using Artemis.Core.LayerBrushes;

namespace Artemis.Core
{
    internal class LayerBrushStore
    {
        private static readonly List<LayerBrushRegistration> Registrations = new List<LayerBrushRegistration>();

        public static LayerBrushRegistration Add(LayerBrushDescriptor descriptor)
        {
            LayerBrushRegistration registration;
            lock (Registrations)
            {
                if (Registrations.Any(r => r.LayerBrushDescriptor == descriptor))
                    throw new ArtemisCoreException($"Store already contains layer brush '{descriptor.DisplayName}'");

                registration = new LayerBrushRegistration(descriptor, descriptor.LayerBrushProvider.PluginInfo.Plugin) {IsInStore = true};
                Registrations.Add(registration);
            }

            OnLayerBrushAdded(new LayerBrushStoreEvent(registration));
            return registration;
        }

        public static void Remove(LayerBrushRegistration registration)
        {
            lock (Registrations)
            {
                if (!Registrations.Contains(registration))
                    throw new ArtemisCoreException($"Store does not contain layer brush '{registration.LayerBrushDescriptor.DisplayName}'");

                Registrations.Remove(registration);
                registration.IsInStore = false;
            }

            OnLayerBrushRemoved(new LayerBrushStoreEvent(registration));
        }

        public static List<LayerBrushRegistration> GetAll()
        {
            lock (Registrations)
            {
                return new List<LayerBrushRegistration>(Registrations);
            }
        }

        public static LayerBrushRegistration Get(Guid pluginGuid, string typeName)
        {
            lock (Registrations)
            {
                return Registrations.FirstOrDefault(d => d.PluginImplementation.PluginInfo.Guid == pluginGuid &&
                                                         d.LayerBrushDescriptor.LayerBrushType.Name == typeName);
            }
        }

        #region Events

        public static event EventHandler<LayerBrushStoreEvent> LayerBrushAdded;
        public static event EventHandler<LayerBrushStoreEvent> LayerBrushRemoved;

        private static void OnLayerBrushAdded(LayerBrushStoreEvent e)
        {
            LayerBrushAdded?.Invoke(null, e);
        }

        private static void OnLayerBrushRemoved(LayerBrushStoreEvent e)
        {
            LayerBrushRemoved?.Invoke(null, e);
        }

        #endregion
    }
}