// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

#include "node.h"
#include "handle_wrap.h"
#include "pipe_wrap.h"
#include <string.h>
#include <stdlib.h>

namespace node {

using v8::Object;
using v8::Handle;
using v8::Local;
using v8::Persistent;
using v8::Value;
using v8::HandleScope;
using v8::FunctionTemplate;
using v8::String;
using v8::Array;
using v8::Function;
using v8::TryCatch;
using v8::Context;
using v8::Arguments;
using v8::Integer;
using v8::Exception;
using v8::ThrowException;

static Persistent<String> onexit_sym;

class ProcessWrap : public HandleWrap {
 public:
  static void Initialize(Handle<Object> target) {
    HandleScope scope;

    HandleWrap::Initialize(target);

    Local<FunctionTemplate> constructor = FunctionTemplate::New(New);
    constructor->InstanceTemplate()->SetInternalFieldCount(1);
    constructor->SetClassName(String::NewSymbol("Process"));

    NODE_SET_PROTOTYPE_METHOD(constructor, "close", HandleWrap::Close);

    NODE_SET_PROTOTYPE_METHOD(constructor, "spawn", Spawn);
    NODE_SET_PROTOTYPE_METHOD(constructor, "kill", Kill);

    target->Set(String::NewSymbol("Process"), constructor->GetFunction());
  }

 private:
  static Handle<Value> New(const Arguments& args) {
    // This constructor should not be exposed to public javascript.
    // Therefore we assert that we are not trying to call this as a
    // normal function.
    assert(args.IsConstructCall());

    HandleScope scope;
    ProcessWrap *wrap = new ProcessWrap(args.This());
    assert(wrap);

    return scope.Close(args.This());
  }

  ProcessWrap(Handle<Object> object) : HandleWrap(object, NULL) { }
  ~ProcessWrap() { }

  static Handle<Value> Spawn(const Arguments& args) {
    HandleScope scope;

    UNWRAP(ProcessWrap)

    Local<Object> js_options = args[0]->ToObject();

    uv_process_options_t options;
    memset(&options, 0, sizeof(uv_process_options_t));

    options.exit_cb = OnExit;

    // options.uid
    Local<Value> uid_v = js_options->Get(String::NewSymbol("uid"));
    if (uid_v->IsInt32()) {
      int32_t uid = uid_v->Int32Value();
      if (uid & ~((uv_uid_t) ~0)) {
        return ThrowException(Exception::RangeError(
            String::New("options.uid is out of range")));
      }
      options.flags |= UV_PROCESS_SETUID;
      options.uid = (uv_uid_t) uid;
    } else if (!uid_v->IsUndefined() && !uid_v->IsNull()) {
      return ThrowException(Exception::TypeError(
          String::New("options.uid should be a number")));
    }

    // options.gid
    Local<Value> gid_v = js_options->Get(String::NewSymbol("gid"));
    if (gid_v->IsInt32()) {
      int32_t gid = gid_v->Int32Value();
      if (gid & ~((uv_gid_t) ~0)) {
        return ThrowException(Exception::RangeError(
           String::New("options.gid is out of range")));
      }
      options.flags |= UV_PROCESS_SETGID;
      options.gid = (uv_gid_t) gid;
    } else if (!gid_v->IsUndefined() && !gid_v->IsNull()) {
      return ThrowException(Exception::TypeError(
          String::New("options.gid should be a number")));
    }

    // TODO is this possible to do without mallocing ?

    // options.file
    Local<Value> file_v = js_options->Get(String::NewSymbol("file"));
    String::Utf8Value file(file_v->IsString() ? file_v : Local<Value>());
    if (file.length() > 0) {
      options.file = *file;
    } else {
      return ThrowException(Exception::TypeError(String::New("Bad argument")));
    }

    // options.args
    Local<Value> argv_v = js_options->Get(String::NewSymbol("args"));
    if (!argv_v.IsEmpty() && argv_v->IsArray()) {
      Local<Array> js_argv = Local<Array>::Cast(argv_v);
      int argc = js_argv->Length();
      // Heap allocate to detect errors. +1 is for NULL.
      options.args = new char*[argc + 1];
      for (int i = 0; i < argc; i++) {
        String::Utf8Value arg(js_argv->Get(i));
        options.args[i] = strdup(*arg);
      }
      options.args[argc] = NULL;
    }

    // options.cwd
    Local<Value> cwd_v = js_options->Get(String::NewSymbol("cwd"));
    String::Utf8Value cwd(cwd_v->IsString() ? cwd_v : Local<Value>());
    if (cwd.length() > 0) {
      options.cwd = *cwd;
    }

