// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_ANIMATION_CSS_INTERPOLATION_ENVIRONMENT_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_ANIMATION_CSS_INTERPOLATION_ENVIRONMENT_H_

#include "third_party/blink/renderer/core/animation/interpolation_types_map.h"
#include "third_party/blink/renderer/core/css/resolver/style_resolver_state.h"
#include "third_party/blink/renderer/platform/wtf/allocator/allocator.h"

namespace blink {

class CascadeResolver;
class ComputedStyle;
class StyleCascade;

class CSSInterpolationEnvironment {
  STACK_ALLOCATED();

 public:
  CSSInterpolationEnvironment(const InterpolationTypesMap& map,
                              StyleResolverState& state,
                              StyleCascade* cascade,
                              CascadeResolver* cascade_resolver)
      : interpolation_types_map_(map),
        state_(&state),
        base_style_(state.StyleBuilder().GetBaseComputedStyle()),
        animation_controls_style_(base_style_),
        cascade_(cascade),
        cascade_resolver_(cascade_resolver) {}

  CSSInterpolationEnvironment(const InterpolationTypesMap& map,
                              StyleResolverState& state)
      : interpolation_types_map_(map), state_(&state) {}

  CSSInterpolationEnvironment(const InterpolationTypesMap& map,
                              const ComputedStyle& base_style,
                              const ComputedStyle& animation_controls_style)
      : interpolation_types_map_(map),
        base_style_(&base_style),
        animation_controls_style_(&animation_controls_style) {}

  const InterpolationTypesMap& GetInterpolationTypesMap() const {
    return interpolation_types_map_;
  }

  StyleResolverState& GetState() {
    DCHECK(state_);
    return *state_;
  }
  const StyleResolverState& GetState() const {
    DCHECK(state_);
    return *state_;
  }

  const ComputedStyle& BaseStyle() const {
    DCHECK(base_style_);
    return *base_style_;
  }

  // This is the style that should be used for properties that control
  // animation behavior.  This is usually the same as BaseStyle, except in the
  // case of the interpolation environment used for the before-change style
  // for CSS transitions.  In that case, the AnimationControlsStyle() is the
  // after-change style.
  const ComputedStyle& AnimationControlsStyle() const {
    DCHECK(animation_controls_style_);
    return *animation_controls_style_;
  }

  // Eliminates substitution functions, and handles other cascade interactions,
  // such as 'revert', 'revert-layer', etc.
  //
  // The TreeScope is the tree scope of the associated @keyframes rule
  // (if any).
  //
  // TODO(crbug.com/985023): This effective violates const.
  const CSSValue* Resolve(const PropertyHandle&,
                          const CSSValue*,
                          const TreeScope*) const;

  // Set by the caller of InterpolationType::Apply when one of the values
  // being interpolated originated from attr(), so that the applied value can
  // be marked as attr-tainted.
  bool IsAttrTainted() const { return is_attr_tainted_; }
  void SetIsAttrTainted(bool is_attr_tainted) {
    is_attr_tainted_ = is_attr_tainted;
  }

 private:
  const InterpolationTypesMap& interpolation_types_map_;
  StyleResolverState* state_ = nullptr;
  const ComputedStyle* base_style_ = nullptr;
  const ComputedStyle* animation_controls_style_ = nullptr;
  StyleCascade* cascade_ = nullptr;
  CascadeResolver* cascade_resolver_ = nullptr;
  bool is_attr_tainted_ = false;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_ANIMATION_CSS_INTERPOLATION_ENVIRONMENT_H_