/*
 * SecureBlackbox 2024 .NET Edition - Sample Project
 *
 * This sample project demonstrates the usage of SecureBlackbox in a 
 * simple, straightforward way. It is not intended to be a complete 
 * application. Error handling and other checks are simplified for clarity.
 *
 * www.nsoftware.com/secureblackbox
 *
 * This code is subject to the terms and conditions specified in the 
 * corresponding product license agreement which outlines the authorized 
 * usage and restrictions.
 * 
 */

using System;
using System.Windows.Forms;
using nsoftware.SecureBlackbox;
using System.Text;
using System.Linq;

namespace PDFSignerDemo
{
    /// <summary>
    /// Summary description for frmMain.
    /// </summary>
    public class MainForm : System.Windows.Forms.Form
    {
        private System.Windows.Forms.Label lbInputFile;
        private System.Windows.Forms.TextBox edInputFile;
        private System.Windows.Forms.Button sbBrowseInputFile;
        private System.Windows.Forms.OpenFileDialog dlgOpen;
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.Container components = null;
        private System.Windows.Forms.Button btnSign;
        private TextBox edOutputFile;
        private Button button1;
        private Label label2;
        
        private SaveFileDialog dlgSave;
        public CheckBox cbVisible;
        private Label label1;
        private ComboBox cbLevel;
        private Button btnBrowseCert;
        private TextBox edCertPassword;
        private TextBox edSigningCertificate;
        private Label lCertPassword;
        private Label label6;
        private Label label7;
        private GroupBox groupBox5;
        private Label label3;
        private Button btnBrowseKey;
        private TextBox edSigningKey;
        private Label label4;
        private PDFSigner signer;

        public MainForm()
        {
            //
            // Required for Windows Form Designer support
            //
            InitializeComponent();

            //
            // TODO: Add any constructor code after InitializeComponent call
            //
            signer = new PDFSigner();
            signer.OnExternalSign += new PDFSigner.OnExternalSignHandler(DoExternalSign);

            cbLevel.SelectedIndex = 1;
        }

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        protected override void Dispose(bool disposing)
        {
            if (disposing)
            {
                if (components != null)
                {
                    components.Dispose();
                    signer.Dispose();
                }
            }
            base.Dispose(disposing);
        }

        public static byte[] HexStringToByteArray(string hex)
        {
            return Enumerable.Range(0, hex.Length)
                             .Where(x => x % 2 == 0)
                             .Select(x => Convert.ToByte(hex.Substring(x, 2), 16))
                             .ToArray();
        }

        public static string ByteArrayToHexString(byte[] ba)
        {
            StringBuilder hex = new StringBuilder(ba.Length * 2);
            foreach (byte b in ba)
                hex.AppendFormat("{0:x2}", b);
            return hex.ToString();
        }

        private void DoExternalSign(object sender, PDFSignerExternalSignEventArgs e)
        {
            PublicKeyCrypto crypto = new PublicKeyCrypto();

            try
            {
                CryptoKeyManager keymanager = new CryptoKeyManager();

                keymanager.ImportFromFile(edSigningKey.Text, 3, "", "", e.Pars, 0, "");

                crypto.Key = keymanager.Key;
            }
            catch (Exception ex)
            {
                MessageBox.Show("Cannot load key!");
            }

            try
            {
                crypto.HashAlgorithm = e.HashAlgorithm;
                crypto.InputIsHash = true;
                crypto.SchemeParams = e.Pars;

                var inBuf = HexStringToByteArray(e.Data);
                var outBuf = crypto.Sign(inBuf, true);

                e.SignedData = ByteArrayToHexString(outBuf);
                }
            catch (Exception ex)
            {
                MessageBox.Show("Cannot sign data!");
            }
        }

