This CL adds AccountId object to be used as User Account identifier.

This is part of transition to AccountId.

BUG=468875
TEST=manual

Review URL: https://codereview.chromium.org/1406143002

Cr-Commit-Position: refs/heads/master@{#354624}

5 files changed, 217 insertions, 0 deletions

diff --git a/components/signin/core/account_id/BUILD.gn b/components/signin/core/account_id/BUILD.gn
new file mode 100644
index 0000000..2c0b69b
--- /dev/null
+++ b/components/signin/core/account_id/BUILD.gn
@@ -0,0 +1,14 @@
+# Copyright 2014 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.
+
+source_set("account_id") {
+  sources = [
+    "account_id.cc",
+    "account_id.h",
+  ]
+
+  deps = [
+    "//base",
+  ]
+}
diff --git a/components/signin/core/account_id/DEPS b/components/signin/core/account_id/DEPS
new file mode 100644
index 0000000..48e8875
--- /dev/null
+++ b/components/signin/core/account_id/DEPS
@@ -0,0 +1,2 @@
+include_rules = [
+]
diff --git a/components/signin/core/account_id/account_id.cc b/components/signin/core/account_id/account_id.cc
new file mode 100644
index 0000000..65b237f
--- /dev/null
+++ b/components/signin/core/account_id/account_id.cc
@@ -0,0 +1,128 @@
+// Copyright 2015 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.
+
+#include "components/signin/core/account_id/account_id.h"
+
+#include <functional>
+
+#include "base/memory/singleton.h"
+#include "google_apis/gaia/gaia_auth_util.h"
+
+namespace {
+
+// Known account types.
+const char kGoogle[] = "google";
+
+struct GoogleStringSingleton {
+  GoogleStringSingleton() : google(kGoogle) {}
+
+  static GoogleStringSingleton* GetInstance() {
+    return base::Singleton<GoogleStringSingleton>::get();
+  }
+
+  const std::string google;
+};
+
+}  // anonymous namespace
+
+struct AccountId::EmptyAccountId {
+  EmptyAccountId() : user_id() {}
+  const AccountId user_id;
+
+  static EmptyAccountId* GetInstance() {
+    return base::Singleton<EmptyAccountId>::get();
+  }
+};
+
+AccountId::AccountId() {}
+
+AccountId::AccountId(const std::string& gaia_id, const std::string& user_email)
+    : gaia_id_(gaia_id), user_email_(user_email) {
+  // TODO (alemate): DCHECK(!email.empty());
+  // TODO (alemate): check gaia_id is not empty once it is required.
+}
+
+AccountId::AccountId(const AccountId& other)
+    : gaia_id_(other.gaia_id_), user_email_(other.user_email_) {}
+
+bool AccountId::operator==(const AccountId& other) const {
+  return (this == &other) ||
+         (gaia_id_ == other.gaia_id_ && user_email_ == other.user_email_) ||
+         (!gaia_id_.empty() && gaia_id_ == other.gaia_id_) ||
+         (!user_email_.empty() && user_email_ == other.user_email_);
+}
+
+bool AccountId::operator!=(const AccountId& other) const {
+  return !operator==(other);
+}
+
+bool AccountId::operator<(const AccountId& right) const {
+  // TODO (alemate): update this once all AccountId members are filled.
+  return user_email_ < right.user_email_;
+}
+
+bool AccountId::empty() const {
+  return gaia_id_.empty() && user_email_.empty();
+}
+
+bool AccountId::is_valid() const {
+  return /* !gaia_id_.empty() && */ !user_email_.empty();
+}
+
+void AccountId::clear() {
+  gaia_id_.clear();
+  user_email_.clear();
+}
+
+const std::string& AccountId::GetAccountType() const {
+  return GoogleStringSingleton::GetInstance()->google;
+}
+
+const std::string& AccountId::GetGaiaId() const {
+  return gaia_id_;
+}
+
+const std::string& AccountId::GetUserEmail() const {
+  return user_email_;
+}
+
+void AccountId::SetGaiaId(const std::string& gaia_id) {
+  DCHECK(!gaia_id.empty());
+  gaia_id_ = gaia_id;
+}
+
+void AccountId::SetUserEmail(const std::string& email) {
+  DCHECK(!email.empty());
+  user_email_ = email;
+}
+
+// static
+AccountId AccountId::FromUserEmail(const std::string& email) {
+  // TODO (alemate): DCHECK(!email.empty());
