/*****************************************************************************
 * ctrl_tree.cpp
 *****************************************************************************
 * Copyright (C) 2003 VideoLAN
 * $Id$
 *
 * Authors: Antoine Cellerier <dionoea@videolan.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
 *****************************************************************************/

#include <math.h>
#include "ctrl_tree.hpp"
#include "../src/os_factory.hpp"
#include "../src/os_graphics.hpp"
#include "../src/generic_bitmap.hpp"
#include "../src/generic_font.hpp"
#include "../src/scaled_bitmap.hpp"
#include "../utils/position.hpp"
#include "../utils/ustring.hpp"
#include "../events/evt_key.hpp"
#include "../events/evt_mouse.hpp"
#include "../events/evt_scroll.hpp"
#include "vlc_keys.h"
#ifdef sun
#   include "solaris_specific.h" // for lrint
#endif

#define SCROLL_STEP 0.05
#define LINE_INTERVAL 1  // Number of pixels inserted between 2 lines


CtrlTree::CtrlTree( intf_thread_t *pIntf,
                    VarTree &rTree,
                    const GenericFont &rFont,
                    const GenericBitmap *pBgBitmap,
                    const GenericBitmap *pItemBitmap,
                    const GenericBitmap *pOpenBitmap,
                    const GenericBitmap *pClosedBitmap,
                    uint32_t fgColor,
                    uint32_t playColor,
                    uint32_t bgColor1,
                    uint32_t bgColor2,
                    uint32_t selColor,
                    const UString &rHelp,
                    VarBool *pVisible ):
    CtrlGeneric( pIntf,rHelp, pVisible), m_rTree( rTree), m_rFont( rFont ),
    m_pBgBitmap( pBgBitmap ), m_pItemBitmap( pItemBitmap ),
    m_pOpenBitmap( pOpenBitmap ), m_pClosedBitmap( pClosedBitmap ),
    m_fgColor( fgColor ), m_playColor( playColor ), m_bgColor1( bgColor1 ),
    m_bgColor2( bgColor2 ), m_selColor( selColor ),
    m_pLastSelected( NULL ), m_pImage( NULL ), m_dontMove( false )
{
    // Observe the tree and position variables
    m_rTree.addObserver( this );
    m_rTree.getPositionVar().addObserver( this );

    m_firstPos = m_rTree.begin();

    makeImage();
}

CtrlTree::~CtrlTree()
{
    m_rTree.getPositionVar().delObserver( this );
    m_rTree.delObserver( this );
    if( m_pImage )
    {
        delete m_pImage;
    }
}

int CtrlTree::itemHeight()
{
    int itemHeight = m_rFont.getSize();
    if( m_pClosedBitmap )
    {
        itemHeight = __MAX( m_pClosedBitmap->getHeight(), itemHeight );
    }
    if( m_pOpenBitmap )
    {
        itemHeight = __MAX( m_pOpenBitmap->getHeight(), itemHeight );
    }
    if( m_pItemBitmap )
    {
        itemHeight = __MAX( m_pItemBitmap->getHeight(), itemHeight );
    }
    itemHeight += LINE_INTERVAL;
    return itemHeight;
}

int CtrlTree::itemImageWidth()
{
    int bitmapWidth = 5;
    if( m_pClosedBitmap )
    {
        bitmapWidth = __MAX( m_pClosedBitmap->getWidth(), bitmapWidth );
    }
    if( m_pOpenBitmap )
    {
        bitmapWidth = __MAX( m_pOpenBitmap->getWidth(), bitmapWidth );
    }
    if( m_pItemBitmap )
    {
        bitmapWidth = __MAX( m_pItemBitmap->getWidth(), bitmapWidth );
    }
    return bitmapWidth + 2;
}

int CtrlTree::maxItems()
{
    const Position *pPos = getPosition();
    if( !pPos )
    {
        return -1;
    }
    return pPos->getHeight() / itemHeight();
}


void CtrlTree::onUpdate( Subject<VarTree, tree_update*> &rTree,
                         tree_update *arg )
{
    if( arg->i_type == 0 ) // Item update
    {
        if( arg->b_active_item )
        {
            autoScroll();
            ///\todo We should make image if we are visible in the view
            makeImage();
        }
    }
    /// \todo handle delete in a more clever way
    else if ( arg->i_type == 1 ) // Global change or deletion
    {
        m_firstPos = m_rTree.begin();
        makeImage();
    }
    else if ( arg->i_type == 2 ) // Item-append
    {
        /// \todo Check if the item is really visible in the view
        // (we only check if it in the document)
        if( arg->b_visible == true )
        {
            makeImage();
        }
    }
    else if( arg->i_type == 3 ) // item-del
    {
        /* Make sure firstPos and lastSelected are still valid */
        while( m_firstPos->m_deleted && m_firstPos != m_rTree.root()->begin() )
        {
            m_firstPos = m_rTree.getPrevVisibleItem( m_firstPos );
        }
        if( m_firstPos->m_deleted ) m_firstPos = m_rTree.root()->begin();

