chrome/browser/ui/views/tabs/tab_animation.h

// Copyright 2019 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.

#ifndef CHROME_BROWSER_UI_VIEWS_TABS_TAB_ANIMATION_H_
#define CHROME_BROWSER_UI_VIEWS_TABS_TAB_ANIMATION_H_

#include "base/callback.h"
#include "base/time/time.h"
#include "chrome/browser/ui/views/tabs/tab_animation_state.h"
#include "chrome/browser/ui/views/tabs/tab_strip_layout_types.h"

class TabWidthConstraints;

// Interpolates between TabAnimationStates. Apply the current state to a tab
// to animate that tab.
class TabAnimation {
 public:
  static constexpr base::TimeDelta kAnimationDuration =
      base::TimeDelta::FromMilliseconds(200);

  // Creates a TabAnimation for a tab with no active animations.
  explicit TabAnimation(TabAnimationState static_state);
  TabAnimation(const TabAnimation&) = delete;
  TabAnimation& operator=(const TabAnimation&) = delete;
  ~TabAnimation();

  // Returns whether this tab is currently animating closed.
  bool IsClosing() const;

  // Returns whether this tab has finished animating closed.
  bool IsClosed() const;

  // Animates this tab from its current state to |target_state_|.
  // If an animation is already running, the duration is reset.
  void AnimateTo(TabAnimationState target_state);

  // Animates this tab from its current state to |target_state_|.
  // Keeps the current remaining animation duration.
  void RetargetTo(TabAnimationState target_state);

  void CompleteAnimation();

  TabAnimationState target_state() const { return target_state_; }
  base::TimeDelta GetTimeRemaining() const;

  // Returns the TabWidthConstraints for the current state of the animation.
  TabWidthConstraints GetCurrentTabWidthConstraints(
      const TabLayoutConstants& layout_constants,
      const TabSizeInfo& size_info) const;

 private:
  friend class TabAnimationTest;
  FRIEND_TEST_ALL_PREFIXES(TabAnimationTest, ReplacedAnimationRestartsDuration);

  TabAnimationState GetCurrentState() const;

  TabAnimationState initial_state_;
  TabAnimationState target_state_;
  base::TimeTicks start_time_;
  base::TimeDelta duration_;
};

#endif  // CHROME_BROWSER_UI_VIEWS_TABS_TAB_ANIMATION_H_