WIP

chrome/browser/policy/policy_change_watcher.cc

Index: chrome/browser/policy/policy_change_watcher.cc
diff --git a/chrome/browser/policy/policy_change_watcher.cc b/chrome/browser/policy/policy_change_watcher.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0bc86ab2b4471f3e1be451492f0edb564cbc9522
--- /dev/null
+++ b/chrome/browser/policy/policy_change_watcher.cc
@@ -0,0 +1,190 @@
+// Copyright (c) 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.
+
+#include "chrome/browser/policy/policy_change_watcher.h"
+
+#include "base/json/json_writer.h"
+  #include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/prefs/pref_registry_simple.h"
+#include "base/prefs/pref_service.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/values.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/policy/policy_namespace.h"
+#include "chrome/browser/prefs/pref_registry_syncable.h"
+#include "chrome/browser/prefs/scoped_user_pref_update.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/common/pref_names.h"
+#include "crypto/sha2.h"
+
+namespace policy {
+
+PolicyServiceChangeWatcher::PolicyServiceChangeWatcher(
+    PolicyService* policy_service,
+    const std::string& current_hash)
+    : domains_pending_initialization_(0),
+      current_hash_(current_hash),
+      policy_service_(policy_service) {
+}
+
+PolicyServiceChangeWatcher::~PolicyServiceChangeWatcher() {
+  for (size_t i = 0; i < POLICY_DOMAIN_SIZE; ++i)
+    policy_service_->RemoveObserver(static_cast<PolicyDomain>(i), this);
+}
+
+void PolicyServiceChangeWatcher::OnPolicyUpdated(const PolicyNamespace& ns,
+                                                 const PolicyMap& previous,
+                                                 const PolicyMap& current) {
+  if (is_initialization_complete())
+    CheckIfPolicyChanged(policy_service_->GetAllPolicies());
+}
+
+void PolicyServiceChangeWatcher::OnPolicyServiceInitialized(
+    PolicyDomain domain) {
+  --domains_pending_initialization_;
+  if (is_initialization_complete())
+    CheckIfPolicyChanged(policy_service_->GetAllPolicies());
+}
+
+void PolicyServiceChangeWatcher::Init() {
+  for (size_t i = 0; i < POLICY_DOMAIN_SIZE; ++i) {
+    PolicyDomain domain = static_cast<PolicyDomain>(i);
+    policy_service_->AddObserver(domain, this);
+    if (!policy_service_->IsInitializationComplete(domain))
+      ++domains_pending_initialization_;
+  }
+  if (is_initialization_complete())
+    CheckIfPolicyChanged(policy_service_->GetAllPolicies());
+}
+
+void PolicyServiceChangeWatcher::CheckIfPolicyChanged(
+    const PolicyBundle& bundle) {
+  scoped_ptr<base::DictionaryValue> policy(new base::DictionaryValue);
+  for (PolicyBundle::const_iterator bundle_it = bundle.begin();
+       bundle_it != bundle.end(); ++bundle_it) {
+    if (bundle_it->second->empty())
+      continue;
+
+    base::DictionaryValue* map = new base::DictionaryValue;
+    for (PolicyMap::const_iterator map_it = bundle_it->second->begin();
+         map_it != bundle_it->second->end(); ++map_it) {
+      base::DictionaryValue* entry = new base::DictionaryValue;
+      entry->SetInteger("level", map_it->second.level);
+      entry->SetInteger("scope", map_it->second.scope);
+      entry->Set("value", map_it->second.value->DeepCopy());
+      map->Set(map_it->first, entry);
+    }
+    const PolicyNamespace& ns = bundle_it->first;
+    policy->Set(base::IntToString(ns.domain) + ":" + ns.component_id, map);