    // options.env
    Local<Value> env_v = js_options->Get(String::NewSymbol("envPairs"));
    if (!env_v.IsEmpty() && env_v->IsArray()) {
      Local<Array> env = Local<Array>::Cast(env_v);
      int envc = env->Length();
      options.env = new char*[envc + 1]; // Heap allocated to detect errors.
      for (int i = 0; i < envc; i++) {
        String::Utf8Value pair(env->Get(i));
        options.env[i] = strdup(*pair);
      }
      options.env[envc] = NULL;
    }

    uv_stdio_container_t stdio[3];
    memset(stdio, 0, sizeof(stdio));

    options.stdio = stdio;
    options.stdio_count = 3;
    options.stdio[0].flags = UV_IGNORE;
    options.stdio[1].flags = UV_IGNORE;
    options.stdio[2].flags = UV_IGNORE;

    // options.stdin_stream
    Local<Value> stdin_stream_v = js_options->Get(
        String::NewSymbol("stdinStream"));
    if (!stdin_stream_v.IsEmpty() && stdin_stream_v->IsObject()) {
      PipeWrap* stdin_wrap = PipeWrap::Unwrap(stdin_stream_v->ToObject());
      options.stdio[0].flags = static_cast<uv_stdio_flags>(
          UV_CREATE_PIPE | UV_WRITABLE_PIPE);
      options.stdio[0].data.stream = reinterpret_cast<uv_stream_t*>(
          stdin_wrap->UVHandle());
    }

    // options.stdout_stream
    Local<Value> stdout_stream_v = js_options->Get(
        String::NewSymbol("stdoutStream"));
    if (!stdout_stream_v.IsEmpty() && stdout_stream_v->IsObject()) {
      PipeWrap* stdout_wrap = PipeWrap::Unwrap(stdout_stream_v->ToObject());
      options.stdio[1].flags = static_cast<uv_stdio_flags>(
          UV_CREATE_PIPE | UV_READABLE_PIPE);
      options.stdio[1].data.stream = reinterpret_cast<uv_stream_t*>(
          stdout_wrap->UVHandle());
    }

    // options.stderr_stream
    Local<Value> stderr_stream_v = js_options->Get(
        String::NewSymbol("stderrStream"));
    if (!stderr_stream_v.IsEmpty() && stderr_stream_v->IsObject()) {
      PipeWrap* stderr_wrap = PipeWrap::Unwrap(stderr_stream_v->ToObject());
      options.stdio[2].flags = static_cast<uv_stdio_flags>(
          UV_CREATE_PIPE | UV_READABLE_PIPE);
      options.stdio[2].data.stream = reinterpret_cast<uv_stream_t*>(
          stderr_wrap->UVHandle());
    }

    // options.windows_verbatim_arguments
    if (js_options->Get(String::NewSymbol("windowsVerbatimArguments"))->
          IsTrue()) {
      options.flags |= UV_PROCESS_WINDOWS_VERBATIM_ARGUMENTS;
    }

    int r = uv_spawn(uv_default_loop(), &wrap->process_, options);

    if (r) {
      SetErrno(uv_last_error(uv_default_loop()));
    }
    else {
      wrap->SetHandle((uv_handle_t*)&wrap->process_);
      assert(wrap->process_.data == wrap);
      wrap->object_->Set(String::New("pid"), Integer::New(wrap->process_.pid));
    }

    if (options.args) {
      for (int i = 0; options.args[i]; i++) free(options.args[i]);
      delete [] options.args;
    }

    if (options.env) {
      for (int i = 0; options.env[i]; i++) free(options.env[i]);
      delete [] options.env;
    }

    return scope.Close(Integer::New(r));
  }

  static Handle<Value> Kill(const Arguments& args) {
    HandleScope scope;

    UNWRAP(ProcessWrap)

    int signal = args[0]->Int32Value();

    int r = uv_process_kill(&wrap->process_, signal);

    if (r) SetErrno(uv_last_error(uv_default_loop()));

    return scope.Close(Integer::New(r));
  }

  static void OnExit(uv_process_t* handle, int exit_status, int term_signal) {
    HandleScope scope;

    ProcessWrap* wrap = static_cast<ProcessWrap*>(handle->data);
    assert(wrap);
    assert(&wrap->process_ == handle);

    Local<Value> argv[2] = {
      Integer::New(exit_status),
      String::New(signo_string(term_signal))
    };

    if (onexit_sym.IsEmpty()) {
      onexit_sym = NODE_PSYMBOL("onexit");
    }
    MakeCallback(wrap->object_, onexit_sym, ARRAY_SIZE(argv), argv);
  }

  uv_process_t process_;
};


}  // namespace node

NODE_MODULE(node_process_wrap, node::ProcessWrap::Initialize)