content: /*
   * This library is part of OpenCms -
   * the Open Source Content Management System
   *
   * Copyright (c) Alkacon Software GmbH & Co. KG (https://www.alkacon.com)
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   * Lesser General Public License for more details.
   *
   * For further information about Alkacon Software, please see the
   * company website: https://www.alkacon.com
   *
   * For further information about OpenCms, please see the
   * project website: https://www.opencms.org
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   */
  
  package org.opencms.gwt.client.ui.input;
  
  import org.opencms.gwt.client.I_CmsHasInit;
  import org.opencms.gwt.client.Messages;
  import org.opencms.gwt.client.ui.I_CmsAutoHider;
  import org.opencms.gwt.client.ui.css.I_CmsInputLayoutBundle;
  import org.opencms.gwt.client.ui.input.form.CmsWidgetFactoryRegistry;
  import org.opencms.gwt.client.ui.input.form.I_CmsFormWidgetFactory;
  import org.opencms.gwt.client.util.CmsMessages;
  
  import org.opencms.util.CmsStringUtil;
  
  import java.util.HashMap;
  import java.util.Map;
  
  import com.google.common.base.Optional;
  import com.google.gwt.event.dom.client.BlurEvent;
  import com.google.gwt.event.dom.client.BlurHandler;
  import com.google.gwt.event.dom.client.ClickEvent;
  import com.google.gwt.event.dom.client.ClickHandler;
  import com.google.gwt.event.dom.client.FocusEvent;
  import com.google.gwt.event.dom.client.FocusHandler;
  import com.google.gwt.event.logical.shared.ValueChangeHandler;
  import com.google.gwt.event.shared.HandlerRegistration;
  import com.google.gwt.user.client.ui.FocusPanel;
  import com.google.gwt.user.client.ui.Panel;
  import com.google.gwt.user.client.ui.SimplePanel;
  import com.google.gwt.user.client.ui.TextBox;
  
  /**
   * Widget for selecting one of multiple items from a drop-down list which opens
   * after the user clicks on the widget.<p>
   *
   * @since 8.0.0
   *
   */
  public class CmsComboBox extends A_CmsSelectBox<CmsLabelSelectCell> implements I_CmsHasInit, I_CmsHasGhostValue {
  
      /** The key for the text which should be displayed in the opener if no option is available. */
      public static final String NO_SELECTION_OPENER_TEXT = "%NO_SELECTION_OPENER_TEXT%";
  
      /** The key for the text which should be displayed if no option is available. */
      public static final String NO_SELECTION_TEXT = "%NO_SELECTION_TEXT%";
  
      /** The widget type identifier. */
      private static final String WIDGET_TYPE = "combo";
  
      /** CSS style name for combo boxes. */
      public static final String CSS_CLASS = I_CmsInputLayoutBundle.INSTANCE.inputCss().comboBox();
  
      /** The ghost value. */
      protected String m_ghostValue;
  
      /** The widget displayed in the opener. */
      protected CmsSimpleTextBox m_openerWidget;
  
      /** The fade panel of this input box. */
      Panel m_fadePanel;
  
      /** A map from select options to their label texts. */
      private Map<String, String> m_items;
  
      /** The inner main panel for the input box. */
      private Panel m_mainPanel;
  
      /** The text which should be displayed in the opener if there is no selection. */
      private String m_noSelectionOpenerText;
  
      /** The text which should be displayed if there is no selection. */
      private String m_noSelectionText;
  
      /** A map of titles for the select options which should  be displayed on mouseover. */
      private Map<String, String> m_titles = new HashMap<String, String>();
  
      /**
       * Default constructor.<p>
       */
      public CmsComboBox() {
  
          super();
          addStyleName(CSS_CLASS);
  
      }
  
      /**
       * Constructs a new select box from a map.<p>
       *
       * The keys of the map are the values of the select options, and the values of the map are the labels to be displayed
       * for each option.
       *
       * @param items the map of select options
       */
      public CmsComboBox(Map<String, String> items) {
  
          this();
          setItems(items);
      }
  
      /**
       * Creates a new select box, with the option of adding a "not selected" choice.<p>
       *
       * @param items the map of select options
       * @param addNullOption if true, a "not selected" option will be added to the select box
       */
      public CmsComboBox(Map<String, String> items, boolean addNullOption) {
  
          super();
          addStyleName(CSS_CLASS);
          String resizable = items.remove(CmsSelectBox.OPTION_RESIZABLE);
          if ((resizable != null) && Boolean.FALSE.toString().equals(resizable)) {
              setPopupResize(false);
          }
  
          if (items.containsKey(NO_SELECTION_TEXT)) {
              m_noSelectionText = items.get(NO_SELECTION_TEXT);
              m_noSelectionOpenerText = items.get(NO_SELECTION_OPENER_TEXT);
              if (m_noSelectionOpenerText == null) {
                  m_noSelectionOpenerText = m_noSelectionText;
              }
              items.remove(NO_SELECTION_TEXT);
              items.remove(NO_SELECTION_OPENER_TEXT);
          }
          if (addNullOption) {
              String text = Messages.get().key(Messages.GUI_SELECTBOX_EMPTY_SELECTION_0);
              items.put("", text);
          }
          setItems(items);
          if (addNullOption) {
              selectValue("");
          }
      }
  