        #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.lbInputFile = new System.Windows.Forms.Label();
            this.edInputFile = new System.Windows.Forms.TextBox();
            this.sbBrowseInputFile = new System.Windows.Forms.Button();
            this.btnSign = new System.Windows.Forms.Button();
            this.dlgOpen = new System.Windows.Forms.OpenFileDialog();
            this.edOutputFile = new System.Windows.Forms.TextBox();
            this.button1 = new System.Windows.Forms.Button();
            this.label2 = new System.Windows.Forms.Label();
            this.dlgSave = new System.Windows.Forms.SaveFileDialog();
            this.cbVisible = new System.Windows.Forms.CheckBox();
            this.label1 = new System.Windows.Forms.Label();
            this.cbLevel = new System.Windows.Forms.ComboBox();
            this.btnBrowseCert = new System.Windows.Forms.Button();
            this.edCertPassword = new System.Windows.Forms.TextBox();
            this.edSigningCertificate = new System.Windows.Forms.TextBox();
            this.lCertPassword = new System.Windows.Forms.Label();
            this.label6 = new System.Windows.Forms.Label();
            this.label7 = new System.Windows.Forms.Label();
            this.groupBox5 = new System.Windows.Forms.GroupBox();
            this.label3 = new System.Windows.Forms.Label();
            this.btnBrowseKey = new System.Windows.Forms.Button();
            this.edSigningKey = new System.Windows.Forms.TextBox();
            this.label4 = new System.Windows.Forms.Label();
            this.groupBox5.SuspendLayout();
            this.SuspendLayout();
            // 
            // lbInputFile
            // 
            this.lbInputFile.Location = new System.Drawing.Point(5, 52);
            this.lbInputFile.Name = "lbInputFile";
            this.lbInputFile.Size = new System.Drawing.Size(60, 13);
            this.lbInputFile.TabIndex = 0;
            this.lbInputFile.Text = "Input file:";
            // 
            // edInputFile
            // 
            this.edInputFile.Location = new System.Drawing.Point(70, 49);
            this.edInputFile.Name = "edInputFile";
            this.edInputFile.Size = new System.Drawing.Size(334, 20);
            this.edInputFile.TabIndex = 1;
            // 
            // sbBrowseInputFile
            // 
            this.sbBrowseInputFile.Location = new System.Drawing.Point(410, 46);
            this.sbBrowseInputFile.Name = "sbBrowseInputFile";
            this.sbBrowseInputFile.Size = new System.Drawing.Size(75, 25);
            this.sbBrowseInputFile.TabIndex = 2;
            this.sbBrowseInputFile.Text = "Browse...";
            this.sbBrowseInputFile.Click += new System.EventHandler(this.sbBrowseInputFile_Click);
            // 
            // btnSign
            // 
            this.btnSign.Location = new System.Drawing.Point(410, 321);
            this.btnSign.Name = "btnSign";
            this.btnSign.Size = new System.Drawing.Size(75, 25);
            this.btnSign.TabIndex = 8;
            this.btnSign.Text = "Sign";
            this.btnSign.Click += new System.EventHandler(this.btnSign_Click);
            // 
            // edOutputFile
            // 
            this.edOutputFile.Location = new System.Drawing.Point(70, 79);
            this.edOutputFile.Name = "edOutputFile";
            this.edOutputFile.Size = new System.Drawing.Size(334, 20);
            this.edOutputFile.TabIndex = 19;
            // 
            // button1
            // 
            this.button1.Location = new System.Drawing.Point(410, 76);
            this.button1.Name = "button1";
            this.button1.Size = new System.Drawing.Size(75, 25);
            this.button1.TabIndex = 20;
            this.button1.Text = "Browse...";
            this.button1.Click += new System.EventHandler(this.button1_Click);
            // 
            // label2
            // 
            this.label2.Location = new System.Drawing.Point(5, 82);
            this.label2.Name = "label2";
            this.label2.Size = new System.Drawing.Size(60, 13);
            this.label2.TabIndex = 18;
            this.label2.Text = "Output file:";
            // 
            // cbVisible
            // 
            this.cbVisible.AutoSize = true;
            this.cbVisible.Checked = true;
            this.cbVisible.CheckState = System.Windows.Forms.CheckState.Checked;
            this.cbVisible.Location = new System.Drawing.Point(203, 32);
            this.cbVisible.Name = "cbVisible";
            this.cbVisible.Size = new System.Drawing.Size(102, 17);
            this.cbVisible.TabIndex = 25;
            this.cbVisible.Text = "Visible signature";
            // 
            // label1
            // 
            this.label1.AutoSize = true;
            this.label1.Location = new System.Drawing.Point(7, 33);
            this.label1.Name = "label1";
            this.label1.Size = new System.Drawing.Size(33, 13);
            this.label1.TabIndex = 34;
            this.label1.Text = "Level";
            // 
            // cbLevel
            // 
            this.cbLevel.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
            this.cbLevel.FormattingEnabled = true;
            this.cbLevel.Items.AddRange(new object[] {
            "Legacy",
            "Baseline B",
            "Baseline T",
            "Baseline LT",
            "Baseline LTA",
            "BES",
            "EPES",
            "LTV"});
            this.cbLevel.Location = new System.Drawing.Point(54, 30);
            this.cbLevel.Name = "cbLevel";
            this.cbLevel.Size = new System.Drawing.Size(121, 21);
            this.cbLevel.TabIndex = 35;
            // 
            // btnBrowseCert
            // 
            this.btnBrowseCert.Location = new System.Drawing.Point(270, 73);
            this.btnBrowseCert.Name = "btnBrowseCert";
            this.btnBrowseCert.Size = new System.Drawing.Size(75, 25);
