using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Nexi
{
    public class NodeBase
    {
        public delegate void MessageHandler(Message msg);
        public event MessageHandler OnMessageReceived;

        private class EndPointRecord
        {
            public EndPointRecord(EndPoint ep, double initialWeight)
            {
                EndPoint = ep;
                Weight = initialWeight;
            }

            public readonly EndPoint EndPoint;
            public string NodeId { get { return EndPoint.NodeId; } }

            public double Weight;
        }

        List<EndPoint> _peers = new List<EndPoint>();
        Dictionary<string, EndPointRecord> _incomingPeers = new Dictionary<string, EndPointRecord>();

        public readonly string Id;

        public NodeBase(string id)
        {
            _endPoint = new EndPoint(this);
            Id = id;
        }

        public void PleaseIntroduce(EndPoint ep)
        {
            if (!_peers.Contains(ep.NodeId))
                _peers.Add(ep);

            if (!_incomingPeers.ContainsKey(ep.NodeId))
                _incomingPeers.Add(ep.NodeId, new EndPointRecord(ep, 0.5));
        }

        private EndPoint _endPoint;
        public EndPoint EndPoint { get { return _endPoint; } }

        internal void Receive(Message msg)
        {
            if (seenMessage(msg))
            {
                return;
            }

            processMessage(msg);
        }

        private void processMessage(Message msg)
        {
            MessageHandler handler = OnMessageReceived;
            if (handler != null)
            {
                handler(msg);
            }

            // XXX should do this with a new message,
            // only if we've done anything.
            //broadcastMessage(msg);
        }

        private void broadcastMessage(Message msg)
        {
            foreach (var peer in _peers)
            {
                peer.Receive(this.EndPoint, msg);
            }
        }

        private bool seenMessage(Message msg)
        {
            return false; // XXX
        }
    }
}