// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_TRANSLATE_IOS_BROWSER_TRANSLATE_CONTROLLER_H_
#define COMPONENTS_TRANSLATE_IOS_BROWSER_TRANSLATE_CONTROLLER_H_

#include <string>

#include "base/gtest_prod_util.h"
#include "base/mac/scoped_nsobject.h"
#include "base/macros.h"
#include "base/memory/weak_ptr.h"
#include "ios/web/public/web_state/web_state_observer.h"

@class JsTranslateManager;
class GURL;

namespace base {
class DictionaryValue;
}

namespace web {
class WebState;
}

namespace translate {

// TranslateController controls the translation of the page, by injecting the
// translate scripts and monitoring the status.
class TranslateController : public web::WebStateObserver {
 public:
  // Observer class to monitor the progress of the translation.
  class Observer {
   public:
    // Called when the translate script is ready.
    // In case of timeout, |success| is false.
    virtual void OnTranslateScriptReady(bool success,
                                        double load_time,
                                        double ready_time) = 0;

    // Called when the translation is complete.
    virtual void OnTranslateComplete(bool success,
                                     const std::string& original_language,
                                     double translation_time) = 0;
  };

  TranslateController(web::WebState* web_state, JsTranslateManager* manager);
  ~TranslateController() override;

  // Sets the observer.
  void set_observer(Observer* observer) { observer_ = observer; }

  // Injects the translate script.
  void InjectTranslateScript(const std::string& translate_script);

  // Reverts the translation.
  void RevertTranslation();

  // Starts the translation. Must be called when the translation script is
  // ready.
  void StartTranslation(const std::string& source_language,
                        const std::string& target_language);

  // Checks the translation status and calls the observer when it is done.
  // This method must be called after StartTranslation().
  void CheckTranslateStatus();

  // Changes the JsTranslateManager used by this TranslateController.
  // Only used for testing.
  void SetJsTranslateManagerForTesting(JsTranslateManager* manager) {
    js_manager_.reset([manager retain]);
  }

 private:
  FRIEND_TEST_ALL_PREFIXES(TranslateControllerTest,
                           OnJavascriptCommandReceived);
  FRIEND_TEST_ALL_PREFIXES(TranslateControllerTest,
                           OnTranslateScriptReadyTimeoutCalled);
  FRIEND_TEST_ALL_PREFIXES(TranslateControllerTest,
                           OnTranslateScriptReadyCalled);
  FRIEND_TEST_ALL_PREFIXES(TranslateControllerTest, TranslationSuccess);
  FRIEND_TEST_ALL_PREFIXES(TranslateControllerTest, TranslationFailure);

  // Called when a JavaScript command is received.
  bool OnJavascriptCommandReceived(const base::DictionaryValue& command,
                                   const GURL& url,
                                   bool interacting);
  // Methods to handle specific JavaScript commands.
  // Return false if the command is invalid.
  bool OnTranslateReady(const base::DictionaryValue& command);
  bool OnTranslateComplete(const base::DictionaryValue& command);

  // web::WebStateObserver implementation:
  void WebStateDestroyed() override;

  Observer* observer_;
  base::scoped_nsobject<JsTranslateManager> js_manager_;
  base::WeakPtrFactory<TranslateController> weak_method_factory_;

  DISALLOW_COPY_AND_ASSIGN(TranslateController);
};

}  // namespace translate

#endif  // COMPONENTS_TRANSLATE_IOS_BROWSER_TRANSLATE_CONTROLLER_H_