#include <thread>
#include <unistd.h>
#include <stdlib.h>
#include "overlay.h"
#include "gpu.h"
#include "spdlog/spdlog.h"
#include "nlohmann/json.hpp"
#include <inttypes.h>
using json = nlohmann::json;

static bool init_intel = false;
struct gpuInfo gpu_info_intel {};
static char pid[10];
static FILE *fp;

// static void intelGpuThread(){
//     init_intel = true;
//     static char stdout_buffer[1024];
//     FILE* intel_gpu_top = popen("intel_gpu_top -J -s 500", "r");
//     int num_line = 0;
//     std::string buf;
//     int num_iterations = 0;
//     while (fgets(stdout_buffer, sizeof(stdout_buffer), intel_gpu_top)) {
//         if (num_line > 0)
//             buf += stdout_buffer;

//         num_line++;
//         if (strlen(stdout_buffer) < 4 && !strchr(stdout_buffer, '{') && !strchr(stdout_buffer, ',')) {
//             if (buf[0] != '{')
//                 buf = "{\n" + buf;

//             if (num_iterations > 0){
//                 buf += "\n}";
//                 json j = json::parse(buf);
//                 if  (j.contains("engines"))
//                     if (j["engines"].contains("Render/3D/0"))
//                         if (j["engines"]["Render/3D/0"].contains("busy"))
//                             gpu_info_intel.load = j["engines"]["Render/3D/0"]["busy"].get<int>();

//                 if (j.contains("frequency"))
//                     if (j["frequency"].contains("actual"))
//                         gpu_info_intel.CoreClock = j["frequency"]["actual"].get<int>();
//                 if (j.contains("power")){
//                     if (j["power"].contains("GPU"))
//                         gpu_info_intel.powerUsage = j["power"]["GPU"].get<float>();
//                     if (j["power"].contains("Package"))
//                         gpu_info_intel.apu_cpu_power = j["power"]["Package"].get<float>();
//                 }

//             }
//             buf = "";
//             num_line = 0;
//         }
//         num_iterations++;
//     }

//     int exitcode = pclose(intel_gpu_top) / 256;
//     if (exitcode > 0){
//         if (exitcode == 127)
//         SPDLOG_INFO("Failed to open '{}'", "intel_gpu_top");

//         if (exitcode == 1)
//         SPDLOG_INFO("Missing permissions for '{}'", "intel_gpu_top");

//         SPDLOG_INFO("Disabling gpu_stats");
//         _params->enabled[OVERLAY_PARAM_ENABLED_gpu_stats] = false;
//     }
// }

void getIntelGpuInfo(){
    static char path[100] = "/proc/";
    if (!init_intel){
        sprintf(pid, "%i", getpid());
        strcat(path, pid);
        strcat(path, "/fdinfo/8");
        fp = fopen(path, "r");
        init_intel = true;
    }

    fp = fopen(path, "r");
    static char line[100];
    static uint64_t busy_ns;
    static uint64_t prev_ns;
    static uint64_t busy_percent;
    while (fgets(line, sizeof(line), fp))
        sscanf(line, "drm-engine-render: %" PRId64 " ns", &busy_ns);

    if (busy_ns < prev_ns){
        fclose(fp);
        return; 
    }

    uint64_t busy_time_ns = busy_ns - prev_ns;
    busy_percent = busy_time_ns / 5000000;

    prev_ns = busy_ns;
    if (busy_percent > 100) busy_percent = 100;
    gpu_info_intel.load = busy_percent;
    gpu_info = gpu_info_intel;
    fclose(fp);
}