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

/**
 * Maximum supported opset version
 */
#define MAX_OPSET_VERSION 20

/**
 * Execution mode
 */
enum ExecutionMode {
  /**
   * Fails immediately if it encounters an operator that is not implemented
   */
  FailFast = 1,
  /**
   * Continues execution if it encounters an operator that is not implemented, simply panicking when it encounters that operator
   */
  Continue = 0,
};
typedef int64_t ExecutionMode;

/**
 * Graph format
 */
enum GraphFormat {
  /**
   * No graph output
   */
  None = 0,
  /**
   * Graph output in JSON format, saved to graph.json
   */
  Json = 1,
  /**
   * Graph output in DOT format, saved to graph.dot
   */
  Dot = 2,
};
typedef int64_t GraphFormat;

enum Verbosity {
  Silent = -1,
  Minimal = 0,
  Informational = 1,
  Results = 2,
  Intermediate = 4,
};
typedef int64_t Verbosity;

typedef struct ModelProto ModelProto;

/**
 * Reads an ONNX model from a file
 *
 * Returns a pointer to a model, null if error, check last_error
 *
 * # Safety
 *
 * Should take a valid path as a C string
 */
struct ModelProto *read_onnx_model(const char *model_path);

/**
 * Frees a model
 *
 * Returns nothing, does nothing if given a null pointer
 *
 * # Safety
 *
 * Should take a valid pointer to a model
 */
void free_onnx_model(struct ModelProto *model);

/**
 * Returns the opset version of a model
 *
 * Returns MAX_OPSET_VERSION if no opset version is found
 *
 * Returns MAX_OPSET_VERSION if given a null pointer and sets last_error
 *
 * # Safety
 *
 * Should take a valid pointer to a model
 */
int64_t get_opset_version(const struct ModelProto *model);

/**
 * Runs a model given a path to a model directory, verbosity level (0-4), graph format (json / dot), and execution mode (failfast / continue)
 *
 * Returns true if successful, false if not
 *
 * Sets last_error if an error occurs
 *
 * # Safety
 *
 * Should take a valid path to a model directory as a C string
 *
 * Should take a valid verbosity level
 *
 * Should take a valid graph format
 *
 * Should take a valid execution mode
 */
bool run_model(const char *model_path,
               Verbosity verbosity,
               GraphFormat graph_format,
               ExecutionMode failfast);

/**
 * Returns a pointer to a C string containing the last error
 *
 * Returns a null pointer if no error is present
 *
 * # Safety
 *
 * Safe, returns a pointer to a C string, null if no error
 *
 * Valid until the next call to run_model
 */
const char *last_error(void);