using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Net.Sockets;
using System.Data;
using System.Data.OleDb;
using System.Threading;
using System.Xml;
    
namespace TestServer
{
    class Program
    {
        static void Main(string[] args)
        {
          //  string xml = "<action><command>upload</command><path>/</path><name>lol.txt</name><data>YWFh</data></action>";
          //  Console.WriteLine(XmlParse(xml));
          //  System.Console.ReadKey();
            
            IPEndPoint serverep = new IPEndPoint(IPAddress.Any, 9050);
            
            Socket server = new Socket(
                AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp
                );
            
            server.Bind(serverep);
            server.Listen(10);

            Console.WriteLine("Server has successfully started.");

            while (true)
            {
              //  Socket client = server.Accept();
                // Waits for clients
                Socket client = server.Accept();
                Thread clientThread = new Thread(delegate() {
                    ClientThread(client);
                });
                clientThread.Start();
            
            }

           // server.Close();
          
        }

        public static string XmlParse(string xml)
        {
            string response = "";
            XmlDocument doc = new XmlDocument();
            doc.LoadXml(xml);
            

            string command = doc.SelectSingleNode("action/command").InnerText;
            string path = doc.SelectSingleNode("action/path").InnerText;
            if (command == "showDir")
            {
                OleDbConnection conn = null;
                OleDbDataReader dbReader = null;
                conn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0; User Id=; Password=; Data Source=files.mdb");
                conn.Open();

                OleDbCommand query = conn.CreateCommand();
                query.CommandText = "SELECT name FROM files WHERE path=\"" + 
                    path + "\"";
                dbReader = query.ExecuteReader();

                // <?xml ... ?>
                doc = new XmlDocument();
                XmlNode docNode = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
                doc.AppendChild(docNode);

                XmlNode actionNode = doc.CreateElement("files");
                doc.AppendChild(actionNode);

                while (dbReader.Read())
                {
                    XmlNode commandNode = doc.CreateElement("file");
                    commandNode.InnerText = dbReader.GetString(0);
                    actionNode.AppendChild(commandNode);
                }

                conn.Close();

                response = doc.OuterXml;
            } else if (command == "task")
            {
                OleDbConnection conn = null;
                OleDbDataReader dbReader = null;
                conn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0; User Id=; Password=; Data Source=files.mdb");
                conn.Open();

                OleDbCommand query = conn.CreateCommand();
                query.CommandText = "SELECT path+name FROM files WHERE name LIKE '" + 
                    path + "%'";
                dbReader = query.ExecuteReader();

                // <?xml ... ?>
                doc = new XmlDocument();
                XmlNode docNode = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
                doc.AppendChild(docNode);

                XmlNode actionNode = doc.CreateElement("files");
                doc.AppendChild(actionNode);

                while (dbReader.Read())
                {
                    XmlNode commandNode = doc.CreateElement("file");
                    commandNode.InnerText = dbReader.GetString(0);
                    actionNode.AppendChild(commandNode);
                }

                conn.Close();

                response = doc.OuterXml;
            } else if (command == "remove")
            {
                OleDbConnection conn = null;
                conn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0; User Id=; Password=; Data Source=files.mdb");
                conn.Open();
                string name = doc.SelectSingleNode("action/name").InnerText;
                OleDbCommand query = conn.CreateCommand();
                if (name.Contains('/')) {
                    query.CommandText = "DELETE FROM files WHERE path like '" + path + name + "%';";
                    query.ExecuteNonQuery();
                }
                query.CommandText = "DELETE FROM files WHERE path='" + path + "' AND name='"+ name +"';";
                query.ExecuteNonQuery();
                conn.Close();

                response = "ok";
            }
            else if (command == "addDir")
            {
                OleDbConnection conn = null;
                conn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0; User Id=; Password=; Data Source=files.mdb");
                conn.Open();
                string name = doc.SelectSingleNode("action/name").InnerText;
                OleDbCommand query;
                query = conn.CreateCommand();
                query.CommandText = "SELECT count(*) FROM files WHERE name='" + name +
                    "' and path='" + path + "'";
                if ((int) query.ExecuteScalar() == 0)
                {
                    query = conn.CreateCommand();
                    query.CommandText = "INSERT INTO files (name, path)" +
                        " VALUES(\'" + name + "\', \'" + path + "\')";
                    query.ExecuteNonQuery();

