using System;
using System.Collections.Generic;
using System.Linq;
using Logging;

namespace FrontendRouting
{
    public static class FeRoutingViewsFinder<TAssembly>
    {
        // ReSharper disable once StaticMemberInGenericType
        private static Dictionary<Type, FeRouteAttribute[]> _all;

        private static Dictionary<Type, FeRouteAttribute[]> FindAllAttr()
        {
            var tFerv = typeof(FeRoutingView);
            var types = typeof(TAssembly).Assembly.GetTypes().Where(p => false == p.IsAbstract && p.IsSubclassOf(tFerv));

            var all = new Dictionary<Type, FeRouteAttribute[]>();

            foreach (var type in types)
            {
                var attrs = type.GetCustomAttributes(typeof(FeRouteAttribute), false).Cast<FeRouteAttribute>().ToArray();
                if (0 == attrs.Length)
                {
                    Logger.Warn($"No route attribute for {type.FullName}");
                }
                else
                {
                    all[type] = attrs.ToArray();
                }
            }

            return all;
        }

        public static ICollection<FeRouteAttribute> AllAttributes
        {
            get
            {
                if (null == _all) _all = FindAllAttr();
                return _all.SelectMany(p => p.Value).ToArray();
            }
        }

        public static void RegisterAllView()
        {
            if (null == _all) _all = FindAllAttr();
            foreach (var kvp in _all)
            {
                var instance = (FeRoutingView)Activator.CreateInstance(kvp.Key);
                foreach (var routeAttribute in kvp.Value)
                {
                    FeRoutingManager.Register(routeAttribute.Path, instance);
                }
            }
        }
    }
}