vaadin-framework/client/src/main/java/com/vaadin/client/debug/internal/HierarchySection.java

/*
 * Copyright 2000-2018 Vaadin Ltd.
 *
 * 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 com.vaadin.client.debug.internal;

import com.google.gwt.dom.client.Element;
import com.google.gwt.event.dom.client.KeyCodes;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.Event;
import com.google.gwt.user.client.Event.NativePreviewHandler;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.FlowPanel;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.SimplePanel;
import com.google.gwt.user.client.ui.Widget;
import com.vaadin.client.ApplicationConfiguration;
import com.vaadin.client.ApplicationConnection;
import com.vaadin.client.ComponentConnector;
import com.vaadin.client.ServerConnector;
import com.vaadin.client.Util;
import com.vaadin.client.ValueMap;
import com.vaadin.client.WidgetUtil;

/**
 * Provides functionality for examining the UI component hierarchy.
 *
 * @since 7.1
 * @author Vaadin Ltd
 */
public class HierarchySection implements Section {
    private final DebugButton tabButton = new DebugButton(Icon.HIERARCHY,
            "Examine component hierarchy");

    private final SimplePanel content = new SimplePanel();

    // TODO highlighting logic is split between these, should be refactored
    private final FlowPanel helpPanel = new FlowPanel();
    private final ConnectorInfoPanel infoPanel = new ConnectorInfoPanel();
    private final HierarchyPanel hierarchyPanel = new HierarchyPanel();
    private final OptimizedWidgetsetPanel widgetsetPanel = new OptimizedWidgetsetPanel();
    private final AnalyzeLayoutsPanel analyzeLayoutsPanel = new AnalyzeLayoutsPanel();

    private final FlowPanel controls = new FlowPanel();

    private final Button find = new DebugButton(Icon.HIGHLIGHT,
            "Select a component on the page to inspect it");
    private final Button analyze = new DebugButton(Icon.ANALYZE,
            "Check layouts for potential problems");
    private final Button generateWS = new DebugButton(Icon.OPTIMIZE,
            "Show used connectors and how to optimize widgetset");
    private final Button showHierarchy = new DebugButton(Icon.HIERARCHY,
            "Show the connector hierarchy tree");
    private final Button generateDesign = new DebugButton(Icon.SHOW_DESIGN,
            "Generate a declarative design for the given component sub tree");

    private HandlerRegistration highlightModeRegistration = null;

    public interface FindHandler {

        /**
         * Called when the user hovers over a connector, which is highlighted.
         * Also called when hovering outside the tree, e.g. over the debug
         * console, but in this case the connector is null
         *
         * @param connector
         */
        void onHover(ComponentConnector connector);

        /**
         * Called when the user clicks on a highlighted connector.
         *
         * @param connector
         */
        void onSelected(ComponentConnector connector);

    }

    private FindHandler inspectComponent = new FindHandler() {

        @Override
        public void onHover(ComponentConnector connector) {
            if (connector == null) {
                infoPanel.clear();
            } else {
                printState(connector, false);
            }
        }

        @Override
        public void onSelected(ComponentConnector connector) {
            stopFind();
            printState(connector, true);
        }

    };
    private FindHandler showComponentDesign = new FindHandler() {

        @Override
        public void onHover(ComponentConnector connector) {
            Highlight.showOnly(connector);
        }

        @Override
        public void onSelected(ComponentConnector connector) {
            stopFind();
            connector.getConnection().getUIConnector()
                    .showServerDesign(connector);
            content.setWidget(
                    new HTML("Design file for component sent to server log"));
        }

    };

    private FindHandler activeFindHandler;

    public HierarchySection() {
        controls.add(showHierarchy);
        showHierarchy.setStylePrimaryName(VDebugWindow.STYLENAME_BUTTON);
        showHierarchy.addClickHandler(event -> showHierarchy());

        controls.add(find);
        find.setStylePrimaryName(VDebugWindow.STYLENAME_BUTTON);
        find.addClickHandler(event -> toggleFind(inspectComponent));

        controls.add(analyze);
        analyze.setStylePrimaryName(VDebugWindow.STYLENAME_BUTTON);
        analyze.addClickHandler(event -> {
            stopFind();
            analyzeLayouts();
        });

        controls.add(generateWS);
        generateWS.setStylePrimaryName(VDebugWindow.STYLENAME_BUTTON);
        generateWS.addClickHandler(event -> generateWidgetset());

        controls.add(generateDesign);
        generateDesign.setStylePrimaryName(VDebugWindow.STYLENAME_BUTTON);
        generateDesign.addClickHandler(event -> {
            content.setWidget(new HTML(
                    "Select a layout or component to generate the declarative design"));
            toggleFind(showComponentDesign);
        });

        hierarchyPanel.addListener(
                (connector, element) -> printState(connector, true));

        analyzeLayoutsPanel.addListener(
                (connector, element) -> printState(connector, true));

        content.setStylePrimaryName(VDebugWindow.STYLENAME + "-hierarchy");

        initializeHelpPanel();
        content.setWidget(helpPanel);
    }

    private void initializeHelpPanel() {
        HTML info = new HTML(showHierarchy.getHTML() + " "
                + showHierarchy.getTitle() + "<br/>" + find.getHTML() + " "
                + find.getTitle() + "<br/>" + analyze.getHTML() + " "
                + analyze.getTitle() + "<br/>" + generateWS.getHTML() + " "
                + generateWS.getTitle() + "<br/>" + generateDesign.getHTML()
                + " " + generateDesign.getTitle() + "<br/>");
        info.setStyleName(VDebugWindow.STYLENAME + "-info");
        helpPanel.add(info);
    }

    private void showHierarchy() {
        Highlight.hideAll();
        hierarchyPanel.update();
        content.setWidget(hierarchyPanel);
    }

