/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.apache.jmeter.testbeans.gui;

import java.awt.BorderLayout;
import java.awt.Component;
import java.beans.BeanDescriptor;
import java.beans.BeanInfo;
import java.beans.Customizer;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.beans.PropertyEditorManager;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.ResourceBundle;

import javax.swing.JPopupMenu;

import org.apache.commons.collections.map.LRUMap;
import org.apache.jmeter.assertions.Assertion;
import org.apache.jmeter.assertions.gui.AbstractAssertionGui;
import org.apache.jmeter.config.ConfigElement;
import org.apache.jmeter.config.gui.AbstractConfigGui;
import org.apache.jmeter.control.Controller;
import org.apache.jmeter.control.gui.AbstractControllerGui;
import org.apache.jmeter.gui.AbstractJMeterGuiComponent;
import org.apache.jmeter.gui.JMeterGUIComponent;
import org.apache.jmeter.gui.util.MenuFactory;
import org.apache.jmeter.processor.PostProcessor;
import org.apache.jmeter.processor.PreProcessor;
import org.apache.jmeter.processor.gui.AbstractPostProcessorGui;
import org.apache.jmeter.processor.gui.AbstractPreProcessorGui;
import org.apache.jmeter.samplers.Sampler;
import org.apache.jmeter.samplers.gui.AbstractSamplerGui;
import org.apache.jmeter.testbeans.TestBean;
import org.apache.jmeter.testelement.TestElement;
import org.apache.jmeter.testelement.property.AbstractProperty;
import org.apache.jmeter.testelement.property.JMeterProperty;
import org.apache.jmeter.testelement.property.PropertyIterator;
import org.apache.jmeter.timers.Timer;
import org.apache.jmeter.timers.gui.AbstractTimerGui;
import org.apache.jmeter.util.JMeterUtils;
import org.apache.jmeter.util.LocaleChangeEvent;
import org.apache.jmeter.util.LocaleChangeListener;
import org.apache.jmeter.visualizers.Visualizer;
import org.apache.jmeter.visualizers.gui.AbstractVisualizer;
import org.apache.jorphan.util.JOrphanUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * JMeter GUI element editing for TestBean elements.
 * <p>
 * The actual GUI is always a bean customizer: if the bean descriptor provides
 * one, it will be used; otherwise, a GenericTestBeanCustomizer will be created
 * for this purpose.
 * <p>
 * Those customizers deviate from the standards only in that, instead of a bean,
 * they will receive a Map in the setObject call. This will be a property name
 * to value Map. The customizer is also in charge of initializing empty Maps
 * with sensible initial values.
 * <p>
 * If the provided Customizer class implements the SharedCustomizer interface,
 * the same instance of the customizer will be reused for all beans of the type:
 * setObject(map) can then be called multiple times. Otherwise, one separate
 * instance will be used for each element. For efficiency reasons, most
 * customizers should implement SharedCustomizer.
 *
 */
public class TestBeanGUI extends AbstractJMeterGuiComponent implements JMeterGUIComponent, LocaleChangeListener{
    private static final long serialVersionUID = 241L;

    private static final Logger log = LoggerFactory.getLogger(TestBeanGUI.class);

    private final Class<?> testBeanClass;
    private transient BeanInfo beanInfo;
    private final Class<?> customizerClass;

    /**
     * The single customizer if the customizer class implements
     * SharedCustomizer, null otherwise.
     */
    private Customizer customizer = null;

    /**
     * TestElement to Customizer map if customizer is null. This is necessary to
     * avoid the cost of creating a new customizer on each edit. The cache size
     * needs to be limited, though, to avoid memory issues when editing very
     * large test plans.
     */
    @SuppressWarnings("unchecked")
    private final Map<TestElement, Customizer> customizers = new LRUMap(20);

    /** Index of the customizer in the JPanel's child component list: */
    private int customizerIndexInPanel;

    /** The property name to value map that the active customizer edits: */
    private final Map<String, Object> propertyMap = new HashMap<>();

