{% from 'templates/macros.tmpl' import license, print_if, source_files_for_generated_file %}
{% from 'templates/fields/field.tmpl' import encode, getter_expression, setter_expression, declare_storage, fieldwise_compare, fieldwise_copy, fieldwise_diff, fieldwise_pointer_compare_inherited %}
{% from 'templates/fields/group.tmpl' import declare_field_group_class %}
{{license()}}

{{source_files_for_generated_file(template_file, input_files)}}

#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_STYLE_COMPUTED_STYLE_BASE_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_STYLE_COMPUTED_STYLE_BASE_H_

#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/core/layout/layout_theme.h"
#include "third_party/blink/renderer/core/style/computed_style_constants.h"
#include "third_party/blink/renderer/core/style/data_ref.h"
#include "third_party/blink/renderer/core/style/member_copy.h"
#include "third_party/blink/renderer/core/style/computed_style_initial_values.h"
{% for path in include_paths %}
#include "{{path}}"
{% endfor %}

{# Each field template has macros that we can call to generate specific
   aspects of the field (e.g. getters, setters).
#}
{% import 'templates/fields/keyword.tmpl' as keyword %}
{% import 'templates/fields/multi_keyword.tmpl' as multi_keyword %}
{% import 'templates/fields/primitive.tmpl' as primitive %}
{% import 'templates/fields/monotonic_flag.tmpl' as monotonic_flag %}
{% import 'templates/fields/external.tmpl' as external %}
{% import 'templates/fields/pointer.tmpl' as pointer %}
{% from 'templates/fields/field.tmpl' import encode %}
{% set field_templates = {
     'keyword': keyword,
     'multi_keyword': multi_keyword,
     'primitive': primitive,
     'monotonic_flag': monotonic_flag,
     'external': external,
     'pointer': pointer
   } %}

namespace blink {

// Forward declaration for diff functions.
class ComputedStyle;

// The generated portion of ComputedStyle. For more info, see the header comment
// in ComputedStyle.h.
//
// ComputedStyleBase is a generated class that stores data members or 'fields'
// used in ComputedStyle. These fields can represent CSS properties or internal
// style information.
//
// STORAGE:
//
// Fields are organised in a tree structure, where a node (called a 'group')
// stores a set of fields and a set of pointers to child nodes (called
// 'subgroups'). We can visualise the tree structure with ComputedStyleBase as
// the root node:
//
// ComputedStyleBase (fields: display, vertical-align, ...)
//  |- StyleSurroundData (fields: padding, border, ...)
//  |- StyleBoxData (fields: width, height, ...)
//  |- ...
//  |- StyleRareNonInheritedData (fields: box-shadow, text-overflow, ...)
//      |- StyleFlexibleBoxData (fields: flex-direction, flex-wrap, ...)
//      |- ...
//
// This design saves memory by allowing multiple ComputedStyleBases to share the
// same instance of a subgroup. For example, if a page never uses flex box
// properties, then every ComputedStyleBase can share the same instance of
// StyleFlexibleBoxData. Without this sharing, we would need to allocate a copy
// of all the flex box fields for every ComputedStyleBase. Similarly, when an
// element inherits from its parent, its ComputedStyleBase can simply share all
// of its subgroups with the parent's.
//
// INTERFACE:
//
// The functions generated for a field is determined by its 'template'. For
// example, a field with the 'keyword' template has only one setter, whereas an
// 'external' field has an extra setter that takes an rvalue reference. A list
// of the available templates can be found in css_properties.json5.
class ComputedStyleBase {
 public:
  inline bool IndependentInheritedEqual(const ComputedStyleBase& o) const {
    return (
        {{fieldwise_compare(computed_style, computed_style.all_fields
            |selectattr("is_property")
            |selectattr("is_inherited")
            |selectattr("is_independent")
            |rejectattr("is_semi_independent_variable")
            |list
          )|indent(8)}}
    );
  }

  inline bool NonIndependentInheritedEqual(const ComputedStyleBase& o) const {
    return (
        {{fieldwise_compare(computed_style, computed_style.all_fields
            |selectattr("is_property")
            |selectattr("is_inherited")
            |rejectattr("is_independent")
            |rejectattr("is_semi_independent_variable")
            |list
          )|indent(8)}}
    );
  }

  inline bool InheritedVariablesEqual(const ComputedStyleBase& o) const {
    return (
        {{fieldwise_compare(computed_style, computed_style.all_fields
            |selectattr("is_property")
            |selectattr("is_inherited")
            |rejectattr("is_independent")
            |selectattr("is_semi_independent_variable")
            |list
          )|indent(8)}}
    );
  }

  inline bool InheritedEqual(const ComputedStyleBase& o) const {
    return IndependentInheritedEqual(o) && NonIndependentInheritedEqual(o);
  }

  inline bool NonInheritedEqual(const ComputedStyleBase& o) const {
    return (
        {{fieldwise_compare(computed_style, computed_style.all_fields
            |selectattr("is_property")
            |rejectattr("is_inherited")
            |list
          )|indent(8)}}
    );
  }

  inline bool InheritedDataShared(const ComputedStyleBase& o) const {
    return (
        {{fieldwise_pointer_compare_inherited(computed_style)|indent(8)}}
    );
  }

  enum IsAtShadowBoundary {
    kAtShadowBoundary,
    kNotAtShadowBoundary,
  };

  void InheritFrom(const ComputedStyleBase& other,
                                      IsAtShadowBoundary isAtShadowBoundary);
  void InheritCustomPropertiesFrom(const ComputedStyleBase& other) {
    inherited_variables_data_ = other.inherited_variables_data_;
  }

  void CopyNonInheritedFromCached(
      const ComputedStyleBase& other);

  // Copies the values of any independent inherited properties from the parent
  // style that are marked as inherited by this style.
  void PropagateIndependentInheritedProperties(
      const ComputedStyleBase& parentStyle);

  {% for name, groups_to_diff in diff_functions_map.items() %}
  static bool {{name}}(const ComputedStyle& a, const ComputedStyle& b);
  {% endfor %}

  // Fields.
  // TODO(sashab): Remove initialFoo() static methods and update callers to
  // use resetFoo(), which can be more efficient.

  {% for field in computed_style.all_fields|sort(attribute='name') %}
  // {{field.property_name}}
  {{field_templates[field.field_template].decl_public_methods(field)|indent(2)}}

  {% endfor %}
 private:
  {% for subgroup in computed_style.subgroups %}
  {{declare_field_group_class(subgroup)|indent(2)}}

  {% endfor %}

 protected:
  // Constructor and destructor are protected so that only the parent class ComputedStyle
  // can instantiate this class.
  ComputedStyleBase();

  {% for field in computed_style.all_fields|sort(attribute='name') %}
  {% if field.field_template not in ('pointer',) %}
  // {{field.property_name}}
  {{field_templates[field.field_template].decl_protected_methods(field)|indent(2)}}

  {% endif %}
  {% endfor %}

  ~ComputedStyleBase() = default;

 private:
  // Storage.
  {% for subgroup in computed_style.subgroups %}
  DataRef<{{subgroup.type_name}}> {{subgroup.member_name}};
  {% endfor %}

  {% for field in computed_style.fields %}
  {{declare_storage(field)}}
  {% endfor %}
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_STYLE_COMPUTED_STYLE_BASE_H_