starlight.h

#ifndef __LIB_STARLIGHT__
#define __LIB_STARLIGHT__

#include <stdint.h>
#include <stdbool.h>

#include <string.h>

#include <stdio.h> // printf only

typedef enum {
    STARLIGHT_S_SUCCESS = 0,
    STARLIGHT_S_UNKNOWN_FORMAT,
    STARLIGHT_S_CORRUPT_DATA,
    STARLIGHT_S_OUTPUT_DATA_IS_NULL,
    STARLIGHT_S_BUFFER_IS_NULL,
    STARLIGHT_S_MALLOC_FAILED,
    STARLIGHT_S_NOT_IMPLEMENTED,
    STARLIGHT_S_LENGTH,
} starlight_status_t;


typedef enum {
    STARLIGHT_F_PNG = 10,
    STARLIGHT_F_LENGTH,
} starlight_image_format_t;

typedef struct starlight_output_t {
    uint32_t width;
    uint32_t height;
    uint32_t x;
    uint32_t y;
} StarlightOutput;

typedef struct starlight_png_detail_t {
    uint8_t bit_depth;
    uint8_t color_type;
    uint8_t compression_method;
    uint8_t filter_method;
    uint8_t interlace_method;

    bool z_header_done;
    uint8_t z_comp_method;
    uint8_t z_comp_info;
    uint32_t z_win_size;
    uint8_t z_comp_level;
    uint8_t bpp; // byte per pixel

    // state variables
    uint64_t sx;
    uint64_t sy;
} StarlightPngDetail;

typedef struct starlight_buffer_t {
    uint8_t bdx; // bit index
    uint8_t *s; // start
    uint8_t *c; // cursor
    uint8_t *e; // end
    uint64_t l; // length
} StarlightBuffer;

typedef struct starlight_t {
    StarlightBuffer raw; // raw image data - full file input
    StarlightBuffer cmp; // raw compressed data
    StarlightBuffer out; // output pixels in RGBA

    bool buffer_moved;

    starlight_image_format_t format;
    StarlightPngDetail png;

    uint32_t width;
    uint32_t height;

    StarlightOutput output;

    starlight_status_t (*loader)(struct starlight_t *starlight);
} Starlight;


/* common { */
uint32_t starlight_calc_crc(uint8_t *buffer, uint64_t length);

/* } */

/* starlight { */
starlight_status_t starlight_load(Starlight *starlight);
const char *starlight_status_string(starlight_status_t status);
/* } */

/* png { */
starlight_status_t starlight_inflate(
    StarlightBuffer *input,
    StarlightBuffer *output
);
bool starlight_png_check(Starlight *starlight);
starlight_status_t starlight_png_load_header(Starlight *starlight);
starlight_status_t starlight_png_loader(Starlight *starlight);
/* } */

#endif // __LIB_STARLIGHT__