    /** Whether the GUI components have been created. */
    private boolean initialized = false;

    static {
        List<String> paths = new LinkedList<>();
        paths.add("org.apache.jmeter.testbeans.gui");// $NON-NLS-1$
        paths.addAll(Arrays.asList(PropertyEditorManager.getEditorSearchPath()));
        String s = JMeterUtils.getPropDefault("propertyEditorSearchPath", null);// $NON-NLS-1$
        if (s != null) {
            paths.addAll(Arrays.asList(JOrphanUtils.split(s, ",", "")));// $NON-NLS-1$ // $NON-NLS-2$
        }
        PropertyEditorManager.setEditorSearchPath(paths.toArray(new String[paths.size()]));
    }

    /**
     * @deprecated Dummy for JUnit test purposes only
     */
    @Deprecated
    public TestBeanGUI() {
        log.warn("Constructor only for use in testing");// $NON-NLS-1$
        testBeanClass = null;
        customizerClass = null;
        beanInfo = null;
    }

    public TestBeanGUI(Class<?> testBeanClass) {
        super();
        log.debug("testing class: {}", testBeanClass);
        // A quick verification, just in case:
        if (!TestBean.class.isAssignableFrom(testBeanClass)) {
            Error e = new Error();
            log.error("This should never happen!", e);
            throw e; // Programming error: bail out.
        }

        this.testBeanClass = testBeanClass;

        // Get the beanInfo:
        try {
            beanInfo = Introspector.getBeanInfo(testBeanClass);
        } catch (IntrospectionException e) {
            log.error("Can't get beanInfo for {}", testBeanClass, e);
            throw new Error(e); // Programming error. Don't continue.
        }

        customizerClass = beanInfo.getBeanDescriptor().getCustomizerClass();

        // Creation of customizer and GUI initialization
        // is delayed until the first configure call.
        // It's not needed to find the static label, menu categories, etc.
        initialized = false;
        JMeterUtils.addLocaleChangeListener(this);
    }

    private Customizer createCustomizer() {
        try {
            return (Customizer) customizerClass.getDeclaredConstructor().newInstance();
        } catch (ReflectiveOperationException e) {
            log.error("Could not instantiate customizer of {}", customizerClass, e);
            throw new Error(e.toString());
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String getStaticLabel() {
        if (beanInfo == null){
            return "null";// $NON-NLS-1$
        }
        return beanInfo.getBeanDescriptor().getDisplayName();
    }

    /**
     * {@inheritDoc}
     */
   @Override
    public TestElement createTestElement() {
        try {
            TestElement element = (TestElement) testBeanClass.getDeclaredConstructor().newInstance();
            // In other GUI component, clearGUI resets the value to defaults one as there is one GUI per Element
            // With TestBeanGUI as it's shared, its default values are only known here, we must call setValues with 
            // element (as it holds default values)
            // otherwise we will get values as computed by customizer reset and not default ones
            if (initialized) {
                setValues(element);
            }
            // put the default values back into the new element
            modifyTestElement(element);
            return element;
        } catch (ReflectiveOperationException e) {
            log.error("Can't create test element", e);
            throw new Error(e); // Programming error. Don't continue.
        }
    }

   /**
    * {@inheritDoc}
    */
    @Override
    public void modifyTestElement(TestElement element) {
        // Fetch data from screen fields
        if (customizer instanceof GenericTestBeanCustomizer) {
            GenericTestBeanCustomizer gtbc = (GenericTestBeanCustomizer) customizer;
            gtbc.saveGuiFields();
        }
        configureTestElement(element);

        // Copy all property values from the map into the element:
        for (PropertyDescriptor desc : beanInfo.getPropertyDescriptors()) {
            String name = desc.getName();
            Object value = propertyMap.get(name);
            log.debug("Modify {} to {}", name, value);
            if (value == null) {
                if (GenericTestBeanCustomizer.notNull(desc)) { // cannot be null
                    if (GenericTestBeanCustomizer.noSaveDefault(desc)) {
                        log.debug("Did not set DEFAULT for {}", name);
                        element.removeProperty(name);
                    } else {
                        setPropertyInElement(element, name, desc.getValue(GenericTestBeanCustomizer.DEFAULT));
                    }
                } else {
                    element.removeProperty(name);
                }
            } else {
                if (GenericTestBeanCustomizer.noSaveDefault(desc) && value.equals(desc.getValue(GenericTestBeanCustomizer.DEFAULT))) {
                    log.debug("Did not set {} to the default: {}", name, value);
                    element.removeProperty(name);
                } else {
                    setPropertyInElement(element, name, value);
                }
            }
        }
    }

