// Copyright 2024 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

module viz.mojom;

import "cc/mojom/element_id.mojom";
import "cc/mojom/hit_test_opaqueness.mojom";
import "cc/mojom/layer_type.mojom";
import "cc/mojom/paint_flags.mojom";
import "cc/mojom/render_surface_reason.mojom";
import "cc/mojom/synced_scroll_offset.mojom";
import "cc/mojom/ui_resource_id.mojom";
import "services/viz/public/mojom/compositing/copy_output_request.mojom";
import "services/viz/public/mojom/compositing/filter_operations.mojom";
import "services/viz/public/mojom/compositing/region_capture_bounds.mojom";
import "services/viz/public/mojom/compositing/resource_id.mojom";
import "services/viz/public/mojom/compositing/subtree_capture_id.mojom";
import "services/viz/public/mojom/compositing/surface_range.mojom";
import "services/viz/public/mojom/compositing/transferable_resource.mojom";
import "services/viz/public/mojom/compositing/view_transition_element_resource_id.mojom";
import "skia/public/mojom/blend_mode.mojom";
import "skia/public/mojom/skcolor4f.mojom";
import "skia/public/mojom/skpath.mojom";
import "ui/gfx/geometry/mojom/geometry.mojom";
import "ui/gfx/mojom/display_color_spaces.mojom";
import "ui/gfx/mojom/mask_filter_info.mojom";
import "ui/gfx/mojom/rrect_f.mojom";
import "ui/gfx/mojom/transform.mojom";

// Some properties on the Layer are rarely set, and so are bundled
// under a single optional field.
// NOTE: This struct's default values should be kept in sync with those of the
// C++-level RareProperties struct.
// TODO(crbug.com/408008599): Enforce this via struct_traits.
struct RareProperties {
  cc.mojom.FilterQuality filter_quality = cc.mojom.FilterQuality.kLow;

  // NOTE: Instances of this struct are initialized by reading the
  // corresponding instances of the C++-level struct, and thus no explicit
  // default value is needed here.
  cc.mojom.DynamicRangeLimit dynamic_range_limit;

  // The bounds of elements marked for potential region capture, stored in
  // the coordinate space of this layer.
  // NOTE: This field has no explicitly-set default value in the C++ struct.
  RegionCaptureBounds capture_bounds;
};

// Extra fields in a cc::MirrorLayerImpl that has been added to a tree or
// modified in some interesting way since a prior tree update.
struct MirrorLayerExtra {
  int32 mirrored_layer_id;
};

// Extra fields in a cc::SurfaceLayerImpl that has been added to a tree or
// modified in some interesting way since a prior tree update.
struct SurfaceLayerExtra {
  // This represents a range of surfaces the surface layer contains.
  SurfaceRange surface_range;

  // Number of frames to activation deadline.
  // If nullopt, use the default lower bound deadline instead.
  uint32? deadline_in_frames;

  // This flag indicates whether the surface layer stretches content to fill
  // bounds or not.
  bool stretch_content_to_fill_bounds;

  // This flag indicates whether the surface layer is hit testable or not.
  bool surface_hit_testable;

  // This flag indicates whether the surface layer has "pointer-events: none"
  // or not.
  bool has_pointer_events_none;

  // This flag indicates whether the surface layer is refelction or not.
  bool is_reflection;

  // This flag tracks if a visibility reset took place in the associated
  // SurfaceLayer and is used to update |will_draw_| on that layer accordingly.
  bool will_draw_needs_reset;

  // This flag indicates whether child paint flags (filter quality and
  // dynamic range limit) should be overridden or not.
  bool override_child_paint_flags;
};

// Extra fields in a cc::TextureLayerImpl that has been added to a tree or
// modified in some interesting way since a prior tree update.
struct TextureLayerExtra {
  bool blend_background_color;
  bool force_texture_to_opaque;
  gfx.mojom.PointF uv_top_left;
  gfx.mojom.PointF uv_bottom_right;
  bool update_transferable_resource;
  TransferableResource? transferable_resource;
};

// Extra fields in a cc::UIResourceLayerImpl that has been added to a tree or
// modified in some interesting way since a prior tree update.
struct UIResourceLayerExtra {
  cc.mojom.UIResourceId ui_resource_id;
  gfx.mojom.Size image_bounds;
  gfx.mojom.PointF uv_top_left;
  gfx.mojom.PointF uv_bottom_right;
};

