// Copyright 2019 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "components/performance_manager/execution_context_priority/root_vote_observer.h"

#include "components/performance_manager/graph/frame_node_impl.h"
#include "components/performance_manager/graph/worker_node_impl.h"
#include "components/performance_manager/public/execution_context/execution_context.h"

namespace performance_manager {

namespace execution_context_priority {

namespace {

// Sets the priority of an execution context.
void SetPriorityAndReason(
    const execution_context::ExecutionContext* execution_context,
    const PriorityAndReason& priority_and_reason) {
  // No property changes while the node is leaving graph.
  if (execution_context->GetNodeState() == NodeState::kLeavingGraph) {
    return;
  }

  switch (execution_context->GetType()) {
    case execution_context::ExecutionContextType::kFrameNode:
      FrameNodeImpl::FromNode(execution_context->GetFrameNode())
          ->SetPriorityAndReason(priority_and_reason);
      break;
    case execution_context::ExecutionContextType::kWorkerNode:
      WorkerNodeImpl::FromNode(execution_context->GetWorkerNode())
          ->SetPriorityAndReason(priority_and_reason);
      break;
  }
}

}  // namespace

RootVoteObserver::RootVoteObserver() = default;

RootVoteObserver::~RootVoteObserver() = default;

VotingChannel RootVoteObserver::GetVotingChannel() {
  DCHECK_EQ(0u, voting_channel_factory_.voting_channels_issued());
  auto channel = voting_channel_factory_.BuildVotingChannel();
  voter_id_ = channel.voter_id();
  return channel;
}

void RootVoteObserver::OnVoteSet(VoterId voter_id,
                                 const ExecutionContext* execution_context,
                                 const std::optional<Vote>& vote) {
  DCHECK_EQ(voter_id_, voter_id);
  if (vote.has_value()) {
    SetPriorityAndReason(execution_context,
                         PriorityAndReason(vote->value(), vote->reason()));
  } else {
    SetPriorityAndReason(
        execution_context,
        PriorityAndReason(base::Process::Priority::kMinValue,
                          FrameNodeImpl::kDefaultPriorityReason));
  }
}

}  // namespace execution_context_priority
}  // namespace performance_manager