    /**
     * @param element
     * @param name
     */
    private void setPropertyInElement(TestElement element, String name, Object value) {
        JMeterProperty jprop = AbstractProperty.createProperty(value);
        jprop.setName(name);
        element.setProperty(jprop);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public JPopupMenu createPopupMenu() {
        if (Timer.class.isAssignableFrom(testBeanClass)) {
            return MenuFactory.getDefaultTimerMenu();
        } else if (Sampler.class.isAssignableFrom(testBeanClass)) {
            return MenuFactory.getDefaultSamplerMenu();
        } else if (ConfigElement.class.isAssignableFrom(testBeanClass)) {
            return MenuFactory.getDefaultConfigElementMenu();
        } else if (Assertion.class.isAssignableFrom(testBeanClass)) {
            return MenuFactory.getDefaultAssertionMenu();
        } else if (PostProcessor.class.isAssignableFrom(testBeanClass)
                || PreProcessor.class.isAssignableFrom(testBeanClass)) {
            return MenuFactory.getDefaultExtractorMenu();
        } else if (Visualizer.class.isAssignableFrom(testBeanClass)) {
            return MenuFactory.getDefaultVisualizerMenu();
        } else if (Controller.class.isAssignableFrom(testBeanClass)) {
            return MenuFactory.getDefaultControllerMenu();
        } else {
            log.warn("Cannot determine PopupMenu for {}", testBeanClass);
            return MenuFactory.getDefaultMenu();
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void configure(TestElement element) {
        if (!initialized){
            init();
        }
        clearGui();
        super.configure(element);
        setValues(element);
        initialized = true;
    }
    
    /**
     * Get values from element to fill propertyMap and setup customizer 
     * @param element TestElement
     */
    private void setValues(TestElement element) {
        // Copy all property values into the map:
        for (PropertyIterator jprops = element.propertyIterator(); jprops.hasNext();) {
            JMeterProperty jprop = jprops.next();
            propertyMap.put(jprop.getName(), jprop.getObjectValue());
        }
        
        if (customizer != null) {
            customizer.setObject(propertyMap);
        } else {
            if (initialized){
                remove(customizerIndexInPanel);
            }
            Customizer c = customizers.get(element);
            if (c == null) {
                c = createCustomizer();
                c.setObject(propertyMap);
                customizers.put(element, c);
            }
            add((Component) c, BorderLayout.CENTER);
        }
    }

    /** {@inheritDoc} */
    @Override
    public Collection<String> getMenuCategories() {
        BeanDescriptor bd = beanInfo.getBeanDescriptor();

        // Don't show expert beans in the menus unless we're in expert mode
        if (bd.isExpert() && !JMeterUtils.isExpertMode()) {
            return null;
        }

        List<String> menuCategories = setupGuiClassesList();
        if (menuCategories.isEmpty()) {
            log.error("Could not assign GUI class to {}", testBeanClass);
        } else if (menuCategories.size() > 1) {
            // A TestBean implementation might implement 
            // different TestElement interfaces without being a problem
            log.info("More than 1 GUI class found for {}", testBeanClass);
        }
        return menuCategories;
    }

    /**
     * Setup GUI class
     *
     * @return number of matches
     */
    public int setupGuiClasses() {
        return setupGuiClassesList().size();
    }
    