      /**
       * Initializes this class.<p>
       */
      public static void initClass() {
  
          // registers a factory for creating new instances of this widget
          CmsWidgetFactoryRegistry.instance().registerFactory(WIDGET_TYPE, new I_CmsFormWidgetFactory() {
  
              /**
               * @see org.opencms.gwt.client.ui.input.form.I_CmsFormWidgetFactory#createWidget(java.util.Map, com.google.common.base.Optional)
               */
              public I_CmsFormWidget createWidget(Map<String, String> widgetParams, Optional<String> defaultValue) {
  
                  return new CmsComboBox(widgetParams, false);
              }
          });
      }
  
      /**
       * Adds a new selection cell.<p>
       *
       * @param value the value of the select option
       * @param text the text to be displayed for the select option
       */
      public void addOption(String value, String text) {
  
          String title = getTitle(value, text);
          CmsLabelSelectCell cell = new CmsLabelSelectCell(value, text, title);
          addOption(cell);
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.A_CmsSelectBox#addValueChangeHandler(com.google.gwt.event.logical.shared.ValueChangeHandler)
       */
      @Override
      public HandlerRegistration addValueChangeHandler(ValueChangeHandler<String> handler) {
  
          return m_openerWidget.addValueChangeHandler(handler);
      }
  
      /**
       *
       */
      public void closeSelector() {
  
          close();
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.I_CmsFormWidget#getApparentValue()
       */
      public String getApparentValue() {
  
          String val = getFormValueAsString();
          if (val == null) {
              val = m_ghostValue;
          }
          return val;
  
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.I_CmsFormWidget#getFormValue()
       */
      @Override
      public Object getFormValue() {
  
          if (m_openerWidget.getText() == null) {
              return "";
          }
          return m_openerWidget.getText();
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.I_CmsFormWidget#getFormValueAsString()
       */
      @Override
      public String getFormValueAsString() {
  
          return (String)getFormValue();
      }
  
      /**
       * Returns the mainpanel of this widget.<p>
       *
       * @return the mainpanel of this widget
       */
      public Panel getMainPanel() {
  
          return m_mainPanel;
      }
  
      /**
       * Returns the opener of this widget.<p>
       *
       * @return the opener of this widget
       */
      public FocusPanel getOpener() {
  
          return m_opener;
      }
  
      /**
       * Returns the text box of this widget.<p>
       *
       *  @return the text box of this widget
       */
      public TextBox getTextBox() {
  
          return m_openerWidget;
      }
  
      /***/
      public void openSelector() {
  
          open();
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.A_CmsSelectBox#selectValue(java.lang.String)
       */
      @Override
      public void selectValue(String value) {
  
          super.selectValue(value);
          updateStyle();
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.I_CmsFormWidget#setAutoHideParent(org.opencms.gwt.client.ui.I_CmsAutoHider)
       */
      public void setAutoHideParent(I_CmsAutoHider autoHideParent) {
  
          // nothing to do
  
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.A_CmsSelectBox#setFormValue(java.lang.Object)
       */
      @Override
      public void setFormValue(Object value) {
  
          if (value == null) {
              value = "";
          }
  
          if (value instanceof String) {
              String strValue = (String)value;
              if (m_selectCells.containsKey(value)) {
                  selectValue(strValue);
                  onValueSelect(strValue);
              } else {
                  m_openerWidget.setText(strValue);
                  m_openerWidget.getElement().setTitle(strValue);
              }
  
          }
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.I_CmsFormWidget#setFormValueAsString(java.lang.String)
       */
      @Override
      public void setFormValueAsString(String formValue) {
  
          setFormValue(formValue);
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.I_CmsHasGhostValue#setGhostMode(boolean)
       */
      public void setGhostMode(boolean ghostMode) {
  
          // do nothing for now
  
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.I_CmsHasGhostValue#setGhostValue(java.lang.String, boolean)
       */
      public void setGhostValue(String value, boolean ghostMode) {
  
          if (value == null) {
              value = "";
          }
          String otherOptionText = m_items.get(value);
          String message = m_noSelectionText != null
          ? m_noSelectionText
          : Messages.get().key(Messages.GUI_SELECTBOX_EMPTY_SELECTION_1);
          message = CmsMessages.formatMessage(message, otherOptionText);
          m_ghostValue = value;
          updateCells();
          if (ghostMode) {
              selectValue("");
          }
      }
  