            this.btnBrowseCert.TabIndex = 43;
            this.btnBrowseCert.Text = "Browse...";
            this.btnBrowseCert.Click += new System.EventHandler(this.btnBrowseCert_Click);
            // 
            // edCertPassword
            // 
            this.edCertPassword.Location = new System.Drawing.Point(115, 110);
            this.edCertPassword.Name = "edCertPassword";
            this.edCertPassword.PasswordChar = '*';
            this.edCertPassword.Size = new System.Drawing.Size(230, 20);
            this.edCertPassword.TabIndex = 42;
            // 
            // edSigningCertificate
            // 
            this.edSigningCertificate.Location = new System.Drawing.Point(10, 76);
            this.edSigningCertificate.Name = "edSigningCertificate";
            this.edSigningCertificate.Size = new System.Drawing.Size(254, 20);
            this.edSigningCertificate.TabIndex = 41;
            // 
            // lCertPassword
            // 
            this.lCertPassword.AutoSize = true;
            this.lCertPassword.Location = new System.Drawing.Point(7, 113);
            this.lCertPassword.Name = "lCertPassword";
            this.lCertPassword.Size = new System.Drawing.Size(105, 13);
            this.lCertPassword.TabIndex = 40;
            this.lCertPassword.Text = "Certificate password:";
            // 
            // label6
            // 
            this.label6.AutoSize = true;
            this.label6.Location = new System.Drawing.Point(7, 60);
            this.label6.Name = "label6";
            this.label6.Size = new System.Drawing.Size(94, 13);
            this.label6.TabIndex = 44;
            this.label6.Text = "Signing certificate:";
            // 
            // label7
            // 
            this.label7.AutoSize = true;
            this.label7.ForeColor = System.Drawing.SystemColors.Highlight;
            this.label7.Location = new System.Drawing.Point(5, 5);
            this.label7.Name = "label7";
            this.label7.Size = new System.Drawing.Size(402, 13);
            this.label7.TabIndex = 45;
            this.label7.Text = "This sample illustrates the use of PDFSigner component for signing PDF documents." +
    "";
            // 
            // groupBox5
            // 
            this.groupBox5.Controls.Add(this.label3);
            this.groupBox5.Controls.Add(this.btnBrowseKey);
            this.groupBox5.Controls.Add(this.edSigningKey);
            this.groupBox5.Controls.Add(this.cbLevel);
            this.groupBox5.Controls.Add(this.cbVisible);
            this.groupBox5.Controls.Add(this.label6);
            this.groupBox5.Controls.Add(this.btnBrowseCert);
            this.groupBox5.Controls.Add(this.label1);
            this.groupBox5.Controls.Add(this.edCertPassword);
            this.groupBox5.Controls.Add(this.lCertPassword);
            this.groupBox5.Controls.Add(this.edSigningCertificate);
            this.groupBox5.Location = new System.Drawing.Point(5, 114);
            this.groupBox5.Name = "groupBox5";
            this.groupBox5.Size = new System.Drawing.Size(480, 197);
            this.groupBox5.TabIndex = 46;
            this.groupBox5.TabStop = false;
            this.groupBox5.Text = "Signing options  ";
            // 
            // label3
            // 
            this.label3.AutoSize = true;
            this.label3.Location = new System.Drawing.Point(7, 150);
            this.label3.Name = "label3";
            this.label3.Size = new System.Drawing.Size(135, 13);
            this.label3.TabIndex = 47;
            this.label3.Text = "Key file for external signing:";
            // 
            // btnBrowseKey
            // 
            this.btnBrowseKey.Location = new System.Drawing.Point(270, 163);
            this.btnBrowseKey.Name = "btnBrowseKey";
            this.btnBrowseKey.Size = new System.Drawing.Size(75, 25);
            this.btnBrowseKey.TabIndex = 46;
            this.btnBrowseKey.Text = "Browse...";
            this.btnBrowseKey.Click += new System.EventHandler(this.btnBrowseKey_Click);
            // 
            // edSigningKey
            // 
            this.edSigningKey.Location = new System.Drawing.Point(10, 166);
            this.edSigningKey.Name = "edSigningKey";
            this.edSigningKey.Size = new System.Drawing.Size(254, 20);
            this.edSigningKey.TabIndex = 45;
            // 
            // label4
            // 
            this.label4.AutoSize = true;
            this.label4.ForeColor = System.Drawing.SystemColors.Highlight;
            this.label4.Location = new System.Drawing.Point(5, 24);
            this.label4.Name = "label4";
            this.label4.Size = new System.Drawing.Size(245, 13);
            this.label4.TabIndex = 47;
            this.label4.Text = "Please pick the signing certificate and click \'Sign\'. ";
            // 
            // MainForm
            // 
            this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
            this.ClientSize = new System.Drawing.Size(494, 355);
            this.Controls.Add(this.label4);
            this.Controls.Add(this.groupBox5);
            this.Controls.Add(this.label7);
            this.Controls.Add(this.edOutputFile);
            this.Controls.Add(this.button1);
            this.Controls.Add(this.label2);
            this.Controls.Add(this.edInputFile);
            this.Controls.Add(this.btnSign);
            this.Controls.Add(this.sbBrowseInputFile);
            this.Controls.Add(this.lbInputFile);
            this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle;
            this.MaximizeBox = false;
            this.Name = "MainForm";
            this.StartPosition = System.Windows.Forms.FormStartPosition.CenterScreen;
            this.Text = "PDF Signer Demo";
            this.groupBox5.ResumeLayout(false);
            this.groupBox5.PerformLayout();
            this.ResumeLayout(false);
            this.PerformLayout();

