GuidedDecisionTableModellerContextMenuSupport.java

/*
 * Copyright 2016 Red Hat, Inc. and/or its affiliates.
 *
 * 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.drools.workbench.screens.guided.dtable.client.widget.table;

import javax.enterprise.context.Dependent;
import javax.inject.Inject;

import com.ait.lienzo.client.core.types.Point2D;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.EventTarget;
import com.google.gwt.dom.client.NativeEvent;
import com.google.gwt.event.dom.client.ContextMenuEvent;
import com.google.gwt.event.dom.client.ContextMenuHandler;
import com.google.gwt.event.dom.client.MouseDownEvent;
import com.google.gwt.event.dom.client.MouseDownHandler;
import org.drools.workbench.screens.guided.dtable.client.editor.menu.CellContextMenu;
import org.drools.workbench.screens.guided.dtable.client.editor.menu.RowContextMenu;
import org.uberfire.ext.wires.core.grids.client.model.GridCell;
import org.uberfire.ext.wires.core.grids.client.model.GridColumn;
import org.uberfire.ext.wires.core.grids.client.model.GridData;
import org.uberfire.ext.wires.core.grids.client.util.CoordinateUtilities;
import org.uberfire.ext.wires.core.grids.client.widget.dnd.IsRowDragHandle;
import org.uberfire.ext.wires.core.grids.client.widget.grid.selections.CellSelectionStrategy;
import org.uberfire.ext.wires.core.grids.client.widget.grid.selections.impl.RangeSelectionStrategy;

@Dependent
public class GuidedDecisionTableModellerContextMenuSupport {

    private final CellContextMenu cellContextMenu;
    private final RowContextMenu rowContextMenu;

    @Inject
    public GuidedDecisionTableModellerContextMenuSupport( final CellContextMenu cellContextMenu,
                                                          final RowContextMenu rowContextMenu ) {
        this.cellContextMenu = cellContextMenu;
        this.rowContextMenu = rowContextMenu;
    }

    public ContextMenuHandler getContextMenuHandler( final GuidedDecisionTableModellerView.Presenter modellerPresenter ) {
        return new GuidedDecisionTableModellerContextMenuHandler( modellerPresenter,
                                                                  cellContextMenu,
                                                                  rowContextMenu );
    }

    public MouseDownHandler getContextMenuMouseDownHandler() {
        return new GuidedDecisionTableModellerContextMenuMouseDownHandler( cellContextMenu,
                                                                           rowContextMenu );
    }

    private static class GuidedDecisionTableModellerContextMenuHandler implements ContextMenuHandler {

        private final GuidedDecisionTableModellerView.Presenter modellerPresenter;
        private final CellContextMenu cellContextMenu;
        private final RowContextMenu rowContextMenu;

        public GuidedDecisionTableModellerContextMenuHandler( final GuidedDecisionTableModellerView.Presenter modellerPresenter,
                                                              final CellContextMenu cellContextMenu,
                                                              final RowContextMenu rowContextMenu ) {
            this.modellerPresenter = modellerPresenter;
            this.cellContextMenu = cellContextMenu;
            this.rowContextMenu = rowContextMenu;
        }

        @Override
        public void onContextMenu( final ContextMenuEvent event ) {
            event.preventDefault();
            event.stopPropagation();
            final boolean isShiftKeyDown = event.getNativeEvent().getShiftKey();
            final boolean isControlKeyDown = event.getNativeEvent().getCtrlKey();
            final int eventX = event.getNativeEvent().getClientX();
            final int eventY = event.getNativeEvent().getClientY();
            final int canvasX = getRelativeX( event );
            final int canvasY = getRelativeY( event );

            for ( GuidedDecisionTableView.Presenter dtPresenter : modellerPresenter.getAvailableDecisionTables() ) {
                final GuidedDecisionTableView gridView = dtPresenter.getView();
                final GridData gridModel = gridView.getModel();

                final Point2D ap = CoordinateUtilities.convertDOMToGridCoordinate( gridView,
                                                                                   new Point2D( canvasX,
                                                                                                canvasY ) );
                final Integer uiRowIndex = CoordinateUtilities.getUiRowIndex( gridView,
                                                                              ap.getY() );
                final Integer uiColumnIndex = CoordinateUtilities.getUiColumnIndex( gridView,
                                                                                    ap.getX() );
                if ( uiRowIndex == null || uiColumnIndex == null ) {
                    continue;
                }

                final GridColumn<?> column = gridModel.getColumns().get( uiColumnIndex );
                if ( column instanceof IsRowDragHandle ) {
                    rowContextMenu.show( eventX,
                                         eventY );

                } else {
                    cellContextMenu.show( eventX,
                                          eventY );
                }
                selectCell( uiRowIndex,
                            uiColumnIndex,
                            gridView,
                            isShiftKeyDown,
                            isControlKeyDown );
            }
        }

        private int getRelativeX( final ContextMenuEvent event ) {
            final NativeEvent e = event.getNativeEvent();
            final Element target = event.getRelativeElement();
            return e.getClientX() - target.getAbsoluteLeft() + target.getScrollLeft() + target.getOwnerDocument().getScrollLeft();
        }

        private int getRelativeY( final ContextMenuEvent event ) {
            final NativeEvent e = event.getNativeEvent();
            final Element target = event.getRelativeElement();
            return e.getClientY() - target.getAbsoluteTop() + target.getScrollTop() + target.getOwnerDocument().getScrollTop();
        }

        private void selectCell( final int uiRowIndex,
                                 final int uiColumnIndex,
                                 final GuidedDecisionTableView gridView,
                                 final boolean isShiftKeyDown,
                                 final boolean isControlKeyDown ) {
            //Lookup CellSelectionManager for cell
            final GridData gridModel = gridView.getModel();

            CellSelectionStrategy selectionStrategy;
            final GridCell<?> cell = gridModel.getCell( uiRowIndex,
                                                        uiColumnIndex );
            if ( cell == null ) {
                selectionStrategy = RangeSelectionStrategy.INSTANCE;
            } else {
                selectionStrategy = cell.getSelectionManager();
            }
            if ( selectionStrategy == null ) {
                return;
            }

            //Handle selection
            if ( selectionStrategy.handleSelection( gridModel,
                                                    uiRowIndex,
                                                    uiColumnIndex,
                                                    isShiftKeyDown,
                                                    isControlKeyDown ) ) {
                gridView.getLayer().batch();
            }
        }

    }

    private static class GuidedDecisionTableModellerContextMenuMouseDownHandler implements MouseDownHandler {

        private final CellContextMenu cellContextMenu;
        private final RowContextMenu rowContextMenu;

        public GuidedDecisionTableModellerContextMenuMouseDownHandler( final CellContextMenu cellContextMenu,
                                                                       final RowContextMenu rowContextMenu ) {
            this.cellContextMenu = cellContextMenu;
            this.rowContextMenu = rowContextMenu;
        }

        @Override
        public void onMouseDown( final MouseDownEvent event ) {
            if ( !eventTargetsPopup( event.getNativeEvent(),
                                     cellContextMenu.asWidget().getElement() ) ) {
                cellContextMenu.hide();
            }
            if ( !eventTargetsPopup( event.getNativeEvent(),
                                     rowContextMenu.asWidget().getElement() ) ) {
                rowContextMenu.hide();
            }
        }

        private boolean eventTargetsPopup( final NativeEvent event,
                                           final Element element ) {
            final EventTarget target = event.getEventTarget();
            if ( Element.is( target ) ) {
                return element.isOrHasChild( Element.as( target ) );
            }
            return false;
        }

    }

}