// Copyright 2008, Google Inc.
//
// Redistribution and use in source and binary forms, with or without 
// modification, are permitted provided that the following conditions are met:
//
//  1. Redistributions of source code must retain the above copyright notice, 
//     this list of conditions and the following disclaimer.
//  2. Redistributions in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
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//     used to endorse or promote products derived from this software without
//     specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
// WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
// EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
// OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
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#include "gears/console/js_callback_logging_backend.h"

#include "gears/base/common/scoped_refptr.h"
#include "gears/console/console.h"


JsCallbackLoggingBackend::JsCallbackLoggingBackend(const std::string16 &topic,
                                                   JsRunnerInterface* js_runner,
                                                   GearsConsole *console)
    : observer_topic_(topic), js_runner_(js_runner), console_(console) {
  LogEvent::RegisterLogEventClass();
}

JsCallbackLoggingBackend::~JsCallbackLoggingBackend() {
  ClearCallback();
}

void JsCallbackLoggingBackend::OnNotify(MessageService *service,
                            const char16 *topic,
                            const NotificationData *data) {
  if (!callback_.get() || js_runner_ == NULL) return;

  // Keep a ref to the console.  Otherwise, the calls to js_runner may result in
  // its release, which deletes us.
  scoped_refptr<GearsConsole> hold(console_);

  const LogEvent *log_event = static_cast<const LogEvent *>(data);
  
  scoped_ptr<JsObject> callback_params;
  callback_params.reset(js_runner_->NewObject());
  if (!callback_params.get()) return;

  callback_params.get()->SetPropertyString(STRING16(L"message"),
                                           log_event->message().c_str());
  callback_params.get()->SetPropertyString(STRING16(L"type"),
                                           log_event->type().c_str());
  callback_params.get()->SetPropertyString(STRING16(L"sourceUrl"),
                                           log_event->sourceUrl().c_str());
  scoped_ptr<JsObject> date(js_runner_->NewDate(log_event->date()));
  if (date.get()) {
    callback_params.get()->SetPropertyObject(STRING16(L"date"),
                                             date.get());
  }
  
  const int argc = 1;
  JsParamToSend argv[argc] = {
    { JSPARAM_OBJECT, callback_params.get() },
  };
  js_runner_->InvokeCallback(callback_.get(), argc, argv, NULL);
}

JsRootedCallback *JsCallbackLoggingBackend::GetCallback() {
  return callback_.get();
}

void JsCallbackLoggingBackend::SetCallback(JsRootedCallback* callback) {
  if (!callback) {
    ClearCallback();
    return;
  }
  // If callback has not been set yet, we need to attach ourself as an
  // observer to log stream
  if (!callback_.get()) {
    callback_.reset(callback);
    MessageService::GetInstance()->AddObserver(this,
                                               observer_topic_.c_str());
  } else {
    callback_.reset(callback);
  }
}

void JsCallbackLoggingBackend::ClearCallback() {
  // If a callback is set, we need to remove ourself as an observer from the
  // log stream
  if (callback_.get()) {
    MessageService::GetInstance()->RemoveObserver(this,
                                                  observer_topic_.c_str());
  }
  callback_.reset(NULL);
}