/* Test the C++ API. 
 *
 * This isn't a full test suite, look in the Python area for that. This is
 * just supposed to check that the C++ binding is working. 
 *
 * compile with:
 *
 *      g++ -g -Wall test.cpp `pkg-config vips-cpp --cflags --libs`
 *
 * run with:
 *
 * 	./a.out ~/pics/k2.jpg ~/pics/shark.jpg --vips-leak
 * 	valgrind --leak-check=yes ./a.out ~/pics/k2.jpg ~/pics/shark.jpg 
 * 	rm x.tif
 *
 */

/*
#define VIPS_DEBUG
#define VIPS_DEBUG_VERBOSE
 */

#include <stdlib.h>

#include <vips/vips8>

using namespace vips;

bool
equal_vector( std::vector<double> a, std::vector<double> b )
{
	for( unsigned int i = 0; i < a.size(); i++ ) 
		if( fabs( a[i] - b[i] ) > 0.001 ) {
			printf( "vectors differ at %u: should be [", i );
			for( unsigned int i = 0; i < a.size(); i++ ) {
				if( i > 0 )
					printf( ", " ); 
				printf( "%g", a[i] );
			}
			printf( "], is [" );
			for( unsigned int i = 0; i < a.size(); i++ ) {
				if( i > 0 )
					printf( ", " ); 
				printf( "%g", a[i] );
			}
			printf( "]\n" );

			return( false );
		}

	return( true );
}

bool
equal_double( double a, double b )
{
	if( fabs( a - b ) > 0.001 ) {
		printf( "doubles differ: should be %g, is %g\n", a, b );
		return( false );
	}

	return( true ); 
}

/* We can't do this with a template, I think we'd need partially-parameterised
 * template, which is C++11 only.
 */

/* Only test a few points and only test uchar: we are just testing the C++ 
 * overloads, we rely on the python test suite for testing the underlying 
 * vips operators.
 */
#define TEST_BINARY( OPERATOR ) \
void \
test_binary_##OPERATOR( VImage left, VImage right ) \
{ \
	for( int x = 10; x < 30; x += 10 ) {  \
		std::vector<double> p_left = left.getpoint( x, x );  \
		std::vector<double> p_right = right.getpoint( x, x );  \
		std::vector<double> p_result =  \
			OPERATOR<std::vector<double>,  \
				std::vector<double>,  \
				std::vector<double> >(p_left, p_right ); \
 		\
		VImage im_result; \
		std::vector<double> p_im_result; \
 		\
		/* test: image = image OP image \
		 */ \
		im_result = OPERATOR<VImage, VImage, VImage>( left, right ); \
		p_im_result = im_result.getpoint( x, x ); \
 		\
		if( !equal_vector( p_result, p_im_result ) ) { \
			printf( #OPERATOR \
				"(VImage, VImage) failed at (%d, %d)\n", \
				x, x ); \
			abort(); \
		} \
 		\
		/* test: image = image OP vec \
		 */ \
		im_result = \
			OPERATOR<VImage, \
				VImage, std::vector<double> >( left, p_right );\
		p_im_result = im_result.getpoint( x, x ); \
 		\
		if( !equal_vector( p_result, p_im_result ) ) { \
			printf( #OPERATOR \
				"(VImage, vector) failed at (%d, %d)\n", \
				x, x ); \
			abort(); \
		} \
 		\
		/* test: image = vec OP image \
		 */ \
		im_result = \
			OPERATOR<VImage, std::vector<double>, \
				VImage>( p_left, right );  \
		p_im_result = im_result.getpoint( x, x ); \
 		\
		if( !equal_vector( p_result, p_im_result ) ) { \
			printf( #OPERATOR \
				"(vector, VImage) failed at (%d, %d)\n", \
				x, x ); \
			abort(); \
		} \
 		\
		/* test: image = image OP double \
		 */ \
		for( unsigned int i = 0; i < p_right.size(); i++ ) { \
			im_result = \
				OPERATOR<VImage,  \
					VImage, double>( left, p_right[i] ); \
			p_im_result = im_result.getpoint( x, x ); \
 			\
			if( !equal_double( p_result[i], p_im_result[i] ) ) { \
				printf( #OPERATOR \
					"(VImage, double) failed at " \
					"(%d, %d)\n", \
					x, x ); \
				abort(); \
			} \
		} \
 		\
		/* test: image = double OP image  \
		 */ \
		for( unsigned int i = 0; i < p_left.size(); i++ ) { \
			im_result = \
				OPERATOR<VImage, \
					double, VImage>( p_left[i], right ); \
			p_im_result = im_result.getpoint( x, x ); \
 			\
			if( !equal_double( p_result[i], p_im_result[i] ) ) { \
				printf( #OPERATOR \
					"(double, VImage) failed at " \
					"(%d, %d)\n", \
					x, x ); \
				abort(); \
			} \
		} \
	} \
}

