// Copyright (c) 2012 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 CHROME_BROWSER_PASSWORD_MANAGER_PASSWORD_MANAGER_H_
#define CHROME_BROWSER_PASSWORD_MANAGER_PASSWORD_MANAGER_H_

#include <vector>

#include "base/callback.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/scoped_vector.h"
#include "base/observer_list.h"
#include "base/prefs/pref_member.h"
#include "base/stl_util.h"
#include "chrome/browser/password_manager/password_form_manager.h"
#include "chrome/browser/ui/login/login_model.h"
#include "components/autofill/core/common/password_form.h"
#include "components/autofill/core/common/password_form_fill_data.h"
#include "content/public/browser/web_contents_observer.h"
#include "content/public/browser/web_contents_user_data.h"

class PasswordManagerDelegate;
class PasswordManagerTest;
class PasswordFormManager;
class PrefRegistrySimple;

namespace user_prefs {
class PrefRegistrySyncable;
}

// Per-tab password manager. Handles creation and management of UI elements,
// receiving password form data from the renderer and managing the password
// database through the PasswordStore. The PasswordManager is a LoginModel
// for purposes of supporting HTTP authentication dialogs.
class PasswordManager : public LoginModel,
                        public content::WebContentsObserver,
                        public content::WebContentsUserData<PasswordManager> {
 public:
  static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
#if defined(OS_WIN)
  static void RegisterLocalPrefs(PrefRegistrySimple* registry);
#endif
  static void CreateForWebContentsAndDelegate(
      content::WebContents* contents,
      PasswordManagerDelegate* delegate);
  virtual ~PasswordManager();

  typedef base::Callback<void(const autofill::PasswordForm&)>
      PasswordSubmittedCallback;

  // There is no corresponding remove function as currently all of the
  // owners of these callbacks have sufficient lifetimes so that the callbacks
  // should always be valid when called.
  void AddSubmissionCallback(const PasswordSubmittedCallback& callback);

  // Is saving new data for password autofill enabled for the current profile?
  // For example, saving new data is disabled in Incognito mode, whereas filling
  // data is not.
  bool IsSavingEnabled() const;

  // Called by a PasswordFormManager when it decides a form can be autofilled
  // on the page.
  virtual void Autofill(const autofill::PasswordForm& form_for_autofill,
                        const autofill::PasswordFormMap& best_matches,
                        const autofill::PasswordForm& preferred_match,
                        bool wait_for_username) const;

  // LoginModel implementation.
  virtual void AddObserver(LoginModelObserver* observer) OVERRIDE;
  virtual void RemoveObserver(LoginModelObserver* observer) OVERRIDE;

  // Mark this form as having a generated password.
  void SetFormHasGeneratedPassword(const autofill::PasswordForm& form);

  // TODO(isherman): This should not be public, but is currently being used by
  // the LoginPrompt code.
  // When a form is submitted, we prepare to save the password but wait
  // until we decide the user has successfully logged in. This is step 1
  // of 2 (see SavePassword).
  void ProvisionallySavePassword(const autofill::PasswordForm& form);

  // content::WebContentsObserver overrides.
  virtual void DidNavigateMainFrame(
      const content::LoadCommittedDetails& details,
      const content::FrameNavigateParams& params) OVERRIDE;
  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;

  // TODO(isherman): This should not be public, but is currently being used by
  // the LoginPrompt code.
  void OnPasswordFormsParsed(
      const std::vector<autofill::PasswordForm>& forms);
  void OnPasswordFormsRendered(
      const std::vector<autofill::PasswordForm>& visible_forms);

 protected:
  // Subclassed for unit tests.
  PasswordManager(content::WebContents* web_contents,
                  PasswordManagerDelegate* delegate);

  // Handle notification that a password form was submitted.
  virtual void OnPasswordFormSubmitted(
      const autofill::PasswordForm& password_form);

 private:
  friend class content::WebContentsUserData<PasswordManager>;

  enum ProvisionalSaveFailure {
    SAVING_DISABLED,
    EMPTY_PASSWORD,
    NO_MATCHING_FORM,
    MATCHING_NOT_COMPLETE,
    FORM_BLACKLISTED,
    INVALID_FORM,
    AUTOCOMPLETE_OFF,
    MAX_FAILURE_VALUE
  };

  // Log failure for UMA. Logs additional metrics if the |form_origin|
  // corresponds to one of the top, explicitly monitored websites.
  void RecordFailure(ProvisionalSaveFailure failure,
                     const std::string& form_origin);

  // Possibly set up FieldTrial for testing other possible usernames. This only
  // happens if there are other_possible_usernames to be shown and the
  // experiment hasn't already been initialized. We setup the experiment at
  // such a late time because this experiment will only affect a small number
  // of users so we want to include a larger fraction of these users than the
  // normal 10%.
  void PossiblyInitializeUsernamesExperiment(
      const autofill::PasswordFormMap& matches) const;

  // Returns true if we can show possible usernames to users in cases where
  // the username for the form is ambigious.
  bool OtherPossibleUsernamesEnabled() const;

  // Returns true if we should show an infobar instead of automatically saving
  // the password, based on inspecting the state of |provisional_save_manager_|.
  bool ShouldShowSavePasswordInfoBar() const;

  // Note about how a PasswordFormManager can transition from
  // pending_login_managers_ to provisional_save_manager_ and the infobar.
  //
  // 1. form "seen"
  //       |                                             new
  //       |                                               ___ Infobar
  // pending_login -- form submit --> provisional_save ___/
  //             ^                            |           \___ (update DB)
  //             |                           fail
  //             |-----------<------<---------|          !new
  //
  // When a form is "seen" on a page, a PasswordFormManager is created
  // and stored in this collection until user navigates away from page.

  ScopedVector<PasswordFormManager> pending_login_managers_;

  // When the user submits a password/credential, this contains the
  // PasswordFormManager for the form in question until we deem the login
  // attempt to have succeeded (as in valid credentials). If it fails, we
  // send the PasswordFormManager back to the pending_login_managers_ set.
  // Scoped in case PasswordManager gets deleted (e.g tab closes) between the
  // time a user submits a login form and gets to the next page.
  scoped_ptr<PasswordFormManager> provisional_save_manager_;

  // Our delegate for carrying out external operations.  This is typically the
  // containing WebContents.
  PasswordManagerDelegate* const delegate_;

  // Set to false to disable the password manager (will no longer ask if you
  // want to save passwords but will continue to fill passwords).
  BooleanPrefMember password_manager_enabled_;

  // Observers to be notified of LoginModel events.  This is mutable to allow
  // notification in const member functions.
  mutable ObserverList<LoginModelObserver> observers_;

  // Callbacks to be notified when a password form has been submitted.
  std::vector<PasswordSubmittedCallback> submission_callbacks_;

  DISALLOW_COPY_AND_ASSIGN(PasswordManager);
};

#endif  // CHROME_BROWSER_PASSWORD_MANAGER_PASSWORD_MANAGER_H_