#include "Surface.h"

#ifdef WIN32
    #include <windows.h>
#endif
#include <memory.h>



Surface::Surface():
    pixels( NULL ),
    width( 0 ),
    height( 0 )
{
}



Surface::Surface( const Surface &copy ):
    pixels( NULL ),
    width( copy.width ),
    height( copy.height )
{
    if( width && height )
    {
        pixels = new unsigned char[ width * height * 4 ];
        memcpy( pixels, copy.pixels, width * height * 4 );
    }
}



Surface&
Surface::operator =( const Surface &copy )
{
    if( width && height )
    {
        delete[] pixels;
    }

    if( copy.width && copy.height )
    {
        width  = copy.width;
        height = copy.height;

        pixels = new unsigned char[ width * height * 4 ];
        memcpy( pixels, copy.pixels, width * height * 4 );
    }

    return *this;
}



Surface::~Surface()
{
    if( width && height )
    {
        delete[] pixels;
    }
}



Surface*
CreateSurface( const int width, const int height )
{
    Surface* image = new Surface();

    image->width   = width;
    image->height  = height;
    image->pixels  = new unsigned char[ width * height * 4 ];

    return image;
}



void
CopyToSurface( Surface* dest, const int x_d, const int y_d, Surface* src )
{
    if( dest == NULL || src == NULL )
    {
        return;
    }

    for( int y_from = y_d, y_to = y_d + src->height; y_from < y_to; ++y_from )
    {
        memcpy( dest->pixels + y_from * dest->width * 4 + x_d * 4, src->pixels + ( y_from - y_d ) * src->width * 4, src->width * 4 );
    }
}



Surface*
CreateSubSurface( const int x, const int y, const int width, const int height, Surface* surface )
{
    Surface* image = CreateSurface( width, height );

    if( surface != NULL )
    {
        for( int y_from = y, y_to = y + image->height; y_from < y_to; ++y_from )
        {
            memcpy( image->pixels + ( y_from - y ) * image->width * 4, surface->pixels + ( y_from * surface->width + x ) * 4, image->width * 4) ;
        }
    }

    return image;
}



Surface*
CreateSurfaceFrom( const int width, const int height, unsigned char* pixels )
{
    Surface* image = CreateSurface( width, height );

    if( pixels != NULL )
    {
        memcpy( image->pixels, pixels, width * height * 4 );
    }

    return image;
}



void
SetSurfaceSize( Surface* &surface, const int &width, const int &height )
{
    unsigned char* pixels = new unsigned char[ width * height * 4 ];
    memset( pixels, 0x00, width * height * 4 );

    for( int y = 0; y < height; y++ )
    {
        if( y < surface->height )
        {
            int size_to_copy = ( surface->width < width ) ? surface->width * 4 : width * 4;
            memcpy( pixels + y * width * 4, surface->pixels + y * surface->width * 4, size_to_copy );
        }
    }

    delete surface;
    surface = CreateSurfaceFrom( width, height, pixels );

    delete[] pixels;
}