/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * The contents of this file are subject to the Netscape Public License
 * Version 1.0 (the "NPL"); you may not use this file except in
 * compliance with the NPL.  You may obtain a copy of the NPL at
 * http://www.mozilla.org/NPL/
 *
 * Software distributed under the NPL is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
 * for the specific language governing rights and limitations under the
 * NPL.
 *
 * The Initial Developer of this code under the NPL is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
 * Reserved.
 */

#include "nsScrollbar.h"
#include "nsIDeviceContext.h"

NS_IMPL_ADDREF(nsScrollbar);
NS_IMPL_RELEASE(nsScrollbar);

ControlActionUPP nsScrollbar::sControlActionProc = nsnull;

/**-------------------------------------------------------------------------------
 * nsScrollbar Constructor
 *	@update  dc 10/31/98
 * @param aIsVertical -- Tells if the scrollbar had a vertical or horizontal orientation
 */
nsScrollbar::nsScrollbar(PRBool /*aIsVertical*/)
	:	nsMacControl()
	,	nsIScrollbar()
	,	mLineIncrement(0)
	,	mFullImageSize(0)
	,	mVisibleImageSize(0)
	,	mMouseDownInScroll(PR_FALSE)
	,	mClickedPartCode(0)
{
	NS_INIT_REFCNT();
	strcpy(gInstanceClassName, "nsScrollbar");
	SetControlType(kControlScrollBarLiveProc);
	if (!sControlActionProc)
		sControlActionProc = NewControlActionProc(nsScrollbar::ScrollActionProc);
	// Unfortunately, not disposed when the app quits, but that's still a non-issue.
}

/**-------------------------------------------------------------------------------
 * The create method for a scrollbar, using a nsIWidget as the parent
 * @update  dc 08/31/98
 * @param  aParent -- the widget which will be this widgets parent in the tree
 * @param  aRect -- The bounds in parental coordinates of this widget
 * @param  aHandleEventFunction -- Procedures to be executed for this widget
 * @param  aContext -- device context to be used by this widget
 * @param  aAppShell -- 
 * @param  aToolkit -- toolkit to be used by this widget
 * @param  aInitData -- Initialization data used by frames
 * @return -- NS_OK if everything was created correctly
 */ 
NS_IMETHODIMP nsScrollbar::Create(nsIWidget *aParent,
								const nsRect &aRect,
								EVENT_CALLBACK aHandleEventFunction,
								nsIDeviceContext *aContext,
								nsIAppShell *aAppShell,
								nsIToolkit *aToolkit,
								nsWidgetInitData *aInitData)
{
	Inherited::Create(aParent, aRect, aHandleEventFunction,
						aContext, aAppShell, aToolkit, aInitData);

	return NS_OK;
}

/**-------------------------------------------------------------------------------
 * Destuctor for the nsScrollbar
 * @update	dc 10/31/98
 */ 
nsScrollbar::~nsScrollbar()
{
}

/**-------------------------------------------------------------------------------
 * Implement the standard QueryInterface for NS_IWIDGET_IID and NS_ISUPPORTS_IID
 * @update  dc 08/31/98
 * @param aIID The name of the class implementing the method
 * @param _classiiddef The name of the #define symbol that defines the IID
 * for the class (e.g. NS_ISUPPORTS_IID)
 */ 
nsresult nsScrollbar::QueryInterface(const nsIID& aIID, void** aInstancePtr)
{
	if (nsnull == aInstancePtr) {
			return NS_ERROR_NULL_POINTER;
	}

	static NS_DEFINE_IID(kIScrollbarIID, NS_ISCROLLBAR_IID);
	if (aIID.Equals(kIScrollbarIID)) {
			*aInstancePtr = (void*) ((nsIScrollbar*)this);
			AddRef();
			return NS_OK;
	}

	return nsWindow::QueryInterface(aIID,aInstancePtr);
}

/**-------------------------------------------------------------------------------
 * ScrollActionProc Callback for TrackControl
 * @update	jrm 99/01/11
 * @param ctrl - The Control being tracked
 * @param part - Part of the control (arrow, thumb, gutter) being hit
 */
void nsScrollbar::ScrollActionProc(ControlHandle ctrl, ControlPartCode part)
{
	nsScrollbar* me = (nsScrollbar*)(::GetControlReference(ctrl));
	NS_ASSERTION(nsnull != me, "NULL nsScrollbar");
	if (nsnull != me)
		me->DoScrollAction(part);
}

