Added the AutomaticProfileResetter service.

chrome/browser/profile_resetter/automatic_profile_resetter.h

+// Copyright 2013 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_PROFILE_RESETTER_AUTOMATIC_PROFILE_RESETTER_H_
+#define CHROME_BROWSER_PROFILE_RESETTER_AUTOMATIC_PROFILE_RESETTER_H_
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "base/strings/string_piece.h"
+#include "base/values.h"
+#include "chrome/browser/profile_resetter/automatic_profile_resetter_mementos.h"
+#include "components/browser_context_keyed_service/browser_context_keyed_service.h"
+
+class Profile;
+
+// Defines the interface for the delegate that will actually show the prompt
+// and/or report statistics on behalf of the AutomaticProfileResetter.
+// The primary reason for this separation is to facilitate unit testing.
+class AutomaticProfileResetterDelegate {
+ public:
+  virtual ~AutomaticProfileResetterDelegate() {}
+
+  // Triggers showing the one-time profile settings reset prompt.
+  virtual void ShowPrompt() = 0;
+
+  // Reports the given metrics through UMA.
+  virtual void ReportStatistics(uint32 satisfied_criteria_mask,
+                                uint32 combined_status_mask) = 0;
+};
+
+// This service becomes busy shortly after start-up, and is responsible for
+// evaluating if the criteria for showing the one-time profile reset prompt
+// are satisfied, and potentially triggering the prompt, but only a single time
+// during the lifetime of a profile on disk (this is achieved by storing
+// "mementos"). All methods in this class shall be called on the UI thread.
+class AutomaticProfileResetter : public BrowserContextKeyedService {
+ public:
+  explicit AutomaticProfileResetter(Profile* profile);
+  virtual ~AutomaticProfileResetter();
+
+  // Initializes the service, and sets up the asynchronous evaluation flow.
+  // Called by AutomaticProfileResetterFactory.
+  void Initialize();
+
+  // Should be called after Initialize().
+  void SetHashSeedForTesting(const base::StringPiece& hash_seed);
+
+  // Should be called after Initialize().
+  void SetProgramForTesting(const base::StringPiece& program);
+
+  // Should be called after Initialize(). Takes ownership.
+  void SetDelegateForTesting(AutomaticProfileResetterDelegate* delegate);
+
+ private:
+  struct EvaluationResults;
+
+  enum State {
+    STATE_UNINITIALIZED,
+    STATE_DISABLED,
+    STATE_READY,
+    STATE_WORKING,
+    STATE_DONE
+  };
+
+  // Returns whether or not a dry-run shall be performed.
+  bool ShouldPerformDryRun() const;
+
+  // Returns whether or not a live-run shall be performed.
+  bool ShouldPerformLiveRun() const;
+
+  // Begins the asynchronous evaluation flow, which will assess whether the
+  // criteria for showing the reset prompt are met, whether we have already
+  // shown the prompt, and, in the end, will potentially trigger the prompt.
+  void BeginEvaluationFlow();
+
+  // Called back by |memento_in_file_| once it has finished reading the value of
+  // the file-based memento. Continues the evaluation flow with collecting state
+  // information and assembling it as the input for the evaluator program.
+  void ContinueWithEvaluationFlow(const std::string& memento_value_in_file);
+
+  // Prepare the input of the evaluator program that will contain all the state
+  // information required to assess whether the conditions for showing the reset
+  // prompt are met.
+  scoped_ptr<base::DictionaryValue> BuildEvaluatorProgramInput(
+      const std::string& memento_value_in_file);
+
+  // Performs the bulk of the work. Invokes the interpreter to run the |program|
+  // that will evaluate whether the conditions for showing the reset prompt are
+  // satisfied. The program will make this decision based on state information
+  // contained in |input| in the form of key-value pairs that which will be
+  // hashed using |hash_key| as a key.
+  static scoped_ptr<EvaluationResults> EvaluateConditionsOnWorkerPoolThread(
+      const base::StringPiece& hash_key,
+      const base::StringPiece& program,
+      scoped_ptr<base::DictionaryValue> program_input);
+
+  // Called back when EvaluateConditionsOnWorkerPoolThread completes executing
+  // the program with |results|. Finishes the evaluation flow, and, based on the
+  // result, will potentially show the reset prompt.
+  void FinishEvaluationFlow(scoped_ptr<EvaluationResults> results);
+
+  // BrowserContextKeyedService overrides:
+  virtual void Shutdown() OVERRIDE;
+
+  Profile* profile_;
+
+  State state_;
+
+  base::StringPiece hash_seed_;
+  base::StringPiece program_;
+
+  PreferenceHostedPromptMemento memento_in_prefs_;
+  LocalStateHostedPromptMemento memento_in_local_state_;
+  FileHostedPromptMemento memento_in_file_;
+
+  scoped_ptr<AutomaticProfileResetterDelegate> delegate_;
+
+  base::WeakPtrFactory<AutomaticProfileResetter> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(AutomaticProfileResetter);
+};
+
+#endif  // CHROME_BROWSER_PROFILE_RESETTER_AUTOMATIC_PROFILE_RESETTER_H_