Revert of Revert of Adding CopresenceState

components/copresence/copresence_state_impl.cc

Index: components/copresence/copresence_state_impl.cc
diff --git a/components/copresence/copresence_state_impl.cc b/components/copresence/copresence_state_impl.cc
new file mode 100644
index 0000000000000000000000000000000000000000..9a873d32e828df8e832ec4e9c1205b6da84af754
--- /dev/null
+++ b/components/copresence/copresence_state_impl.cc
@@ -0,0 +1,179 @@
+// 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.
+
+#include <set>
+
+#include "base/logging.h"
+#include "base/time/time.h"
+#include "components/copresence/copresence_state_impl.h"
+#include "components/copresence/proto/data.pb.h"
+#include "components/copresence/public/copresence_constants.h"
+#include "components/copresence/public/copresence_observer.h"
+
+namespace copresence {
+
+namespace {
+
+template<typename TokenType>
+void HandleCommonFields(const TokenType& new_token, TokenType* current_token) {
+  if (current_token->id.empty()) {
+    current_token->id = new_token.id;
+    current_token->medium = new_token.medium;
+    current_token->start_time = new_token.start_time;
+  } else {
+    DCHECK_EQ(new_token.id, current_token->id);
+    DCHECK_EQ(new_token.medium, current_token->medium);
+    DCHECK(new_token.start_time.is_null() ||
+           new_token.start_time == current_token->start_time);
+  }
+}
+
+void UpdateToken(const TransmittedToken& new_token,
+                 TransmittedToken* current_token) {
+  HandleCommonFields(new_token, current_token);
+
+  current_token->stop_time = new_token.stop_time;
+  current_token->broadcast_confirmed = new_token.broadcast_confirmed;
+}
+
+void UpdateToken(const ReceivedToken& new_token,
+                 ReceivedToken* current_token) {
+  HandleCommonFields(new_token, current_token);
+
+  current_token->last_time = new_token.last_time;
+  if (new_token.valid != ReceivedToken::UNKNOWN)
+    current_token->valid = new_token.valid;
+}
+
+}  // namespace
+
+
+// Public functions.
+
+CopresenceStateImpl::CopresenceStateImpl() {}
+
+CopresenceStateImpl::~CopresenceStateImpl() {}
+
+void CopresenceStateImpl::AddObserver(CopresenceObserver* observer) {
+  DCHECK(observer);
+  observers_.AddObserver(observer);
+}
+
+void CopresenceStateImpl::RemoveObserver(CopresenceObserver* observer) {
+  DCHECK(observer);
+  observers_.RemoveObserver(observer);
+}
+
+const std::vector<Directive>& CopresenceStateImpl::active_directives() const {
+  return active_directives_;
+}
+
+const std::map<std::string, TransmittedToken>&
+CopresenceStateImpl::transmitted_tokens() const {
+  return transmitted_tokens_;
+}
+
+const std::map<std::string, ReceivedToken>&
+CopresenceStateImpl::received_tokens() const {
+  return received_tokens_;
+}
+
+// TODO(ckehoe): Only send updates if the directives have really changed.
+void CopresenceStateImpl::UpdateDirectives(
+    const std::vector<Directive>& directives) {
+  active_directives_ = directives;
+  UpdateTransmittingTokens();
+  FOR_EACH_OBSERVER(CopresenceObserver, observers_, DirectivesUpdated());
+}
+
+void CopresenceStateImpl::UpdateTransmittedToken(
+    const TransmittedToken& token) {
+  UpdateToken(token, &transmitted_tokens_[token.id]);
+  FOR_EACH_OBSERVER(CopresenceObserver,
+                    observers_,
+                    TokenTransmitted(transmitted_tokens_[token.id]));
+}
+
+// TODO(ckehoe): Check which tokens are no longer heard and report them lost.
+void CopresenceStateImpl::UpdateReceivedToken(const ReceivedToken& token) {
+  DCHECK(!token.id.empty());
+
+  // TODO(ckehoe): Have CopresenceManagerImpl::AudioCheck() use this to check
+  // if we can hear our token, and delete the logic from the AudioManager.
+  if (transmitted_tokens_.count(token.id) > 0) {
+    transmitted_tokens_[token.id].broadcast_confirmed = true;
+    FOR_EACH_OBSERVER(CopresenceObserver,
+                      observers_,
+                      TokenTransmitted(transmitted_tokens_[token.id]));
+  } else {
+    ReceivedToken& stored_token = received_tokens_[token.id];
+    UpdateToken(token, &stored_token);
+
+    // The decoder doesn't track when this token was heard before,
+    // so it should just fill in the last_time.
+    // If we've never seen this token, we populate the start time too.
+    if (stored_token.start_time.is_null())
+      stored_token.start_time = token.last_time;
+
+    FOR_EACH_OBSERVER(CopresenceObserver,
+                      observers_,
+                      TokenReceived(stored_token));
+  }
+}
+
+void CopresenceStateImpl::UpdateTokenStatus(const std::string& token_id,
+                                            TokenStatus status) {
+  if (transmitted_tokens_.count(token_id) > 0) {
+    LOG_IF(ERROR, status != VALID)
+        << "Broadcast token " << token_id << " is invalid";
+  } else if (received_tokens_.count(token_id) > 0) {
+    received_tokens_[token_id].valid = status == VALID ?
+        ReceivedToken::VALID : ReceivedToken::INVALID;
+    FOR_EACH_OBSERVER(CopresenceObserver,
+                      observers_,
+                      TokenReceived(received_tokens_[token_id]));
+  } else {
+    LOG(ERROR) << "Got status update for unrecognized token " << token_id;
+  }
+}
+
+
+// Private functions.
+
+void CopresenceStateImpl::UpdateTransmittingTokens() {
+  std::set<std::string> tokens_to_update;
+  for (const auto& token_entry : transmitted_tokens_)
+    tokens_to_update.insert(token_entry.first);
+
+  for (const Directive& directive : active_directives_) {
+    const TokenInstruction& instruction = directive.token_instruction();
+    if (instruction.token_instruction_type() == TRANSMIT) {
+      tokens_to_update.erase(instruction.token_id());
+
+      TransmittedToken& token = transmitted_tokens_[instruction.token_id()];
+      token.id = instruction.token_id();
+      token.medium = instruction.medium();
+      token.start_time = base::Time::Now();
+      token.stop_time = base::Time::Now() +
+          base::TimeDelta::FromMilliseconds(directive.ttl_millis());
+
+      FOR_EACH_OBSERVER(CopresenceObserver,
+                        observers_,
+                        TokenTransmitted(token));
+    }
+  }
+
+  // Tokens not updated above are no longer transmitting.
+  base::Time now = base::Time::Now();
+  for (const std::string& token : tokens_to_update) {
+    if (transmitted_tokens_[token].stop_time > now)
+      transmitted_tokens_[token].stop_time = now;
+
+    FOR_EACH_OBSERVER(CopresenceObserver,
+                      observers_,
+                      TokenTransmitted(transmitted_tokens_[token]));
+  }
+}
+
+}  // namespace copresence