/**-------------------------------------------------------------------------------
 * ScrollActionProc Callback for TrackControl
 * @update	jrm 99/01/11
 * @param part - Part of the control (arrow, thumb, gutter) being hit
 */
void nsScrollbar::DoScrollAction(ControlPartCode part)
{
	PRUint32 pos;
	PRUint32 incr;
	PRUint32 visibleImageSize;
	PRInt32 scrollBarMessage = 0;
	GetPosition(pos);
	GetLineIncrement(incr);
	GetThumbSize(visibleImageSize);
	switch(part)
	{
		case kControlUpButtonPart:
		{
			scrollBarMessage = NS_SCROLLBAR_LINE_PREV;
			SetPosition(pos - incr);
			break;
		}
		case kControlDownButtonPart:
			scrollBarMessage = NS_SCROLLBAR_LINE_NEXT;
			SetPosition(pos + incr);
			break;
		case kControlPageUpPart:
			scrollBarMessage = NS_SCROLLBAR_PAGE_PREV;
			SetPosition(pos - visibleImageSize);
			break;
		case kControlPageDownPart:
			scrollBarMessage = NS_SCROLLBAR_PAGE_NEXT;
			SetPosition(pos + visibleImageSize);
			break;
		case kControlIndicatorPart:
			scrollBarMessage = NS_SCROLLBAR_POS;
			SetPosition(::GetControl32BitValue(GetControl()));
			break;
	}
	EndDraw();
	
	// send event to scroll the parent
	nsScrollbarEvent scrollBarEvent;
	scrollBarEvent.eventStructType = NS_GUI_EVENT;
	scrollBarEvent.widget = this;
	scrollBarEvent.message = scrollBarMessage;
	GetPosition(pos);
	scrollBarEvent.position = pos;
	Inherited::DispatchWindowEvent(scrollBarEvent);

	// update the area of the parent uncovered by the scrolling
	nsIWidget* parent = GetParent();
	parent->Update();
	NS_RELEASE(parent);

	// update this scrollbar
	this-Invalidate(PR_FALSE);
	this->Update();

	StartDraw();
}

/**-------------------------------------------------------------------------------
 * DispatchMouseEvent handle an event for this scrollbar
 * @update  dc 08/31/98
 * @Param aEvent -- The mouse event to respond to for this button
 * @return -- True if the event was handled, PR_FALSE if we did not handle it.
 */ 
PRBool nsScrollbar::DispatchMouseEvent(nsMouseEvent &aEvent)
{
	PRBool eatEvent = PR_FALSE;
	switch (aEvent.message)
	{
		case NS_MOUSE_LEFT_DOUBLECLICK:
		case NS_MOUSE_LEFT_BUTTON_DOWN:
			NS_ASSERTION(this != 0, "NULL nsScrollbar2");
			::SetControlReference(mControl, (UInt32) this);
			StartDraw();
			{
				Point thePoint;
				thePoint.h = aEvent.point.x;
				thePoint.v = aEvent.point.y;
				mClickedPartCode = ::TestControl(mControl, thePoint);
				if (mClickedPartCode > 0)
					::HiliteControl(mControl, mClickedPartCode);

				switch (mClickedPartCode)
				{
					case kControlUpButtonPart:
					case kControlDownButtonPart:
					case kControlPageUpPart:
					case kControlPageDownPart:
					case kControlIndicatorPart:
						// We are assuming Appearance 1.1 or later, so we
						// have the "live scroll" variant of the scrollbar,
						// which lets you pass the action proc to TrackControl
						// for the thumb (this was illegal in previous
						// versions of the defproc).
						::TrackControl(mControl, thePoint, sControlActionProc);
						// We don't dispatch the mouseDown event because mouseUp is eaten
						// by TrackControl anyway and the only messages the app really
						// cares about are the NS_SCROLLBAR_xxx messages.
						eatEvent = PR_TRUE;
						break;
#if 0
					case kControlIndicatorPart:
						// This is what you have to do for appearance 1.0 or
						// no appearance.
						::TrackControl(mControl, thePoint, nsnull);
						mValue = ::GetControl32BitValue(mControl);
						EndDraw();
						nsScrollbarEvent scrollBarEvent;
						scrollBarEvent.eventStructType = NS_GUI_EVENT;
						scrollBarEvent.widget = this;
						scrollBarEvent.message = NS_SCROLLBAR_POS;
						scrollBarEvent.position = mValue;
						DispatchWindowEvent(scrollBarEvent);
						nsIWidget* parent = GetParent();
						parent->Update();
						NS_RELEASE(parent);
						StartDraw();
						break;
#endif
				}
				SetPosition(mValue);
			}
			EndDraw();
			break;


		case NS_MOUSE_LEFT_BUTTON_UP:
			mClickedPartCode = 0;
			break;

		case NS_MOUSE_EXIT:
			if (mWidgetArmed)
			{
				StartDraw();
				::HiliteControl(mControl, 0);
				EndDraw();
			}
			break;

		case NS_MOUSE_ENTER:
			if (mWidgetArmed)
			{
				StartDraw();
				::HiliteControl(mControl, mClickedPartCode);
				EndDraw();
			}
			break;
	}

	if (eatEvent)
		return PR_TRUE;
	return (Inherited::DispatchMouseEvent(aEvent));