        }
        #endregion

        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.Run(new MainForm());
        }

        private void sbBrowseInputFile_Click(object sender, System.EventArgs e)
        {
            dlgOpen.InitialDirectory = Application.StartupPath;
            dlgOpen.FileName = edInputFile.Text;
            if (dlgOpen.ShowDialog() == DialogResult.OK)
                edInputFile.Text = dlgOpen.FileName;
        }

        public Certificate LoadCertificate(string file, string password)
        {
            Certificate cert = null;

            if (file.Length > 0)
            {
                try
                {
                    CertificateManager certmanager = new CertificateManager();

                    certmanager.ImportFromFile(file, password);

                    cert = certmanager.Certificate;
                }
                catch (Exception e)
                {
                    MessageBox.Show("Cannot load certificate!");
                }
            }

            return cert;
        }

        private void btnSign_Click(object sender, System.EventArgs e)
        {
            signer.InputFile = edInputFile.Text;
            signer.OutputFile = edOutputFile.Text;

            signer.SigningCertificate = LoadCertificate(edSigningCertificate.Text, edCertPassword.Text);

            if (signer.SigningCertificate.KeyAlgorithm.Contains("id-dsa"))
            {
                MessageBox.Show("The certificate was found to contain a DSA key. The hash algorithm has been switched to SHA1.");

                signer.NewSignature.HashAlgorithm = "SHA1";
            }

            signer.NewSignature.SignatureType = PDFSignatureTypes.pstPAdES;

            switch (cbLevel.SelectedIndex)
            {
                case 0: signer.NewSignature.Level = PAdESSignatureLevels.paslGeneric; break;
                case 1: signer.NewSignature.Level = PAdESSignatureLevels.paslBaselineB; break;
                case 2: signer.NewSignature.Level = PAdESSignatureLevels.paslBaselineT; break;
                case 3: signer.NewSignature.Level = PAdESSignatureLevels.paslBaselineLT; break;
                case 4: signer.NewSignature.Level = PAdESSignatureLevels.paslBaselineLTA; break;
                case 5: signer.NewSignature.Level = PAdESSignatureLevels.paslBES; break;
                case 6: signer.NewSignature.Level = PAdESSignatureLevels.paslEPES; break;
                case 7: signer.NewSignature.Level = PAdESSignatureLevels.paslLTV; break;
            }
            signer.Widget.Invisible = !cbVisible.Checked;

            signer.IgnoreChainValidationErrors = true;

            signer.NewSignature.AuthorName = "test demo author";
            signer.NewSignature.Reason = "test demo reason";

            signer.ExternalCrypto.Mode = ExternalCryptoModes.ecmGeneric;

            try
            {
                signer.SignExternal();

                MessageBox.Show("PDF file successfully signed");
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }

        private void button1_Click(object sender, EventArgs e)
        {
            dlgSave.InitialDirectory = Application.StartupPath;
            dlgSave.FileName = edInputFile.Text;
            if (dlgSave.ShowDialog() == DialogResult.OK)
                edOutputFile.Text = dlgSave.FileName;
        }

        private void btnBrowseCert_Click(object sender, EventArgs e)
        {
            if (dlgOpen.ShowDialog() == DialogResult.OK)
                edSigningCertificate.Text = dlgOpen.FileName;
        }

        private void btnBrowseKey_Click(object sender, EventArgs e)
        {
            if (dlgOpen.ShowDialog() == DialogResult.OK)
                edSigningKey.Text = dlgOpen.FileName;
        }
    }
}