// Copyright 2020 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/frame_audible_voter.h"

#include <utility>

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

namespace performance_manager {
namespace execution_context_priority {

namespace {

// Returns a vote with the appropriate priority depending on if the frame is
// audible.
Vote GetVote(bool is_audible) {
  base::Process::Priority priority =
      is_audible ? base::Process::Priority::kUserBlocking
                 : base::Process::Priority::kMinValue;
  return Vote(priority, FrameAudibleVoter::kFrameAudibleReason);
}

}  // namespace

// static
const char FrameAudibleVoter::kFrameAudibleReason[] = "Frame audible.";

FrameAudibleVoter::FrameAudibleVoter() = default;

FrameAudibleVoter::~FrameAudibleVoter() = default;

void FrameAudibleVoter::InitializeOnGraph(Graph* graph,
                                          VotingChannel voting_channel) {
  voting_channel_ = std::move(voting_channel);

  graph->AddFrameNodeObserver(this);
}

void FrameAudibleVoter::TearDownOnGraph(Graph* graph) {
  graph->RemoveFrameNodeObserver(this);

  voting_channel_.Reset();
}

void FrameAudibleVoter::OnBeforeFrameNodeAdded(
    const FrameNode* frame_node,
    const FrameNode* pending_parent_frame_node,
    const PageNode* pending_page_node,
    const ProcessNode* pending_process_node,
    const FrameNode* pending_parent_or_outer_document_or_embedder) {
  SetVoteForFrame(frame_node);
}

void FrameAudibleVoter::OnBeforeFrameNodeRemoved(const FrameNode* frame_node) {
  voting_channel_.SetVote(frame_node, std::nullopt);
}

void FrameAudibleVoter::OnIsAudibleChanged(const FrameNode* frame_node) {
  SetVoteForFrame(frame_node);
}

void FrameAudibleVoter::SetVoteForFrame(const FrameNode* frame_node) {
  const Vote vote = GetVote(frame_node->IsAudible());
  voting_channel_.SetVote(frame_node, vote);
}

}  // namespace execution_context_priority
}  // namespace performance_manager