#ifndef GPU_MONITOR_H
#define GPU_MONITOR_H

#include <string>
#include <vector>
#include <memory>

// Include NVML types for Linux
#ifdef __linux__
#include <nvml.h>
#endif

/// Structure containing GPU statistics
struct GpuStats {
    double utilizationPercent;      // GPU utilization percentage (0-100)
    double memoryUsedMB;            // Memory used in MB
    double memoryTotalMB;           // Total memory in MB
    int    deviceIndex;             // Index of the GPU device
};

/// Class for monitoring GPU utilization and memory
class GpuMonitor {
public:
    explicit GpuMonitor();
    ~GpuMonitor();

    /// Returns true if monitor is initialized and ready
    bool isReady() const;

    /// Gets the latest GPU statistics
    /// @param stats Reference to store the statistics
    /// @return true on success, false on failure
    bool getGpuStats(GpuStats &stats);

    /// Enables or disables GPU monitoring
    /// @param enabled Whether to enable monitoring
    void setEnabled(bool enabled);

    /// @return Whether GPU monitoring is enabled
    bool isEnabled() const;

private:
    // NVML forward declarations - will be dynamically linked
    struct nvmlDevice;
    struct nvmlStat;

    // Internal implementation details
    struct Impl {
        nvmlDevice_t device_;
        bool enabled_;
        bool ready_;

        Impl() : device_(nullptr), enabled_(true), ready_(false) {}

        ~Impl() {
            if (device_) {
                nvmlShutdown();
            }
        }

        bool initialize() {
            // Initialize NVML
            nvmlReturn_t result = nvmlInit();
            if (result != NVML_SUCCESS) {
                return false;
            }

            // Get default GPU device
            unsigned int deviceCount = 0;
            result = nvmlDeviceGetCount(&deviceCount);
            if (result != NVML_SUCCESS || deviceCount == 0) {
                return false;
            }

            if (deviceCount > 0) {
                result = nvmlDeviceGetHandleByIndex(0, &device_);
                if (result != NVML_SUCCESS) {
                    return false;
                }
                ready_ = true;
            }

            return ready_;
        }
    };

    std::unique_ptr<Impl> impl_;

    // Configuration
    bool enabled_ = true;
    bool ready_ = false;
};

#endif // GPU_MONITOR_H