package cn.home1.oss.lib.common.crypto;
   
   import io.jsonwebtoken.Jwts;
   
   import lombok.Getter;
   
   import org.joda.time.DateTime;
   
   import java.util.Date;
  
  import cn.home1.oss.lib.common.Defaults;
  
  /**
   * Created by zhanghaolun on 16/11/17.
   */
  public class JwtEncryptor implements EncodeEncryptor {
  
    @Getter
    private final JwtKey key;
  
    public JwtEncryptor(final KeyExpression keyExpression) {
      this.key = new JwtKey(keyExpression);
    }
  
    @Override
    public String encrypt(final String plainText) {
      throw new UnsupportedOperationException("jwt without maxAge is not supported.");
    }
  
    @Override
    public String encrypt(final String plainText, final Integer maxAge) {
      return this.buildCompactJws(plainText, Defaults.now(), maxAge);
    }
  
    public String buildCompactJws(final String token, final DateTime now, final Integer maxAge) {
      final Date expiration = now.plusSeconds(maxAge).toDate();
      return token != null ? Jwts.builder()
        .setSubject(token)
        .signWith(this.key.getSignatureAlgorithm(), this.key.getSignatureKey())
        .setExpiration(expiration)
        .compact() : null;
    }
  }