package org.kuali.core.db.torque;

 import java.io.File;

 import java.util.ArrayList;

 import java.util.List;

 import java.util.Set;

 import java.util.TreeSet;

 import org.apache.tools.ant.BuildException;

 import org.apache.tools.ant.DirectoryScanner;

 import org.apache.tools.ant.Project;

 import org.apache.tools.ant.types.FileSet;

 import org.apache.torque.engine.database.model.Database;

 import org.apache.torque.engine.database.model.Table;

 import org.apache.torque.engine.database.transform.XmlToData;

 import org.apache.torque.task.TorqueDataModelTask;

 import org.apache.velocity.VelocityContext;

 import org.apache.velocity.context.Context;

 import org.springframework.util.StringUtils;

 /**

  * This task converts data XML files into SQL files. It uses schema.xml to analyze which tables have a corresponding

  * data XML file

  */

 public class KualiTorqueDataSQLTask extends TorqueDataModelTask {

         PrettyPrint prettyPrint;

         Utils utils = new Utils();

         /**

          * The DTD itself.

          */

         protected File dataDTD;

         /**

          * Database object representing the information from schema.xml

          */

         protected Database database;

         /**

          * Get a list of File objects from the directory and filenames passed in

          */

         protected List<File> getFiles(File srcDir, String[] filenames) {

                 List<File> files = new ArrayList<File>();

                 for (int i = 0; i < filenames.length; i++) {

                         files.add(new File(srcDir, filenames[i]));

                 }

                 return files;

         }

         /**

          * Cycle through the filesets to generate a list of file objects

          */

         protected List<File> getFiles(List<FileSet> fileSets, Project project) {

                 List<File> files = new ArrayList<File>();

                 for (FileSet fileSet : fileSets) {

                         DirectoryScanner ds = fileSet.getDirectoryScanner(project);

                         File srcDir = fileSet.getDir(project);

                         files.addAll(getFiles(srcDir, ds.getIncludedFiles()));

                 }

                 return files;

         }

         /**

          * Extract table names from schema.xml

          */

         protected Set<String> getTableNamesFromSchemaXML(Database database) {

                 List<?> tables = database.getTables();

                 Set<String> tablenames = new TreeSet<String>();

                 for (Object object : tables) {

                         Table table = (Table) object;

                         tablenames.add(table.getName());

                 }

                 return tablenames;

         }

         /**

          * Extract table names from files on the file system

          */

         protected Set<String> getTableNamesFromFiles(List<File> files) {

                 Set<String> tablenames = new TreeSet<String>();

                 for (File file : files) {

                         String filename = file.getName();

                         int pos = filename.indexOf(".xml");

                         String tablename = filename.substring(0, pos);

                         tablenames.add(tablename);

                 }

                 return tablenames;

         }

         /**

          * Initialize a Velocity context that can generate SQL from XML data files

          */

         public Context initControlContext() throws Exception {

                 if (getFilesets().isEmpty()) {

                         throw new BuildException("You must specify a fileset of XML data files!");

                 }

                 // Get an xml parser for schema.xml

                 KualiXmlToAppData xmlParser = new KualiXmlToAppData(getTargetDatabase(), "");

                 // Parse schema.xml into a database object

                 Database database = xmlParser.parseResource(getXmlFile());

                 setDatabase(database);

                 // Locate the DTD

                 if (!getDataDTD().exists()) {

                         throw new BuildException("Could not find the DTD for " + database.getName());

                 }

                 // These are the XML data files

                 List<File> files = getFiles(getFilesets(), getProject());

                 // Resolve table information from the data XML files with table information from schema.xml

                 Set<String> schemaTables = getTableNamesFromSchemaXML(database);

                 Set<String> fileTables = getTableNamesFromFiles(files);

                 Set<String> missingFiles = SetUtils.difference(schemaTables, fileTables);

                 Set<String> intersection = SetUtils.intersection(schemaTables, fileTables);

                 Set<String> extraFiles = SetUtils.difference(fileTables, schemaTables);

                 log("Total tables: " + database.getTables().size());

                 log("Tables with data XML files: " + intersection.size());

                 log("Tables without data XML files: " + missingFiles.size());

                 if (extraFiles.size() > 0) {

                         log("There are files that have no corresponding entry in schema.xml: " + extraFiles.size(), Project.MSG_WARN);

                 }

                 // Setup the Velocity context

                 VelocityContext context = new VelocityContext();

                 context.put("xmlfiles", files);

                 context.put("task", this);

                 context.put("targetDatabase", getTargetDatabase());

                 return context;

         }

         public void onBeforeGenerate(File file) {

                 prettyPrint = new PrettyPrint("[INFO] Generating: " + getTargetDatabase() + "/" + StringUtils.replace(file.getName(), ".xml", ".sql"));

                 utils.left(prettyPrint);

         }

         public void onAfterGenerate(File file) {

                 utils.right(prettyPrint);

                 prettyPrint = null;

         }

         /**

          * Parse a data XML file. This method gets invoked from the Velocity template - sql/load/Control.vm

          */

         public List<?> getData(File file) {

                 try {

                         XmlToData dataXmlParser = new XmlToData(getDatabase(), getDataDTD().getAbsolutePath());

                         List<?> newData = dataXmlParser.parseFile(file.getAbsolutePath());

                         return newData;

                 } catch (Exception e) {

                         throw new BuildException(e);

                 }

         }

         public Database getDatabase() {

                 return database;

         }

         public void setDatabase(Database database) {

                 this.database = database;

         }

         public File getDataDTD() {

                 return dataDTD;

         }

         public void setDataDTD(File dataDTD) {

                 this.dataDTD = dataDTD;

         }

 }