#ifndef NVML_GPU_H
#define NVML_GPU_H

#include <stddef.h>
#include <stdint.h>

#ifdef __cplusplus
extern "C" {
#endif

// GPU information structure
typedef struct {
    uint32_t index;
    char name[256];
    uint32_t utilization;        // GPU utilization percentage (0-100)
    uint64_t memory_used;        // Memory used in bytes
    uint64_t memory_total;       // Total memory in bytes
    uint32_t temperature;        // Temperature in Celsius
    uint32_t power_draw;         // Power draw in milliwatts
    uint32_t clock_sm;           // SM clock in MHz
    uint32_t clock_memory;       // Memory clock in MHz
    uint32_t pcie_gen;           // PCIe generation
    uint32_t pcie_width;         // PCIe link width
    char uuid[80];               // GPU UUID
    char vbios_version[32];      // VBIOS version
} gpu_info_t;

// Initialize NVML library
// Returns 0 on success, non-zero on failure
int gpu_init(void);

// Shutdown NVML library
void gpu_shutdown(void);

// Get number of GPUs
// Returns -1 on error, >= 0 on success
int gpu_get_count(void);

// Get GPU info by index
// Returns 0 on success, non-zero on failure
int gpu_get_info(uint32_t index, gpu_info_t* info);

// Get current utilization for a GPU
// Returns 0 on success, non-zero on failure
int gpu_get_utilization(uint32_t index, uint32_t* utilization);

// Get memory info for a GPU
// Returns 0 on success, non-zero on failure
int gpu_get_memory(uint32_t index, uint64_t* used, uint64_t* total);

// Get temperature for a GPU
// Returns 0 on success, non-zero on failure
int gpu_get_temperature(uint32_t index, uint32_t* temp);

// Check if NVML is available (runtime detection)
// Returns 1 if available, 0 if not
int gpu_is_available(void);

// Get last error message (thread-safe)
const char* gpu_last_error(void);

#ifdef __cplusplus
}
#endif

#endif // NVML_GPU_H