#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
#include "w32g_dib.h"

w32g_dib_t *dib_create (int width, int height )
{
	BITMAPINFO bi;
	w32g_dib_t *dib;

	dib = (w32g_dib_t *) malloc ( sizeof (w32g_dib_t) );
	if ( dib == NULL ) return NULL;
	memset ( dib, 0, sizeof (w32g_dib_t) );

	memset ( &bi, 0, sizeof (BITMAPINFO) );
	bi.bmiHeader.biSize			= sizeof (BITMAPINFOHEADER);
	bi.bmiHeader.biWidth		= width;
	bi.bmiHeader.biHeight		= -height;
	bi.bmiHeader.biPlanes		= 1;
	bi.bmiHeader.biBitCount		= 8;
	bi.bmiHeader.biCompression	= BI_RGB;
	bi.bmiHeader.biSizeImage	= 0;
	bi.bmiHeader.biXPelsPerMeter= 0;
	bi.bmiHeader.biYPelsPerMeter= 0;
	bi.bmiHeader.biClrImportant = 0;
	bi.bmiHeader.biClrUsed		= 0;
	dib->hbmp = CreateDIBSection ( NULL, &bi, DIB_RGB_COLORS, (void **)&dib->bits, NULL, 0);
	dib->width = width;
	dib->height = height;
	dib->pals_max = 16;
	dib->modified_rect_max = 0;

	return dib;
}

void dib_free ( w32g_dib_t *dib )
{
	if ( dib == NULL )
		return;
	GdiFlush ();
	DeleteObject ( dib->hbmp );
	free ( dib );
}

void dib_add_modified_rect ( w32g_dib_t *dib, RECT *lprc )
{
	RECT rc;
	int i;
	for ( i = 0; i < dib->modified_rect_max; i ++ ) {
		if ( dib->modified_rect[i].left <= lprc->left && lprc->right <= dib->modified_rect[i].right
			&& dib->modified_rect[i].top <= lprc->top && lprc->bottom <= dib->modified_rect[i].bottom )
				return;
	}
	if ( dib->modified_rect_max >= W32G_DIB_MODIFIED_RECT_MAX ) {
		if ( UnionRect ( &rc, &dib->modified_rect[dib->modified_rect_max - 1], lprc ) )
			memcpy ( &dib->modified_rect[dib->modified_rect_max - 1], &rc, sizeof (RECT) );
	} else {
			memcpy ( &dib->modified_rect[dib->modified_rect_max], lprc, sizeof (RECT) );
			dib->modified_rect_max++;
	}
}

void dib_modified_rect_whole ( w32g_dib_t *dib )
{
	dib->modified_rect_max = 1;
	SetRect ( &dib->modified_rect[0], 0, 0, dib->width, dib->height );
}

void dib_set_pal1 ( w32g_dib_t *dib, int pal_index, RGBQUAD rq )
{
	HDC hmdc;

	if ( pal_index >= dib->pals_max )
		return;
	if ( memcmp ( &dib->pals[pal_index], &rq, sizeof (RGBQUAD) ) == 0 )
		return;
	memcpy ( &dib->pals[pal_index], &rq, sizeof (RGBQUAD) );

	GdiFlush ();
	hmdc = CreateCompatibleDC ( (HDC)NULL );
	SelectObject ( hmdc, dib->hbmp );
	SetDIBColorTable ( hmdc, pal_index, 1, &dib->pals[pal_index] );
	DeleteDC ( hmdc );

	dib_modified_rect_whole ( dib );
}

void dib_set_pals ( w32g_dib_t *dib, RGBQUAD *pals, int pals_max )
{
	int i;
	BOOL modified = FALSE;

	if ( pals_max <= 0 ) return;
	if ( pals_max >= dib->pals_max )
		pals_max = dib->pals_max;
	for ( i = 0; i < pals_max; i ++ ) {
		if ( memcmp ( &dib->pals[i], &pals[i], sizeof (RGBQUAD) ) != 0 ) {
			memcpy ( &dib->pals[i], &pals[i], sizeof (RGBQUAD) );
			modified = TRUE;
		}
	}
	if ( modified ) {
		HDC hmdc;
		GdiFlush ();
		hmdc = CreateCompatibleDC ( (HDC)NULL );
		SelectObject ( hmdc, dib->hbmp );
		SetDIBColorTable ( hmdc, 0, dib->pals_max, dib->pals );
		DeleteDC ( hmdc );
		dib_modified_rect_whole ( dib );
	}
}

void dib_apply ( w32g_dib_t *dib, HDC hdc )
{
	HDC hmdc;
	int i;
	if ( dib->modified_rect_max <= 0 ) return;
	GdiFlush ();
	hmdc = CreateCompatibleDC ( hdc );
	SelectObject ( hmdc, dib->hbmp );
	for ( i = 0; i < dib->modified_rect_max; i++ ) {
		RECT *lprc = &dib->modified_rect[i];
		BitBlt ( hdc, lprc->left, lprc->top, lprc->right - lprc->left, lprc->bottom - lprc->top,
			hmdc, lprc->left, lprc->top, SRCCOPY );
	}
	dib->modified_rect_max = 0;
	DeleteDC ( hmdc );
}