                }
                else
                {
                    return "false";
                }
                conn.Close();

                response = "ok";
            }
            else if (command == "download")
            {
                OleDbConnection conn = null;
                conn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0; User Id=; Password=; Data Source=files.mdb");
                conn.Open();
                OleDbCommand query = conn.CreateCommand();
                string name = doc.SelectSingleNode("action/name").InnerText;
                query.CommandText = "SELECT data FROM files " + 
                    "WHERE path='" + path + "' and name='"+ name +"';";
                byte[] data = (byte[]) query.ExecuteScalar();
                conn.Close();
                
                // <?xml ... ?>
                doc = new XmlDocument();
                XmlNode docNode = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
                doc.AppendChild(docNode);

                XmlNode actionNode = doc.CreateElement("file");
                doc.AppendChild(actionNode);

                XmlNode dataNode = doc.CreateElement("data");
                dataNode.InnerText = Convert.ToBase64String(data);
                actionNode.AppendChild(dataNode);

                response = doc.OuterXml;
            }
            else if (command == "    ")
            {
                // Console.WriteLine(xml);
                OleDbConnection conn = null;
                conn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0; User Id=; Password=; Data Source=files.mdb");
                conn.Open();
                string name = doc.SelectSingleNode("action/name").InnerText;
                string dat = doc.SelectSingleNode("action/data").InnerText;
                string query = "INSERT INTO files (name, path, data)" +
                    " VALUES(@name, @path, @data)";
                OleDbCommand command2 = new OleDbCommand(query, conn);

                byte[] arr = Convert.FromBase64String(dat);
                command2.Parameters.Add("@name", OleDbType.Char).Value = name;
                command2.Parameters.Add("@path", OleDbType.Char).Value = path;
                command2.Parameters.Add("@data", OleDbType.VarBinary, arr.Length);
                command2.Parameters["@data"].Value = arr;
                command2.ExecuteNonQuery();
                conn.Close();

                response = "ok";
            }
            else if (command == "rename")
            {
                Console.WriteLine(doc.OuterXml);
                OleDbConnection conn = null;
                conn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0; User Id=; Password=; Data Source=files.mdb");
                conn.Open();
                string name = doc.SelectSingleNode("action/name").InnerText;
                string newname = doc.SelectSingleNode("action/newname").InnerText;
                OleDbCommand query = conn.CreateCommand();
                
                query.CommandText = "UPDATE files SET name='"+newname+"' WHERE path='" + path + "' AND name='" + name + "';";
                Console.WriteLine(query.CommandText);
                query.ExecuteNonQuery();
                conn.Close();

                response = "ok";
            }
            return response;
        }

        public static void ClientThread(Socket client)
        {
            byte[] data = new byte[1024 * 1024]; // 1mb
            int datalen;
            IPEndPoint clientep = (IPEndPoint)client.RemoteEndPoint;

            Console.WriteLine("Connected with {0} at port {1}", clientep.Address,
                   clientep.Port);

            while (true)
            {
                try
                {
                    datalen = client.Receive(data);


                    client.Send(Encoding.UTF8.GetBytes(
                        XmlParse(Encoding.UTF8.GetString(data, 0, datalen))
                        ));

                    Console.WriteLine(Encoding.UTF8.GetString(data, 0, datalen));
                }
                catch
                {
                    Console.WriteLine("Disconnected from {0}", clientep.Address);
                    return;
                }
            }
                
