#include "Chunk.h"
#include "Constants.h"
#include "Game.h"
#include "NoBlock.h"


Chunk::Chunk( Framework::Punkt location, int dimensionId )
    : ReferenceCounter(),
    dimensionId( dimensionId ),
    location( location ),
    added( 0 )
{
    blocks = new Block * [ CHUNK_SIZE * CHUNK_SIZE * WORLD_HEIGHT ];
    blockIds = new unsigned short[ CHUNK_SIZE * CHUNK_SIZE * WORLD_HEIGHT ];
    memset( blocks, 0, CHUNK_SIZE * CHUNK_SIZE * WORLD_HEIGHT * sizeof( Block* ) );
    memset( blockIds, 0, CHUNK_SIZE * CHUNK_SIZE * WORLD_HEIGHT * sizeof( unsigned short ) );
    zNeighbours[ 0 ] = 0;
    zNeighbours[ 1 ] = 0;
    zNeighbours[ 2 ] = 0;
    zNeighbours[ 3 ] = 0;
}

Chunk::Chunk( Framework::Punkt location, int dimensionId, Framework::StreamReader* zReader )
    : Chunk( location, dimensionId )
{
    load( zReader );
}

Chunk::~Chunk()
{
    for( int i = 0; i < CHUNK_SIZE * CHUNK_SIZE * WORLD_HEIGHT; i++ )
    {
        if( blocks[ i ] )
            blocks[ i ]->release();
    }
    delete[] blocks;
    delete[] blockIds;
}

Framework::Either<Block*, int> Chunk::zBlockNeighbor( Framework::Vec3<int> location )
{
    if( location.x >= 0 && location.x < CHUNK_SIZE && location.y >= 0 && location.y < CHUNK_SIZE && location.z >= 0 && location.z < WORLD_HEIGHT )
    {
        int index = (location.x * CHUNK_SIZE + location.y) * WORLD_HEIGHT + location.z;
        if( blocks[ index ] )
            return blocks[ index ];
        else
            return (int)blockIds[ index ];
    }
    if( added && location.z >= 0 && location.z < WORLD_HEIGHT )
        return Game::INSTANCE->zBlockAt( { location.x + this->location.x - CHUNK_SIZE / 2, location.y + this->location.y - CHUNK_SIZE / 2, location.z }, dimensionId );
    return 0;
}

void Chunk::api( Framework::StreamReader* zRequest, NetworkResponse* zResponse )
{
    // TODO: answer api messages
}

Framework::Either<Block*, int> Chunk::zBlockAt( Framework::Vec3<int> location ) const
{
    int index = (location.x * CHUNK_SIZE + location.y) * WORLD_HEIGHT + location.z;
    assert( index < CHUNK_SIZE* CHUNK_SIZE* WORLD_HEIGHT );
    if( blocks[ index ] )
        return blocks[ index ];
    else
        return (int)blockIds[ index ];
}

const Block* Chunk::zBlockConst( Framework::Vec3<int> location ) const
{
    auto b = zBlockAt( location );
    if( b.isA() )
        return b;
    if( b.getB() )
        return StaticRegistry<BlockType>::INSTANCE.zElement( b.getB() )->zDefault();
    return 0;
}

void Chunk::instantiateBlock( Framework::Vec3<int> location )
{
    auto b = zBlockAt( location );
    if( b.isA() )
        return;
    if( !b.getB() )
        generateBlock( location );
    b = zBlockAt( location );
    if( b.isB() )
        putBlockAt( location, StaticRegistry<BlockType>::INSTANCE.zElement( b.getB() )->createBlockAt( { location.x + this->location.x - CHUNK_SIZE / 2, location.y + this->location.y - CHUNK_SIZE / 2, location.z }, 0 ) );
}

void Chunk::generateBlock( Framework::Vec3<int> location )
{
    int index = (location.x * CHUNK_SIZE + location.y) * WORLD_HEIGHT + location.z;
    if( blockIds[ index ] )
        return;
    auto generated = Game::INSTANCE->zGenerator()->generateSingleBlock( { location.x + this->location.x - CHUNK_SIZE / 2, location.y + this->location.y - CHUNK_SIZE / 2, location.z }, dimensionId );
    if( generated.isA() )
        putBlockAt( location, generated );
    else
        putBlockTypeAt( location, generated );
}

