#include "node.h"
#include "node_internals.h"
#include "node_errors.h"
#include "base_object.h"
#include "base_object-inl.h"
#include "env-inl.h"
#include "util-inl.h"
#include "uv.h"
#include "v8.h"

#if HAVE_INSPECTOR
#include "inspector_io.h"
#endif

#include <limits.h>  // PATH_MAX
#include <stdio.h>

#if defined(_MSC_VER)
#include <direct.h>
#include <io.h>
#define umask _umask
typedef int mode_t;
#else
#include <pthread.h>
#include <sys/resource.h>  // getrlimit, setrlimit
#include <termios.h>  // tcgetattr, tcsetattr
#endif

namespace node {

using v8::Array;
using v8::ArrayBuffer;
using v8::BigUint64Array;
using v8::Context;
using v8::Float64Array;
using v8::Function;
using v8::FunctionCallbackInfo;
using v8::HeapStatistics;
using v8::Isolate;
using v8::Local;
using v8::Name;
using v8::NewStringType;
using v8::PropertyCallbackInfo;
using v8::String;
using v8::Uint32;
using v8::Uint32Array;
using v8::Value;

Mutex process_mutex;
Mutex environ_mutex;

// Microseconds in a second, as a float, used in CPUUsage() below
#define MICROS_PER_SEC 1e6
// used in Hrtime() below
#define NANOS_PER_SEC 1000000000

#ifdef _WIN32
/* MAX_PATH is in characters, not bytes. Make sure we have enough headroom. */
#define CHDIR_BUFSIZE (MAX_PATH * 4)
#else
#define CHDIR_BUFSIZE (PATH_MAX)
#endif

void Abort(const FunctionCallbackInfo<Value>& args) {
  Abort();
}

void Chdir(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);
  CHECK(env->is_main_thread());

  CHECK_EQ(args.Length(), 1);
  CHECK(args[0]->IsString());
  Utf8Value path(env->isolate(), args[0]);
  int err = uv_chdir(*path);
  if (err) {
    // Also include the original working directory, since that will usually
    // be helpful information when debugging a `chdir()` failure.
    char buf[CHDIR_BUFSIZE];
    size_t cwd_len = sizeof(buf);
    uv_cwd(buf, &cwd_len);
    return env->ThrowUVException(err, "chdir", nullptr, buf, *path);
  }
}

// CPUUsage use libuv's uv_getrusage() this-process resource usage accessor,
// to access ru_utime (user CPU time used) and ru_stime (system CPU time used),
// which are uv_timeval_t structs (long tv_sec, long tv_usec).
// Returns those values as Float64 microseconds in the elements of the array
// passed to the function.
void CPUUsage(const FunctionCallbackInfo<Value>& args) {
  uv_rusage_t rusage;

  // Call libuv to get the values we'll return.
  int err = uv_getrusage(&rusage);
  if (err) {
    // On error, return the strerror version of the error code.
    Local<String> errmsg = OneByteString(args.GetIsolate(), uv_strerror(err));
    return args.GetReturnValue().Set(errmsg);
  }

  // Get the double array pointer from the Float64Array argument.
  CHECK(args[0]->IsFloat64Array());
  Local<Float64Array> array = args[0].As<Float64Array>();
  CHECK_EQ(array->Length(), 2);
  Local<ArrayBuffer> ab = array->Buffer();
  double* fields = static_cast<double*>(ab->GetContents().Data());

  // Set the Float64Array elements to be user / system values in microseconds.
  fields[0] = MICROS_PER_SEC * rusage.ru_utime.tv_sec + rusage.ru_utime.tv_usec;
  fields[1] = MICROS_PER_SEC * rusage.ru_stime.tv_sec + rusage.ru_stime.tv_usec;
}

void Cwd(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);
  char buf[CHDIR_BUFSIZE];
  size_t cwd_len = sizeof(buf);
  int err = uv_cwd(buf, &cwd_len);
  if (err)
    return env->ThrowUVException(err, "uv_cwd");

  Local<String> cwd = String::NewFromUtf8(env->isolate(),
                                          buf,
                                          NewStringType::kNormal,
                                          cwd_len).ToLocalChecked();
  args.GetReturnValue().Set(cwd);
}


// Hrtime exposes libuv's uv_hrtime() high-resolution timer.

// This is the legacy version of hrtime before BigInt was introduced in
// JavaScript.
// The value returned by uv_hrtime() is a 64-bit int representing nanoseconds,
// so this function instead fills in an Uint32Array with 3 entries,
// to avoid any integer overflow possibility.
// The first two entries contain the second part of the value
// broken into the upper/lower 32 bits to be converted back in JS,
// because there is no Uint64Array in JS.
// The third entry contains the remaining nanosecond part of the value.
void Hrtime(const FunctionCallbackInfo<Value>& args) {
  uint64_t t = uv_hrtime();

