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 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this

  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

 //

 // Eric Vaughan

 // Netscape Communications

 //

 // See documentation in associated header file

 //

 #include "nsScrollbarButtonFrame.h"

 #include "nsPresContext.h"

 #include "nsIContent.h"

 #include "nsCOMPtr.h"

 #include "nsNameSpaceManager.h"

 #include "nsGkAtoms.h"

 #include "nsSliderFrame.h"

 #include "nsScrollbarFrame.h"

 #include "nsIScrollbarMediator.h"

 #include "nsRepeatService.h"

 #include "mozilla/LookAndFeel.h"

 #include "mozilla/MouseEvents.h"

 using namespace mozilla;

 //

 // NS_NewToolbarFrame

 //

 // Creates a new Toolbar frame and returns it

 //

 nsIFrame*

 NS_NewScrollbarButtonFrame (nsIPresShell* aPresShell, nsStyleContext* aContext)

 {

   return new (aPresShell) nsScrollbarButtonFrame(aPresShell, aContext);

 }

 NS_IMPL_FRAMEARENA_HELPERS(nsScrollbarButtonFrame)

 nsresult

 nsScrollbarButtonFrame::HandleEvent(nsPresContext* aPresContext,

                                     WidgetGUIEvent* aEvent,

                                     nsEventStatus* aEventStatus)

 {  

   NS_ENSURE_ARG_POINTER(aEventStatus);

   // If a web page calls event.preventDefault() we still want to

   // scroll when scroll arrow is clicked. See bug 511075.

   if (!mContent->IsInNativeAnonymousSubtree() &&

       nsEventStatus_eConsumeNoDefault == *aEventStatus) {

     return NS_OK;

   }

   switch (aEvent->message) {

     case NS_MOUSE_BUTTON_DOWN:

       mCursorOnThis = true;

       // if we didn't handle the press ourselves, pass it on to the superclass

       if (HandleButtonPress(aPresContext, aEvent, aEventStatus)) {

         return NS_OK;

       }

       break;

     case NS_MOUSE_BUTTON_UP:

       HandleRelease(aPresContext, aEvent, aEventStatus);

       break;

     case NS_MOUSE_EXIT_SYNTH:

       mCursorOnThis = false;

       break;

     case NS_MOUSE_MOVE: {

       nsPoint cursor =

         nsLayoutUtils::GetEventCoordinatesRelativeTo(aEvent, this);

       nsRect frameRect(nsPoint(0, 0), GetSize());

       mCursorOnThis = frameRect.Contains(cursor);

       break;

     }

   }

   return nsButtonBoxFrame::HandleEvent(aPresContext, aEvent, aEventStatus);

 }

 bool

 nsScrollbarButtonFrame::HandleButtonPress(nsPresContext* aPresContext,

                                           WidgetGUIEvent* aEvent,

                                           nsEventStatus* aEventStatus)

 {

   // Get the desired action for the scrollbar button.

   LookAndFeel::IntID tmpAction;

   uint16_t button = aEvent->AsMouseEvent()->button;

   if (button == WidgetMouseEvent::eLeftButton) {

     tmpAction = LookAndFeel::eIntID_ScrollButtonLeftMouseButtonAction;

   } else if (button == WidgetMouseEvent::eMiddleButton) {

     tmpAction = LookAndFeel::eIntID_ScrollButtonMiddleMouseButtonAction;

   } else if (button == WidgetMouseEvent::eRightButton) {

     tmpAction = LookAndFeel::eIntID_ScrollButtonRightMouseButtonAction;

   } else {

     return false;

   }

   // Get the button action metric from the pres. shell.

   int32_t pressedButtonAction;

   if (NS_FAILED(LookAndFeel::GetInt(tmpAction, &pressedButtonAction))) {

     return false;

   }

   // get the scrollbar control

   nsIFrame* scrollbar;

   GetParentWithTag(nsGkAtoms::scrollbar, this, scrollbar);

   if (scrollbar == nullptr)

     return false;

   // get the scrollbars content node

   nsIContent* content = scrollbar->GetContent();

   static nsIContent::AttrValuesArray strings[] = { &nsGkAtoms::increment,

                                                    &nsGkAtoms::decrement,

                                                    nullptr };

   int32_t index = mContent->FindAttrValueIn(kNameSpaceID_None,

                                             nsGkAtoms::type,

                                             strings, eCaseMatters);

   int32_t direction;

   if (index == 0) 

     direction = 1;

   else if (index == 1)

     direction = -1;

   else

     return false;

   // Whether or not to repeat the click action.

   bool repeat = true;

   // Use smooth scrolling by default.

   bool smoothScroll = true;

   switch (pressedButtonAction) {

     case 0:

       mIncrement = direction * nsSliderFrame::GetIncrement(content);

       break;

     case 1:

       mIncrement = direction * nsSliderFrame::GetPageIncrement(content);

       break;

     case 2:

       if (direction == -1)

         mIncrement = -nsSliderFrame::GetCurrentPosition(content);

       else

         mIncrement = nsSliderFrame::GetMaxPosition(content) - 

                      nsSliderFrame::GetCurrentPosition(content);

