import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Task;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.Namespace;
import org.dom4j.QName;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;

/**
 * Update dendences in project xml on all modules in nbm form locatated is the specified folder
 * @author pzajac
 */
public class UpdateFeatureDeps extends Task {

    private static final String NBM_EXT = ".nbm";
    private static final String PRJ_NAME_SPACE = "http://www.netbeans.org/ns/project/1";
    private static final String DATA_NAME_SPACE = "http://www.netbeans.org/ns/nb-module-project/3";

    private File nbmFolder;
    private File projectXmlFile;
    private String cnd;
    /**  entries for unit testing in order to avoid scanning modules
     */

    /** Creates a new instance of FixTestClassPath */
    public UpdateFeatureDeps() {
    }

    public void setProjectXml(File projectXml) {
        projectXmlFile = projectXml;

    }
    public void setNbmFolder(File file) {
        nbmFolder = file;
    }
    
    
    public void execute() throws BuildException {
        // read project xml

        try {
            // test mode doesn't override project.xml
            if (projectXmlFile == null || !projectXmlFile.isFile()) {
                throw new BuildException("project.xml file doesn't exist.");
            }

            if (nbmFolder == null || !nbmFolder.isDirectory()) {
                throw new BuildException("nbmfolder doesn't exist or is not folder: " + nbmFolder);
            }

            // start parse project xml 
            SAXReader reader = new SAXReader();
            Document doc = reader.read(projectXmlFile);
            Element rootElement = doc.getRootElement();
            Element data = getDel(getPel(rootElement, "configuration"), "data");
            Element dataEl = getDel(data,"module-dependencies"); 
            cnd = getDel(data,"code-name-base").getText();
            if (dataEl == null) {
                throw new BuildException("No module dependencies tag in " + projectXmlFile);
            }
            // remove all current dependecies
            dataEl.clearContent();

            // add new dependencies
            for (File file : nbmFolder.listFiles()) {
                if (file.isFile() && file.getName().endsWith(NBM_EXT)) {
                    // create dependency from nbm file
                    ZipFile zf = new ZipFile(file);
                    try {
                        String name = file.getName();
                        String cnb = name.replace(NBM_EXT,"");
                        System.out.println("cnb:" + cnb);
                        ZipEntry entry = zf.getEntry("netbeans/config/Modules/" + cnb + ".xml");

                        InputStream is = zf.getInputStream(entry);
                        try {
                            Document moduleDoc = reader.read(is);
                            List elements = moduleDoc.selectNodes("//module/param");
                            String specVersion = null;
                            String release = null;
                            for (Object elObj : elements) {
                                Element el = (Element) elObj;
                                String nameVal = el.attributeValue("name");
                                if ("specversion".equals(nameVal)) {
                                    specVersion = el.getTextTrim();
                                }
                                if ("release".equals(nameVal)) {
                                    release = el.getTextTrim();
                                }
                            }

                            addDepEntry(cnb, specVersion, release, dataEl);
                        } finally {
                            is.close();
                        }
                    } finally {
                        zf.close();
                    }

                }
            }
        // store project.properties and project.xml
            FileWriter fileWriter = new FileWriter( projectXmlFile );
            try {
                XMLWriter writer = new XMLWriter(fileWriter,OutputFormat.createPrettyPrint() );
                writer.write( doc );
                writer.close();
            } finally {
                fileWriter.close();
            }
        } catch (IOException ioe) {
            throw new BuildException(ioe);
        } catch (DocumentException de) {
            throw new BuildException(de);
        }

    }


    private void addDepEntry(String name, String specVersion, String releaseVersion, Element dataEl) {
        name = name.replace('-', '.');
        if (!cnd.equals(name)) {
            Element depEl = addDel(dataEl,"dependency");
            Element cndEl = addDel(depEl,"code-name-base");
            cndEl.setText(name);
            Element runEl = addDel(depEl,"run-dependency");
            if (releaseVersion != null) {
                Element relEl = addDel(runEl,"release-version");
                relEl.setText(releaseVersion);
            }
            Element specEl = addDel(runEl,"specification-version");
            specEl.setText( specVersion);
        }
    }
    
    private Element getPel(Element el,String name) {
        return el.element(QName.get(name, Namespace.get(PRJ_NAME_SPACE)));
    }
    
    private Element getDel(Element el,String name) {
        return el.element(QName.get(name, Namespace.get(DATA_NAME_SPACE)));
    }
    private Element addDel(Element dataEl, String name) {
        return dataEl.addElement(QName.get(name, Namespace.get(DATA_NAME_SPACE)));
    }
}