using System;
using System.IO;
using System.Drawing;
// Security Change (added using statements)
using System.Security;
using System.Security.Permissions;
using System.Windows.Forms;
using System.ComponentModel;

class App{
   public static void Main(){
      Application.Run(new Pad());
   }
}

public class Pad : System.Windows.Forms.Form{
   System.Windows.Forms.TextBox text;
   System.Windows.Forms.MainMenu mainMenu;   
   System.Windows.Forms.MenuItem menuFile;
   System.Windows.Forms.MenuItem menuFileSave;   
   System.Windows.Forms.MenuItem menuFileNew;
   System.Windows.Forms.MenuItem menuFileOpen;
   System.Windows.Forms.MenuItem menuFileSaveAs;
   System.Windows.Forms.MenuItem menuFileExit;
   System.Windows.Forms.MenuItem menuEdit;
   System.Windows.Forms.MenuItem menuEditUndo;
   System.Windows.Forms.MenuItem menuEditCut;
   System.Windows.Forms.MenuItem menuEditCopy;
   System.Windows.Forms.MenuItem menuEditPaste;
   System.Windows.Forms.MenuItem menuEditDelete;
   System.Windows.Forms.MenuItem menuEditSelectAll;
   System.Windows.Forms.MenuItem menuFormat;
   System.Windows.Forms.MenuItem menuFormatWordWrap;
   System.Windows.Forms.MenuItem menuFormatFont;   
   System.Windows.Forms.MenuItem menuBar1;
   System.Windows.Forms.MenuItem menuBar2;
   System.Windows.Forms.MenuItem menuBar3;
   System.Windows.Forms.StatusBar status;

   // Keep track of the file name and whether or not the data has changed
   String fileName;   
   Boolean isDirty;      

   public Pad(){      
      // Setup the controls, and setup a handler for the Format menu's popup
      InitializeComponent();              
      menuFormat.Popup += new EventHandler(menuFormat_Popup);            
      ResetForm();
      // Security Change INTERNET ZONE
      // Added a try catch and a demand for clipboard access
      // if exception is thrown, then the paste menu is disabled
      try{         
         UIPermission perm = 
            new UIPermission(UIPermissionClipboard.AllClipboard);
         perm.Demand();
      }catch(SecurityException){
         menuEditPaste.Enabled = false;
      }      
   }   
   
   void menuFileNew_Click(object sender, System.EventArgs e){
      Boolean cancel;
      CheckToSave(out cancel);
      if(!cancel){
         ResetForm();     
      }
   }

   void menuFileOpen_Click(object sender, System.EventArgs e){
      OpenFile();
   }

   void menuFileSave_Click(object sender, System.EventArgs e){      
      SaveFile();
   }

   void menuFileSaveAs_Click(object sender, System.EventArgs e){      
      SaveFileAs();
   }      

   void menuFileExit_Click(object sender, System.EventArgs e){      
      Close();
   }
   
   protected override void OnClosing(CancelEventArgs e){      
      Boolean cancel;
      CheckToSave(out cancel);
      if(cancel){
         e.Cancel = true;
      }else{
         base.OnClosing(e);
      }
   }

   void menuEditCut_Click(object sender, System.EventArgs e){
      text.Cut();
   }

   void menuEditCopy_Click(object sender, System.EventArgs e){
      text.Copy();
   }   

   void menuEditPaste_Click(object sender, System.EventArgs e){            
      text.Paste();
   }

   void menuEditUndo_Click(object sender, System.EventArgs e){
      text.Undo();
   }

   void menuEditDelete_Click(object sender, System.EventArgs e){
      text.SelectedText = String.Empty;
   }

   void menuEditSelectAll_Click(object sender, System.EventArgs e){
      text.SelectAll();
   } 

   void menuFormat_Popup(object sender, System.EventArgs e){
      this.menuFormatWordWrap.Checked = text.WordWrap;
   }

   void menuFormatWordWrap_Click(object sender, System.EventArgs e){
      text.WordWrap = !text.WordWrap;
   }   

   void menuFormatFont_Click(object sender, System.EventArgs e){
      SelectFont();
   }

   void text_TextChanged(object sender, System.EventArgs e){
      isDirty = true;
   }