        if( arg->b_visible == true )
        {
            makeImage();
        }
    }
    notifyLayout();
}

void CtrlTree::onUpdate( Subject<VarPercent, void*> &rPercent, void* arg)
{
    // Determine what is the first item to display
    VarTree::Iterator it = m_rTree.begin();

    if( m_dontMove ) return;

    int excessItems = m_rTree.visibleItems() - maxItems();

    if( excessItems > 0)
    {
        VarPercent &rVarPos = m_rTree.getPositionVar();
        // a simple (int)(...) causes rounding errors !
#ifdef _MSC_VER
#   define lrint (int)
#endif
        it = m_rTree.getVisibleItem(lrint( (1.0 - rVarPos.get()) * (double)excessItems ) + 1);
    }
    if( m_firstPos != it )
    {
        // Redraw the control if the position has changed
        m_firstPos = it;
        makeImage();
        notifyLayout();
    }
}

void CtrlTree::onResize()
{
    // Determine what is the first item to display
    VarTree::Iterator it = m_rTree.begin();

    int excessItems = m_rTree.visibleItems() - maxItems();

    if( excessItems > 0)
    {
        VarPercent &rVarPos = m_rTree.getPositionVar();
        // a simple (int)(...) causes rounding errors !
#ifdef _MSC_VER
#   define lrint (int)
#endif
        it = m_rTree.getVisibleItem(lrint( (1.0 - rVarPos.get()) * (double)excessItems ) + 1);
    }
    // Redraw the control if the position has changed
    m_firstPos = it;
    makeImage();
    notifyLayout();
}

void CtrlTree::onPositionChange()
{
    makeImage();
    notifyLayout();
}

void CtrlTree::handleEvent( EvtGeneric &rEvent )
{
    bool bChangedPosition = false;
    VarTree::Iterator toShow; bool needShow = false;
    if( rEvent.getAsString().find( "key:down" ) != string::npos )
    {
        int key = ((EvtKey&)rEvent).getKey();
        VarTree::Iterator it;
        bool previousWasSelected = false;

        /* Delete the selection */
        if( key == KEY_DELETE )
        {
            m_rTree.delSelected();
        }
        else if( key == KEY_PAGEDOWN )
        {
            it = m_firstPos;
            int i = (int)(maxItems()*1.5);
            while( i >= 0 )
            {
                VarTree::Iterator it_old = it;
                it = m_rTree.getNextVisibleItem( it );
                /* End is already visible, dont' scroll */
                if( it == m_rTree.end() )
                {
                    it = it_old;
                    break;
                }
                needShow = true;
                i--;
            }
            if( needShow )
            {
                ensureVisible( it );
                makeImage();
                notifyLayout();
                return;
            }
        }
        else if (key == KEY_PAGEUP )
        {
            it = m_firstPos;
            int i = maxItems();
            while( i >= maxItems()/2 )
            {
                it = m_rTree.getPrevVisibleItem( it );
                /* End is already visible, dont' scroll */
                if( it == m_rTree.begin() )
                {
                    break;
                }
                i--;
            }
            ensureVisible( it );
            makeImage();
            notifyLayout();
            return;
        }