void Chunk::putBlockAt( Framework::Vec3<int> location, Block* block )
{
    int index = (location.x * CHUNK_SIZE + location.y) * WORLD_HEIGHT + location.z;
    assert( index < CHUNK_SIZE* CHUNK_SIZE* WORLD_HEIGHT && index >= 0 );
    Block* old = blocks[ index ];
    if( block )
        blockIds[ index ] = (unsigned short)block->zBlockType()->getId();
    blocks[ index ] = block;
    Either<Block*, int> neighbor = zBlockNeighbor( location + getDirection( NORTH ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbour( SOUTH, block );
    if( block )
        block->setNeighbour( NORTH, neighbor );
    neighbor = zBlockNeighbor( location + getDirection( EAST ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbour( WEST, block );
    if( block )
        block->setNeighbour( EAST, neighbor );
    neighbor = zBlockNeighbor( location + getDirection( SOUTH ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbour( NORTH, block );
    if( block )
        block->setNeighbour( SOUTH, neighbor );
    neighbor = zBlockNeighbor( location + getDirection( WEST ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbour( EAST, block );
    if( block )
        block->setNeighbour( WEST, neighbor );
    neighbor = zBlockNeighbor( location + getDirection( TOP ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbour( BOTTOM, block );
    if( block )
        block->setNeighbour( TOP, neighbor );
    neighbor = zBlockNeighbor( location + getDirection( BOTTOM ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbour( TOP, block );
    if( block )
        block->setNeighbour( BOTTOM, neighbor );
    if( old )
        old->release();
}

void Chunk::putBlockTypeAt( Framework::Vec3<int> location, int type )
{
    int index = (location.x * CHUNK_SIZE + location.y) * WORLD_HEIGHT + location.z;
    assert( index < CHUNK_SIZE* CHUNK_SIZE* WORLD_HEIGHT );
    blockIds[ index ] = (unsigned short)type;
    Either<Block*, int> neighbor = zBlockNeighbor( location + getDirection( NORTH ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbourType( SOUTH, type );
    neighbor = zBlockNeighbor( location + getDirection( EAST ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbourType( WEST, type );
    neighbor = zBlockNeighbor( location + getDirection( SOUTH ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbourType( NORTH, type );
    neighbor = zBlockNeighbor( location + getDirection( WEST ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbourType( EAST, type );
    neighbor = zBlockNeighbor( location + getDirection( TOP ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbourType( BOTTOM, type );
    neighbor = zBlockNeighbor( location + getDirection( BOTTOM ) );
    if( neighbor.isA() )
        ((Block*)neighbor)->setNeighbourType( TOP, type );
}

void Chunk::setNeighbor( Direction dir, Chunk* zChunk )
{
    zNeighbours[ getDirectionIndex( dir ) ] = zChunk;
    for( int i = 0; i < CHUNK_SIZE; i++ )
    {
        for( int z = 0; z < WORLD_HEIGHT; z++ )
        {
            if( dir == NORTH )
            {
                int index = i * CHUNK_SIZE * WORLD_HEIGHT + z;
                if( blocks[ index ] )
                {
                    int j = (i * CHUNK_SIZE + CHUNK_SIZE - 1) * WORLD_HEIGHT + z;
                    if( zChunk && zChunk->blocks[ j ] )
                        blocks[ index ]->setNeighbour( NORTH, zChunk->blocks[ j ] );
                    else
                    {
                        blocks[ index ]->setNeighbour( NORTH, 0 );
                        blocks[ index ]->setNeighbourType( NORTH, zChunk ? zChunk->blockIds[ j ] : 0 );
                    }
                }
            }
            else if( dir == EAST )
            {
                int index = ((CHUNK_SIZE - 1) * CHUNK_SIZE + i) * WORLD_HEIGHT + z;
                if( blocks[ index ] )
                {
                    int j = i * WORLD_HEIGHT + z;
                    if( zChunk && zChunk->blocks[ j ] )
                        blocks[ index ]->setNeighbour( EAST, zChunk->blocks[ j ] );
                    else
                    {
                        blocks[ index ]->setNeighbour( EAST, 0 );
                        blocks[ index ]->setNeighbourType( EAST, zChunk ? zChunk->blockIds[ j ] : 0 );
                    }
                }
            }
            else if( dir == SOUTH )
            {
                int index = (i * CHUNK_SIZE + CHUNK_SIZE - 1) * WORLD_HEIGHT + z;
                if( blocks[ index ] )
                {
                    int j = i * CHUNK_SIZE * WORLD_HEIGHT + z;
                    if( zChunk && zChunk->blocks[ j ] )
                        blocks[ index ]->setNeighbour( SOUTH, zChunk->blocks[ j ] );
                    else
                    {
                        blocks[ index ]->setNeighbour( SOUTH, 0 );
                        blocks[ index ]->setNeighbourType( SOUTH, zChunk ? zChunk->blockIds[ j ] : 0 );
                    }
                }
            }
            else if( dir == WEST )
            {
                int index = i * WORLD_HEIGHT + z;
                if( blocks[ index ] )
                {
                    int j = ((CHUNK_SIZE - 1) * CHUNK_SIZE + i) * WORLD_HEIGHT + z;
                    if( zChunk && zChunk->blocks[ j ] )
                        blocks[ index ]->setNeighbour( WEST, zChunk->blocks[ j ] );
                    else
                    {
                        blocks[ index ]->setNeighbour( WEST, 0 );
                        blocks[ index ]->setNeighbourType( WEST, zChunk ? zChunk->blockIds[ j ] : 0 );
                    }
                }
            }
        }
    }
}

