using System;
using System.Collections.Generic;
using System.Collections;
using System.Security;
using ln.types;
using System.Linq;
using System.Threading;
using ln.skyscanner.crawl;
using ln.snmp.rfc1213;
using ln.types.odb;
using ln.types.sync;
using ln.logging;
using System.Globalization;
using ln.types.threads;
using ln.types.odb.values;

namespace ln.skyscanner.entities
{
    public class GlobalNetwork : Persistent
    {
        [Unsynced]
        public SkyScanner SkyScanner => SkyScanner.Instance;
        [Unsynced]
        public SkyEntities SkyEntities { get; private set; }

        public IEnumerable<Subnet> Subnets => SkyEntities.subnetCollection;
        public IEnumerable<Node> Nodes => SkyEntities.nodeCollection;

        public HopMap DefaultHopMap { get; private set; } = new HopMap();

        private object _updateLock = new object();

        public GlobalNetwork()
        {
        }

        public GlobalNetwork(SkyEntities skyEntities)
        {
            SkyEntities = skyEntities;
        }

        public void EnsureSubnet(CIDR network)
        {
            SkyScanner.Crawler.EnsureSubnet(network);

            Subnet subnet = SkyEntities.subnetCollection.Where(s => s.Network.Equals(network)).FirstOrDefault();
            if (subnet == null)
            {
                subnet = new Subnet(network);
                SkyEntities.subnetCollection.Upsert(subnet);
            }

        }

        public Node GetNode(Guid id)
        {
            return SkyEntities.nodeCollection.Select(id);
        }

        public Subnet FindSubnetForHost(CIDR host)
        {
            return SkyEntities.subnetCollection.Select(net => net.Network.Contains(host)).FirstOrDefault();
        }

        public IEnumerable<Node> FindHostsInSubnet(CIDR network)
        {
            IntfIP[] intfIPs = SkyEntities.intfIPCollection.Select((ip) => ip.IP.In(network)).ToArray();
            NetworkInterface[] networkInterfaces = intfIPs.Select((iip) => iip.NetworkInterface).Distinct().ToArray();
            Node[] nodes = SkyEntities.nodeCollection.Select(networkInterfaces.Select((ni) => (ODBValue)ni.NodeID).Distinct()).ToArray();
            return nodes;
        }

        public IEnumerable<Node> FindNeighbors(Node node)
        {
            return node.IPAdresses.SelectMany((ip) => Timing.Meassure("FindHostsInSubnet", () => FindHostsInSubnet(ip)).Distinct().ToArray());
        }

        public Node FindNodeByIP(IEnumerable<CIDR> ips)
        {
            foreach (CIDR ip in ips)
            {
                Node node = FindNodeByIP(ip);
                if (node != null)
                    return node;
            }
            return null;
        }
        public Node FindNodeByIP(CIDR ip)
        {
            ip = ip.Host;

            IntfIP _iip = SkyEntities.intfIPCollection.Where((iip) => iip.IP.Host.Equals(ip)).FirstOrDefault();
            return _iip?.NetworkInterface?.Node;
        }

        [Unsynced]
        private Queue<CrawledHost> updateQueue = new Queue<CrawledHost>();

        public void EnqueueUpdate(CrawledHost crawledHost)
        {
            lock (updateQueue)
            {
                if (!updateQueue.Contains(crawledHost))
                    updateQueue.Enqueue(crawledHost);
            }
        }

        public void Update()
        {
            lock (updateQueue)
            {
                if (updateQueue.Count == 0)
                    return;
            }
            while (true)
            {
                CrawledHost crawledHost = null;
                lock (updateQueue)
                {
                    if (updateQueue.Count > 0)
                        crawledHost = updateQueue.Dequeue();
                    else
                        break;
                }

                Update(crawledHost);
            }

            //SkyScanner.Entities.DBGlobalNetwork.SavePersistent(SkyScanner.Entities.DBGlobalNetwork.Root);
        }

        private void Update(CrawledHost crawledHost)
        {
            Logging.Log(LogLevel.DEBUG, "Entity: update {0}", crawledHost.PrimaryIP);

            Node node = FindNodeByIP(crawledHost.PrimaryIP);
            if (node == null)
                node = FindNodeByIP(crawledHost.IPAddresses);

            if (node == null)
            {
                node = new Node(crawledHost.PrimaryIP);
                node.Name = crawledHost.Name;
                node.PrimaryMac = crawledHost.PrimaryHWAddr;
            }

            foreach (String si in crawledHost.GetHint<string[]>("rfc1213.interfaces",new string[0]))
            {
                String[] fields = si.Split(';');

                NetworkInterface networkInterface = node.GetInterface(fields[0]);
                if (networkInterface == null)
                    networkInterface = new NetworkInterface(node, fields[0]);

                networkInterface.HWAddress = fields[1];

                SkyEntities.interfaceCollection.Upsert(networkInterface);

                CIDR[] crawledIPs = fields[2].Split(',').Where((sip) => !String.Empty.Equals(sip)).Select((sip) => CIDR.Parse(sip)).ToArray();
                IntfIP[] currentIPs = networkInterface.IPs.ToArray();

                foreach (CIDR crawledIP in crawledIPs)
                {
                    int n;
                    for (n=0; n < currentIPs.Length; n++)
                        if (currentIPs[n].IP.Equals(crawledIP))
                            break;
                    if (n == currentIPs.Length)
                    {
                        IntfIP miss = new IntfIP(networkInterface, crawledIP);
                        SkyEntities.intfIPCollection.Upsert(miss);
                    }
                }

                foreach (IntfIP iip in currentIPs)
                {
                    CIDR ip = iip.IP;

                    if (crawledIPs.Contains(ip))
                    {
                        EnsureSubnet(ip.Network);
                    }
                    else
                    {
                        SkyEntities.intfIPCollection.Delete(iip);
                    }
                }
            }

            node.RemoveURI("ssh");
            if (crawledHost.GetHint<int>("ssh.port", -1) != -1)
            {
                node.AddURI(
                    new URI(
                        String.Format("ssh://{0}:{1}@{2}:{3}",
                            crawledHost.GetHint<string>("ssh.login"),
                            crawledHost.GetHint<string>("ssh.password"),
                            crawledHost.GetHint<CIDR>("ssh.ip"),
                            crawledHost.GetHint<int>("ssh.port")
                            )
                        )
                    );
            }


            node.LastUpdate = DateTime.Now;
            SkyEntities.nodeCollection.Upsert(node);
        }
    }
}