using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Net.Sockets;

namespace Forwarder
{
    public partial class ForwarderControl : UserControl
    {
        public ForwarderChanged WhenChanged;

        Forwarder fw = new Forwarder();

        public ForwarderControl()
        {
            InitializeComponent();
            fw.WhenMessage = FMessage;
            lvHistory_Resize(null, null);
            FMessage(fw, null);
        }

        private int FMessageIcon(ForwarderMessageType t)
        {
            switch (t)
            {
                case ForwarderMessageType.ACTIVATED:
                case ForwarderMessageType.DEACTIVATED:
                    return 0;
                case ForwarderMessageType.ERROR:
                    return 1;
                case ForwarderMessageType.TSTART:
                    return 2;
                case ForwarderMessageType.TSEND:
                    return 3;
                case ForwarderMessageType.TRECV:
                    return 4;
                case ForwarderMessageType.TEND:
                    return 5;
                default:
                    return 1;
            }
        }

        private void FMessage(Forwarder sender, ForwarderMessage msg)
        {
            if (InvokeRequired)
            {
                try
                {
                    Invoke(new MethodInvoker(() => FMessage(sender, msg)));
                }
                catch { }
                return;
            }
            ListViewItem lvi = null;
            if (msg != null)
                switch (msg.Type)
                {
                    case ForwarderMessageType.ACTIVATED:
                    case ForwarderMessageType.DEACTIVATED:
                        lvi = lvHistory.Items.Add(msg.Message);
                        lvi.ImageIndex = 0;
                        break;
                    case ForwarderMessageType.ERROR:
                        lvi = lvHistory.Items.Add(msg.Message);
                        lvi.ImageIndex = 1;
                        break;
                    case ForwarderMessageType.TSTART:
                        lvi = lvHistory.Items.Add(msg.Message);
                        lvi.ImageIndex = 2;
                        msg.Transmission.Tag = lvi;
                        lvi.SubItems.Add("0");
                        lvi.SubItems.Add("0");
                        break;
                    case ForwarderMessageType.TEND:
                    case ForwarderMessageType.TRECV:
                    case ForwarderMessageType.TSEND:
                        lvi = msg.Transmission.Tag as ListViewItem;
                        if (lvi == null)
                        {
                            lvi = lvHistory.Items.Add("<<< Lost transmission >>>");
                            lvi.ImageIndex = 1;
                            msg.Transmission.Tag = lvi;
                        }
                        else
                        {
                            lvi.ImageIndex = FMessageIcon(msg.Type);
                            lvi.SubItems[1].Text = FBytes(msg.Transmission.Uploaded);
                            lvi.SubItems[2].Text = FBytes(msg.Transmission.Downloaded);
                        }
                        break;
                    default:
                        lvi = lvHistory.Items.Add("[??] " + msg.Message);
                        lvi.ImageIndex = 1;
                        break;
                }
            if (lvi != null)
            {
                if (rbFollow.Checked)
                    lvi.Selected = true;
                //lvHistory_Resize(null, null);
            }
            lbInfo.Text = "Hints: " + sender.TotalConnections + " Alive: " + sender.CurrentConnections;
        }

        private string FBytes(int bytes)
        {
            if (bytes < 1024)
                return bytes.ToString();
            string tail = null;
            double b = bytes;
            if (b > 1024)
            {
                tail = "Kb";
                b /= 1024;
            }
            if (b > 1024)
            {
                tail = "Mb";
                b /= 1024;
            }
            if (b > 1024)
            {
                tail = "Gb";
                b /= 1024;
            }
            return b.ToString("#0.00") + tail;
        }

        private bool RefreshForwarder()
        {
            try
            {
                fw.SetLocal(cbLocal.Checked ? "127.0.0.1" : "0.0.0.0", tbSrcPort.Text);
                tbSrcPort.BackColor = SystemColors.Window;
            }
            catch (FormatException)
            {
                tbSrcPort.BackColor = Color.LightPink;
                return false;
            }
            try
            {
                fw.SetRemote(tbDestHost.Text, tbDestPort.Text);
                tbDestHost.BackColor = SystemColors.Window;
                tbDestPort.BackColor = SystemColors.Window;
            }
            catch (FormatException)
            {
                tbDestPort.BackColor = Color.LightPink;
                return false;
            }
            catch (SocketException)
            {
                tbDestHost.BackColor = Color.LightPink;
                return false;
            }
            return true;
        }

        public void StopForwarder()
        {
            fw.Deactivate();
        }

        public override string ToString()
        {
            return fw.ToString();
        }

        public string SourcePort => tbSrcPort.Text;
        public bool SourceLocal => cbLocal.Checked;
        public string DestinationPort => tbDestPort.Text;
        public string DestinationHost => tbDestHost.Text;
        public bool Active => fw.Active;

        private void btStart_Click(object sender, EventArgs e)
        {
            try
            {
                if (fw.Active)
                {
                    fw.Deactivate();
                    tbDestHost.Enabled = true;
                    tbDestPort.Enabled = true;
                    tbSrcPort.Enabled = true;
                    cbLocal.Enabled = true;
                    btStart.Text = "Start";
                }
                else
                {
                    pConf.Enabled = false;
                    if (!RefreshForwarder())
                    {
                        pConf.Enabled = true;
                        return;
                    }
                    pConf.Enabled = true;

                    fw.Activate();
                    tbDestHost.Enabled = false;
                    tbDestPort.Enabled = false;
                    tbSrcPort.Enabled = false;
                    cbLocal.Enabled = false;
                    btStart.Text = "Stop";
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, ex.GetType().Name, MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
            WhenChanged?.Invoke();
        }

        private void ConfChanged(object sender, EventArgs e)
        {
            WhenChanged?.Invoke();
        }

        private void lvHistory_Resize(object sender, EventArgs e)
        {
            //lvHistory.Columns[0].AutoResize(ColumnHeaderAutoResizeStyle.ColumnContent);
            int acw = 0;
            for (int i = 1; i < lvHistory.Columns.Count; i++)
                acw += lvHistory.Columns[i].Width;
            //if (lvHistory.Columns[0].Width + acw < lvHistory.ClientRectangle.Width)
            lvHistory.Columns[0].Width = lvHistory.ClientRectangle.Width - acw;
        }

        private void btClear_Click(object sender, EventArgs e)
        {
            lvHistory.Items.Clear();
            fw.ResetCounter();
        }
    }

    public delegate void ForwarderChanged();
}