/*

  * To change this template, choose Tools | Templates

  * and open the template in the editor.

  */

 package org.apidesign.livedb.impl;

 import java.io.IOException;

 import java.io.Writer;

 import java.sql.CallableStatement;

 import java.sql.Connection;

 import java.sql.Driver;

 import java.sql.DriverManager;

 import java.sql.ResultSet;

 import java.sql.ResultSetMetaData;

 import java.sql.SQLException;

 import java.util.Enumeration;

 import java.util.Properties;

 import java.util.ServiceLoader;

 import java.util.Set;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import javax.annotation.processing.AbstractProcessor;

 import javax.annotation.processing.Processor;

 import javax.annotation.processing.RoundEnvironment;

 import javax.annotation.processing.SupportedAnnotationTypes;

 import javax.annotation.processing.SupportedSourceVersion;

 import javax.lang.model.SourceVersion;

 import javax.lang.model.element.Element;

 import javax.lang.model.element.PackageElement;

 import javax.lang.model.element.TypeElement;

 import javax.tools.JavaFileObject;

 import org.apidesign.livedb.LiveDB;

 import org.openide.util.lookup.ServiceProvider;

 /**

  *

  * @author Jaroslav Tulach <jtulach@netbeans.org>

  */

 @SupportedAnnotationTypes("org.apidesign.livedb.LiveDB")

 @SupportedSourceVersion(SourceVersion.RELEASE_6)

 @ServiceProvider(service=Processor.class)

 public class LiveDBProcessor extends AbstractProcessor {

     @Override

     public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {

         for (Element e : roundEnv.getElementsAnnotatedWith(LiveDB.class)) {

             LiveDB db = e.getAnnotation(LiveDB.class);

             PackageElement pe = (PackageElement)e;

             String clsName = pe.getQualifiedName().toString() + "." + db.classname();

             try {

                 JavaFileObject src = processingEnv.getFiler().createSourceFile(clsName, pe);

                 Writer w = src.openWriter();

                 Connection c = getConnection(db.url(), db.user(), db.password());

                 CallableStatement s = c.prepareCall(db.query());

                 ResultSet rs = s.executeQuery();

                 ResultSetMetaData md = rs.getMetaData();

                 w.append("package " + pe.getQualifiedName() + ";\n");

                 w.append("import java.util.List;\n");

                 w.append("import java.util.ArrayList;\n");

                 w.append("import java.sql.*;\n");

                 w.append("class " + db.classname() + " {\n");

                 for (int i = 1; i <= md.getColumnCount(); i++) {

                     w.append("  public final " + md.getColumnClassName(i) + " " + md.getColumnName(i) + ";\n");

                 }

                 w.append("  private " + db.classname() + "(\n");

                 for (int i = 1; i <= md.getColumnCount(); i++) {

                     w.append("    " + md.getColumnClassName(i) + " " + md.getColumnName(i));

                     if (i < md.getColumnCount()) {

                         w.append(",\n");

                     } else {

                         w.append("\n");

                     }

                 }

                 w.append("  ) {\n");

                 for (int i = 1; i <= md.getColumnCount(); i++) {

                     w.append("    this." + md.getColumnName(i) + " = " + md.getColumnName(i) + ";\n");

                 }

                 w.append("  }\n");

                 w.append("  public static List<" + db.classname() + "> query() throws SQLException {\n");

                 w.append("    Connection c = DriverManager.getConnection(\"" + db.url() + "\", \"" + db.user() + "\", \"" + db.password() +"\");\n");

                 w.append("    List<" + db.classname() + "> res = new ArrayList<" + db.classname() + ">();\n");

                 w.append("    CallableStatement s = c.prepareCall(\"" + db.query() + "\");\n");

                 w.append("    ResultSet rs = s.executeQuery();\n");

                 w.append("    ResultSetMetaData md = rs.getMetaData();\n");

                 w.append("    while (rs.next()) {\n");

                 w.append("      res.add(new " + db.classname() + "(\n");

                 for (int i = 1; i <= md.getColumnCount(); i++) {

                     w.append("        (" + md.getColumnClassName(i) + ")rs.getObject(" + i + ")");

                     if (i < md.getColumnCount()) {

                         w.append(",\n");

                     } else {

                         w.append("\n");

                     }

                 }

                 w.append("      ));\n");

                 w.append("    };\n");

                 w.append("    return res;\n");

                 w.append("  }");

                 w.append("}");

                 w.close();

             } catch (IOException ex) {

                 throw new IllegalStateException(ex);

             } catch (SQLException ex) {

                 throw new IllegalStateException(ex);

             }

         }

         return true;

     }

     private static Connection getConnection(String url, String user, String password) 

     throws SQLException {

         final ClassLoader cl = LiveDBProcessor.class.getClassLoader();

         for (Driver d : ServiceLoader.load(Driver.class, cl)) {

 //            System.out.println("looked up: " + d);

             if (d.acceptsURL(url)) {

                 //System.out.println("accepts: " + d);

                 Properties p = new Properties();

                 p.put("user", user);

                 p.put("password", password);

                 return d.connect(url, p);

             }

         }

         throw new SQLException("No driver found for " + url);

     }

 }