package at.gv.egiz.pdfas.algorithmSuite;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * Defines a used algorithm suite. Contains a {@link #signatureMethod} a
 * {@link #dataDigestMethod} a {@link #propertiesDigestMethod} and a
 * {@link #certDigestMethod}.<br>
 * 
 * This structured object is representing a string like
 * <code>ecdsa-sha256:sha256:sha256:ripemd160</code><br>
 * meaning
 * <code>signatureMethod:dataDigestMethod:propertiesDigestMethod:certDigestMethod</code>
 * 
 * @author dferbas
 * 
 */
public class AlgorithmSuiteObject {
   private static Log log = LogFactory.getLog(AlgorithmSuiteObject.class);

   private String signatureMethod;
   private String dataDigestMethod;
   private String propertiesDigestMethod;
   private String certDigestMethod;

   /**
    * Create emtpy algorithm suite object
    */
   public AlgorithmSuiteObject() {

   }

   /**
    * Create object from parameter string like
    * <code>etsi-moc-1.2:ecdsa-sha1:ripemd160@207c44ff</code>
    * Prefix included
    * 
    * @param parameterString
    */
   public AlgorithmSuiteObject(String parameterString) {
      parseFrom(parameterString, true);
   }
   
   /**
    * Create object from parameter string like <br>
    * <code>etsi-moc-1.2:ecdsa-sha1:ripemd160@207c44ff</code> hasPrefix=true <br>
    * <code>ecdsa-sha1:ripemd160@207c44ff</code> hasPrefix=false
    * 
    * 
    * @param parameterString
    * @param hasPrefix parse with/without prefix (e.g. etsi-moc-1.2)
    */
   public AlgorithmSuiteObject(String parameterString, boolean hasPrefix) {
      parseFrom(parameterString, hasPrefix);
   }

   /**
    * Initializes object from parameter string like
    * <code>etsi-moc-1.2:ecdsa-sha1:ripemd160@207c44ff</code> hasPrefix=true <br>
    * <code>ecdsa-sha1:ripemd160@207c44ff</code> hasPrefix=false
    * 
    * @param parameterString
    * @param hasPrefix parse with/without prefix (e.g. etsi-moc-1.2)
    */
   public void parseFrom(String parameterString, boolean hasPrefix) {
      log.debug("parsing algorithmSuite from " + parameterString);
      if (parameterString != null) {
         parameterString = parameterString.split("@")[0];
         if (!hasPrefix) {
            parameterString = "bla:" + parameterString; // fake prefix
         }
         String[] arr = parameterString.split(":");         
         if (arr.length > 1) {
            this.signatureMethod = arr[1];
            this.dataDigestMethod = this.propertiesDigestMethod = this.certDigestMethod = AlgorithmMapper
                  .getHashAbbrFromSuite(arr[1]);

            if (arr.length > 2) {
               this.dataDigestMethod = this.propertiesDigestMethod = this.certDigestMethod = arr[2];
            }
            if (arr.length > 3) {
               this.propertiesDigestMethod = this.certDigestMethod = arr[3];
            }
            if (arr.length > 4) {
               this.certDigestMethod = arr[4];
            }
            log.debug("successfully parsed to: " + this.toString());
         }
      }
   }

   /**
    * Returns if algorithm object is valid specified (values are available)
    * 
    * @return
    */
   public boolean isSpecified() {
      return this.signatureMethod != null;
   }

   /**
    * Signature method abbreviation. E.g. rsa-sha1, ecdsa-sha256
    * 
    * @return
    */
   public String getSignatureMethod() {
      return this.signatureMethod;
   }

   /**
    * Digest method for data (document). E.g. sha1, md5
    * 
    * @return
    */
   public String getDataDigestMethod() {
      return this.dataDigestMethod;
   }

   /**
    * Digest method for properties. E.g. sha1, md5
    * 
    * @return
    */
   public String getPropertiesDigestMethod() {
      return this.propertiesDigestMethod;
   }

   /**
    * Digest method for certificate digest. E.g. sha1, md5
    * 
    * @return
    */
   public String getCertDigestMethod() {
      return this.certDigestMethod;
   }

   public void setSignatureMethod(String signatureMethod) {
      this.signatureMethod = signatureMethod;
   }

   public void setDataDigestMethod(String dataDigestMethod) {
      this.dataDigestMethod = dataDigestMethod;
   }

   public void setPropertiesDigestMethod(String propertiesDigestMethod) {
      this.propertiesDigestMethod = propertiesDigestMethod;
   }

   public void setCertDigestMethod(String certDigestMethod) {
      this.certDigestMethod = certDigestMethod;
   }

   public String toString() {
      return "AlgorithmSuiteObject [certDigestMethod=" + this.certDigestMethod
            + ", dataDigestMethod=" + this.dataDigestMethod + ", propertiesDigestMethod="
            + this.propertiesDigestMethod + ", signatureMethod=" + this.signatureMethod + "]";
   }

}