using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Threading.Tasks;

namespace JsonRPC4.Router
{

	public class RpcEndpointBuilder
	{
		private List<MethodInfo> baseMethods
		{
			get;
		} = new List<MethodInfo>();


		private Dictionary<RpcPath, List<MethodInfo>> methods
		{
			get;
		} = new Dictionary<RpcPath, List<MethodInfo>>();


		public RpcEndpointBuilder AddMethod(RpcPath path, MethodInfo methodInfo)
		{
			Add(path, methodInfo);
			return this;
		}

		public RpcEndpointBuilder AddControllerWithDefaultPath<T>()
		{
			Type typeFromHandle = typeof(T);
			return AddControllerWithDefaultPath(typeFromHandle);
		}

		public RpcEndpointBuilder AddControllerWithDefaultPath(Type controllerType)
		{
			RpcRouteAttribute customAttribute = controllerType.GetCustomAttribute<RpcRouteAttribute>(inherit: true);
			ReadOnlySpan<char> path = (customAttribute != null && customAttribute.RouteName != null) ? MemoryExtensions.AsSpan(customAttribute.RouteName) : ((!controllerType.Name.EndsWith("Controller")) ? MemoryExtensions.AsSpan(controllerType.Name) : MemoryExtensions.AsSpan(controllerType.Name, 0, controllerType.Name.IndexOf("Controller")));
			RpcPath path2 = RpcPath.Parse(path);
			return AddController(controllerType, path2);
		}

		public RpcEndpointBuilder AddController<T>(RpcPath path = null)
		{
			Type typeFromHandle = typeof(T);
			return AddController(typeFromHandle, path);
		}

		public RpcEndpointBuilder AddController(Type type, RpcPath path = null)
		{
			foreach (MethodInfo item in Extract(type))
			{
				Add(path, item);
			}
			return this;
		}

		public IRpcMethodProvider Resolve()
		{
			return new StaticRpcMethodProvider(baseMethods, methods);
		}

		private IEnumerable<MethodInfo> Extract(Type controllerType)
		{
			return from m in (from t in controllerType.Assembly.GetTypes()
							  where t == controllerType
							  select t).SelectMany((Type t) => t.GetMethods(BindingFlags.Instance | BindingFlags.Public))
				   where m.DeclaringType != typeof(object)
				   select m;
		}

		private void Add(RpcPath path, MethodInfo methodInfo)
		{
			List<MethodInfo> value;
			if (path == null)
			{
				value = baseMethods;
			}
			else if (!methods.TryGetValue(path, out value))
			{
				List<MethodInfo> list2 = methods[path] = new List<MethodInfo>();
				value = list2;
			}
			value.Add(methodInfo);
		}
	}
}