package itext_test.sign;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.security.KeyStore;
import java.security.cert.Certificate;
import java.security.PrivateKey;
import com.lowagie.text.Rectangle;
import com.lowagie.text.pdf.PdfReader;
import com.lowagie.text.pdf.PdfStamper;
import com.lowagie.text.pdf.PdfSignatureAppearance;
import java.io.File;
import java.security.Security;

public class SignByDigitalID
{
    static final int SIGNTYPE_INVISIBLE = 0;
    static final int SIGNTYPE_VISIBLE = 1;
    static final int SIGNTYPE_FIELD = 2;

    public static void main(String[] args) throws Exception
    {
        if (!new File("HelloWorld.pdf").exists())
            com.lowagie.examples.general.HelloWorld.main(null);

        // If you don't use BouncyCastle as a security provider, you have to modify the next line.
        if (Security.getProvider("BC") == null)
            Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());

        stampSignature("HelloWorld.pdf", "VisibleSigned.pdf", "self-sign-test.pfx", "password", SIGNTYPE_VISIBLE, null, false, new Rectangle(100, 100, 200, 200), 1, "Signed by visible signature.", "Hyogo");
        stampSignature("HelloWorld.pdf", "InvisibleSigned.pdf", "self-sign-test.pfx", "password", SIGNTYPE_INVISIBLE, null, false, null, 0, "Signed by invisible signature.", "Takarazuka");
        stampSignature("SignatureField.pdf", "SignedOnField.pdf", "self-sign-test.pfx", "password", SIGNTYPE_FIELD, "Signature", false, null, 0, "Signed on a field.", "Japan");
        stampSignature("SignedOnField.pdf", "MultiSigned.pdf", "self-sign-test2.pfx", "password2", SIGNTYPE_VISIBLE, null, true, new Rectangle(300, 100, 400, 200), 1, "Multi-Signed by visible signature.", "Tokyo");
    }

    static void stampSignature(String filename, String signedFilename,
        String keyFilename, String password,
        int signType, String fieldName, boolean append,
        Rectangle rect, int page,
        String reason, String location) throws Exception
    {
        KeyStore ks = KeyStore.getInstance("PKCS12");
        ks.load(new FileInputStream(keyFilename), password.toCharArray());
        String alias = (String)ks.aliases().nextElement();
        PrivateKey key = (PrivateKey)ks.getKey(alias, password.toCharArray());
        Certificate[] chain = ks.getCertificateChain(alias);

        PdfReader reader = new PdfReader(filename);
        FileOutputStream fout = new FileOutputStream(signedFilename);
        PdfStamper stp = PdfStamper.createSignature(reader, fout, '\0', (File)null, append);

        PdfSignatureAppearance sap = stp.getSignatureAppearance();
        sap.setCrypto(key, chain, null, PdfSignatureAppearance.SELF_SIGNED);
        sap.setReason(reason);
        sap.setLocation(location);

        switch (signType)
        {
            case SIGNTYPE_VISIBLE:
                sap.setVisibleSignature(rect, page, fieldName);
                break;
            case SIGNTYPE_FIELD:
                sap.setVisibleSignature(fieldName);
                break;
            default:
                break;
        }

        stp.close();
    }
}