/*
    Edit With Button

    This class acts mostly like a normal Edit Box except that it provides a button to the right
    side of the control. Clicking the button invokes the virutal OnLeftClick method. If that
    has not been overridden in a derived classes then it sends the EDIT_BUTTON_LEFTCLICKED
    message to the parent window.

    CEditWithButton_Base contains most of the code to make this work but cannot be instantiated
    itself. A derived class must override DrawButtonContent and CalculateButtonWidth to determine
    what is actually drawn for the button.

    CEditWithButton is a derived class that handles the simplest form of a button where a plain
    text string is displayed on the button.

    Other classes could be derived to draw other kinds of buttons.
*/
#pragma once

#include <afxwin.h>
#include "UxTheme.h"


// May be sent to the parent window when the edit control's button is clicked.
// wParam will be set to the ID of the control that sent the message.
#define EDIT_BUTTON_LEFTCLICKED     (WM_APP + 842)                  // arbitrary number, change if necessary


// CEditWithButton_Base ---------------------------------------------------------------------------
// This is the base class from which others derive to implement specific kinds of buttons.
class CEditWithButton_Base : public CEdit
{
public:
    CEditWithButton_Base();

    // Called when a left click is detected. The default implementation will send a
    // EDIT_BUTTON_LEFTCLICKED message to the parent window. Derived classes
    // could override this to handle the event themselves, and so are not required
    // to call this base implementation.
    virtual void OnLeftClick();

protected:
    afx_msg void OnNcCalcSize(BOOL bCalcValidRects, NCCALCSIZE_PARAMS* lpncsp);
    afx_msg void OnNcPaint();
    afx_msg void OnNcLButtonDown(UINT nHitTest, CPoint point);
    afx_msg void OnMouseMove(UINT nFlags, CPoint point);
    afx_msg void OnNcMouseMove(UINT nHitTest, CPoint point);
    afx_msg void OnNcMouseLeave();
    afx_msg void OnLButtonUp(UINT nFlags, CPoint point);
    afx_msg LRESULT OnNcHitTest(CPoint point);
    virtual void PreSubclassWindow();
    afx_msg LRESULT OnRecalcNcSize(WPARAM wParam, LPARAM lParam);
    afx_msg void OnEnable(BOOL bEnable);
    afx_msg LRESULT OnSetReadOnly(WPARAM wParam, LPARAM lParam);
    DECLARE_MESSAGE_MAP()

    // Given the rectangle of the control window, this returns the rect that the button will occupy.
    CRect GetButtonRect(const CRect& rectWindow) const;

    // Translates the current button state in a value that could be used by DrawThemeBackground.
    int GetButtonThemeState() const;

    //  Called when the button needs to be drawn.
    //  The default implementation draws the button frame, adjusts the rect if
    //  the button is pressed, and then calls DrawButtonContent to render the
    //  contents of the button.
    virtual void DrawButton(CRect rectButton);

    //  Called when the button contents (anything inside the button's border) needs to
    //  be drawn. The rect will have already been adjusted if the button is pressed.
    //  The content must be drawn using the given device context within the given rect.
    virtual void DrawButtonContent(CDC& dc, CRect rectButton, HTHEME hButtonTheme) = 0;

    //  Called when the button's width needs to be (re)calculated.
    //  This must return the width in pixels.
    virtual int CalculateButtonWidth() = 0;

private:

    int m_TopBorder;
    int m_BottomBorder;
    int m_LeftBorder;
    int m_RightBorder;

    int m_ButtonWidth;                  // stores the button's width in pixels (so that we don't have to re-calculate it)

    bool m_IsButtonPressed;
    bool m_IsMouseActive;

    bool m_IsButtonHot;
};


// CEditWithButton --------------------------------------------------------------------------------
// This implements a button containing plain text.
class CEditWithButton : public CEditWithButton_Base
{
public:
    // The given text will be displayed in the button.
    explicit CEditWithButton(LPCTSTR pszButtonText = _T("..."));

    // Gets/Sets the button text.
    CString GetButtonText() const;
    void SetButtonText(LPCTSTR buttonText);

private:

    virtual void DrawButtonContent(CDC& dc, CRect rectButton, HTHEME hButtonTheme);

    virtual int CalculateButtonWidth();

    CString m_ButtonText;
};