   // Set everything back to square-one
   void ResetForm(){
      FileName = null;
      text.Text = String.Empty;
      isDirty = false;      
   }

   // Property for getting and setting FileName, sets up other odds and ends
   String FileName{
      get{return fileName;}
      set{
         if(value == null){
            menuFileSave.Enabled = false;
            Text = "Pad";
         }else{
            menuFileSave.Enabled = true;
            Text = Path.GetFileName(value)+" - Pad";
         }
         fileName = value;
      }
   }   

   // Check to see if we should ask the user if they would like to save
   void CheckToSave(out Boolean cancelOperation){
      cancelOperation = false;
      if(isDirty){
         DialogResult answer = MessageBox.Show(
            "The text in the document has changed.\n\n"+
            "Do you want to save changes?", "Pad", 
            MessageBoxButtons.YesNoCancel);
         switch(answer){
         case DialogResult.Yes:
            if(FileName == null){
               SaveFileAs();
            }else{
               SaveFile();
            }
            break;
         case DialogResult.No:
            break;
         default:
            cancelOperation = true;
            break;
         }
      }
   }

   // Open a file selected by the user
   void OpenFile(){
      Stream stream;
      OpenFileDialog ofd = new OpenFileDialog();

      
      ofd.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*" ;
      ofd.FilterIndex = 1 ;
      // Security Change
      // The following try catch block was added.  No real handling is
      // done since both of these lines implement non-critical features.
      try{
         ofd.InitialDirectory = "." ;
         ofd.RestoreDirectory = false ;
      }catch(SecurityException){}

      if(ofd.ShowDialog() == DialogResult.OK){
         if((stream = ofd.OpenFile())!= null){
            Boolean cancel;
            CheckToSave(out cancel);
            if(!cancel){               
               StreamReader reader = new StreamReader(stream, true);
               text.Text = reader.ReadToEnd();
               isDirty = false;
               reader.Close();
               // Security Change
               // try catch block added.  The restricted version never 
               // knows a filename
               try{FileName = ofd.FileName;}catch(SecurityException){}                          
            }
         }
      }
   }

   // Let the user select a filename to save the file as
   void SaveFileAs(){
      SaveFileDialog sfd = new SaveFileDialog();
 
      sfd.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"  ;
      sfd.FilterIndex = 1 ;
      // Security Change
      // The following try catch block was added.  No real handling is
      // done since this line implements a non-critical feature.
      try{sfd.RestoreDirectory = true ;}catch(SecurityException){}
 
      if(sfd.ShowDialog() == DialogResult.OK){
         // Security Change
         // This try catch block was added, the handler makes a call
         // to a new function added to support the secured functionality.
         // The original flow is shown in the try block.
         try{
            FileName = sfd.FileName;
            SaveFile();         
         }catch(SecurityException){
            SaveFile(sfd.OpenFile());
         }         
      }
   }
   
   // Security Change
   // The original SaveFile function was broken up into two.  One that
   // opens a stream from a filename, and another that saves the stream
   // and performs some maintenance.  This keeps the bulk of the logic
   // in one place, and nicely blends with the full-trust version which
   // needs to be able to save a file based on its name.
   void SaveFile(Stream stream){      
      StreamWriter writer = new StreamWriter(stream);
      writer.Write(text.Text);
      writer.Close();
      isDirty = false;      
   }

   // Security Change
   // Save the current file (if fails, SaveAs)
   void SaveFile(){
      try{
         SaveFile(new FileStream(FileName, FileMode.Create));         
      }catch(IOException){
         SaveFileAs();
      }
   }

   // Let the user select the font that they work with
   void SelectFont(){
      FontDialog fd = new FontDialog();
      fd.Font = text.Font;
      fd.Color = text.ForeColor;
      fd.ShowColor = true;
      if(fd.ShowDialog() != DialogResult.Cancel ){
         text.Font = fd.Font ;
         text.ForeColor = fd.Color;
      }
   } 
   