  Local<ArrayBuffer> ab = args[0].As<Uint32Array>()->Buffer();
  uint32_t* fields = static_cast<uint32_t*>(ab->GetContents().Data());

  fields[0] = (t / NANOS_PER_SEC) >> 32;
  fields[1] = (t / NANOS_PER_SEC) & 0xffffffff;
  fields[2] = t % NANOS_PER_SEC;
}

void HrtimeBigInt(const FunctionCallbackInfo<Value>& args) {
  Local<ArrayBuffer> ab = args[0].As<BigUint64Array>()->Buffer();
  uint64_t* fields = static_cast<uint64_t*>(ab->GetContents().Data());
  fields[0] = uv_hrtime();
}

void Kill(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);
  Local<Context> context = env->context();

  if (args.Length() != 2)
    return env->ThrowError("Bad argument.");

  int pid;
  if (!args[0]->Int32Value(context).To(&pid)) return;
  int sig;
  if (!args[1]->Int32Value(context).To(&sig)) return;
  int err = uv_kill(pid, sig);
  args.GetReturnValue().Set(err);
}


void MemoryUsage(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);

  size_t rss;
  int err = uv_resident_set_memory(&rss);
  if (err)
    return env->ThrowUVException(err, "uv_resident_set_memory");

  Isolate* isolate = env->isolate();
  // V8 memory usage
  HeapStatistics v8_heap_stats;
  isolate->GetHeapStatistics(&v8_heap_stats);

  // Get the double array pointer from the Float64Array argument.
  CHECK(args[0]->IsFloat64Array());
  Local<Float64Array> array = args[0].As<Float64Array>();
  CHECK_EQ(array->Length(), 4);
  Local<ArrayBuffer> ab = array->Buffer();
  double* fields = static_cast<double*>(ab->GetContents().Data());

  fields[0] = rss;
  fields[1] = v8_heap_stats.total_heap_size();
  fields[2] = v8_heap_stats.used_heap_size();
  fields[3] = v8_heap_stats.external_memory();
}

// Most of the time, it's best to use `console.error` to write
// to the process.stderr stream.  However, in some cases, such as
// when debugging the stream.Writable class or the process.nextTick
// function, it is useful to bypass JavaScript entirely.
void RawDebug(const FunctionCallbackInfo<Value>& args) {
  CHECK(args.Length() == 1 && args[0]->IsString() &&
        "must be called with a single string");
  Utf8Value message(args.GetIsolate(), args[0]);
  PrintErrorString("%s\n", *message);
  fflush(stderr);
}

void StartProfilerIdleNotifier(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);
  env->StartProfilerIdleNotifier();
}


void StopProfilerIdleNotifier(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);
  env->StopProfilerIdleNotifier();
}

void Umask(const FunctionCallbackInfo<Value>& args) {
  uint32_t old;

  CHECK_EQ(args.Length(), 1);
  CHECK(args[0]->IsUndefined() || args[0]->IsUint32());

  if (args[0]->IsUndefined()) {
    old = umask(0);
    umask(static_cast<mode_t>(old));
  } else {
    int oct = args[0].As<Uint32>()->Value();
    old = umask(static_cast<mode_t>(oct));
  }

  args.GetReturnValue().Set(old);
}

void Uptime(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);
  double uptime;

  uv_update_time(env->event_loop());
  uptime = uv_now(env->event_loop()) - prog_start_time;

  args.GetReturnValue().Set(uptime / 1000);
}

void ProcessTitleGetter(Local<Name> property,
                        const PropertyCallbackInfo<Value>& info) {
  char buffer[512];
  uv_get_process_title(buffer, sizeof(buffer));
  info.GetReturnValue().Set(String::NewFromUtf8(info.GetIsolate(), buffer,
      NewStringType::kNormal).ToLocalChecked());
}


void ProcessTitleSetter(Local<Name> property,
                        Local<Value> value,
                        const PropertyCallbackInfo<void>& info) {
  node::Utf8Value title(info.GetIsolate(), value);
  TRACE_EVENT_METADATA1("__metadata", "process_name", "name",
                        TRACE_STR_COPY(*title));
  uv_set_process_title(*title);
}

void GetParentProcessId(Local<Name> property,
                        const PropertyCallbackInfo<Value>& info) {
  info.GetReturnValue().Set(uv_os_getppid());
}

void GetActiveRequests(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);

  std::vector<Local<Value>> request_v;
  for (auto w : *env->req_wrap_queue()) {
    if (w->persistent().IsEmpty())
      continue;
    request_v.push_back(w->GetOwner());
  }

  args.GetReturnValue().Set(
      Array::New(env->isolate(), request_v.data(), request_v.size()));
}

// Non-static, friend of HandleWrap. Could have been a HandleWrap method but
// implemented here for consistency with GetActiveRequests().
void GetActiveHandles(const FunctionCallbackInfo<Value>& args) {
  Environment* env = Environment::GetCurrent(args);

  std::vector<Local<Value>> handle_v;
  for (auto w : *env->handle_wrap_queue()) {
    if (!HandleWrap::HasRef(w))
      continue;
    handle_v.push_back(w->GetOwner());
  }
  args.GetReturnValue().Set(
      Array::New(env->isolate(), handle_v.data(), handle_v.size()));
}

void DebugPortGetter(Local<Name> property,
                     const PropertyCallbackInfo<Value>& info) {
  Environment* env = Environment::GetCurrent(info);
  int port = env->inspector_host_port()->port();
  info.GetReturnValue().Set(port);
}


void DebugPortSetter(Local<Name> property,
                     Local<Value> value,
                     const PropertyCallbackInfo<void>& info) {
  Environment* env = Environment::GetCurrent(info);
  int32_t port = value->Int32Value(env->context()).FromMaybe(0);
  env->inspector_host_port()->set_port(static_cast<int>(port));
}


}  // namespace node