    /**
     * Setup GUI class
     *
     * @return matches
     */
    private List<String> setupGuiClassesList() {
        List<String> menuCategories = new ArrayList<>();
        // TODO: there must be a nicer way...
        BeanDescriptor bd = beanInfo.getBeanDescriptor();
        if (Assertion.class.isAssignableFrom(testBeanClass)) {
            menuCategories.add(MenuFactory.ASSERTIONS);
            bd.setValue(TestElement.GUI_CLASS, AbstractAssertionGui.class.getName());
        }
        if (ConfigElement.class.isAssignableFrom(testBeanClass)) {
            menuCategories.add(MenuFactory.CONFIG_ELEMENTS);
            bd.setValue(TestElement.GUI_CLASS, AbstractConfigGui.class.getName());
        }
        if (Controller.class.isAssignableFrom(testBeanClass)) {
            menuCategories.add(MenuFactory.CONTROLLERS);
            bd.setValue(TestElement.GUI_CLASS, AbstractControllerGui.class.getName());
        }
        if (Visualizer.class.isAssignableFrom(testBeanClass)) {
            menuCategories.add(MenuFactory.LISTENERS);
            bd.setValue(TestElement.GUI_CLASS, AbstractVisualizer.class.getName());
        }
        if (PostProcessor.class.isAssignableFrom(testBeanClass)) {
            menuCategories.add(MenuFactory.POST_PROCESSORS);
            bd.setValue(TestElement.GUI_CLASS, AbstractPostProcessorGui.class.getName());
        }
        if (PreProcessor.class.isAssignableFrom(testBeanClass)) {
            menuCategories.add(MenuFactory.PRE_PROCESSORS);
            bd.setValue(TestElement.GUI_CLASS, AbstractPreProcessorGui.class.getName());
        }
        if (Sampler.class.isAssignableFrom(testBeanClass)) {
            menuCategories.add(MenuFactory.SAMPLERS);
            bd.setValue(TestElement.GUI_CLASS, AbstractSamplerGui.class.getName());
        }
        if (Timer.class.isAssignableFrom(testBeanClass)) {
            menuCategories.add(MenuFactory.TIMERS);
            bd.setValue(TestElement.GUI_CLASS, AbstractTimerGui.class.getName());
        }
        return menuCategories;
    }

    private void init() {
        setLayout(new BorderLayout(0, 5));

        setBorder(makeBorder());
        add(makeTitlePanel(), BorderLayout.NORTH);

        customizerIndexInPanel = getComponentCount();

        if (customizerClass == null) {
            customizer = new GenericTestBeanCustomizer(beanInfo);
        } else if (SharedCustomizer.class.isAssignableFrom(customizerClass)) {
            customizer = createCustomizer();
        }

        if (customizer != null){
            add((Component) customizer, BorderLayout.CENTER);
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String getLabelResource() {
        // @see getStaticLabel
        return null;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void clearGui() {
        super.clearGui();
        if (customizer instanceof GenericTestBeanCustomizer) {
            GenericTestBeanCustomizer gtbc = (GenericTestBeanCustomizer) customizer;
            gtbc.clearGuiFields();
        }
        propertyMap.clear();
    }

    public boolean isHidden() {
        return beanInfo.getBeanDescriptor().isHidden();
    }

    public boolean isExpert() {
        return beanInfo.getBeanDescriptor().isExpert();
    }

    /**
     * Handle Locale Change by reloading BeanInfo
     * @param event {@link LocaleChangeEvent}
     */
    @Override
    public void localeChanged(LocaleChangeEvent event) {
        try {
            beanInfo = Introspector.getBeanInfo(testBeanClass);
            setupGuiClasses();
        } catch (IntrospectionException e) {
            log.error("Can't get beanInfo for {}", testBeanClass, e);
            JMeterUtils.reportErrorToUser("Can't get beanInfo for " + testBeanClass.getName());
        }
    }

    /**
     * {@inheritDoc}}
     * @see org.apache.jmeter.gui.AbstractJMeterGuiComponent#getDocAnchor()
     */
    @Override
    public String getDocAnchor() {
        ResourceBundle resourceBundle = ResourceBundle.getBundle(
                testBeanClass.getName() + "Resources",  // $NON-NLS-1$
                new Locale("",""));

        String name = resourceBundle.getString("displayName");
        return name.replace(' ', '_');
    }
}
