/*! ******************************************************************************
 *
 * Pentaho Data Integration
 *
 * Copyright (C) 2002-2019 by Hitachi Vantara : http://www.pentaho.com
 *
 *******************************************************************************
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 ******************************************************************************/

package org.pentaho.di.ui.trans.steps.blockuntilstepsfinish;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.ShellAdapter;
import org.eclipse.swt.events.ShellEvent;
import org.eclipse.swt.layout.FormAttachment;
import org.eclipse.swt.layout.FormData;
import org.eclipse.swt.layout.FormLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableItem;
import org.eclipse.swt.widgets.Text;
import org.pentaho.di.core.Const;
import org.pentaho.di.core.annotations.PluginDialog;
import org.pentaho.di.core.util.Utils;
import org.pentaho.di.i18n.BaseMessages;
import org.pentaho.di.trans.TransMeta;
import org.pentaho.di.trans.step.BaseStepMeta;
import org.pentaho.di.trans.step.StepDialogInterface;
import org.pentaho.di.trans.step.StepMeta;
import org.pentaho.di.trans.steps.blockuntilstepsfinish.BlockUntilStepsFinishMeta;
import org.pentaho.di.ui.core.widget.ColumnInfo;
import org.pentaho.di.ui.core.widget.TableView;
import org.pentaho.di.ui.trans.step.BaseStepDialog;


@PluginDialog( id = "BlockUntilStepsFinish", image = "WFS.svg", pluginType = PluginDialog.PluginType.STEP,
  documentationUrl = "http://wiki.pentaho.com/display/EAI/Block+this+step+until+steps+finish" )
public class BlockUntilStepsFinishDialog extends BaseStepDialog implements StepDialogInterface {
  private static Class<?> PKG = BlockUntilStepsFinishDialog.class; // for i18n purposes, needed by Translator2!!

  private String[] previousSteps;
  private BlockUntilStepsFinishMeta input;

  private Label wlFields;
  private TableView wFields;
  private FormData fdlFields, fdFields;

  public BlockUntilStepsFinishDialog( Shell parent, Object in, TransMeta tr, String sname ) {
    super( parent, (BaseStepMeta) in, tr, sname );
    input = (BlockUntilStepsFinishMeta) in;
  }

  public String open() {
    Shell parent = getParent();
    Display display = parent.getDisplay();

    shell = new Shell( parent, SWT.DIALOG_TRIM | SWT.RESIZE | SWT.MIN | SWT.MAX );
    props.setLook( shell );
    setShellImage( shell, input );

    ModifyListener lsMod = new ModifyListener() {
      public void modifyText( ModifyEvent e ) {
        input.setChanged();
      }
    };
    changed = input.hasChanged();

    FormLayout formLayout = new FormLayout();
    formLayout.marginWidth = Const.FORM_MARGIN;
    formLayout.marginHeight = Const.FORM_MARGIN;

    shell.setLayout( formLayout );
    shell.setText( BaseMessages.getString( PKG, "BlockUntilStepsFinishDialog.Shell.Title" ) );

    int middle = props.getMiddlePct();
    int margin = Const.MARGIN;

    // Stepname line
    wlStepname = new Label( shell, SWT.RIGHT );
    wlStepname.setText( BaseMessages.getString( PKG, "BlockUntilStepsFinishDialog.Stepname.Label" ) );
    props.setLook( wlStepname );
    fdlStepname = new FormData();
    fdlStepname.left = new FormAttachment( 0, 0 );
    fdlStepname.right = new FormAttachment( middle, -margin );
    fdlStepname.top = new FormAttachment( 0, margin );
    wlStepname.setLayoutData( fdlStepname );
    wStepname = new Text( shell, SWT.SINGLE | SWT.LEFT | SWT.BORDER );
    wStepname.setText( stepname );
    props.setLook( wStepname );
    wStepname.addModifyListener( lsMod );
    fdStepname = new FormData();
    fdStepname.left = new FormAttachment( middle, 0 );
    fdStepname.top = new FormAttachment( 0, margin );
    fdStepname.right = new FormAttachment( 100, 0 );
    wStepname.setLayoutData( fdStepname );

    // Get the previous steps...
    setStepNames();

    wOK = new Button( shell, SWT.PUSH );
    wOK.setText( BaseMessages.getString( PKG, "System.Button.OK" ) );
    wGet = new Button( shell, SWT.PUSH );
    wGet.setText( BaseMessages.getString( PKG, "BlockUntilStepsFinishDialog.getSteps.Label" ) );
    wCancel = new Button( shell, SWT.PUSH );
    wCancel.setText( BaseMessages.getString( PKG, "System.Button.Cancel" ) );

    setButtonPositions( new Button[] { wOK, wGet, wCancel }, margin, null );

    // Table with fields
    wlFields = new Label( shell, SWT.NONE );
    wlFields.setText( BaseMessages.getString( PKG, "BlockUntilStepsFinishDialog.Fields.Label" ) );
    props.setLook( wlFields );
    fdlFields = new FormData();
    fdlFields.left = new FormAttachment( 0, 0 );
    fdlFields.top = new FormAttachment( wStepname, margin );
    wlFields.setLayoutData( fdlFields );

    final int FieldsCols = 2;
    final int FieldsRows = input.getStepName().length;