        for( it = m_rTree.begin(); it != m_rTree.end();
             it = m_rTree.getNextVisibleItem( it ) )
        {
            VarTree::Iterator next = m_rTree.getNextVisibleItem( it );
            if( key == KEY_UP )
            {
                // Scroll up one item
                if( ( it->parent()
                      && it != it->parent()->begin() )
                    || &*it != m_pLastSelected )
                {
                    bool nextWasSelected = ( &*next == m_pLastSelected );
                    it->m_selected = nextWasSelected;
                    if( nextWasSelected )
                    {
                        m_pLastSelected = &*it;
                        needShow = true; toShow = it;
                    }
                }
            }
            else if( key == KEY_DOWN )
            {
                // Scroll down one item
                if( ( it->parent()
                      && next != it->parent()->end() )
                    || &*it != m_pLastSelected )
                {
                    (*it).m_selected = previousWasSelected;
                }
                if( previousWasSelected )
                {
                    m_pLastSelected = &*it;
                    needShow = true; toShow = it;
                    previousWasSelected = false;
                }
                else
                {
                    previousWasSelected = ( &*it == m_pLastSelected );
                }
            }
            else if( key == KEY_RIGHT )
            {
                // Go down one level (and expand node)
                if( &*it == m_pLastSelected )
                {
                    if( it->m_expanded )
                    {
                        if( it->size() )
                        {
                            it->m_selected = false;
                            it->begin()->m_selected = true;
                            m_pLastSelected = &*(it->begin());
                        }
                        else
                        {
                            m_rTree.action( &*it );
                        }
                    }
                    else
                    {
                        it->m_expanded = true;
                        bChangedPosition = true;
                    }
                }
            }
            else if( key == KEY_LEFT )
            {
                // Go up one level (and close node)
                if( &*it == m_pLastSelected )
                {
                    if( it->m_expanded && it->size() )
                    {
                        it->m_expanded = false;
                        bChangedPosition = true;
                    }
                    else
                    {
                        if( it->parent() && it->parent() != &m_rTree)
                        {
                            it->m_selected = false;
                            m_pLastSelected = it->parent();
                            m_pLastSelected->m_selected = true;
                        }
                    }
                }
            }
            else if( key == KEY_ENTER || key == KEY_SPACE )
            {
                // Go up one level (and close node)
                if( &*it == m_pLastSelected )
                {
                    m_rTree.action( &*it );
                }
            }
        }
        if( needShow )
            ensureVisible( toShow );

        // Redraw the control
        makeImage();
        notifyLayout();
    }

    else if( rEvent.getAsString().find( "mouse:left" ) != string::npos )
    {
        EvtMouse &rEvtMouse = (EvtMouse&)rEvent;
        const Position *pos = getPosition();
        int yPos = ( rEvtMouse.getYPos() - pos->getTop() ) / itemHeight();
        int xPos = rEvtMouse.getXPos() - pos->getLeft();
        VarTree::Iterator it;

        if( rEvent.getAsString().find( "mouse:left:down:ctrl,shift" ) !=
            string::npos )
        {
            VarTree::Iterator itClicked = findItemAtPos( yPos );
            // Flag to know if the current item must be selected
            bool select = false;
            for( it = m_rTree.begin(); it != m_rTree.end();
                 it = m_rTree.getNextVisibleItem( it ) )
            {
                bool nextSelect = select;
                if( it == itClicked || &*it == m_pLastSelected )
                {
                    if( select )
                    {
                        nextSelect = false;
                    }
                    else
                    {
                        select = true;
                        nextSelect = true;
                    }
                }
                it->m_selected = (*it).m_selected || select;
                select = nextSelect;
            }
        }
        else if( rEvent.getAsString().find( "mouse:left:down:ctrl" ) !=
                 string::npos )
        {
            // Invert the selection of the item
            it = findItemAtPos( yPos );
            if( it != m_rTree.end() )
            {
                it->m_selected = !it->m_selected;
                m_pLastSelected = &*it;
            }
        }
        else if( rEvent.getAsString().find( "mouse:left:down:shift" ) !=
                 string::npos )
        {
            VarTree::Iterator itClicked = findItemAtPos( yPos );
            // Flag to know if the current item must be selected
            bool select = false;
            for( it = m_rTree.begin(); it != m_rTree.end();
                 it = m_rTree.getNextVisibleItem( it ) )
            {
                bool nextSelect = select;
                if( it == itClicked || &*it == m_pLastSelected )
                {
                    if( select )
                    {
                        nextSelect = false;
                    }
                    else
                    {
                        select = true;
                        nextSelect = true;
                    }
                }
                it->m_selected = select;
                select = nextSelect;
            }
        }
        else if( rEvent.getAsString().find( "mouse:left:down" ) !=
                 string::npos )
        {
            it = findItemAtPos(yPos);
            if( it != m_rTree.end() )
            {
                if( it->size() && xPos > (it->depth() - 1) * itemImageWidth()
                    && xPos < it->depth() * itemImageWidth() )
                {
                    // Fold/unfold the item
                    it->m_expanded = !it->m_expanded;
                    bChangedPosition = true;
                }
                else
                {
                    // Unselect any previously selected item
                    VarTree::Iterator it2;
                    for( it2 = m_rTree.begin(); it2 != m_rTree.end();
                         it2 = m_rTree.getNextVisibleItem( it2 ) )
                    {
                        it2->m_selected = false;
                    }
                    // Select the new item
                    if( it != m_rTree.end() )
                    {
                        it->m_selected = true;
                        m_pLastSelected = &*it;
                    }
                }
            }
        }