// Extra fields in a cc::TileDisplayLayerImpl that has been added to a tree or
// modified in some interesting way since a prior tree update.
struct TileDisplayLayerExtra {
  // Optional field that will be set if this Layer is a PictureLayer that is
  // actually a solid color.
  skia.mojom.SkColor4f? solid_color;

  // Will be set to true for PictureLayers that are backdrop filter masks.
  bool is_backdrop_filter_mask;

  // Will be set to true for PictureLayers that are directly composited images.
  bool is_directly_composited_image;

  // Will be set to true for PictureLayers that use nearest neighbor filtering.
  bool nearest_neighbor;

  // Indicates whether the PictureLayer has an animated image update rect.
  bool has_animated_image_update_rect;

  // Indicates whether the PictureLayer has a non-animated image update rect.
  bool has_non_animated_image_update_rect;

  // The color usage of the layer's content.
  gfx.mojom.ContentColorUsage content_color_usage;

  // Valid rectangle in which anything is recorded and can be rastered from.
  // This is also used during AppendQuads to decide if a quad needs to be
  // drawn.
  gfx.mojom.Rect recorded_bounds;

  // Scales of tilings that the renderer proposes can be deleted.
  array<float> proposed_tiling_scales_for_deletion;
};

// Extra fields in a cc::ScrollbarLayerImplBase that has been added
// to a tree or modified in some interesting way since a prior tree update.
struct ScrollbarLayerBaseExtra {
  cc.mojom.ElementId scroll_element_id;
  bool is_overlay_scrollbar;
  bool is_web_test;
  float thumb_thickness_scale_factor;
  float current_pos;
  float clip_layer_length;
  float scroll_layer_length;
  bool is_horizontal_orientation;
  bool is_left_side_vertical_scrollbar;
  float vertical_adjust;
  bool has_find_in_page_tickmarks;
};

// Extra fields in a cc::NinePatchThumbScrollbarLayerImpl that has been added
// to a tree or modified in some interesting way since a prior tree update.
struct NinePatchThumbScrollbarLayerExtra {
  ScrollbarLayerBaseExtra scrollbar_base_extra;

  int32 thumb_thickness;
  int32 minimum_thumb_length;
  int32 track_start;
  int32 track_length;
  gfx.mojom.Size image_bounds;
  gfx.mojom.Rect aperture;
  cc.mojom.UIResourceId thumb_ui_resource_id;
  cc.mojom.UIResourceId track_and_buttons_ui_resource_id;
};

// Extra fields in a cc::PaintedScrollbarLayerImpl that has been added
// to a tree or modified in some interesting way since a prior tree update.
struct PaintedScrollbarLayerExtra {
  ScrollbarLayerBaseExtra scrollbar_base_extra;

  float internal_contents_scale;
  gfx.mojom.Size internal_content_bounds;
  bool jump_on_track_click;
  bool supports_drag_snap_back;
  int32 thumb_thickness;
  int32 minimum_thumb_length;
  gfx.mojom.Rect back_button_rect;
  gfx.mojom.Rect forward_button_rect;
  gfx.mojom.Rect track_rect;
  skia.mojom.SkColor4f? thumb_color;
  bool uses_nine_patch_track_and_buttons;
  gfx.mojom.Size track_and_buttons_image_bounds;
  gfx.mojom.Rect track_and_buttons_aperture;
  float painted_opacity;
  cc.mojom.UIResourceId track_and_buttons_ui_resource_id;
  cc.mojom.UIResourceId thumb_ui_resource_id;
};

// Extra fields in a cc::SolidColorScrollbarLayerImpl that has been added
// to a tree or modified in some interesting way since a prior tree update.
struct SolidColorScrollbarLayerExtra {
  ScrollbarLayerBaseExtra scrollbar_base_extra;

  int32 thumb_thickness;
  int32 track_start;
  skia.mojom.SkColor4f color;
};

// Extra fields in a cc::ViewTransitionContentLayerImpl that has been added
// to a tree or modified in some interesting way since a prior tree update.
struct ViewTransitionContentLayerExtra {
  // The corresponding element resource id to be drawn.
  ViewTransitionElementResourceId resource_id;

