// Copyright (c) 2011 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 WEBKIT_QUOTA_QUOTA_DATABASE_H_
#define WEBKIT_QUOTA_QUOTA_DATABASE_H_

#include <set>
#include <string>

#include "base/basictypes.h"
#include "base/callback.h"
#include "base/file_path.h"
#include "base/gtest_prod_util.h"
#include "base/memory/scoped_ptr.h"
#include "base/time.h"
#include "base/timer.h"
#include "googleurl/src/gurl.h"
#include "webkit/quota/quota_types.h"

namespace sql {
class Connection;
class MetaTable;
class Statement;
}

class GURL;

namespace quota {

class SpecialStoragePolicy;

// All the methods of this class must run on the DB thread.
class QuotaDatabase {
 public:
  // If 'path' is empty, an in memory database will be used.
  explicit QuotaDatabase(const FilePath& path);
  ~QuotaDatabase();

  void CloseConnection();

  bool GetHostQuota(const std::string& host, StorageType type, int64* quota);
  bool SetHostQuota(const std::string& host, StorageType type, int64 quota);

  bool SetOriginLastAccessTime(const GURL& origin, StorageType type,
                               base::Time last_access_time);

  // Register |origins| to Database with |used_count| = 0 and
  // specified |last_access_time|.
  bool RegisterOrigins(const std::set<GURL>& origins,
                       StorageType type,
                       base::Time last_access_time);

  bool DeleteHostQuota(const std::string& host, StorageType type);
  bool DeleteOriginLastAccessTime(const GURL& origin, StorageType type);

  bool GetGlobalQuota(StorageType type, int64* quota);
  bool SetGlobalQuota(StorageType type, int64 quota);

  // Sets |origin| to the least recently used origin of origins not included
  // in |exceptions| and not granted the special unlimited storage right.
  // It returns false when it failed in accessing the database.
  // |origin| is set to empty when there is no matching origin.
  bool GetLRUOrigin(StorageType type,
                    const std::set<GURL>& exceptions,
                    SpecialStoragePolicy* special_storage_policy,
                    GURL* origin);

  // Returns false if SetOriginDatabaseBootstrapped has never
  // been called before, which means existing origins may not have been
  // registered.
  bool IsOriginDatabaseBootstrapped();
  bool SetOriginDatabaseBootstrapped(bool bootstrap_flag);

 private:
  struct QuotaTableEntry {
    std::string host;
    StorageType type;
    int64 quota;
  };
  friend bool operator <(const QuotaTableEntry& lhs,
                         const QuotaTableEntry& rhs);

  struct LastAccessTimeTableEntry {
    GURL origin;
    StorageType type;
    int used_count;
    base::Time last_access_time;
  };
  friend bool operator <(const LastAccessTimeTableEntry& lhs,
                         const LastAccessTimeTableEntry& rhs);

  typedef base::Callback<bool (const QuotaTableEntry&)> QuotaTableCallback;
  typedef base::Callback<bool (const LastAccessTimeTableEntry&)>
      LastAccessTimeTableCallback;

  // For long-running transactions support.  We always keep a transaction open
  // so that multiple transactions can be batched.  They are flushed
  // with a delay after a modification has been made.  We support neither
  // nested transactions nor rollback (as we don't need them for now).
  void Commit();
  void ScheduleCommit();

  bool FindOriginUsedCount(const GURL& origin,
                           StorageType type,
                           int* used_count);

  bool LazyOpen(bool create_if_needed);
  bool EnsureDatabaseVersion();
  bool CreateSchema();
  bool ResetSchema();

  // |callback| may return false to stop reading data
  bool DumpQuotaTable(QuotaTableCallback* callback);
  bool DumpLastAccessTimeTable(LastAccessTimeTableCallback* callback);


  FilePath db_file_path_;

  scoped_ptr<sql::Connection> db_;
  scoped_ptr<sql::MetaTable> meta_table_;
  bool is_recreating_;
  bool is_disabled_;

  base::OneShotTimer<QuotaDatabase> timer_;

  friend class QuotaDatabaseTest;
  friend class QuotaManager;

  DISALLOW_COPY_AND_ASSIGN(QuotaDatabase);
};

}  // namespace quota

#endif  // WEBKIT_QUOTA_QUOTA_DATABASE_H_