        else if( rEvent.getAsString().find( "mouse:left:dblclick" ) !=
                 string::npos )
        {
            it = findItemAtPos(yPos);
            if( it != m_rTree.end() )
            {
               // Execute the action associated to this item
               m_rTree.action( &*it );
            }
        }
        // Redraw the control
        makeImage();
        notifyLayout();
    }

    else if( rEvent.getAsString().find( "scroll" ) != string::npos )
    {
        int direction = ((EvtScroll&)rEvent).getDirection();

        double percentage = m_rTree.getPositionVar().get();
        double step = 2.0 / (double)m_rTree.visibleItems();
        if( direction == EvtScroll::kUp )
        {
            percentage += step;
        }
        else
        {
            percentage -= step;
        }
        m_rTree.getPositionVar().set( percentage );
    }

    /* We changed the nodes, let's fix teh position var */
    if( bChangedPosition )
    {
        VarTree::Iterator it;
        int i = 0;
        int iFirst = 0;
        for( it = m_rTree.begin(); it != m_rTree.end();
             it = m_rTree.getNextVisibleItem( it ) )
        {
            i++;
            if( it == m_firstPos )
            {
                iFirst = i;
                break;
            }
        }
        iFirst += maxItems();
        if( iFirst >= m_rTree.visibleItems() ) iFirst = m_rTree.visibleItems();
        float f_new = (float)iFirst / (float)m_rTree.visibleItems();
        m_dontMove = true;
        m_rTree.getPositionVar().set( 1.0 - f_new );
        m_dontMove = false;
    }
}

bool CtrlTree::mouseOver( int x, int y ) const
{
    const Position *pPos = getPosition();
    return ( pPos
       ? x >= 0 && x <= pPos->getWidth() && y >= 0 && y <= pPos->getHeight()
       : false);
}

void CtrlTree::draw( OSGraphics &rImage, int xDest, int yDest )
{
    if( m_pImage )
    {
        rImage.drawGraphics( *m_pImage, 0, 0, xDest, yDest );
    }
}

bool CtrlTree::ensureVisible( VarTree::Iterator item )
{
    // Find the item to focus
    int focusItemIndex = 0;
    VarTree::Iterator it;

    m_rTree.ensureExpanded( item );

    for( it = m_rTree.begin(); it != m_rTree.end();
         it = m_rTree.getNextVisibleItem( it ) )
    {
        if( it->m_id == item->m_id ) break;
        focusItemIndex++;
    }
   return ensureVisible( focusItemIndex );
}

bool CtrlTree::ensureVisible( int focusItemIndex )
{
    // Find  m_firstPos
    VarTree::Iterator it;
    int firstPosIndex = 0;
    for( it = m_rTree.begin(); it != m_rTree.end();
         it = m_rTree.getNextVisibleItem( it ) )
    {
        if( it == m_firstPos ) break;
        firstPosIndex++;
    }

    if( it == m_rTree.end() ) return false;


    if( it != m_rTree.end()
        && ( focusItemIndex < firstPosIndex
           || focusItemIndex > firstPosIndex + maxItems() ) )
    {
        // Scroll to have the wanted stream visible
        VarPercent &rVarPos = m_rTree.getPositionVar();
        rVarPos.set( 1.0 - (double)focusItemIndex /
                           (double)m_rTree.visibleItems() );
        return true;
    }
    return false;
}

void CtrlTree::autoScroll()
{
    // Find the current playing stream
    int playIndex = 0;
    VarTree::Iterator it;

    for( it = m_rTree.begin(); it != m_rTree.end();
         it = m_rTree.getNextItem( it ) )
    {
        if( it->m_playing )
        {
           m_rTree.ensureExpanded( it );
           break;
        }
    }
    for( it = m_rTree.begin(); it != m_rTree.end();
         it = m_rTree.getNextVisibleItem( it ) )
    {
        if( it->m_playing )
           break;
        playIndex++;
    }

    if( it == m_rTree.end() ) return;


    ensureVisible( playIndex );
}


void CtrlTree::makeImage()
{
    stats_TimerStart( getIntf(), "[Skins] Playlist image",
                      STATS_TIMER_SKINS_PLAYTREE_IMAGE );
    if( m_pImage )
    {
        delete m_pImage;
    }

    // Get the size of the control
    const Position *pPos = getPosition();
    if( !pPos )
    {
        stats_TimerStop( getIntf(), STATS_TIMER_SKINS_PLAYTREE_IMAGE );
        return;
    }
    int width = pPos->getWidth();
    int height = pPos->getHeight();

    int i_itemHeight = itemHeight();

