////////////////////////////////////////////////////////////////////////////////
/// @brief console thread
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2014 ArangoDB GmbH, Cologne, Germany
/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
///     http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Jan Steemann
/// @author Copyright 2014, ArangoDB GmbH, Cologne, Germany
/// @author Copyright 2009-2013, triAGENS GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////

#include <iostream>

#include "ConsoleThread.h"

#include "ApplicationServer/ApplicationServer.h"
#include "Basics/logging.h"
#include "Basics/tri-strings.h"
#include "Basics/MutexLocker.h"
#include "Rest/Version.h"
#include "VocBase/vocbase.h"
#include "V8/V8LineEditor.h"
#include "V8/v8-conv.h"
#include "V8/v8-utils.h"
#include <v8.h>

using namespace triagens::basics;
using namespace triagens::rest;
using namespace triagens::arango;
using namespace arangodb;
using namespace std;

std::atomic<V8LineEditor*> triagens::arango::serverConsole(nullptr);
triagens::basics::Mutex triagens::arango::serverConsoleMutex;

// -----------------------------------------------------------------------------
// --SECTION--                                               class ConsoleThread
// -----------------------------------------------------------------------------

// -----------------------------------------------------------------------------
// --SECTION--                                      constructors and destructors
// -----------------------------------------------------------------------------

////////////////////////////////////////////////////////////////////////////////
/// @brief constructs a console thread
////////////////////////////////////////////////////////////////////////////////

ConsoleThread::ConsoleThread (ApplicationServer* applicationServer,
                              ApplicationV8* applicationV8,
                              TRI_vocbase_t* vocbase)
  : Thread("console"),
    _applicationServer(applicationServer),
    _applicationV8(applicationV8),
    _context(nullptr),
    _vocbase(vocbase),
    _done(0),
    _userAborted(false) {

  allowAsynchronousCancelation();
}

////////////////////////////////////////////////////////////////////////////////
/// @brief destroys a console thread
////////////////////////////////////////////////////////////////////////////////

ConsoleThread::~ConsoleThread () {
}

// -----------------------------------------------------------------------------
// --SECTION--                                                    public methods
// -----------------------------------------------------------------------------

////////////////////////////////////////////////////////////////////////////////
/// @brief runs the thread
////////////////////////////////////////////////////////////////////////////////

void ConsoleThread::run () {
  usleep(100000);

  // enter V8 context
  _context = _applicationV8->enterContext(_vocbase, true);

  try {
    inner();
  }
  catch (const char*) {
  }
  catch (...) {
    _applicationV8->exitContext(_context);
    _done = 1;
    _applicationServer->beginShutdown();

    throw;
  }

  _applicationV8->exitContext(_context);
  _done = 1;
  _applicationServer->beginShutdown();
}

// -----------------------------------------------------------------------------
// --SECTION--                                                   private methods
// -----------------------------------------------------------------------------

////////////////////////////////////////////////////////////////////////////////
/// @brief inner thread loop - this handles all the user inputs
////////////////////////////////////////////////////////////////////////////////

void ConsoleThread::inner () {
  v8::Isolate* isolate = _context->isolate;
  v8::HandleScope globalScope(isolate);

  // run the shell
  std::cout << "ArangoDB JavaScript emergency console (" << rest::Version::getVerboseVersionString() << ")" << std::endl;

  v8::Local<v8::String> name(TRI_V8_ASCII_STRING(TRI_V8_SHELL_COMMAND_NAME));

  auto localContext = v8::Local<v8::Context>::New(isolate, _context->_context);
  localContext->Enter();
  {
    v8::Context::Scope contextScope(localContext);

    // .............................................................................
    // run console
    // .............................................................................

    const uint64_t gcInterval = 10;
    uint64_t nrCommands = 0;

    // read and eval .arangod.rc from home directory if it exists
    char const* startupScript = R"SCRIPT(
start_pretty_print();

(function () {
  var __fs__ = require("fs"); 
  var __rcf__ = __fs__.join(__fs__.home(), ".arangod.rc"); 
  if (__fs__.exists(__rcf__)) { 
    try { 
      var __content__ = __fs__.read(__rcf__); 
      eval(__content__); 
    } 
    catch (err) {
      require("console").log("error in rc file '%s': %s", __rcf__, String(err.stack || err)); 
    } 
  }
})();
)SCRIPT";

    TRI_ExecuteJavaScriptString(isolate,
                                localContext,
                                TRI_V8_ASCII_STRING(startupScript),
                                TRI_V8_ASCII_STRING("(startup)"),
                                false);

    V8LineEditor console(localContext, ".arangod.history");

    console.open(true);

    serverConsole = &console;

    while (! _userAborted) {
      if (nrCommands >= gcInterval) {
        TRI_RunGarbageCollectionV8(isolate, 0.5);
        nrCommands = 0;
      }

      string input;
      bool eof;
      {
        MUTEX_LOCKER(serverConsoleMutex);
        input = console.prompt("arangod> ", "arangod", eof);
      }

      if (eof) {
        _userAborted = true;
      }

      if (_userAborted) {
        break;
      }

      if (input.empty()) {
        continue;
      }

      nrCommands++;
      console.addHistory(input);

      {
        v8::TryCatch tryCatch;
        v8::HandleScope scope(isolate);

        TRI_ExecuteJavaScriptString(isolate, localContext, TRI_V8_STRING(input.c_str()), name, true);

        if (tryCatch.HasCaught()) {
          std::cout << TRI_StringifyV8Exception(isolate, &tryCatch);
        }
      }
    }

    {
      MUTEX_LOCKER(serverConsoleMutex);
      serverConsole = nullptr;
    }

  }
  localContext->Exit();
  throw "user aborted";
}

// -----------------------------------------------------------------------------
// --SECTION--                                                       END-OF-FILE
// -----------------------------------------------------------------------------

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