        }
    }
}

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Net;
using System.Net.Sockets;
using System.Xml;
using System.IO;

namespace Lab3Client
{
    public partial class Form1 : Form
    {
        // data
        Socket serverSocket;
        IPEndPoint ipepServer;
        bool isConnected = false;
        byte[] data = new byte[1024 * 1024];

        public Form1()
        {
            InitializeComponent();
        }

        private void buttonConnect_Click(object sender, EventArgs e)
        {
            string port = inputPort.Text;
            string hostname = inputHostname.Text;
            if (isConnected)
            {
                try
                {
                    serverSocket.Close();
                    isConnected = false;
                    buttonConnect.Text = "Connect";
                    label3.Visible = false;
                    path.Visible = false;
                    ShowDirectory("clear");
                } 
                catch
                {
                    MessageBox.Show(
                        "Can not close connection",
                        "Error");
                }
            }
            else
            {
                try
                {

                    ipepServer = new IPEndPoint(
                        IPAddress.Parse(hostname), Int32.Parse(port));

                    serverSocket = new Socket(AddressFamily.InterNetwork,
                        SocketType.Stream, ProtocolType.Tcp);

                    serverSocket.Connect(ipepServer);

                    isConnected = true;

                    buttonConnect.Text = "Disconnect";

                    label3.Visible = true;
                    path.Visible = true;
                    ShowDirectory("/");
                }
                catch
                {
                    MessageBox.Show(
                        "Can not connect to server " + hostname + ":" + port,
                        "Error");
                }
            }
        }

        private void Form1_FormClosed(object sender, FormClosedEventArgs e)
        {
            if (isConnected)
            {
                serverSocket.Close();
            }
        }

        public void ShowDirectory(string dirPath)
        {
            if (dirPath == "clear")
            {
                fileList.Items.Clear();
                return;
            }
            if (!isConnected)
            {
                MessageBox.Show("Client isn't connected to server", "Error");
                return;
            }

            // <?xml ... ?>
            XmlDocument doc = new XmlDocument();
            XmlNode docNode = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
            doc.AppendChild(docNode);

            XmlNode actionNode = doc.CreateElement("action");
            doc.AppendChild(actionNode);

            XmlNode commandNode = doc.CreateElement("command");
            commandNode.InnerText = "showDir";
            actionNode.AppendChild(commandNode);

            XmlNode pathNode = doc.CreateElement("path");
            pathNode.InnerText = dirPath;
            actionNode.AppendChild(pathNode);
            path.Text = dirPath;

            serverSocket.Send(Encoding.UTF8.GetBytes(doc.OuterXml));

            int datalen = serverSocket.Receive(data);
            string str = Encoding.UTF8.GetString(data, 0, datalen);
           
            if (str == "error")
            {
                MessageBox.Show("Server unknown error", "Error");
                return;
            }
            try
            {
                doc.LoadXml(str);

                XmlNodeList list = doc.SelectNodes("files/file");
                fileList.Items.Clear();


                if (path.Text != "/")
                {
                    fileList.Items.Add("../");
                }

                foreach (XmlNode node in list)
                {
                    fileList.Items.Add(node.InnerText);
                }
            }
            catch
            {
                MessageBox.Show("Server unknown error", "Error");
                return;
            }
        }

        private void buttonAddDirectory_Click(object sender, EventArgs e)
        {
            if (!isConnected)
            {
                MessageBox.Show("Client isn't connected to server", "Error");
                return;
            }

            // <?xml ... ?>
            XmlDocument doc = new XmlDocument();
            XmlNode docNode = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
            doc.AppendChild(docNode);

            XmlNode actionNode = doc.CreateElement("action");
            doc.AppendChild(actionNode);

            XmlNode commandNode = doc.CreateElement("command");
            commandNode.InnerText = "addDir";
            actionNode.AppendChild(commandNode);

            XmlNode pathNode = doc.CreateElement("path");
            pathNode.InnerText = path.Text;
            actionNode.AppendChild(pathNode);