	#region Windows Form Designer generated code
   /// <summary>
   /// Required method for Designer support - do not modify
   /// the contents of this method with the code editor.
   /// </summary>
   private void InitializeComponent() {
      this.menuFormatFont = new System.Windows.Forms.MenuItem();
      this.mainMenu = new System.Windows.Forms.MainMenu();
      this.menuFile = new System.Windows.Forms.MenuItem();
      this.menuFileNew = new System.Windows.Forms.MenuItem();
      this.menuFileOpen = new System.Windows.Forms.MenuItem();
      this.menuFileSave = new System.Windows.Forms.MenuItem();
      this.menuFileSaveAs = new System.Windows.Forms.MenuItem();
      this.menuBar1 = new System.Windows.Forms.MenuItem();
      this.menuFileExit = new System.Windows.Forms.MenuItem();
      this.menuEdit = new System.Windows.Forms.MenuItem();
      this.menuEditUndo = new System.Windows.Forms.MenuItem();
      this.menuBar2 = new System.Windows.Forms.MenuItem();
      this.menuEditCut = new System.Windows.Forms.MenuItem();
      this.menuEditCopy = new System.Windows.Forms.MenuItem();
      this.menuEditPaste = new System.Windows.Forms.MenuItem();
      this.menuEditDelete = new System.Windows.Forms.MenuItem();
      this.menuBar3 = new System.Windows.Forms.MenuItem();
      this.menuEditSelectAll = new System.Windows.Forms.MenuItem();
      this.menuFormat = new System.Windows.Forms.MenuItem();
      this.menuFormatWordWrap = new System.Windows.Forms.MenuItem();
      this.text = new System.Windows.Forms.TextBox();
      this.status = new System.Windows.Forms.StatusBar();
      this.SuspendLayout();
      // 
      // menuFormatFont
      // 
      this.menuFormatFont.Index = 1;
      this.menuFormatFont.Text = "&Font...";
      this.menuFormatFont.Click += new System.EventHandler(this.menuFormatFont_Click);
      // 
      // mainMenu
      // 
      this.mainMenu.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
                                                                              this.menuFile,
                                                                              this.menuEdit,
                                                                              this.menuFormat});
      // 
      // menuFile
      // 
      this.menuFile.Index = 0;
      this.menuFile.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
                                                                              this.menuFileNew,
                                                                              this.menuFileOpen,
                                                                              this.menuFileSave,
                                                                              this.menuFileSaveAs,
                                                                              this.menuBar1,
                                                                              this.menuFileExit});
      this.menuFile.Text = "&File";
      // 
      // menuFileNew
      // 
      this.menuFileNew.Index = 0;
      this.menuFileNew.Text = "&New";
      this.menuFileNew.Click += new System.EventHandler(this.menuFileNew_Click);
      // 
      // menuFileOpen
      // 
      this.menuFileOpen.Index = 1;
      this.menuFileOpen.Text = "&Open...";
      this.menuFileOpen.Click += new System.EventHandler(this.menuFileOpen_Click);
      // 
      // menuFileSave
      // 
      this.menuFileSave.Index = 2;
      this.menuFileSave.Text = "&Save";
      this.menuFileSave.Click += new System.EventHandler(this.menuFileSave_Click);
      // 
      // menuFileSaveAs
      // 
      this.menuFileSaveAs.Index = 3;
      this.menuFileSaveAs.Text = "Save &As...";
      this.menuFileSaveAs.Click += new System.EventHandler(this.menuFileSaveAs_Click);
      // 
      // menuBar1
      // 
      this.menuBar1.Index = 4;
      this.menuBar1.Text = "-";
      // 
      // menuFileExit
      // 
      this.menuFileExit.Index = 5;
      this.menuFileExit.Text = "E&xit";
      this.menuFileExit.Click += new System.EventHandler(this.menuFileExit_Click);
      // 
      // menuEdit
      // 
      this.menuEdit.Index = 1;
      this.menuEdit.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
                                                                              this.menuEditUndo,
                                                                              this.menuBar2,
                                                                              this.menuEditCut,
                                                                              this.menuEditCopy,
