package org.kuali.common.devops.logic;
   
   import static com.google.common.base.Optional.absent;
   import static com.google.common.base.Optional.fromNullable;
   import static com.google.common.collect.Lists.newArrayList;
   
   import java.util.List;
   import java.util.Properties;
   
  import org.apache.commons.lang.StringUtils;
  import org.kuali.common.util.LocationUtils;
  import org.kuali.common.util.project.model.ImmutableProject;
  import org.kuali.common.util.project.model.Project;
  
  import com.google.common.base.Joiner;
  import com.google.common.base.Optional;
  import com.google.common.base.Splitter;
  
  public class Projects extends Examiner {
  
  	private static final String BUNDLE_SYMBOLIC_NAME_KEY = "Bundle-SymbolicName";
  
  	public static Project getProjectWithAccurateSCMInfo(Project project, Properties manifest) {
  		Optional<String> bundleSymbolicName = fromNullable(manifest.getProperty(BUNDLE_SYMBOLIC_NAME_KEY));
  		if (!bundleSymbolicName.isPresent()) {
  			return ImmutableProject.copyOf(project);
  		} else {
  			Properties newProps = new Properties();
  			newProps.putAll(project.getProperties());
  
  			// Most reliable way to get SVN information is from the manifest. This method attempts to get it from both
  			// MANIFEST.MF and project.properties. It also verifies that it can actually contact whatever location it locates
  			// before returning it
  			Optional<String> url = getScmUrl(manifest, newProps);
  			String revision = getScmRevision(manifest);
  
  			if (url.isPresent()) {
  				// Override whatever is in the project properties with what we found
  				newProps.setProperty(SCM_URL_KEY, url.get());
  				newProps.setProperty(SCM_REVISION_KEY, revision);
  			} else {
  				// Remove these 2 properties so nothing can even attempt to display inaccurate SCM info
  				newProps.remove(SCM_URL_KEY);
  				newProps.remove(SCM_REVISION_KEY);
  			}
  			return new ImmutableProject(project.getGroupId(), project.getArtifactId(), project.getVersion(), newProps);
  		}
  	}
  
  	/**
  	 * Returns Optional.absent() unless we can locate a live URL that we can actually contact
  	 */
  	private static Optional<String> getScmUrl(Properties manifest, Properties properties) {
  		// Most reliable method for getting the url is via MANIFEST.MF
  		Optional<String> url = getScmUrlFromManifest(manifest);
  		if (url.isPresent()) {
  			// If we found one, we are done
  			return url;
  		} else {
  			// If MANIFEST.MF fails, try to get it from project.properties
  			// The problem here, is that Maven assumes artifactId == directory name for sub-modules
  			// If that isn't the case, the URL from project.properties points to a non-existent location
  			return getScmUrlFromProperties(properties);
  		}
  	}
  
  	private static Optional<String> getScmUrlFromManifest(Properties manifest) {
  		String url = manifest.getProperty("SVN-URL");
  		if (url == null) {
  			return absent();
  		}
  		if (url.indexOf("${") != -1) {
  			return absent();
  		}
  		if (!LocationUtils.exists(url)) {
  			return absent();
  		}
  		return Optional.of(url);
  	}
  
  	private static Optional<String> getScmUrlFromProperties(Properties properties) {
  		String url = properties.getProperty("project.scm.url");
  		if (url == null) {
  			return Optional.absent();
  		}
  		List<String> tokens = newArrayList(Splitter.on(':').splitToList(url));
  		tokens.remove(0); // scm
  		tokens.remove(0); // svn
  		String newUrl = Joiner.on(':').join(tokens);
  
  		// Make sure the location actually exists
  		if (LocationUtils.exists(newUrl)) {
  			return Optional.of(newUrl);
  		} else {
  			return absent();
  		}
  	}
  
  	private static String getScmRevision(Properties manifest) {
 		String revision = StringUtils.trimToNull(manifest.getProperty("SVN-Revision"));
 		if (revision == null || revision.indexOf("${") != -1) {
 			return "n/a";
 		} else {
 			return revision;
 		}
 	}
 
 }