            XmlNode nameNode = doc.CreateElement("name");
            string name = "New folder";
            DialogResult res = InputBox("New folder", "Please, input new folder name", ref name);
            if (res != DialogResult.OK)
            {
                return;
            }
            nameNode.InnerText = name + "/";
            actionNode.AppendChild(nameNode);

            serverSocket.Send(Encoding.UTF8.GetBytes(doc.OuterXml));
           
            int datalen = serverSocket.Receive(data);

            if (Encoding.UTF8.GetString(data, 0, datalen) == "error")
            {
                MessageBox.Show("Server unknown error", "Error");
                return;
            }
            if (Encoding.UTF8.GetString(data, 0, datalen) == "false")
            {
                MessageBox.Show("Folder already exists", "Error");
                return;
            }

            ShowDirectory(path.Text);

        }

        private void buttonRename_Click(object sender, EventArgs e)
        {
            if (!isConnected)
            {
                MessageBox.Show("Client isn't connected to server", "Error");
                return;
            }

            if (fileList.SelectedIndex == -1)
            {
                MessageBox.Show("Please, Choose file or folder", "Error");
                return;
            }

            // <?xml ... ?>
            XmlDocument doc = new XmlDocument();
            XmlNode docNode = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
            doc.AppendChild(docNode);

            XmlNode actionNode = doc.CreateElement("action");
            doc.AppendChild(actionNode);

            XmlNode commandNode = doc.CreateElement("command");
            commandNode.InnerText = "rename";
            actionNode.AppendChild(commandNode);

            XmlNode pathNode = doc.CreateElement("path");
            pathNode.InnerText = path.Text;
            actionNode.AppendChild(pathNode);

            XmlNode nameNode = doc.CreateElement("name");
            string name = (string) fileList.SelectedItem;
            nameNode.InnerText = name;
            actionNode.AppendChild(nameNode);

            XmlNode newnameNode = doc.CreateElement("newname");
            string newname = "";
            DialogResult res = InputBox("Change name", "Please, input new name", ref newname);
            if (res != DialogResult.OK)
            {
                return;
            }
            if (name.Contains('/'))
            {
                newnameNode.InnerText = newname + "/";
            } else {
                newnameNode.InnerText = newname;
            }
            if (newname == "") {
                MessageBox.Show("Please, Input new name", "Error");
                return;                
            }
           
            actionNode.AppendChild(newnameNode);

            serverSocket.Send(Encoding.UTF8.GetBytes(doc.OuterXml));

            int datalen = serverSocket.Receive(data);

            if (Encoding.UTF8.GetString(data, 0, datalen) == "error")
            {
                MessageBox.Show("Server unknown error", "Error");
                return;
            }

            ShowDirectory(path.Text);
        }

        private void buttonRemove_Click(object sender, EventArgs e)
        {
            if (!isConnected)
            {
                MessageBox.Show("Client isn't connected to server", "Error");
                return;
            }
            
            if (fileList.SelectedIndex == -1)
            {
                MessageBox.Show("Please, Choose file or folder", "Error");
                return;
            }

            // <?xml ... ?>
            XmlDocument doc = new XmlDocument();
            XmlNode docNode = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
            doc.AppendChild(docNode);

            XmlNode actionNode = doc.CreateElement("action");
            doc.AppendChild(actionNode);

            XmlNode commandNode = doc.CreateElement("command");
            commandNode.InnerText = "remove";
            actionNode.AppendChild(commandNode);

            XmlNode pathNode = doc.CreateElement("path");
            pathNode.InnerText = path.Text;
            actionNode.AppendChild(pathNode);

            XmlNode nameNode = doc.CreateElement("name");
            string name = (string) fileList.SelectedItem;
            nameNode.InnerText = name;
            actionNode.AppendChild(nameNode);

            serverSocket.Send(Encoding.UTF8.GetBytes(doc.OuterXml));

            int datalen = serverSocket.Receive(data);

            if (Encoding.UTF8.GetString(data, 0, datalen) == "error")
            {
                MessageBox.Show("Server unknown error", "Error");
                return;
            }

