/**
 * @file lldraghandle.h
 * @brief LLDragHandle base class
 *
 * $LicenseInfo:firstyear=2001&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * 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;
 * version 2.1 of the License only.
 *
 * 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.
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

// A widget for dragging a view around the screen using the mouse.

#ifndef LL_DRAGHANDLE_H
#define LL_DRAGHANDLE_H

#include "llview.h"
#include "v4color.h"
#include "llrect.h"
#include "llcoord.h"

class LLTextBox;

class LLDragHandle : public LLView
{
public:
    struct Params
    :   public LLInitParam::Block<Params, LLView::Params>
    {
        Optional<std::string> label;
        Optional<LLUIColor> drag_highlight_color;
        Optional<LLUIColor> drag_shadow_color;

        Params()
        :   label("label"),
            drag_highlight_color("drag_highlight_color", LLUIColorTable::instance().getColor("DefaultHighlightLight")),
            drag_shadow_color("drag_shadow_color", LLUIColorTable::instance().getColor("DefaultShadowDark"))
        {
            changeDefault(mouse_opaque, true);
            changeDefault(follows.flags, FOLLOWS_ALL);
        }
    };
    void initFromParams(const Params&);

    virtual ~LLDragHandle();

    virtual void setValue(const LLSD& value);

    void            setForeground(bool b)       { mForeground = b; }
    bool            getForeground() const       { return mForeground; }
    void            setMaxTitleWidth(S32 max_width) {mMaxTitleWidth = llmin(max_width, mMaxTitleWidth); }
    S32             getMaxTitleWidth() const { return mMaxTitleWidth; }
    void            setButtonsRect(const LLRect& rect){ mButtonsRect = rect; }
    LLRect          getButtonsRect() const { return mButtonsRect; }
    void            setTitleVisible(bool visible);

    virtual void    setTitle( const std::string& title ) = 0;
    virtual std::string getTitle() const = 0;

    virtual bool    handleHover(S32 x, S32 y, MASK mask);
    virtual bool    handleMouseDown(S32 x, S32 y, MASK mask);
    virtual bool    handleMouseUp(S32 x, S32 y, MASK mask);

protected:
    LLDragHandle(const Params&);
    friend class LLUICtrlFactory;

protected:
    LLTextBox*      mTitleBox;

private:
    LLRect          mButtonsRect;
    S32             mDragLastScreenX;
    S32             mDragLastScreenY;
    S32             mLastMouseScreenX;
    S32             mLastMouseScreenY;
    LLCoordGL       mLastMouseDir;
    LLUIColor       mDragHighlightColor;
    LLUIColor       mDragShadowColor;
    S32             mMaxTitleWidth;
    bool            mForeground;

    // Pixels near the edge to snap floaters.
    static S32      sSnapMargin;
};


// Use this one for traditional top-of-window draggers
class LLDragHandleTop
: public LLDragHandle
{
protected:
    LLDragHandleTop(const Params& p) : LLDragHandle(p) {}
    friend class LLUICtrlFactory;
public:
    virtual void    setTitle( const std::string& title );
    virtual std::string getTitle() const;
    virtual void    draw();
    virtual void    reshape(S32 width, S32 height, bool called_from_parent = true);

private:
    void    reshapeTitleBox();
};


// Use this for left-side, vertical text draggers
class LLDragHandleLeft
: public LLDragHandle
{
protected:
    LLDragHandleLeft(const Params& p) : LLDragHandle(p) {}
    friend class LLUICtrlFactory;
public:
    virtual void    setTitle( const std::string& title );
    virtual std::string getTitle() const;
    virtual void    draw();
    virtual void    reshape(S32 width, S32 height, bool called_from_parent = true);

};

const S32 DRAG_HANDLE_HEIGHT = 16;
const S32 DRAG_HANDLE_WIDTH = 16;

#endif  // LL_DRAGHANDLE_H