+  return AccountId(std::string() /* gaia_id */, email);
+}
+
+AccountId AccountId::FromGaiaId(const std::string& gaia_id) {
+  DCHECK(!gaia_id.empty());
+  return AccountId(gaia_id, std::string() /* email */);
+}
+
+// static
+AccountId AccountId::FromUserEmailGaiaId(const std::string& email,
+                                         const std::string& gaia_id) {
+  DCHECK(!(email.empty() && gaia_id.empty()));
+  return AccountId(gaia_id, email);
+}
+
+const AccountId& EmptyAccountId() {
+  return AccountId::EmptyAccountId::GetInstance()->user_id;
+}
+
+namespace BASE_HASH_NAMESPACE {
+
+std::size_t hash<AccountId>::operator()(const AccountId& user_id) const {
+  return hash<std::string>()(user_id.GetUserEmail());
+}
+
+}  // namespace BASE_HASH_NAMESPAC
diff --git a/components/signin/core/account_id/account_id.h b/components/signin/core/account_id/account_id.h
new file mode 100644
index 0000000..73be450
--- /dev/null
+++ b/components/signin/core/account_id/account_id.h
@@ -0,0 +1,72 @@
+// Copyright 2015 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 COMPONENTS_SIGNIN_CORE_ACCOUNT_ID_ACCOUNT_ID_H_
+#define COMPONENTS_SIGNIN_CORE_ACCOUNT_ID_ACCOUNT_ID_H_
+
+#include <string>
+#include "base/containers/hash_tables.h"
+
+// Type that contains enough information to identify user.
+//
+// TODO (alemate): we are in the process of moving away from std::string as a
+// type for storing user identifier to AccountId. At this time GaiaId is mostly
+// empty, so this type is used as a replacement for e-mail string.
+// But in near future AccountId will become full feature user identifier.
+class AccountId {
+ public:
+  struct EmptyAccountId;
+
+  AccountId(const AccountId& other);
+
+  bool operator==(const AccountId& other) const;
+  bool operator!=(const AccountId& other) const;
+  bool operator<(const AccountId& right) const;
+
+  // empty() is deprecated. Use !is_valid() instead.
+  bool empty() const;
+  bool is_valid() const;
+  void clear();
+
+  const std::string& GetAccountType() const;
+  const std::string& GetGaiaId() const;
+  const std::string& GetUserEmail() const;
+
+  void SetGaiaId(const std::string& gaia_id);
+  void SetUserEmail(const std::string& email);
+
+  // This method is to be used during transition period only.
+  static AccountId FromUserEmail(const std::string& user_email);
+  // This method is to be used during transition period only.
+  static AccountId FromGaiaId(const std::string& gaia_id);
+  // This method is the preferred way to construct AccountId if you have
+  // full account information.
+  static AccountId FromUserEmailGaiaId(const std::string& user_email,
+                                       const std::string& gaia_id);
+
+  // std::string Serialize() const;
+  // static AccountId Deserialize(const std::string& serialized);
+
+ private:
+  AccountId();
+  AccountId(const std::string& gaia_id, const std::string& user_email);
+
+  std::string gaia_id_;
+  std::string user_email_;
+};
+
+// Returns a reference to a singleton.
+const AccountId& EmptyAccountId();
+
+namespace BASE_HASH_NAMESPACE {
+
+// Implement hashing of AccountId, so it can be used as a key in STL containers.
+template <>
+struct hash<AccountId> {
+  std::size_t operator()(const AccountId& user_id) const;
+};
+
+}  // namespace BASE_HASH_NAMESPACE
+
+#endif  // COMPONENTS_SIGNIN_CORE_ACCOUNT_ID_ACCOUNT_ID_H_
diff --git a/components/signin/core/browser/BUILD.gn b/components/signin/core/browser/BUILD.gn
index a7a0157..d27e727 100644
--- a/components/signin/core/browser/BUILD.gn
+++ b/components/signin/core/browser/BUILD.gn
@@ -82,6 +82,7 @@ source_set("browser") {
     "//components/metrics",
     "//components/os_crypt",
     "//components/webdata/common",
+    "//components/signin/core/account_id",
   ]
 
   if (is_chromeos) {