// eg. double = double + double
// or image = double + image
template <typename A, typename B, typename C> 
A test_add( B left, C right )
{
	return( left + right );
}

template <typename T>
std::vector<T> operator+(std::vector<T> &v1, const std::vector<T> &v2) 
{
	std::vector<T> result( v1.size() );

	for( unsigned int i = 0; i < v1.size(); i++ )
		result[i] = v1[i] + v2[i];

	return( result ); 
}

TEST_BINARY( test_add );

template <typename A, typename B, typename C> 
A test_subtract( B left, C right )
{
	return( left - right );
}

template <typename T>
std::vector<T> operator-(std::vector<T> &v1, const std::vector<T> &v2) 
{
	std::vector<T> result( v1.size() );

	for( unsigned int i = 0; i < v1.size(); i++ )
		result[i] = v1[i] - v2[i];

	return( result ); 
}

TEST_BINARY( test_subtract );

template <typename A, typename B, typename C> 
A test_multiply( B left, C right )
{
	return( left * right );
}

template <typename T>
std::vector<T> operator*(std::vector<T> &v1, const std::vector<T> &v2) 
{
	std::vector<T> result( v1.size() );

	for( unsigned int i = 0; i < v1.size(); i++ )
		result[i] = v1[i] * v2[i];

	return( result ); 
}

TEST_BINARY( test_multiply );

template <typename A, typename B, typename C> 
A test_divide( B left, C right )
{
	return( left / right );
}

template <typename T>
std::vector<T> operator/(std::vector<T> &v1, const std::vector<T> &v2) 
{
	std::vector<T> result( v1.size() );

	for( unsigned int i = 0; i < v1.size(); i++ )
		result[i] = v1[i] / v2[i];

	return( result ); 
}

TEST_BINARY( test_divide );

int
main( int argc, char **argv )
{
	if( VIPS_INIT( argv[0] ) )
		vips_error_exit( NULL ); 

	VImage left = VImage::new_from_file( argv[1] ); 
	VImage right = VImage::new_from_file( argv[2] ); 

{ 
	printf( "testing constant args ...\n" ); 

	double a[] = { 1.0, 2.0, 3.0 }; 
	double b[] = { 4.0, 5.0, 6.0 }; 

	std::vector<double> avec( a, a + VIPS_NUMBER( a ) ); 
	std::vector<double> bvec( b, b + VIPS_NUMBER( b ) ); 

	VImage out = left.linear( avec, bvec ); 

	out.write_to_file( "x.tif" );
}

{
	printf( "testing operator overloads ...\n" ); 
	test_binary_test_add( left, right );
	test_binary_test_subtract( left, right );
	test_binary_test_multiply( left, right );
	test_binary_test_divide( left, right );

	VImage band_one = left[1];

	std::vector<double> point = left(0, 0);
}

{
	// write to a formatted memory buffer
	printf( "testing formatted memory write ...\n" ); 

	size_t size;
	void *buf;
	left.write_to_buffer( ".png", &buf, &size );
	printf( "written to memory %p in png format, %zu bytes\n", buf, size );

	// load from the formatted memory area
	VImage im = VImage::new_from_buffer( buf, size, "" );
	printf( "loaded from memory, %d x %d pixel image\n", 
		im.width(), im.height() ); 

	// write back to a file
	im.write_to_file( "x.tif" );
	printf( "written back to x.tif\n" ); 

	g_free( buf ); 
}

{
	// write to a vanilla memory buffer
	printf( "testing memory array write ...\n" ); 

	size_t size;
	void *buf;
	buf = left.write_to_memory( &size );
	printf( "written to memory %p as an array, %zu bytes\n", buf, size );

	// load from the memory array
	VImage im = VImage::new_from_memory( buf, size, 
		left.width(), left.height(), left.bands(), left.format() );
	printf( "loaded from memory array, %d x %d pixel image\n", 
		im.width(), im.height() ); 

	// write back to a file
	im.write_to_file( "x.tif" );
	printf( "written back to x.tif\n" ); 

	g_free( buf ); 
}

{
	printf( "testing double return from operation ...\n" ); 

	double avg = left.avg(); 

	printf( "left.avg() = %g\n", avg ); 
}

{ 
	printf( "testing optional enum args ...\n" ); 

	VImage out = left.embed( 10, 10, 1000, 1000, 
		VImage::option()->set( "extend", "copy" ) );

	out.write_to_file( "x.tif" );
}

{ 
	printf( "testing multiple image return ...\n" ); 

	VImage rows; 
	VImage cols = left.profile( &rows );
	rows.write_to_file( "x.tif" );
	cols.write_to_file( "x.tif" );
}

{ 
	printf( "testing interpolators ...\n" ); 

	VInterpolate interp = VInterpolate::new_from_name( "nohalo" );

	VImage out; 

	out = left.resize( 0.2, 
		VImage::option()->set( "interpolate", interp ) );
	out.write_to_file( "x.tif" );
}

{ 
	printf( "testing new_from_image() ...\n" ); 

	VImage out = left.new_from_image( 128 );

	out.write_to_file( "x.tif" );
}

	printf( "all tests passed\n" ); 

        return( 0 );
}