                                                                              this.menuEditPaste,
                                                                              this.menuEditDelete,
                                                                              this.menuBar3,
                                                                              this.menuEditSelectAll});
      this.menuEdit.Text = "&Edit";
      // 
      // menuEditUndo
      // 
      this.menuEditUndo.Index = 0;
      this.menuEditUndo.Shortcut = System.Windows.Forms.Shortcut.CtrlZ;
      this.menuEditUndo.Text = "&Undo";
      this.menuEditUndo.Click += new System.EventHandler(this.menuEditUndo_Click);
      // 
      // menuBar2
      // 
      this.menuBar2.Index = 1;
      this.menuBar2.Text = "-";
      // 
      // menuEditCut
      // 
      this.menuEditCut.Index = 2;
      this.menuEditCut.Shortcut = System.Windows.Forms.Shortcut.CtrlX;
      this.menuEditCut.Text = "Cu&t";
      this.menuEditCut.Click += new System.EventHandler(this.menuEditCut_Click);
      // 
      // menuEditCopy
      // 
      this.menuEditCopy.Index = 3;
      this.menuEditCopy.Shortcut = System.Windows.Forms.Shortcut.CtrlC;
      this.menuEditCopy.Text = "&Copy";
      this.menuEditCopy.Click += new System.EventHandler(this.menuEditCopy_Click);
      // 
      // menuEditPaste
      // 
      this.menuEditPaste.Index = 4;
      this.menuEditPaste.Shortcut = System.Windows.Forms.Shortcut.CtrlV;
      this.menuEditPaste.Text = "&Paste";
      this.menuEditPaste.Click += new System.EventHandler(this.menuEditPaste_Click);
      // 
      // menuEditDelete
      // 
      this.menuEditDelete.Index = 5;
      this.menuEditDelete.Shortcut = System.Windows.Forms.Shortcut.Del;
      this.menuEditDelete.Text = "De&lete";
      this.menuEditDelete.Click += new System.EventHandler(this.menuEditDelete_Click);
      // 
      // menuBar3
      // 
      this.menuBar3.Index = 6;
      this.menuBar3.Text = "-";
      // 
      // menuEditSelectAll
      // 
      this.menuEditSelectAll.Index = 7;
      this.menuEditSelectAll.Shortcut = System.Windows.Forms.Shortcut.CtrlA;
      this.menuEditSelectAll.Text = "Select &All";
      this.menuEditSelectAll.Click += new System.EventHandler(this.menuEditSelectAll_Click);
      // 
      // menuFormat
      // 
      this.menuFormat.Index = 2;
      this.menuFormat.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
                                                                                this.menuFormatWordWrap,
                                                                                this.menuFormatFont});
      this.menuFormat.Text = "F&ormat";
      // 
      // menuFormatWordWrap
      // 
      this.menuFormatWordWrap.Index = 0;
      this.menuFormatWordWrap.Text = "&Word Wrap";
      this.menuFormatWordWrap.Click += new System.EventHandler(this.menuFormatWordWrap_Click);
      // 
      // text
      // 
      this.text.Anchor = (((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom) 
         | System.Windows.Forms.AnchorStyles.Left) 
         | System.Windows.Forms.AnchorStyles.Right);
      this.text.Font = new System.Drawing.Font("Lucida Console", 9.75F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((System.Byte)(0)));
      this.text.MaxLength = 0;
      this.text.Multiline = true;
      this.text.Name = "text";
      this.text.ScrollBars = System.Windows.Forms.ScrollBars.Both;
      this.text.Size = new System.Drawing.Size(592, 552);
      this.text.TabIndex = 0;
      this.text.Text = "";
      this.text.WordWrap = false;
      this.text.TextChanged += new System.EventHandler(this.text_TextChanged);
      // 
      // status
      // 
      this.status.Location = new System.Drawing.Point(0, 556);
      this.status.Name = "status";
      this.status.Size = new System.Drawing.Size(592, 20);
      this.status.TabIndex = 1;
      // 
      // CSPad
      // 
      this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
      this.ClientSize = new System.Drawing.Size(592, 576);
      this.Controls.AddRange(new System.Windows.Forms.Control[] {
                                                                   this.status,
                                                                   this.text});
      this.Menu = this.mainMenu;
      this.MinimumSize = new System.Drawing.Size(10, 10);
      this.Name = "CSPad";
      this.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen;
      this.Text = "CSPad";
      this.ResumeLayout(false);

   }
	#endregion        
}