// 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 "cc/input/scroll_state.h"

#include <utility>

#include "cc/trees/layer_tree_impl.h"
#include "cc/trees/scroll_node.h"

namespace cc {

ScrollState::ScrollState(ScrollStateData data)
    : data_(data), layer_tree_impl_(nullptr) {}

ScrollState::ScrollState(const ScrollState& other) = default;

ScrollState::~ScrollState() {}

void ScrollState::ConsumeDelta(double x, double y) {
  data_.delta_x -= x;
  data_.delta_y -= y;

  if (x || y)
    data_.delta_consumed_for_scroll_sequence = true;
}

void ScrollState::DistributeToScrollChainDescendant() {
  if (!scroll_chain_.empty()) {
    ScrollNode* next = scroll_chain_.front();
    scroll_chain_.pop_front();

    ScrollTree& scroll_tree = layer_tree_impl_->property_trees()->scroll_tree;
    scroll_tree.DistributeScroll(next, this);
  }
}

}  // namespace cc