            ShowDirectory(path.Text);

        }

        private void buttonUpload_Click(object sender, EventArgs e)
        {
            if (!isConnected)
            {
                MessageBox.Show("Client isn't connected to server", "Error");
                return;
            }

            // <?xml ... ?>
            XmlDocument doc = new XmlDocument();
            XmlNode docNode = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
            doc.AppendChild(docNode);

            XmlNode actionNode = doc.CreateElement("action");
            doc.AppendChild(actionNode);

            XmlNode commandNode = doc.CreateElement("command");
            commandNode.InnerText = "upload";
            actionNode.AppendChild(commandNode);

            XmlNode pathNode = doc.CreateElement("path");
            pathNode.InnerText = path.Text;
            actionNode.AppendChild(pathNode);

            OpenFileDialog dialog = new OpenFileDialog();
            if (dialog.ShowDialog() != DialogResult.OK)
            {
                return;
            }

            Stream stream = dialog.OpenFile();
            
            XmlNode nameNode = doc.CreateElement("name");
            nameNode.InnerText = dialog.FileName;
            int index = nameNode.InnerText.LastIndexOf('\\');
            nameNode.InnerText = nameNode.InnerText.Substring(index + 1);
            actionNode.AppendChild(nameNode);

            XmlNode dataNode = doc.CreateElement("data");
            data = new byte[1024 * 1024];
            int len = stream.Read(data, 0, 1024 * 1024);
            dataNode.InnerText = Convert.ToBase64String(data, 0, len);
            actionNode.AppendChild(dataNode);
            serverSocket.Send(Encoding.UTF8.GetBytes(doc.OuterXml));

            int datalen = serverSocket.Receive(data);

            if (Encoding.UTF8.GetString(data, 0, datalen) == "error")
            {
                MessageBox.Show("Server unknown error", "Error");
                return;
            }

            stream.Close();


            ShowDirectory(path.Text);
        }
     
        private void buttonDownload_Click(object sender, EventArgs e)
        {
            if (!isConnected)
            {
                MessageBox.Show("Client isn't connected to server", "Error");
                return;
            }
            if (fileList.SelectedIndex == -1)
            {
                MessageBox.Show("Please, Choose file to download", "Error");
                return;
            }

            XmlDocument doc = new XmlDocument();
            XmlNode docNode = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
            doc.AppendChild(docNode);

            XmlNode actionNode = doc.CreateElement("action");
            doc.AppendChild(actionNode);

            XmlNode commandNode = doc.CreateElement("command");
            commandNode.InnerText = "download";
            actionNode.AppendChild(commandNode);

            XmlNode pathNode = doc.CreateElement("path");
            pathNode.InnerText = path.Text;
            actionNode.AppendChild(pathNode);

            XmlNode nameNode = doc.CreateElement("name");
            nameNode.InnerText = (string) fileList.SelectedItem;
            actionNode.AppendChild(nameNode);

            serverSocket.Send(Encoding.UTF8.GetBytes(doc.OuterXml));

            int datalen = serverSocket.Receive(data);

            if (Encoding.UTF8.GetString(data, 0, datalen) == "error")
            {
                MessageBox.Show("Server unknown error", "Error");
                return;
            }

            SaveFileDialog dialog = new SaveFileDialog();
            dialog.FileName = (string) fileList.SelectedItem;
            if (dialog.ShowDialog() != DialogResult.OK)
            {
                return;
            }

            doc.LoadXml(Encoding.UTF8.GetString(data, 0, datalen));
            byte[] convertdata = Convert.FromBase64String(doc.SelectSingleNode("file/data").InnerText);
            
           
            Stream s = dialog.OpenFile();
            s.Write(convertdata, 0, convertdata.Length);
            s.Close();

