// This may look like C code, but it's really -*- C++ -*-

/*

 * Copyright (C) 2008 Emweb bv, Herent, Belgium.

 *

 * See the LICENSE file for terms of use.

 */

#ifndef WINPLACE_EDIT_H_

#define WINPLACE_EDIT_H_

#include <Wt/WCompositeWidget.h>

namespace Wt {

class WText;

class WLineEdit;

class WPushButton;

/*! \class WInPlaceEdit Wt/WInPlaceEdit.h Wt/WInPlaceEdit.h

 *  \brief A widget that provides in-place-editable text.

 *

 * The %WInPlaceEdit provides a text that may be edited in place by

 * the user by clicking on it. When clicked, the text turns into a

 * line edit, with optionally a save and cancel button (see

 * setButtonsEnabled()).

 *

 * When the user saves the edit, the valueChanged() signal is emitted.

 *

 * Usage example:

 * \if cpp

 * \code

 * auto w = std::make_unique<Wt::WContainerWidget>();

 * w->addWidget(std::make_unique<Wt::WText>("Name: "));

 * w->addWidget(std::make_unique<Wt::WInPlaceEdit>("Bob Smith"));

 * edit->setStyleClass("inplace");

 * \endcode

 * \elseif java

 * \code

 * WContainerWidget w = new WContainerWidget();

 * new WText("Name: ", w);

 * WInPlaceEdit edit = new WInPlaceEdit("Bob Smith", w);

 * edit.setStyleClass("inplace");

 * \endcode

 * \endif

 *

 * This code will produce an edit that looks like:

 * \image html WInPlaceEdit-1.png "WInPlaceEdit text mode"

 * When the text is clicked, the edit will expand to become:

 * \image html WInPlaceEdit-2.png "WInPlaceEdit edit mode"

 *

 * <h3>CSS</h3>

 *

 * A WInPlaceEdit widget renders as a <tt>&lt;span&gt;</tt> containing

 * a WText, a WLineEdit and optional buttons (WPushButton). All these

 * widgets may be styled as such. It does not provide style information.

 *

 * In particular, you may want to provide a visual indication that the text

 * is editable e.g. using a hover effect:

 *

 * CSS stylesheet:

 * \code

 * .inplace span:hover {

 *    background-color: gray;

 * }

 * \endcode

 */

class WT_API WInPlaceEdit : public WCompositeWidget

{

public:

  /*! \brief Creates an in-place edit.

   */

  WInPlaceEdit();

  /*! \brief Creates an in-place edit with the given text.

   */

  WInPlaceEdit(const WString& text);

  /*! \brief Creates an in-place edit with the given text.

   *

   * The first parameter configures whether buttons are available in edit

   * mode.

   *

   * \sa setButtonsEnabled()

   */

  WInPlaceEdit(bool buttons, const WString& text);

  /*! \brief Returns the current value.

   *

   * \sa setText()

   */

  const WString& text() const;

  /*! \brief Sets the current value.

   *

   * \sa text()

   */

  void setText(const WString& text);

  /*! \brief Sets the placeholder text.

   *

   * This sets the text that is shown when the field is empty.

   */

  void setPlaceholderText(const WString& placeholder);

  /*! \brief Returns the placeholder text.

   *

   * \sa setPlaceholderText()

   */

  const WString& placeholderText() const;

  /*! \brief Returns the line edit.

   *

   * You may use this for example to set a validator on the line edit.

   */

  WLineEdit *lineEdit() const { return edit_; }

  /*! \brief Returns the WText widget that renders the current string.

   *

   * You may use this for example to set the text format of the displayed

   * string.

   */

  WText *textWidget() const { return text_; }

  /*! \brief Returns the save button.

   *

   * This method returns \c 0 if the buttons were disabled.

   *

   * \sa cancelButton(), setButtonsEnabled()

   */

  WPushButton *saveButton() const { return save_; }

  /*! \brief Returns the cancel button.

   *

   * This method returns \c 0 if the buttons were disabled.

   *

   * \sa saveButton(), setButtonsEnabled()

   */

  WPushButton *cancelButton() const { return cancel_; }

  /*! \brief %Signal emitted when the value has been changed.

   *

   * The signal argument provides the new value.

   */

  Signal<WString>& valueChanged() { return valueChanged_; }

  /*! \brief Displays the Save and 'Cancel' button during editing

   *

   * By default, the Save and Cancel buttons are shown. Call this

   * function with \p enabled = \c false to only show a line edit.

   *

   * In this mode, the enter key or any event that causes focus to be

   * lost saves the value while the escape key cancels the editing.

   */

  void setButtonsEnabled(bool enabled = true);

protected:

  virtual void render(WFlags<RenderFlag> flags) override;

private:

  void create();

  void save();

  void cancel();

private:

  Signal<WString> valueChanged_;

  WContainerWidget *impl_, *editing_, *buttons_;

  WText *text_;

  WLineEdit *edit_;

  WPushButton *save_, *cancel_;

  WString placeholderText_;

  Wt::Signals::connection c2_;

  bool empty_;

};

}

#endif // WINPLACE_EDIT_H_