/**
 * \file hvif-light.h
 * \author Hans-Jörg Schurr
 *
 * \brief Parse \a hvif images.
 *
 * This library provides functions for parsing Haiku Vector Icon
 * files. The parser should be able to parse any files generated by Haiku
 * as of April 2020. It is, however, wholly untested and should not be
 * used. It most likely contains horrible bugs. During parsing some
 * basic checks for consistency of the image data are performed. But
 * not everything is checked. For example, paths might be invalid.
 */

#ifndef HVIF_LIGHT_H
#define HVIF_LIGHT_H

#include <stdbool.h>
#include <stdio.h>

/** \typedef The result of parsing an image. */
typedef enum hvif_status
{
	SUCCESS = 0, /**< The image has been parsed into memory. */
	ERROR_EOF, /**< The file ended before parsing finished. */
	ERROR_NOMEM, /**< Not enough memory could be allocated. */
	ERROR_MAGIC, /**< The magic number of the file is wrong. */
	ERROR_STYLE, /**< Parsing a style failed. */
	ERROR_PATH, /**< Parsing a path failed. */
	ERROR_SHAPE /**< Parsing a shape failed. */
} hvif_status;

/**
 * \typedef Opaque structure to reference a parsed image.
 * 	An API to inspect the image will be provided later.
 */
typedef struct hvif_image hvif_image;

/**
 * \typedef Captures the result of parsing: a status code together with the
 * 	image.
 */
typedef struct hvif_result hvif_result;
struct hvif_result
{
	hvif_status status; /**< Indicates success or an error in parsing. */
	hvif_image* image; /**< The image structure. NULL if parsing failed. */
};

/**
 * \brief Parses a \a hvif image from a file.
 * \param[in] file A valid file handler.
 * \return A `hvif_result` structure. A status other then SUCCESS indicates
 * 	an error. In this case the image is NULL. Otherwise the image needs
 *	to be freed. A success does not indicate that the image is renderable.
 */
hvif_result hvif_from_file(FILE* file);

/**
 * \brief Frees the memory of the image datastructures.
 * \param[in] image An image pointer returned by a previous call to
 * 	`hvif_from_file`. Can be NULL.
 */
void hvif_free(hvif_image* image);

#endif /* HVIF_LIGHT_H */