package org.sufficientlysecure.keychain.pgp;

import org.spongycastle.openpgp.PGPException;
import org.spongycastle.openpgp.PGPOnePassSignature;
import org.spongycastle.openpgp.PGPPublicKey;
import org.spongycastle.openpgp.PGPSignature;
import org.spongycastle.openpgp.operator.jcajce.JcaPGPContentVerifierBuilderProvider;
import org.spongycastle.openpgp.operator.jcajce.JcePublicKeyKeyEncryptionMethodGenerator;
import org.sufficientlysecure.keychain.Constants;
import org.sufficientlysecure.keychain.util.IterableIterator;

import java.security.SignatureException;

public class CachedPublicKey extends UncachedPublicKey {

    // this is the parent key ring
    final CachedKeyRing mRing;

    CachedPublicKey(CachedKeyRing ring, PGPPublicKey key) {
        super(key);
        mRing = ring;
    }

    public IterableIterator<String> getUserIds() {
        return new IterableIterator<String>(mPublicKey.getUserIDs());
    }

    public CachedKeyRing getKeyRing() {
        return mRing;
    }

    JcePublicKeyKeyEncryptionMethodGenerator getPubKeyEncryptionGenerator() {
        return  new JcePublicKeyKeyEncryptionMethodGenerator(mPublicKey);
    }

    public void initSignature(PGPSignature sig) throws PGPException {
        JcaPGPContentVerifierBuilderProvider contentVerifierBuilderProvider =
                new JcaPGPContentVerifierBuilderProvider()
                        .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME);
        sig.init(contentVerifierBuilderProvider, mPublicKey);
    }

    public void initSignature(PGPOnePassSignature sig) throws PGPException {
        JcaPGPContentVerifierBuilderProvider contentVerifierBuilderProvider =
                new JcaPGPContentVerifierBuilderProvider()
                        .setProvider(Constants.BOUNCY_CASTLE_PROVIDER_NAME);
        sig.init(contentVerifierBuilderProvider, mPublicKey);
    }

    /** Verify a signature for this pubkey, after it has been initialized by the signer using
     * initSignature(). This method should probably move into a wrapped PGPSignature class
     * at some point.
     */
    public boolean verifySignature(PGPSignature sig, String uid) throws PGPException {
        try {
            return sig.verifyCertification(uid, mPublicKey);
        } catch (SignatureException e) {
            throw new PGPException("Error!", e);
        }
    }

}