void Chunk::load( Framework::StreamReader* zReader )
{
    unsigned short id = 0;
    zReader->lese( (char*)&id, 2 );
    Framework::Vec3<int> pos;
    bool d = 0;
    while( id )
    {
        zReader->lese( (char*)&pos.x, 4 );
        zReader->lese( (char*)&pos.y, 4 );
        zReader->lese( (char*)&pos.z, 4 );
        zReader->lese( (char*)&d, 1 );
        if( d )
            putBlockAt( pos, StaticRegistry<BlockType>::INSTANCE.zElement( id )->loadBlock( Framework::Vec3<int>( pos.x + location.x - CHUNK_SIZE / 2, pos.y + location.y - CHUNK_SIZE / 2, pos.z ), zReader ) );
        else
            putBlockTypeAt( pos, id );

        zReader->lese( (char*)&id, 2 );
    }
}

void Chunk::save( Framework::StreamWriter* zWriter, StreamTarget target )
{
    for( int x = 0; x < CHUNK_SIZE; x++ )
    {
        for( int y = 0; y < CHUNK_SIZE; y++ )
        {
            for( int z = 0; z < WORLD_HEIGHT; z++ )
            {
                int index = (x * CHUNK_SIZE + y) * WORLD_HEIGHT + z;
                unsigned short blockType = blocks[ index ] ? (unsigned short)blocks[ index ]->zBlockType()->getId() : blockIds[ index ];
                if( blockType )
                {
                    bool visible = target == StreamTarget::FULL;
                    if( !visible )
                    {
                        if( !blocks[ index ] )
                        {
                            if( CONST_BLOCK( 0, blockIds[ index ] )->isTransparent() || CONST_BLOCK( 0, blockIds[ index ] )->isPassable() )
                                visible = 1;
                            else
                            {
                                for( int d = 0; d < 6 && !visible; d++ )
                                {
                                    auto n = zBlockNeighbor( getDirection( (Directions)getDirectionFromIndex( d ) ) + Framework::Vec3<int>( x, y, z ) );
                                    if( n.isA() && (((Block*)n)->isPassable() || ((Block*)n)->isTransparent()) )
                                        visible = 1;
                                    if( n.isB() && (CONST_BLOCK( 0, n )->isTransparent() || CONST_BLOCK( 0, n )->isPassable()) )
                                        visible = 1;
                                }
                            }
                        }
                        else
                            visible = blocks[ index ]->isVisible();
                    }
                    if( target == StreamTarget::FULL || (visible && (blocks[ index ] || blockType != AirBlockBlockType::ID)) )
                    {
                        zWriter->schreibe( (char*)&blockType, 2 );
                        zWriter->schreibe( (char*)&x, 4 );
                        zWriter->schreibe( (char*)&y, 4 );
                        zWriter->schreibe( (char*)&z, 4 );
                        if( blocks[ index ] )
                        {
                            bool d = 1;
                            zWriter->schreibe( (char*)&d, 1 );
                            StaticRegistry<BlockType>::INSTANCE.zElement( blockType )->saveBlock( blocks[ index ], zWriter );
                        }
                        else
                        {
                            bool d = 0;
                            zWriter->schreibe( (char*)&d, 1 );
                        }
                    }
                }
            }
        }
    }
    unsigned short end = 0;
    zWriter->schreibe( (char*)&end, 2 );
}

