// Copyright 2013 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include <asm/hwcap.h>
#include <fstream>
#include <sstream>
#include <string>
#include <sys/auxv.h>
#include <unistd.h>

#include "Common/CPUDetect.h"
#include "Common/CommonTypes.h"
#include "Common/StringUtil.h"

const char procfile[] = "/proc/cpuinfo";

static std::string GetCPUString()
{
  const std::string marker = "Hardware\t: ";
  std::string cpu_string = "Unknown";

  std::string line;
  std::ifstream file(procfile);

  if (!file)
    return cpu_string;

  while (std::getline(file, line))
  {
    if (line.find(marker) != std::string::npos)
    {
      cpu_string = line.substr(marker.length());
      break;
    }
  }

  return cpu_string;
}

CPUInfo cpu_info;

CPUInfo::CPUInfo()
{
  Detect();
}

// Detects the various CPU features
void CPUInfo::Detect()
{
  // Set some defaults here
  // When ARMv8 CPUs come out, these need to be updated.
  HTT = false;
  OS64bit = true;
  CPU64bit = true;
  Mode64bit = true;
  vendor = VENDOR_ARM;

  // Get the information about the CPU
  num_cores = sysconf(_SC_NPROCESSORS_CONF);
  strncpy(cpu_string, GetCPUString().c_str(), sizeof(cpu_string));

  unsigned long hwcaps = getauxval(AT_HWCAP);
  bFP = hwcaps & HWCAP_FP;
  bASIMD = hwcaps & HWCAP_ASIMD;
  bAES = hwcaps & HWCAP_AES;
  bCRC32 = hwcaps & HWCAP_CRC32;
  bSHA1 = hwcaps & HWCAP_SHA1;
  bSHA2 = hwcaps & HWCAP_SHA2;
}

// Turn the CPU info into a string we can show
std::string CPUInfo::Summarize()
{
  std::string sum;
  if (num_cores == 1)
    sum = StringFromFormat("%s, %i core", cpu_string, num_cores);
  else
    sum = StringFromFormat("%s, %i cores", cpu_string, num_cores);

  if (bAES)
    sum += ", AES";
  if (bCRC32)
    sum += ", CRC32";
  if (bSHA1)
    sum += ", SHA1";
  if (bSHA2)
    sum += ", SHA2";
  if (CPU64bit)
    sum += ", 64-bit";

  return sum;
}
