/**
 * @file llscrollingpanellist.cpp
 * @brief
 *
 * $LicenseInfo:firstyear=2006&license=viewergpl$
 *
 * Copyright (c) 2006-2009, Linden Research, Inc.
 *
 * Second Life Viewer Source Code
 * The source code in this file ("Source Code") is provided by Linden Lab
 * to you under the terms of the GNU General Public License, version 2.0
 * ("GPL"), unless you have obtained a separate licensing agreement
 * ("Other License"), formally executed by you and Linden Lab.  Terms of
 * the GPL can be found in doc/GPL-license.txt in this distribution, or
 * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
 *
 * There are special exceptions to the terms and conditions of the GPL as
 * it is applied to this Source Code. View the full text of the exception
 * in the file doc/FLOSS-exception.txt in this software distribution, or
 * online at
 * http://secondlifegrid.net/programs/open_source/licensing/flossexception
 *
 * By copying, modifying or distributing this software, you acknowledge
 * that you have read and understood your obligations described above,
 * and agree to abide by those obligations.
 *
 * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
 * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
 * COMPLETENESS OR PERFORMANCE.
 * $/LicenseInfo$
 */

#include "linden_common.h"
#include "llstl.h"

#include "llscrollingpanellist.h"

static const std::string LL_SCROLLING_PANEL_LIST_TAG = "scrolling_panel_list";
static LLRegisterWidget<LLScrollingPanelList> r19(LL_SCROLLING_PANEL_LIST_TAG);

/////////////////////////////////////////////////////////////////////
// LLScrollingPanelList

// This could probably be integrated with LLScrollContainer -SJB

void LLScrollingPanelList::clearPanels()
{
	deleteAllChildren();
	mPanelList.clear();
	reshape(1, 1, false);
}

void LLScrollingPanelList::addPanel(LLScrollingPanel* panel)
{
	addChildAtEnd(panel);
	mPanelList.push_front(panel);

	constexpr S32 GAP_BETWEEN_PANELS = 6;

	// Resize this view
	S32 total_height = 0;
	S32 max_width = 0;
	S32 cur_gap = 0;
	for (std::deque<LLScrollingPanel*>::iterator iter = mPanelList.begin(),
												 end = mPanelList.end();
		 iter != end; ++iter)
	{
		LLScrollingPanel* childp = *iter;
		total_height += childp->getRect().getHeight() + cur_gap;
		max_width = llmax(max_width, childp->getRect().getWidth());
		cur_gap = GAP_BETWEEN_PANELS;
	}
	reshape(max_width, total_height, false);

	// Reposition each of the child views
	S32 cur_y = total_height;
	for (std::deque<LLScrollingPanel*>::iterator iter = mPanelList.begin(),
												 end = mPanelList.end();
		 iter != end; ++iter)
	{
		LLScrollingPanel* childp = *iter;
		cur_y -= childp->getRect().getHeight();
		childp->translate(-childp->getRect().mLeft,
						  cur_y - childp->getRect().mBottom);
		cur_y -= GAP_BETWEEN_PANELS;
	}
}

void LLScrollingPanelList::updatePanels(bool allow_modify)
{
	for (std::deque<LLScrollingPanel*>::iterator iter = mPanelList.begin(),
												 end = mPanelList.end();
		 iter != end; ++iter)
    {
		LLScrollingPanel* childp = *iter;
		childp->updatePanel(allow_modify);
    }
}

void LLScrollingPanelList::updatePanelVisiblilty()
{
	// Determine visibility of children.
	S32 BORDER_WIDTH = 2;  // HACK

	LLRect parent_local_rect = getParent()->getRect();
	parent_local_rect.stretch(-BORDER_WIDTH);

	LLRect parent_screen_rect;
	getParent()->localPointToScreen(BORDER_WIDTH, 0, &parent_screen_rect.mLeft,
									&parent_screen_rect.mBottom);
	getParent()->localPointToScreen(parent_local_rect.getWidth() - BORDER_WIDTH,
									parent_local_rect.getHeight() - BORDER_WIDTH,
									&parent_screen_rect.mRight,
									&parent_screen_rect.mTop);

	for (std::deque<LLScrollingPanel*>::iterator iter = mPanelList.begin(),
												 end = mPanelList.end();
		 iter != end; ++iter)
	{
		LLScrollingPanel* childp = *iter;
		const LLRect& local_rect = childp->getRect();
		LLRect screen_rect;
		childp->localPointToScreen(0, 0, &screen_rect.mLeft,
								   &screen_rect.mBottom);
		childp->localPointToScreen(local_rect.getWidth(),
								   local_rect.getHeight(),
								   &screen_rect.mRight, &screen_rect.mTop);

		bool intersects = screen_rect.mRight > parent_screen_rect.mLeft &&
						  screen_rect.mLeft < parent_screen_rect.mRight &&
						  screen_rect.mTop > parent_screen_rect.mBottom &&
						  screen_rect.mBottom < parent_screen_rect.mTop;

		childp->setVisible(intersects);
	}
}

void LLScrollingPanelList::draw()
{
	updatePanelVisiblilty();
	LLUICtrl::draw();
}

//virtual
const std::string& LLScrollingPanelList::getTag() const
{
	return LL_SCROLLING_PANEL_LIST_TAG;
}

//virtual
LLXMLNodePtr LLScrollingPanelList::getXML(bool save_children) const
{
	LLXMLNodePtr node = LLUICtrl::getXML();
	node->setName(LL_SCROLLING_PANEL_LIST_TAG);
	return node;
}

//static
LLView* LLScrollingPanelList::fromXML(LLXMLNodePtr node, LLView* parent,
									  LLUICtrlFactory* factory)
{
    std::string name = LL_SCROLLING_PANEL_LIST_TAG;
    node->getAttributeString("name", name);

    LLRect rect;
    createRect(node, rect, parent, LLRect());

    LLScrollingPanelList* scrolling_panel_list = new LLScrollingPanelList(name,
																		  rect);
    scrolling_panel_list->initFromXML(node, parent);
    return scrolling_panel_list;
}