void Chunk::removeUnusedBlocks()
{
    for( int i = 0; i < CHUNK_SIZE * CHUNK_SIZE * WORLD_HEIGHT; i++ )
    {
        if( blocks[ i ] )
        {
            if( !blocks[ i ]->isVisible() )
            {
                int x = (i / WORLD_HEIGHT) / CHUNK_SIZE;
                int y = (i / WORLD_HEIGHT) % CHUNK_SIZE;
                int z = i % WORLD_HEIGHT;
                putBlockAt( { x,y,z }, 0 );
                putBlockTypeAt( { x, y, z }, NoBlockBlockType::ID );
            }
        }
        else if( blockIds[ i ] )
        {
            int x = (i / WORLD_HEIGHT) / CHUNK_SIZE;
            int y = (i / WORLD_HEIGHT) % CHUNK_SIZE;
            int z = i % WORLD_HEIGHT;
            bool visible = 0;
            if( CONST_BLOCK( 0, blockIds[ i ] )->isTransparent() || CONST_BLOCK( 0, blockIds[ i ] )->isPassable() )
                visible = 1;
            else
            {
                for( int d = 0; d < 6 && !visible; d++ )
                {
                    auto n = zBlockNeighbor( getDirection( (Directions)getDirectionFromIndex( d ) ) + Framework::Vec3<int>( x, y, z ) );
                    if( n.isA() && (((Block*)n)->isPassable() || ((Block*)n)->isTransparent()) )
                        visible = 1;
                    if( n.isB() && (CONST_BLOCK( 0, n )->isTransparent() || CONST_BLOCK( 0, n )->isPassable()) )
                        visible = 1;
                }
            }
            if( !visible )
            {
                putBlockAt( { x,y,z }, 0 );
                putBlockTypeAt( { x, y, z }, NoBlockBlockType::ID );
            }
        }
    }
    int count = 0;
    for( int i = 0; i < CHUNK_SIZE * CHUNK_SIZE * WORLD_HEIGHT; i++ )
    {
        if( blockIds[ i ] && blockIds[ i ] != AirBlockBlockType::ID )
            count++;
    }
    std::cout << "chunk " << location.x << ", " << location.y << " was generated with " << count << " blocks.\n";
}

int Chunk::getDimensionId() const
{
    return dimensionId;
}

Framework::Punkt Chunk::getCenter() const
{
    return location;
}

Framework::Vec3<int> Chunk::getMin() const
{
    return { location.x - CHUNK_SIZE / 2, location.y - CHUNK_SIZE / 2, 0 };
}

Framework::Vec3<int> Chunk::getMax() const
{
    return { location.x + CHUNK_SIZE / 2, location.y + CHUNK_SIZE / 2, WORLD_HEIGHT };
}

void Chunk::prepareRemove()
{
    added = 0;
    for( int i = 0; i < 4; i++ )
    {
        if( zNeighbours[ i ] )
        {
            zNeighbours[ i ]->setNeighbor( getOppositeDirection( getDirectionFromIndex( i ) ), 0 );
            zNeighbours[ i ] = 0;
        }
    }
}

void Chunk::setAdded()
{
    added = 1;
}

void Chunk::addView( Entity* zEntity )
{
    cs.lock();
    bool found = 0;
    for( Entity* e : views )
    {
        if( e == zEntity )
        {
            found = 1;
            break;
        }
    }
    if( !found )
        views.add( zEntity );
    cs.unlock();
}

void Chunk::removeView( Entity* zEntity )
{
    cs.lock();
    int i = 0;
    for( Entity* e : views )
    {
        if( e == zEntity )
        {
            views.remove( i );
            break;
        }
        i++;
    }
    cs.unlock();
}

bool Chunk::hasView( Entity* zEntity )
{
    cs.lock();
    for( Entity* e : views )
    {
        if( e == zEntity )
        {
            cs.unlock();
            return 1;
        }
    }
    cs.unlock();
    return 0;
}

bool Chunk::hasViews() const
{
    return views.getEintragAnzahl() > 0;
}