/* ---------------------------------------------------------------------------
 * Truevision Targa Reader/Writer
 * $Id: targa.h,v 1.7 2003/06/21 09:30:53 emikulic Exp $
 *
 * Copyright (C) 2001-2003, Emil Mikulic.
 *
 * Source and binary redistribution of this code, with or without
 * changes, for free or for profit, is allowed as long as this copyright
 * notice is kept intact.  Modified versions have to be clearly marked
 * as modified.
 *
 * This code is provided without any warranty.  The copyright holder is
 * not liable for anything bad that might happen as a result of the
 * code.
 * -------------------------------------------------------------------------*/

/*
 * preso da http://dmr.ath.cx/gfx/targa/
 * modificato da gmt
 *
 */

#ifndef _TARGA_H_
#define _TARGA_H_

#include <stdio.h>
#ifndef _MSC_VER
#include <inttypes.h>
#else /* MSVC */
typedef unsigned __int8 uint8_t;
typedef unsigned __int16 uint16_t;
typedef unsigned __int32 uint32_t;
#endif

#define BIT(index) (1 << (index))

#ifdef _BIG_ENDIAN
#define htole16(x) ((((x)&0x00FF) << 8) | (((x)&0xFF00) >> 8))
#define letoh16(x) htole16(x)
#else /* little endian */
#define htole16(x) (x)
#define letoh16(x) (x)
#endif /* endianness */

/* Targa image and header fields -------------------------------------------*/
typedef struct
	{
	/* Note that Targa is stored in little-endian order */
	uint8_t image_id_length;

	uint8_t color_map_type;
/* color map = palette */
#define TGA_COLOR_MAP_ABSENT 0
#define TGA_COLOR_MAP_PRESENT 1

	uint8_t image_type;
#define TGA_IMAGE_TYPE_NONE 0		  /* no image data */
#define TGA_IMAGE_TYPE_COLORMAP 1	 /* uncompressed, color-mapped */
#define TGA_IMAGE_TYPE_BGR 2		  /* uncompressed, true-color */
#define TGA_IMAGE_TYPE_MONO 3		  /* uncompressed, black and white */
#define TGA_IMAGE_TYPE_COLORMAP_RLE 9 /* run-length, color-mapped */
#define TGA_IMAGE_TYPE_BGR_RLE 10	 /* run-length, true-color */
#define TGA_IMAGE_TYPE_MONO_RLE 11	/* run-length, black and white */

	/* color map specification */
	uint16_t color_map_origin; /* index of first entry */
	uint16_t color_map_length; /* number of entries included */
	uint8_t color_map_depth;   /* number of bits per entry */

	/* image specification */
	uint16_t origin_x;
	uint16_t origin_y;
	uint16_t width;
	uint16_t height;
	uint8_t pixel_depth;

	uint8_t image_descriptor;
/* bits 0,1,2,3 - attribute bits per pixel
     * bit  4       - set if image is stored right-to-left
     * bit  5       - set if image is stored top-to-bottom
     * bits 6,7     - unused (must be set to zero)
     */
#define TGA_ATTRIB_BITS (uint8_t)(BIT(0) | BIT(1) | BIT(2) | BIT(3))
#define TGA_R_TO_L_BIT (uint8_t) BIT(4)
#define TGA_T_TO_B_BIT (uint8_t) BIT(5)
#define TGA_UNUSED_BITS (uint8_t)(BIT(6) | BIT(7))
	/* Note: right-to-left order is not honored by some Targa readers */

	uint8_t *image_id;
	/* The length of this field is given in image_id_length, it's read raw
     * from the file so it's not not guaranteed to be zero-terminated.  If
     * it's not NULL, it needs to be deallocated.  see: tga_free_buffers()
     */

	uint8_t *color_map_data;
	/* See the "color map specification" fields above.  If not NULL, this
     * field needs to be deallocated.  see: tga_free_buffers()
     */

	uint8_t *image_data;
	/* Follows image specification fields (see above) */

	/* Extension area and developer area are silently ignored.  The Targa 2.0
     * spec says we're not required to read or write them.
     */

