package org.spongycastle.asn1.crmf;

import org.spongycastle.asn1.ASN1Encodable;
import org.spongycastle.asn1.ASN1EncodableVector;
import org.spongycastle.asn1.ASN1Integer;
import org.spongycastle.asn1.DERBitString;
import org.spongycastle.asn1.DERSequence;
import org.spongycastle.asn1.DERTaggedObject;
import org.spongycastle.asn1.x500.X500Name;
import org.spongycastle.asn1.x509.AlgorithmIdentifier;
import org.spongycastle.asn1.x509.Extensions;
import org.spongycastle.asn1.x509.SubjectPublicKeyInfo;
import org.spongycastle.asn1.x509.X509Extensions;

public class CertTemplateBuilder
{
    private ASN1Integer version;
    private ASN1Integer serialNumber;
    private AlgorithmIdentifier signingAlg;
    private X500Name issuer;
    private OptionalValidity validity;
    private X500Name subject;
    private SubjectPublicKeyInfo publicKey;
    private DERBitString issuerUID;
    private DERBitString subjectUID;
    private Extensions extensions;

    /** Sets the X.509 version. Note: for X509v3, use 2 here. */
    public CertTemplateBuilder setVersion(int ver)
    {
        version = new ASN1Integer(ver);

        return this;
    }

    public CertTemplateBuilder setSerialNumber(ASN1Integer ser)
    {
        serialNumber = ser;

        return this;
    }

    public CertTemplateBuilder setSigningAlg(AlgorithmIdentifier aid)
    {
        signingAlg = aid;

        return this;
    }

    public CertTemplateBuilder setIssuer(X500Name name)
    {
        issuer = name;

        return this;
    }

    public CertTemplateBuilder setValidity(OptionalValidity v)
    {
        validity = v;

        return this;
    }

    public CertTemplateBuilder setSubject(X500Name name)
    {
        subject = name;

        return this;
    }

    public CertTemplateBuilder setPublicKey(SubjectPublicKeyInfo spki)
    {
        publicKey = spki;

        return this;
    }

    /** Sets the issuer unique ID (deprecated in X.509v3) */
    public CertTemplateBuilder setIssuerUID(DERBitString uid)
    {
        issuerUID = uid;

        return this;
    }

    /** Sets the subject unique ID (deprecated in X.509v3) */
    public CertTemplateBuilder setSubjectUID(DERBitString uid)
    {
        subjectUID = uid;

        return this;
    }

    /**
     * @deprecated use method taking Extensions
     * @param extens
     * @return
     */
    public CertTemplateBuilder setExtensions(X509Extensions extens)
    {
        return setExtensions(Extensions.getInstance(extens));
    }

    public CertTemplateBuilder setExtensions(Extensions extens)
    {
        extensions = extens;

        return this;
    }

    /**
     * <pre>
     *  CertTemplate ::= SEQUENCE {
     *      version      [0] Version               OPTIONAL,
     *      serialNumber [1] INTEGER               OPTIONAL,
     *      signingAlg   [2] AlgorithmIdentifier   OPTIONAL,
     *      issuer       [3] Name                  OPTIONAL,
     *      validity     [4] OptionalValidity      OPTIONAL,
     *      subject      [5] Name                  OPTIONAL,
     *      publicKey    [6] SubjectPublicKeyInfo  OPTIONAL,
     *      issuerUID    [7] UniqueIdentifier      OPTIONAL,
     *      subjectUID   [8] UniqueIdentifier      OPTIONAL,
     *      extensions   [9] Extensions            OPTIONAL }
     * </pre>
     * @return a basic ASN.1 object representation.
     */
    public CertTemplate build()
    {
        ASN1EncodableVector v = new ASN1EncodableVector();

        addOptional(v, 0, false, version);
        addOptional(v, 1, false, serialNumber);
        addOptional(v, 2, false, signingAlg);
        addOptional(v, 3, true, issuer); // CHOICE
        addOptional(v, 4, false, validity);
        addOptional(v, 5, true, subject); // CHOICE
        addOptional(v, 6, false, publicKey);
        addOptional(v, 7, false, issuerUID);
        addOptional(v, 8, false, subjectUID);
        addOptional(v, 9, false, extensions);

        return CertTemplate.getInstance(new DERSequence(v));
    }

    private void addOptional(ASN1EncodableVector v, int tagNo, boolean isExplicit, ASN1Encodable obj)
    {
        if (obj != null)
        {
            v.add(new DERTaggedObject(isExplicit, tagNo, obj));
        }
    }
}