    @Override
    public DebugButton getTabButton() {
        return tabButton;
    }

    @Override
    public Widget getControls() {
        return controls;
    }

    @Override
    public Widget getContent() {
        return content;
    }

    @Override
    public void show() {

    }

    @Override
    public void hide() {
        stopFind();
    }

    private void generateWidgetset() {
        widgetsetPanel.update();
        content.setWidget(widgetsetPanel);
    }

    private void analyzeLayouts() {
        analyzeLayoutsPanel.update();
        content.setWidget(analyzeLayoutsPanel);
    }

    @Override
    public void meta(ApplicationConnection ac, ValueMap meta) {
        // show the results of analyzeLayouts
        analyzeLayoutsPanel.meta(ac, meta);
    }

    @Override
    public void uidl(ApplicationConnection ac, ValueMap uidl) {
        // NOP
    }

    private boolean isFindMode(FindHandler handler) {
        return activeFindHandler == handler;
    }

    private boolean isFindMode() {
        return (activeFindHandler != null);
    }

    private void toggleFind(FindHandler handler) {
        if (isFindMode()) {
            // Currently finding something
            if (isFindMode(handler)) {
                // Toggle off, stop finding
                stopFind();
                return;
            } else {
                // Stop finding something else, start finding this
                stopFind();
                startFind(handler);
            }
        } else {
            // Not currently finding anything
            startFind(handler);
        }
    }

    private void startFind(FindHandler handler) {
        if (isFindMode()) {
            stopFind();
        }
        Highlight.hideAll();

        highlightModeRegistration = Event
                .addNativePreviewHandler(highlightModeHandler);
        activeFindHandler = handler;
        if (handler == inspectComponent) {
            find.addStyleDependentName(VDebugWindow.STYLENAME_ACTIVE);
        } else if (handler == showComponentDesign) {
            generateDesign.addStyleDependentName(VDebugWindow.STYLENAME_ACTIVE);
        }

    }

    /**
     * Stop any current find operation, regardless of the handler
     */
    private void stopFind() {
        if (!isFindMode()) {
            return;
        }

        highlightModeRegistration.removeHandler();
        highlightModeRegistration = null;
        find.removeStyleDependentName(VDebugWindow.STYLENAME_ACTIVE);
        generateDesign.removeStyleDependentName(VDebugWindow.STYLENAME_ACTIVE);
        activeFindHandler = null;
    }

    private void printState(ServerConnector connector, boolean serverDebug) {
        Highlight.showOnly(connector);
        if (serverDebug) {
            HierarchyPanel.showServerDebugInfo(connector);
        }

        infoPanel.update(connector);
        content.setWidget(infoPanel);
    }

    private final NativePreviewHandler highlightModeHandler = event -> {
        if (event.getTypeInt() == Event.ONKEYDOWN
                && event.getNativeEvent().getKeyCode() == KeyCodes.KEY_ESCAPE) {
            stopFind();
            Highlight.hideAll();
            return;
        }
        if (event.getTypeInt() == Event.ONMOUSEMOVE) {
            Highlight.hideAll();
            Element eventTarget = WidgetUtil.getElementFromPoint(
                    event.getNativeEvent().getClientX(),
                    event.getNativeEvent().getClientY());

            if (VDebugWindow.get().getElement().isOrHasChild(eventTarget)) {
                // Do not prevent using debug window controls
                infoPanel.clear();
                return;
            }

            for (ApplicationConnection a : ApplicationConfiguration
                    .getRunningApplications()) {
                ComponentConnector connector = Util.getConnectorForElement(a,
                        a.getUIConnector().getWidget(), eventTarget);
                if (connector == null) {
                    connector = Util.getConnectorForElement(a, RootPanel.get(),
                            eventTarget);
                }
                if (connector != null) {
                    activeFindHandler.onHover(connector);
                    event.cancel();
                    event.consume();
                    event.getNativeEvent().stopPropagation();
                    return;
                }
            }
            // Not over any connector
            activeFindHandler.onHover(null);
        }
        if (event.getTypeInt() == Event.ONCLICK) {
            Highlight.hideAll();
            event.cancel();
            event.consume();
            event.getNativeEvent().stopPropagation();
            Element eventTarget = WidgetUtil.getElementFromPoint(
                    event.getNativeEvent().getClientX(),
                    event.getNativeEvent().getClientY());
            for (ApplicationConnection a : ApplicationConfiguration
                    .getRunningApplications()) {
                ComponentConnector connector = Util.getConnectorForElement(a,
                        a.getUIConnector().getWidget(), eventTarget);
                if (connector == null) {
                    connector = Util.getConnectorForElement(a, RootPanel.get(),
                            eventTarget);
                }

                if (connector != null) {
                    activeFindHandler.onSelected(connector);
                    return;
                }
            }
            // Click on something else -> stop find operation
            stopFind();
        }
        event.cancel();
    };

}