package com.aragost.javahg;

 import com.aragost.javahg.internals.AbstractCommand;

 /**

  * Exception thrown when an attempt it made to execute a command that

  * the underlying Mercurial command server doesn't know.

  * <p>

  * Since Mercurial from time to time introduce new commands (e.g.

  * phase, graft), JavaHg implements these. But if you attempt to use

  * them against an older version of Mercurial you get this exception.

  * 

  */

 public class UnknownCommandException extends RuntimeException {

     private static final long serialVersionUID = 1L;

     // TODO Exceptions are Serializable, AbstractCommand not. So we

     // should not have it as a non-transient field.

     private final AbstractCommand command;

     public UnknownCommandException(AbstractCommand cmd) {

         super(createMessage(cmd));

         this.command = cmd;

     }

     private static String createMessage(AbstractCommand cmd) {

         HgVersion hgVersion = getHgVersion(cmd);

         return "Mercurial command '" + cmd.getCommandName() + "' is not supported by Mercurial version: "

                 + hgVersion.getVersionString();

     }

     private static HgVersion getHgVersion(AbstractCommand cmd) {

         HgVersion hgVersion = HgVersion.unknown();

         try {

             hgVersion = cmd.getRepository().getHgVersion();

         } catch (RuntimeException e) {

             // Something went wrong, but ignore this so we can create

             // this exception

         }

         return hgVersion;

     }

     public AbstractCommand getCommand() {

         return command;

     }

 }