  // Live content layers that don't have a corresponding resource render
  // passes are skipped for drawing.
  bool is_live_content_layer;

  // max_extents_rect is the maximum possible size of the originating layer, as
  // known to blink, in the originating layer's coordinate space.
  gfx.mojom.RectF max_extents_rect;
};

// Extra fields in a cc::NinePatchLayerImpl that has been added to a tree or
// modified in some interesting way since a prior tree update.
struct NinePatchLayerExtra {
  // From NinePatchLayer quad_generator_ properties
  gfx.mojom.Rect image_aperture;
  gfx.mojom.Rect border;
  gfx.mojom.Rect layer_occlusion;
  bool fill_center;

  // From UIResourceLayer properties
  cc.mojom.UIResourceId ui_resource_id;
  gfx.mojom.Size image_bounds;
  gfx.mojom.PointF uv_top_left;
  gfx.mojom.PointF uv_bottom_right;
};

// Extra properties that are specific to a LayerImpl type.
union LayerExtra {
  // Extra properties that are specific to MirrorLayerImpl.
  MirrorLayerExtra mirror_layer_extra;
  // Extra properties that are specific to NinePatchThumbScrollbarLayerImpl.
  NinePatchThumbScrollbarLayerExtra nine_patch_thumb_scrollbar_layer_extra;
  // Extra properties that are specific to PaintedScrollbarLayerImpl.
  PaintedScrollbarLayerExtra painted_scrollbar_layer_extra;
  // Extra properties that are specific to SolidColorScrollbarLayerImpl.
  SolidColorScrollbarLayerExtra solid_color_scrollbar_layer_extra;
  // Extra properties that are specific to SurfaceLayerImpl.
  SurfaceLayerExtra surface_layer_extra;
  // Extra properties that are specific to TextureLayerImpl.
  TextureLayerExtra texture_layer_extra;
  // Extra properties that are specific to UIResourceLayerImpl.
  UIResourceLayerExtra ui_resource_layer_extra;
  // Extra properties that are specific to TileDisplayLayerImpl.
  TileDisplayLayerExtra tile_display_layer_extra;
  // Extra properties that are specific to ViewTransitionContentLayerImpl.
  ViewTransitionContentLayerExtra view_transition_content_layer_extra;
  // Extra properties that are specific to NinePatchLayerImpl.
  NinePatchLayerExtra nine_patch_layer_extra;
};

// General properties, common to all Layer types.
struct LayerGeneralProperties {
  // Bounds of the layer, generally in layer space. If this is the root layer,
  // bounds are in viewport space, including device scale factor.
  gfx.mojom.Size bounds;

  // Optimization hints indicating whether the layer is fully opaque, or at
  // least opaque wherever text is drawn.
  bool contents_opaque;
  bool contents_opaque_for_text;

  // Indicates whether the layer produces any visual output for the compositor.
  bool is_drawable;

  // Indicate that layer properties have changed and the layer's content area
  // needs to be redrawn.
  bool layer_property_changed_not_from_property_trees;
  bool layer_property_changed_from_property_trees;

  // Describes the opaqueness for hit testing in a layered content e.g. a layer.
  cc.mojom.HitTestOpaqueness hit_test_opaqueness;

  // The background color (and safe opaque background color) used by this Layer.
  // See comments for equivalent fields on cc::Layer.
  skia.mojom.SkColor4f background_color;
  skia.mojom.SkColor4f safe_opaque_background_color;

  // Optional stable identifier that may be referenced in property trees and
  // animations. Identifies a client-side object which can be represented by
  // multiple layers over time but only by a single layer at once.
  cc.mojom.ElementId element_id;

  // Current cumulative dirty rect for the layer since last update, in layer
  // space.
  gfx.mojom.Rect update_rect;

  // The post-transform position of this layer.
  gfx.mojom.Vector2dF offset_to_transform_parent;

  bool should_check_backface_visibility;

  RareProperties? rare_properties;

  // Extra properties that are specific to a layerImpl type.
  LayerExtra? layer_extra;
};

