/*
 * QuerySpanGridModel.java
 *
 * Copyright 2000 Eliad Technologies, Inc. All Rights Reserved.
 *
 * This software is the proprietary information of Eliad Technologies, Inc.
 */
 
package example08;

import java.util.*;
import java.sql.*;
import com.eliad.model.*;

/**
 * This class implements a procedural span model.
 * @author Daniel Rosenblatt
 * @version 1.0
 */
public class QuerySpanGridModel extends GenericGridModel {

  private Connection connection_;
  private Statement statement_;
  private String query_;
  private AbstractGridModel columnHeaderModel_;
  private AbstractSpanModel spanModel_=new SpannedViewSpanModel();
  private boolean spanned_;
  private TreeSet spannedRows_ = new TreeSet();
  
  public QuerySpanGridModel(String url,String driverName)
  throws ClassNotFoundException, SQLException {
    this(url,driverName,"","");
  }
  public QuerySpanGridModel(String url,String driverName,String user,String passwd)
  throws ClassNotFoundException, SQLException {
    Class.forName(driverName);
    connection_ = DriverManager.getConnection(url, user, passwd);
    statement_ = connection_.createStatement();
  }

  public void setQuery(String query) {
    if (connection_ == null || statement_ == null)
      throw new IllegalStateException("There is no database or statement to execute the query.");
    try {
      query_ = query;
      ResultSet resultSet = statement_.executeQuery(query);
      ResultSetMetaData metaData = resultSet.getMetaData();
      final int colCount = metaData.getColumnCount();

      final String[] colNames = new String[colCount];
      for (int i = 0; i < colCount; i++)
        colNames[i] = metaData.getColumnName(i+1);

      columnHeaderModel_ = new AbstractGridModel () {
        public int getRowCount() {
          return 1;
        }
        public int getColumnCount() {
          if (spanned_)
            return colCount -  1;
          return colCount;
        }
        public Object getValueAt(int row, int column) {
          if (spanned_)
            column++;
          return colNames[column];
        }
      };
      
      // Get all rows.
      Vector rows = new Vector();
      while (resultSet.next()) {
        Vector newRow = new Vector(colCount);
        for (int i = 0; i < colCount; i++)
          newRow.add(resultSet.getObject(i+1));
        rows.add(newRow);
      }
      setDataVector(rows);
      resultSet.close();
    } catch (SQLException ex) {
        System.err.println(ex);
    }
  }

  public int getColumnCount() {
    if (spanned_)
      return  super.getColumnCount() - 1;
    return  super.getColumnCount();
  }
  
  public Object getValueAt(int row, int column) {
    if (spanned_)
      column++;
    return super.getValueAt(row, column);
  }
  
  public boolean isSpanned() {
    return spanned_;
  }
  
  public void setSpanned(boolean spanned) {
    if (spanned_ != spanned) {
      String label=(String)columnHeaderModel_.getValueAt(0,0);
      spanned_ = spanned;
      if (spanned) {
        Object spanValue = null;
        for (int row = 0; row < getRowCount(); row++) {
          Object curValue = super.getValueAt(row, 0);
          if (spanValue!=null && !spanValue.equals(curValue) ||
              spanValue==null && curValue!=null) {
            spanValue = curValue;
            Vector newRow = new Vector();
            for (int j=0;j<super.getColumnCount();j++)
              newRow.add(label + ": " + curValue);
            insertRow (row, newRow);
            spannedRows_.add(new Integer(row++));
          }
        }
      } else {
        int deltaRow = 0;
        for (Iterator i = spannedRows_.iterator(); i.hasNext(); ) {
          Integer row = (Integer)i.next();
          removeRows(row.intValue()-deltaRow++, 1);
        }
        spannedRows_.clear();
      }
      fireGridModelChanged();
      columnHeaderModel_.fireGridModelChanged();
      spanModel_.fireSpanModelChanged();
    }
  }

  public boolean isCellEditable(int row, int column) {
    return false;
  }
  
  private class SpannedViewSpanModel extends AbstractQuerySpanModel {
    public ExtentCell getSpanOver(final int row, int column) {
      if (!spanned_ || !spannedRows_.contains(new Integer(row)))
        return null;
      return new ExtentCell() {
        public int getRow() {
          return row;
        }
        public int getRowCount() {
          return 1;
        }
        public int getColumn() {
          return 0;
        }
        public int getColumnCount() {
          return QuerySpanGridModel.this.getColumnCount();
        }
        public Object getIdentifier() {
          return null;
        }
      };
    }
    
    public boolean isEmpty() {
      return !spanned_ || spannedRows_.isEmpty();
    }
  }

  public String getQuery() {
    return query_;
  }
  
  public GridModel getColumnHeaderModel() {
    return columnHeaderModel_;
  }

  public SpanModel getSpanModel() {
    return spanModel_;
  }

  public void close() throws SQLException {
    statement_.close();
    connection_.close();
  }

  protected void finalize() throws Throwable {
    try {
      close();
    } finally {
      super.finalize();
    }
  }
}