+  }
+
+  std::string json;
+  base::JSONWriter::Write(policy.get(), &json);
+  char hash[crypto::kSHA256Length];
+  crypto::SHA256HashString(json, &hash, sizeof(hash));
+  const std::string new_hash = base::HexEncode(&hash, sizeof(hash));
+
+  if (new_hash != current_hash_) {
+    current_hash_ = new_hash;
+    OnPolicyChanged();
+  }
+}
+
+DevicePolicyChangeWatcher::Observer::~Observer() {
+}
+
+DevicePolicyChangeWatcher::DevicePolicyChangeWatcher()
+    : PolicyServiceChangeWatcher(g_browser_process->policy_service(), "") {
+  Init();
+  LOG(ERROR) << "*** DevicePolicyChangeWatcher UP";
+}
+
+DevicePolicyChangeWatcher::~DevicePolicyChangeWatcher() {
+  LOG(ERROR) << "*** DevicePolicyChangeWatcher DOWN";
+}
+
+void DevicePolicyChangeWatcher::AddObserver(Observer* observer) {
+  observers_.AddObserver(observer);
+  if (is_initialization_complete())
+    observer->OnDevicePolicyStatusChanged(ListUsersWithChangedDevicePolicy());
+}
+
+void DevicePolicyChangeWatcher::RemoveObserver(Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+// static
+void DevicePolicyChangeWatcher::RegisterPrefs(PrefRegistrySimple* registry) {
+  registry->RegisterDictionaryPref(prefs::kDevicePolicyHashes);
+}
+
+void DevicePolicyChangeWatcher::AcknowledgePolicyChange(
+    const std::string& username) {
+  if (!is_initialization_complete())
+    return;
+
+  DictionaryPrefUpdate pref_update(g_browser_process->local_state(),
+                                   prefs::kDevicePolicyHashes);
+  pref_update->SetWithoutPathExpansion(
+      username,
+      base::Value::CreateStringValue(current_hash()));
+
+  NotifyDevicePolicyStatusChanged();
+}
+
+std::vector<std::string>
+    DevicePolicyChangeWatcher::ListUsersWithChangedDevicePolicy() const {
+  DCHECK(is_initialization_complete());
+  std::vector<std::string> users_with_changed_device_policy;
+  for (base::DictionaryValue::Iterator it(
+           *g_browser_process->local_state()->GetDictionary(
+               prefs::kDevicePolicyHashes));
+       !it.IsAtEnd(); it.Advance()) {
+    std::string previous_hash;
+    if (!it.value().GetAsString(&previous_hash) ||
+        previous_hash != current_hash()) {
+      users_with_changed_device_policy.push_back(it.key());
+    }
+  }
+  return users_with_changed_device_policy;
+}
+
+void DevicePolicyChangeWatcher::NotifyDevicePolicyStatusChanged() {
+  std::vector<std::string> users_with_changed_device_policy =
+      ListUsersWithChangedDevicePolicy();
+  FOR_EACH_OBSERVER(
+      Observer,
+      observers_,
+      OnDevicePolicyStatusChanged(users_with_changed_device_policy));
+}
+
+void DevicePolicyChangeWatcher::OnPolicyChanged() {
+  NotifyDevicePolicyStatusChanged();
+}
+
+UserPolicyChangeWatcher::UserPolicyChangeWatcher(Profile* profile)
+    : PolicyServiceChangeWatcher(
+          profile->GetPolicyService(),
+          profile->GetPrefs()->GetString(prefs::kUserPolicyHash)) {
+  Init();
+}
+
+UserPolicyChangeWatcher::~UserPolicyChangeWatcher() {
+}
+
+// static
+void UserPolicyChangeWatcher::RegisterUserPrefs(
+    PrefRegistrySyncable* registry) {
+  registry->RegisterStringPref(prefs::kUserPolicyHash,
+                               std::string(),
+                               PrefRegistrySyncable::UNSYNCABLE_PREF);
+}
+
+void UserPolicyChangeWatcher::OnPolicyChanged() {
+  LOG(ERROR) << "New user policy: " << current_hash();
+}
+
+
+}  // namespace policy