      /**
       * Sets the items using a map from option values to label texts.<p>
       *
       * @param items the map containing the select options
       */
      public void setItems(Map<String, String> items) {
  
          clearItems();
          m_items = items;
          for (Map.Entry<String, String> entry : items.entrySet()) {
              addOption(entry.getKey(), entry.getValue());
          }
      }
  
      /**
       * Sets the title for a select option.<p>
       *
       * Note: This will only affect select options added *after* calling this method!
       *
       * @param text the new title for the option
       */
      public void setText(String text) {
  
          m_openerWidget.setText(text);
      }
  
      /**
       * Sets the text that is used for the "not selected" option.<p>
       *
       * @param text the text which should be used for the "not selected" option
       */
      public void setTextForNullSelection(String text) {
  
          // do nothing if there's no null option
          CmsLabelSelectCell cell = m_selectCells.get("");
          if (cell == null) {
              return;
          }
          cell.setText(text);
          // if the null option is selected, we still need to update the opener
          if (CmsStringUtil.isEmptyOrWhitespaceOnly(m_selectedValue)) {
              selectValue("");
          }
      }
  
      /**
       * Sets the title for a select option.<p>
       *
       * Note: This will only affect select options added *after* calling this method!
       *
       * @param option the select option value
       * @param title the new title for the option
       */
      public void setTitle(String option, String title) {
  
          m_titles.put(option, title);
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.A_CmsSelectBox#truncateOpener(java.lang.String, int)
       */
      @Override
      public void truncateOpener(String prefix, int width) {
  
          //m_openerWidget.truncate(prefix + '_' + TM_OPENER_LABEL, width);
      }
  
      /**
       * Updates the select cells.<p>
       */
      public void updateCells() {
  
          for (CmsLabelSelectCell cell : m_selectCells.values()) {
              updateCell(cell);
          }
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.A_CmsSelectBox#createUnknownOption(java.lang.String)
       */
      @Override
      protected CmsLabelSelectCell createUnknownOption(String value) {
  
          CmsLabelSelectCell cell = new CmsLabelSelectCell(value, value);
          return cell;
  
      }
  
      /**
       * Helper method to get the title for a given select option.<p>
       *
       * @param option the select option value
       * @param defaultValue the value to return when no title for the value was found
       *
       * @return the title for the select option
       */
      protected String getTitle(String option, String defaultValue) {
  
          if ((option != null) && m_titles.containsKey(option)) {
              return m_titles.get(option);
          }
          return defaultValue;
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.A_CmsSelectBox#initOpener()
       */
      @Override
      protected void initOpener() {
  
          m_mainPanel = new SimplePanel();
          m_fadePanel = new SimplePanel();
          m_openerWidget = new CmsSimpleTextBox();
          m_panel.add(m_fadePanel);
  
          m_openerWidget.addBlurHandler(new BlurHandler() {
  
              public void onBlur(BlurEvent event) {
  
                  m_panel.add(m_fadePanel);
                  m_openerWidget.getElement().setTitle(m_openerWidget.getText());
              }
          });
          m_openerWidget.addFocusHandler(new FocusHandler() {
  
              public void onFocus(FocusEvent event) {
  
                  // on focus remove the fader.
                  m_panel.remove(m_fadePanel);
                  m_openerWidget.getElement().setTitle("");
  
              }
          });
  
          m_mainPanel.setStyleName(CSS.comboBoxOpener());
          m_fadePanel.addDomHandler(new ClickHandler() {
  
              public void onClick(ClickEvent event) {
  
                  m_openerWidget.setFocus(true);
                  m_openerWidget.setCursorPos(m_openerWidget.getText().length());
  
                  if (m_popup.isShowing()) {
                      close();
                  } else {
                      open();
                  }
  
              }
          }, ClickEvent.getType());
          m_fadePanel.setStyleName(CSS.fader());
          m_mainPanel.add(m_openerWidget);
          m_opener.add(m_mainPanel);
  
      }
  
      /**
       * @see com.google.gwt.user.client.ui.Widget#onLoad()
       */
      @Override
      protected void onLoad() {
  
          super.onLoad();
          updateStyle();
      }
  
      /**
       * Updates the select cell.<p>
       *
       * @param cell the select cell
       */
      protected void updateCell(CmsLabelSelectCell cell) {
          // do nothing
  
      }
  
      /**
       * @see org.opencms.gwt.client.ui.input.A_CmsSelectBox#updateOpener(java.lang.String)
       */
      @Override
      protected void updateOpener(String newValue) {
  
          CmsLabelSelectCell cell = m_selectCells.get(newValue);
          String openerText = cell.getOpenerText();
          m_openerWidget.setTitle(openerText);
          m_openerWidget.setValue(newValue, true);
      }
  
      /**
       * This method should be used to make changes to the CSS style of the select box when the value changes.<p>
       */
      protected void updateStyle() {
  
          // do nothing
  
      }
  
  }
  