// 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_FEEDBACK_FEEDBACK_UPLOADER_H_
#define CHROME_BROWSER_FEEDBACK_FEEDBACK_UPLOADER_H_

#include <queue>
#include <string>

#include "base/basictypes.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/weak_ptr.h"
#include "base/time/time.h"
#include "base/timer/timer.h"
#include "chrome/browser/feedback/feedback_uploader_delegate.h"
#include "components/browser_context_keyed_service/browser_context_keyed_service.h"

namespace content {
class BrowserContext;
}

namespace feedback {

struct FeedbackReport;

// FeedbackUploader is used to add a feedback report to the queue of reports
// being uploaded. In case uploading a report fails, it is written to disk and
// tried again when it's turn comes up next in the queue.
class FeedbackUploader : public BrowserContextKeyedService,
                         public base::SupportsWeakPtr<FeedbackUploader> {
 public:
  explicit FeedbackUploader(content::BrowserContext* context);
  virtual ~FeedbackUploader();

  void QueueReport(scoped_ptr<std::string> data);

 private:
  friend class FeedbackUploaderTest;
  struct ReportsUploadTimeComparator {
    bool operator()(const FeedbackReport& a, const FeedbackReport& b) const;
  };

  // Dispatches the report to be uploaded.
  void DispatchReport(scoped_ptr<std::string> data);

  // Update our timer for uploading the next report.
  void UpdateUploadTimer();

  // Requeue this report with a delay.
  void RetryReport(scoped_ptr<std::string> data);

  void setup_for_test(const ReportDataCallback& dispatch_callback,
                      const base::TimeDelta& retry_delay);

  // Browser context this uploader was created for.
  content::BrowserContext* context_;
  // Timer to upload the next report at.
  base::OneShotTimer<FeedbackUploader> upload_timer_;
  // Priority queue of reports prioritized by the time the report is supposed
  // to be uploaded at.
  std::priority_queue<FeedbackReport,
                      std::vector<FeedbackReport>,
                      ReportsUploadTimeComparator> reports_queue_;

  std::vector<FeedbackReport> loaded_reports_;

  ReportDataCallback dispatch_callback_;
  base::TimeDelta retry_delay_;

  DISALLOW_COPY_AND_ASSIGN(FeedbackUploader);
};

}  // namespace feedback

#endif  // CHROME_BROWSER_FEEDBACK_FEEDBACK_UPLOADER_H_