       // Don't repeat or use smooth scrolling if scrolling to beginning or end

       // of a page.

       repeat = smoothScroll = false;

       break;

     case 3:

     default:

       // We were told to ignore this click, or someone assigned a non-standard

       // value to the button's action.

       return false;

   }

   // set this attribute so we can style it later

   nsWeakFrame weakFrame(this);

   mContent->SetAttr(kNameSpaceID_None, nsGkAtoms::active, NS_LITERAL_STRING("true"), true);

   nsIPresShell::SetCapturingContent(mContent, CAPTURE_IGNOREALLOWED);

   if (weakFrame.IsAlive()) {

     DoButtonAction(smoothScroll);

   }

   if (repeat)

     StartRepeat();

   return true;

 }

 NS_IMETHODIMP 

 nsScrollbarButtonFrame::HandleRelease(nsPresContext* aPresContext,

                                       WidgetGUIEvent* aEvent,

                                       nsEventStatus* aEventStatus)

 {

   nsIPresShell::SetCapturingContent(nullptr, 0);

   // we're not active anymore

   mContent->UnsetAttr(kNameSpaceID_None, nsGkAtoms::active, true);

   StopRepeat();

   return NS_OK;

 }

 void nsScrollbarButtonFrame::Notify()

 {

   // Since this is only going to get called if we're scrolling a page length

   // or a line increment, we will always use smooth scrolling.

   if (mCursorOnThis ||

       LookAndFeel::GetInt(

         LookAndFeel::eIntID_ScrollbarButtonAutoRepeatBehavior, 0)) {

     DoButtonAction(true);

   }

 }

 void

 nsScrollbarButtonFrame::MouseClicked(nsPresContext* aPresContext,

                                      WidgetGUIEvent* aEvent) 

 {

   nsButtonBoxFrame::MouseClicked(aPresContext, aEvent);

   //MouseClicked();

 }

 void

 nsScrollbarButtonFrame::DoButtonAction(bool aSmoothScroll) 

 {

   // get the scrollbar control

   nsIFrame* scrollbar;

   GetParentWithTag(nsGkAtoms::scrollbar, this, scrollbar);

   if (scrollbar == nullptr)

     return;

   // get the scrollbars content node

   nsCOMPtr<nsIContent> content = scrollbar->GetContent();

   // get the current pos

   int32_t curpos = nsSliderFrame::GetCurrentPosition(content);

   int32_t oldpos = curpos;

   // get the max pos

   int32_t maxpos = nsSliderFrame::GetMaxPosition(content);

   // increment the given amount

   if (mIncrement)

     curpos += mIncrement;

   // make sure the current position is between the current and max positions

   if (curpos < 0)

     curpos = 0;

   else if (curpos > maxpos)

     curpos = maxpos;

   nsScrollbarFrame* sb = do_QueryFrame(scrollbar);

   if (sb) {

     nsIScrollbarMediator* m = sb->GetScrollbarMediator();

     if (m) {

       m->ScrollbarButtonPressed(sb, oldpos, curpos);

       return;

     }

   }

   // set the current position of the slider.

   nsAutoString curposStr;

   curposStr.AppendInt(curpos);

   if (aSmoothScroll)

     content->SetAttr(kNameSpaceID_None, nsGkAtoms::smooth, NS_LITERAL_STRING("true"), false);

   content->SetAttr(kNameSpaceID_None, nsGkAtoms::curpos, curposStr, true);

   if (aSmoothScroll)

     content->UnsetAttr(kNameSpaceID_None, nsGkAtoms::smooth, false);

 }

 nsresult

 nsScrollbarButtonFrame::GetChildWithTag(nsPresContext* aPresContext,

                                         nsIAtom* atom, nsIFrame* start,

                                         nsIFrame*& result)

 {

   // recursively search our children

   nsIFrame* childFrame = start->GetFirstPrincipalChild();

   while (nullptr != childFrame) 

   {    

     // get the content node

     nsIContent* child = childFrame->GetContent();

     if (child) {

       // see if it is the child

        if (child->Tag() == atom)

        {

          result = childFrame;

          return NS_OK;

        }

     }

      // recursive search the child

      GetChildWithTag(aPresContext, atom, childFrame, result);

      if (result != nullptr) 

        return NS_OK;

     childFrame = childFrame->GetNextSibling();

   }

   result = nullptr;

   return NS_OK;

 }

 nsresult

 nsScrollbarButtonFrame::GetParentWithTag(nsIAtom* toFind, nsIFrame* start,

                                          nsIFrame*& result)

 {

    while (start)

    {

       start = start->GetParent();

       if (start) {

         // get the content node

         nsIContent* child = start->GetContent();

         if (child && child->Tag() == toFind) {

           result = start;

           return NS_OK;

         }

       }

    }

    result = nullptr;

    return NS_OK;

 }

 void

 nsScrollbarButtonFrame::DestroyFrom(nsIFrame* aDestructRoot)

 {

   // Ensure our repeat service isn't going... it's possible that a scrollbar can disappear out

   // from under you while you're in the process of scrolling.

   StopRepeat();

   nsButtonBoxFrame::DestroyFrom(aDestructRoot);

 }