[CUPS] Implement the Print Job notification.

chrome/browser/chromeos/printing/cups_print_job_manager.h

+// Copyright 2016 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_CHROMEOS_PRINTING_CUPS_PRINT_JOB_MANAGER_H_
+#define CHROME_BROWSER_CHROMEOS_PRINTING_CUPS_PRINT_JOB_MANAGER_H_
+
+#include <vector>
+
+#include "chrome/browser/chromeos/printing/cups_print_job.h"
+#include "components/keyed_service/core/keyed_service.h"
+
+class Profile;
+
+namespace content {
+class BrowserContext;
+}
+
+namespace chromeos {
+
+class CupsPrintJobNotificationManager;
+
+class CupsPrintJobManager : public KeyedService {
+ public:
+  class Observer {
+   public:
+    virtual void OnPrintJobCreated(CupsPrintJob* job) {}
+    virtual void OnPrintJobStarted(CupsPrintJob* job) {}
+    virtual void OnPrintJobUpdated(CupsPrintJob* job) {}
+    virtual void OnPrintJobSuspended(CupsPrintJob* job) {}
+    virtual void OnPrintJobResumed(CupsPrintJob* job) {}
+    virtual void OnPrintJobDone(CupsPrintJob* job) {}
+    virtual void OnPrintJobError(CupsPrintJob* job) {}
+    virtual void OnPrintJobCancelled(int job_id) {}
+
+   protected:
+    virtual ~Observer() {}
+  };
+
+  using PrintJobs = std::vector<std::unique_ptr<CupsPrintJob>>;
+
+  explicit CupsPrintJobManager(Profile* profile);
+  ~CupsPrintJobManager() override;
+
+  // KeyedService override:
+  void Shutdown() override;
+
+  // Returns the CupsPrintJobManager instance that associated with the current
+  // profile.
+  static CupsPrintJobManager* Get(content::BrowserContext* browser_context);
+
+  virtual bool CreatePrintJob(const std::string& printer_name,
+                              const std::string& title,
+                              int total_page_number) = 0;
+  virtual bool CancelPrintJob(CupsPrintJob* job) = 0;

[skau, 2016/10/27 01:43:00]

Should we change this to CupsPrintJob#UniqueId?

[xdai1, 2016/10/28 23:59:53]

Why? Actually since |job| is owned by CupsPrintJobManager, it should be deleted
in the function CancelPrintJob().

[skau, 2016/10/31 15:39:05]

It's not obvious that this method will delete the object that's passed into it. 
You should add the note to the observer that the corresponding print job will be
deleted after cancelled is called so nobody tries to de-reference it.

+  virtual bool SuspendPrintJob(CupsPrintJob* job) = 0;
+  virtual bool ResumePrintJob(CupsPrintJob* job) = 0;
+
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+ protected:
+  PrintJobs print_jobs_;
+  Profile* profile_;
+  std::unique_ptr<CupsPrintJobNotificationManager> notification_manager_;
+  std::vector<Observer*> observers_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(CupsPrintJobManager);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_PRINTING_CUPS_PRINT_JOB_MANAGER_H_