            ShowDirectory(path.Text);
        }

        private void fileList_SelectedIndexChanged(object sender, EventArgs e)
        {

        }

        public static DialogResult InputBox(string title, string promptText, ref string value)
        {
            Form form = new Form();
            Label label = new Label();
            TextBox textBox = new TextBox();
            Button buttonOk = new Button();
            Button buttonCancel = new Button();

            form.Text = title;
            label.Text = promptText;
            textBox.Text = value;

            buttonOk.Text = "OK";
            buttonCancel.Text = "Cancel";
            buttonOk.DialogResult = DialogResult.OK;
            buttonCancel.DialogResult = DialogResult.Cancel;

            label.SetBounds(9, 20, 372, 13);
            textBox.SetBounds(12, 36, 372, 20);
            buttonOk.SetBounds(228, 72, 75, 23);
            buttonCancel.SetBounds(309, 72, 75, 23);

            label.AutoSize = true;
            textBox.Anchor = textBox.Anchor | AnchorStyles.Right;
            buttonOk.Anchor = AnchorStyles.Bottom | AnchorStyles.Right;
            buttonCancel.Anchor = AnchorStyles.Bottom | AnchorStyles.Right;

            form.ClientSize = new Size(396, 107);
            form.Controls.AddRange(new Control[] { label, textBox, buttonOk, buttonCancel });
            form.ClientSize = new Size(Math.Max(300, label.Right + 10), form.ClientSize.Height);
            form.FormBorderStyle = FormBorderStyle.FixedDialog;
            form.StartPosition = FormStartPosition.CenterScreen;
            form.MinimizeBox = false;
            form.MaximizeBox = false;
            form.AcceptButton = buttonOk;
            form.CancelButton = buttonCancel;

            DialogResult dialogResult = form.ShowDialog();
            value = textBox.Text;
            return dialogResult;
        }

        private void fileList_MouseDoubleClick(object sender, MouseEventArgs e)
        {
            if (fileList.SelectedIndex == -1)
            {
                return;
            }
            string item = fileList.SelectedItem.ToString();
            
            // check - is folder?
            if (item.Contains('/'))
            {
                // folder
                if (item == "../")
                {
                    string subpath = path.Text.Substring(0, path.Text.Length - 1);
                    int pos = subpath.LastIndexOf('/') + 1;
                    ShowDirectory(subpath.Substring(0, pos));
                }
                else
                {
                    ShowDirectory(path.Text + item);
                }
            }
            else
            {
                buttonDownload_Click(sender, e);
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (!isConnected)
            {
                MessageBox.Show("Client isn't connected to server", "Error");
                return;
            }

            // <?xml ... ?>
            XmlDocument doc = new XmlDocument();
            XmlNode docNode = doc.CreateXmlDeclaration("1.0", "UTF-8", null);
            doc.AppendChild(docNode);

            XmlNode actionNode = doc.CreateElement("action");
            doc.AppendChild(actionNode);

            XmlNode commandNode = doc.CreateElement("command");
            commandNode.InnerText = "task";
            actionNode.AppendChild(commandNode);

            string tmpstr = "n";
            XmlNode startNode = doc.CreateElement("path");
            if (DialogResult.OK != InputBox("InputBox","Input beginnig of file", ref tmpstr)) {
                return;
            }
            startNode.InnerText = tmpstr;
            actionNode.AppendChild(startNode);

            serverSocket.Send(Encoding.UTF8.GetBytes(doc.OuterXml));

            int datalen = serverSocket.Receive(data);
            string str = Encoding.UTF8.GetString(data, 0, datalen);

            if (str == "error")
            {
                MessageBox.Show("Server unknown error", "Error");
                return;
            }
            try
            {
                doc.LoadXml(str);

                XmlNodeList list = doc.SelectNodes("files/file");

                StringBuilder builder = new StringBuilder();
                foreach (XmlNode node in list)
                {
                    builder.Append(node.InnerText);
                    builder.Append("\n");
                }
                MessageBox.Show(builder.ToString(), "Results");
            }
            catch
            {
                MessageBox.Show("Server unknown error", "Error");
                return;
            }
        }
        
    }
}