} tga_image;

/* For decoding header bits ------------------------------------------------*/
uint8_t tga_get_attribute_bits(const tga_image *tga);
int tga_is_right_to_left(const tga_image *tga);
int tga_is_top_to_bottom(const tga_image *tga);
int tga_is_colormapped(const tga_image *tga);
int tga_is_rle(const tga_image *tga);
int tga_is_mono(const tga_image *tga);

/* Error handling ----------------------------------------------------------*/
typedef enum {
	TGA_NOERR,
	TGAERR_FOPEN,
	TGAERR_EOF,
	TGAERR_WRITE,
	TGAERR_CMAP_TYPE,
	TGAERR_IMG_TYPE,
	TGAERR_NO_IMG,
	TGAERR_CMAP_MISSING,
	TGAERR_CMAP_PRESENT,
	TGAERR_CMAP_LENGTH,
	TGAERR_CMAP_DEPTH,
	TGAERR_ZERO_SIZE,
	TGAERR_PIXEL_DEPTH,
	TGAERR_NO_MEM,
	TGAERR_NOT_CMAP,
	TGAERR_RLE,
	TGAERR_INDEX_RANGE,
	TGAERR_MONO
} tga_result;

const char *tga_error(const tga_result errcode);

/* Load/save ---------------------------------------------------------------*/
tga_result tga_read(tga_image *dest, const char *filename);
tga_result tga_read_from_FILE(tga_image *dest, FILE *fp);
tga_result tga_write(const char *filename, const tga_image *src);
tga_result tga_write_to_FILE(FILE *fp, const tga_image *src);

/* Convenient writing functions --------------------------------------------*/
tga_result tga_write_mono(const char *filename, uint8_t *image,
						  const uint16_t width, const uint16_t height);

tga_result tga_write_mono_rle(const char *filename, uint8_t *image,
							  const uint16_t width, const uint16_t height);

tga_result tga_write_bgr(const char *filename, uint8_t *image,
						 const uint16_t width, const uint16_t height, const uint8_t depth);

tga_result tga_write_bgr_rle(const char *filename, uint8_t *image,
							 const uint16_t width, const uint16_t height, const uint8_t depth);

/* These functions will use tga_swap_red_blue to MODIFY your image data */
tga_result tga_write_rgb(const char *filename, uint8_t *image,
						 const uint16_t width, const uint16_t height, const uint8_t depth);

tga_result tga_write_rgb_rle(const char *filename, uint8_t *image,
							 const uint16_t width, const uint16_t height, const uint8_t depth);

/* Manipulation ------------------------------------------------------------*/
tga_result tga_flip_horiz(tga_image *img);
tga_result tga_flip_vert(tga_image *img);
tga_result tga_color_unmap(tga_image *img);

uint8_t *tga_find_pixel(const tga_image *img, uint16_t x, uint16_t y);
tga_result tga_unpack_pixel(const uint8_t *src, const uint8_t bits,
							uint8_t *b, uint8_t *g, uint8_t *r, uint8_t *a);
tga_result tga_pack_pixel(uint8_t *dest, const uint8_t bits,
						  const uint8_t b, const uint8_t g, const uint8_t r, const uint8_t a);

tga_result tga_desaturate(tga_image *img,
						  const int cr, const int cg, const int cb, const int dv);
tga_result tga_desaturate_rec_601_1(tga_image *img);
tga_result tga_desaturate_rec_709(tga_image *img);
tga_result tga_desaturate_itu(tga_image *img);
tga_result tga_desaturate_avg(tga_image *img);
tga_result tga_convert_depth(tga_image *img, const uint8_t bits);
tga_result tga_swap_red_blue(tga_image *img);

void tga_free_buffers(tga_image *img);

#ifndef TGA_KEEP_MACROS /* useful for targa.c */
#undef htole16
#undef letoh16
#endif

#endif /* !_TARGA_H_ */
/* vim:set tabstop=4 shiftwidth=4 textwidth=78 expandtab: */