}

/**-------------------------------------------------------------------------------
 *	set the maximum range of a scroll bar
 *	@update	dc 09/16/98
 *	@param	aMaxRange -- the maximum to set this to
 *	@return -- If a good size was returned
 */
NS_METHOD nsScrollbar::SetMaxRange(PRUint32 aEndRange) // really means set full image size.
{
	mFullImageSize = ((int)aEndRange) > 0 ? aEndRange : 10;
	if (mControl)
	{
		StartDraw();
		::SetControl32BitMaximum(
			mControl,
			mFullImageSize > mVisibleImageSize ? mFullImageSize - mVisibleImageSize : 0);
		EndDraw();
	}
	return NS_OK;
}

/**-------------------------------------------------------------------------------
 *	get the maximum range of a scroll bar
 *	@update	dc 09/16/98
 *	@param	aMaxRange -- The current maximum this slider can be
 *	@return -- If a good size was returned
 */
NS_METHOD nsScrollbar::GetMaxRange(PRUint32& aMaxRange) // really means get full image size
{
	aMaxRange = mFullImageSize;
	return NS_OK;
}

/**-------------------------------------------------------------------------------
 *	Set the current position of the slider
 *	@update	dc 09/16/98
 *	@param	aMaxRange -- The current value to set the slider position to.
 *	@return -- NS_OK if the position is valid
 */
NS_METHOD nsScrollbar::SetPosition(PRUint32 aPos)
{
	if ((PRInt32)aPos < 0)
		aPos = 0;
	PRUint32 aMax = mFullImageSize - mVisibleImageSize;
	mValue = ((PRInt32)aPos) > aMax ? aMax : ((int)aPos);
	return NS_OK;
}


/**-------------------------------------------------------------------------------
 *	Get the current position of the slider
 *	@update	dc 09/16/98
 *	@param	aMaxRange -- The current slider position.
 *	@return -- NS_OK if the position is valid
 */
NS_METHOD nsScrollbar::GetPosition(PRUint32& aPos)
{
	aPos = mValue;
	return NS_OK;
}

/**-------------------------------------------------------------------------------
 *	Set the height of a vertical, or width of a horizontal scroll bar thumb control
 *	@update	dc 09/16/98
 *	@param	aSize -- the size to set the thumb control to
 *	@return -- NS_OK if the position is valid
 */
NS_METHOD nsScrollbar::SetThumbSize(PRUint32 aSize)
{
	mVisibleImageSize = ((int)aSize) > 0 ? aSize : 1;

	if (mVisibleImageSize > mFullImageSize)
		mVisibleImageSize = mFullImageSize;
	if (mControl)
	{
		StartDraw();
		SetControlViewSize(mControl, mVisibleImageSize);
		EndDraw();
	}
	return NS_OK;
}

/**-------------------------------------------------------------------------------
 *	get the height of a vertical, or width of a horizontal scroll bar thumb control
 *	@update	dc 09/16/98
 *	@param	aSize -- the size to set the thumb control to
 *	@return -- NS_OK if the position is valid
 */
NS_METHOD nsScrollbar::GetThumbSize(PRUint32& aSize)
{
	aSize = mVisibleImageSize;
	return NS_OK;
}

/**-------------------------------------------------------------------------------
 *	Set the increment of the scroll bar
 *	@update	dc 09/16/98
 *	@param	aLineIncrement -- the control increment
 *	@return -- NS_OK if the position is valid
 */
NS_METHOD nsScrollbar::SetLineIncrement(PRUint32 aLineIncrement)
{
	mLineIncrement	= (((int)aLineIncrement) > 0 ? aLineIncrement : 1);
	return NS_OK;
}


/**-------------------------------------------------------------------------------
 *	Get the increment of the scroll bar
 *	@update	dc 09/16/98
 *	@param aLineIncrement -- the control increment
 *	@return NS_OK if the position is valid
 */
NS_METHOD nsScrollbar::GetLineIncrement(PRUint32& aLineIncrement)
{
	aLineIncrement = mLineIncrement;
	return NS_OK;
}

/**-------------------------------------------------------------------------------
 *	See documentation in nsScrollbar.h
 *	@update	dc 012/10/98
 */
NS_METHOD nsScrollbar::SetParameters(PRUint32 aMaxRange, PRUint32 aThumbSize,
								PRUint32 aPosition, PRUint32 aLineIncrement)
{
	SetLineIncrement(aLineIncrement);
	SetPosition(aPosition);
	mVisibleImageSize = aThumbSize; // needed by SetMaxRange
	SetMaxRange(aMaxRange);
	SetThumbSize(aThumbSize); // Needs to know the maximum value when calling Mac toolbox.

	return NS_OK;
}

#pragma mark -

//-------------------------------------------------------------------------
//
// Get the rect which the Mac control uses. This may be different for
// different controls, so this method allows overriding
//
//-------------------------------------------------------------------------
void nsScrollbar::GetRectForMacControl(nsRect &outRect)
{
		outRect = mBounds;
		outRect.x = outRect.y = 0;
		
		if (mBounds.height > mBounds.width)
		{
			// vertical scroll bar
			outRect.Inflate(0, 1);
		}
		else
		{
			// horizontal scroll bar
			outRect.Inflate(1, 0);
		}
}