    ColumnInfo[] colinf = new ColumnInfo[FieldsCols];
    colinf[0] =
      new ColumnInfo(
        BaseMessages.getString( PKG, "BlockUntilStepsFinishDialog.Fieldname.Step" ),
        ColumnInfo.COLUMN_TYPE_CCOMBO, previousSteps, false );
    colinf[1] =
      new ColumnInfo(
        BaseMessages.getString( PKG, "BlockUntilStepsFinishDialog.Fieldname.CopyNr" ),
        ColumnInfo.COLUMN_TYPE_TEXT, false );
    colinf[1].setUsingVariables( true );
    wFields =
      new TableView(
        transMeta, shell, SWT.BORDER | SWT.FULL_SELECTION | SWT.MULTI, colinf, FieldsRows, lsMod, props );

    fdFields = new FormData();
    fdFields.left = new FormAttachment( 0, 0 );
    fdFields.top = new FormAttachment( wlFields, margin );
    fdFields.right = new FormAttachment( 100, 0 );
    fdFields.bottom = new FormAttachment( wOK, -2 * margin );
    wFields.setLayoutData( fdFields );

    // Add listeners
    lsCancel = new Listener() {
      public void handleEvent( Event e ) {
        cancel();
      }
    };
    lsGet = new Listener() {
      public void handleEvent( Event e ) {
        get();
      }
    };
    lsOK = new Listener() {
      public void handleEvent( Event e ) {
        ok();
      }
    };

    wCancel.addListener( SWT.Selection, lsCancel );
    wOK.addListener( SWT.Selection, lsOK );
    wGet.addListener( SWT.Selection, lsGet );

    lsDef = new SelectionAdapter() {
      public void widgetDefaultSelected( SelectionEvent e ) {
        ok();
      }
    };

    wStepname.addSelectionListener( lsDef );

    // Detect X or ALT-F4 or something that kills this window...
    shell.addShellListener( new ShellAdapter() {
      public void shellClosed( ShellEvent e ) {
        cancel();
      }
    } );

    // Set the shell size, based upon previous time...
    setSize();

    getData();
    input.setChanged( changed );

    shell.open();
    while ( !shell.isDisposed() ) {
      if ( !display.readAndDispatch() ) {
        display.sleep();
      }
    }
    return stepname;
  }

  private void setStepNames() {
    previousSteps = transMeta.getStepNames();
    String[] nextSteps = transMeta.getNextStepNames( stepMeta );

    List<String> entries = new ArrayList<String>();
    for ( int i = 0; i < previousSteps.length; i++ ) {
      if ( !previousSteps[i].equals( stepname ) ) {
        if ( nextSteps != null ) {
          for ( int j = 0; j < nextSteps.length; j++ ) {
            if ( !nextSteps[j].equals( previousSteps[i] ) ) {
              entries.add( previousSteps[i] );
            }
          }
        }
      }
    }
    previousSteps = entries.toArray( new String[entries.size()] );
  }

  private void get() {
    wFields.removeAll();
    Table table = wFields.table;

    for ( int i = 0; i < previousSteps.length; i++ ) {
      TableItem ti = new TableItem( table, SWT.NONE );
      ti.setText( 0, "" + ( i + 1 ) );
      ti.setText( 1, previousSteps[i] );
      ti.setText( 2, "0" );
    }
    wFields.removeEmptyRows();
    wFields.setRowNums();
    wFields.optWidth( true );

  }

  /**
   * Copy information from the meta-data input to the dialog fields.
   */
  public void getData() {
    Table table = wFields.table;
    if ( input.getStepName().length > 0 ) {
      table.removeAll();
    }
    for ( int i = 0; i < input.getStepName().length; i++ ) {
      TableItem ti = new TableItem( table, SWT.NONE );
      ti.setText( 0, "" + ( i + 1 ) );
      if ( input.getStepName()[i] != null ) {
        ti.setText( 1, input.getStepName()[i] );
        ti.setText( 2, "" + Const.toInt( input.getStepCopyNr()[i], 0 ) );
      }
    }

    wFields.removeEmptyRows();
    wFields.setRowNums();
    wFields.optWidth( true );

    wStepname.selectAll();
    wStepname.setFocus();
  }

  private void cancel() {
    stepname = null;
    input.setChanged( changed );
    dispose();
  }

  private void ok() {
    if ( Utils.isEmpty( wStepname.getText() ) ) {
      return;
    }
    stepname = wStepname.getText(); // return value

    int nrsteps = wFields.nrNonEmpty();
    input.allocate( nrsteps );
    for ( int i = 0; i < nrsteps; i++ ) {
      TableItem ti = wFields.getNonEmpty( i );
      StepMeta tm = transMeta.findStep( ti.getText( 1 ) );
      if ( tm != null ) {
        //CHECKSTYLE:Indentation:OFF
        input.getStepName()[i] = tm.getName();
        input.getStepCopyNr()[i] = String.valueOf( Const.toInt( ti.getText( 2 ), 0 ) );
      }

    }
    dispose();
  }
}