    // Create an image
    OSFactory *pOsFactory = OSFactory::instance( getIntf() );
    m_pImage = pOsFactory->createOSGraphics( width, height );

    VarTree::Iterator it = m_firstPos;

    if( m_pBgBitmap )
    {
        // Draw the background bitmap
        ScaledBitmap bmp( getIntf(), *m_pBgBitmap, width, height );
        m_pImage->drawBitmap( bmp, 0, 0 );

        for( int yPos = 0; yPos < height; yPos += i_itemHeight )
        {
            if( it != m_rTree.end() )
            {
                if( (*it).m_selected )
                {
                    int rectHeight = __MIN( i_itemHeight, height - yPos );
                    m_pImage->fillRect( 0, yPos, width, rectHeight,
                                        m_selColor );
                }
                do
                {
                    it = m_rTree.getNextVisibleItem( it );
                } while( it->m_deleted );
            }
        }
    }
    else
    {
        // FIXME (TRYME)
        // Fill background with background color
        uint32_t bgColor = m_bgColor1;
        m_pImage->fillRect( 0, 0, width, height, bgColor );
        for( int yPos = 0; yPos < height; yPos += i_itemHeight )
        {
            int rectHeight = __MIN( i_itemHeight, height - yPos );
            if( it != m_rTree.end() )
            {
                uint32_t color = ( it->m_selected ? m_selColor : bgColor );
                m_pImage->fillRect( 0, yPos, width, rectHeight, color );
                do
                {
                    it = m_rTree.getNextVisibleItem( it );
                } while( it->m_deleted );
            }
            else
            {
                m_pImage->fillRect( 0, yPos, width, rectHeight, bgColor );
            }
            bgColor = ( bgColor == m_bgColor1 ? m_bgColor2 : m_bgColor1 );
        }
    }

    int bitmapWidth = itemImageWidth();

    int yPos = 0;
    it = m_firstPos;
    while( it != m_rTree.end() && yPos < height )
    {
        const GenericBitmap *m_pCurBitmap;
        UString *pStr = (UString*)(it->m_cString.get());
        uint32_t color = ( it->m_playing ? m_playColor : m_fgColor );

        // Draw the text
        if( pStr != NULL )
        {
            int depth = it->depth();
            GenericBitmap *pText = m_rFont.drawString( *pStr, color, width - bitmapWidth * depth );
            if( !pText )
            {
                stats_TimerStop( getIntf(), STATS_TIMER_SKINS_PLAYTREE_IMAGE );
                return;
            }
            if( it->size() )
                m_pCurBitmap = it->m_expanded ? m_pOpenBitmap : m_pClosedBitmap;
            else
                m_pCurBitmap = m_pItemBitmap;

            if( m_pCurBitmap )
            {
                // Make sure we are centered on the line
                int yPos2 = yPos+(i_itemHeight-m_pCurBitmap->getHeight()+1)/2;
                if( yPos2 >= height )
                {
                    delete pText;
                    break;
                }
                m_pImage->drawBitmap( *m_pCurBitmap, 0, 0,
                                      bitmapWidth * (depth - 1 ), yPos2,
                                      m_pCurBitmap->getWidth(),
                                      __MIN( m_pCurBitmap->getHeight(),
                                             height -  yPos2), true );
            }
            yPos += i_itemHeight - pText->getHeight();
            int ySrc = 0;
            if( yPos < 0 )
            {
                ySrc = - yPos;
                yPos = 0;
            }
            int lineHeight = __MIN( pText->getHeight() - ySrc, height - yPos );
            m_pImage->drawBitmap( *pText, 0, ySrc, bitmapWidth * depth, yPos,
                                  pText->getWidth(),
                                  lineHeight, true );
            yPos += (pText->getHeight() - ySrc );
            delete pText;
        }
        do {
        it = m_rTree.getNextVisibleItem( it );
        } while( it->m_deleted );
    }
    stats_TimerStop( getIntf(), STATS_TIMER_SKINS_PLAYTREE_IMAGE );
}

VarTree::Iterator CtrlTree::findItemAtPos( int pos )
{
    // The first item is m_firstPos.
    // We decrement pos as we try the other items, until pos == 0.
    VarTree::Iterator it;
    for( it = m_firstPos; it != m_rTree.end() && pos != 0;
         it = m_rTree.getNextVisibleItem( it ) )
    {
        pos--;
    }

    return it;
}