// Details about a cc::LayerImpl that has been added to a tree or modified in
// some interesting way since a prior tree update.
struct Layer {
  // The layer's assigned ID. This is an arbitrary integer value which is
  // guaranteed to be (a) unique across all layers currently in the tree and
  // (b) consistent for the lifetime of each layer. When a LayerTreeUpdate
  // contains a Layer with a previously unseen ID, the Layer is being added to
  // the tree; otherwise an existing layer's properties are changing.
  int64 id;

  // The type of this layer. If this structure is updating an existing layer,
  // the type here must match that of the existing layer.
  cc.mojom.LayerType type;

  // Property tree node IDs. Each of these IDs is bound to the range [0, N) for
  // a property tree with N nodes.
  int32 transform_tree_index;
  int32 clip_tree_index;
  int32 effect_tree_index;
  int32 scroll_tree_index;

  LayerGeneralProperties? general_properties;
};

// See blink::AnchorPositionScrollData, from which the fields here are derived.
struct AnchorPositionScrollData {
  array<cc.mojom.ElementId> adjustment_container_ids;
  gfx.mojom.Vector2d accumulated_scroll_origin;
  bool needs_scroll_adjustment_in_x;
  bool needs_scroll_adjustment_in_y;
};

// See blink::StickyPositionScrollingConstraints for documentation on this data.
struct StickyPositionNodeData {
  // At least one scroll ancestor must be a valid index into the scroll tree.
  int32 x_scroll_ancestor;
  int32 y_scroll_ancestor;

  // Additional fields derived from StickyPositionConstraint (which itself is
  // populated from StickyPositionScrollingConstraints).
  bool is_anchored_left;
  bool is_anchored_right;
  bool is_anchored_top;
  bool is_anchored_bottom;
  float left_offset;
  float right_offset;
  float top_offset;
  float bottom_offset;
  gfx.mojom.RectF constraint_box_rect;
  gfx.mojom.RectF scroll_container_relative_sticky_box_rect;
  gfx.mojom.RectF scroll_container_relative_containing_block_rect;
  gfx.mojom.Vector2dF pixel_snap_offset;
  int32 nearest_node_shifting_sticky_box;
  int32 nearest_node_shifting_containing_block;
  gfx.mojom.Vector2dF total_sticky_box_sticky_offset;
  gfx.mojom.Vector2dF total_containing_block_sticky_offset;
};

// Updates to a transform tree, not including the nodes themselves. These
// correspond to data members of cc::TransformTree.
struct TransformTreeUpdate {
  float page_scale_factor = 1.0;
  float device_scale_factor = 1.0;
  float device_transform_scale_factor = 1.0;
  array<int32> nodes_affected_by_outer_viewport_bounds_delta;
  array<int32> nodes_affected_by_safe_area_bottom;
  array<StickyPositionNodeData> sticky_position_data;
  array<AnchorPositionScrollData> anchor_position_scroll_data;
  map<cc.mojom.ElementId, gfx.mojom.Vector2dF> drawn_elastic_overscroll;
};

// Details about a new or updated node within a transform property tree.
struct TransformNode {
  // The ID of this node. Must be in the range [0, N) for a transform tree with
  // N nodes.
  int32 id;

  // The ID of the parent node. Must be in the range [0, N) for a transform tree
  // with N nodes, or -1 if this is the root node.
  int32 parent_id;

  // The ID of the nearest ancestor node in the tree which corresponds to the
  // root of a visible frame. Must be in the range [0, N) for a transform tree
  // with N nodes, or -1 if no ancestor is desginated as a frame root by the
  // client. May be the same as `id`.
  int32 parent_frame_id;

  // The stable ElementId of the client-side object to which this transform node
  // applies.
  cc.mojom.ElementId element_id;

  // Actual transformation parameters for this node. See cc::TransformNode.
  gfx.mojom.Transform local;
  gfx.mojom.Point3F origin;
  gfx.mojom.Vector2dF post_translation;
  gfx.mojom.Transform to_parent;
  gfx.mojom.PointF scroll_offset;
  gfx.mojom.Vector2dF snap_amount;

  // Optional index into the tree's sticky position constraint data.
  uint32? sticky_position_constraint_id;

  // Optional index into the tree's anchor position scroll data.
  uint32? anchor_position_scroll_data_id;

  // Arbitrary rendering context ID for sorting. This affects draw order within
  // the layer tree relative to other nodes with sorting context IDs. Does not
  // need to be validated.
  int32 sorting_context_id;

  // Flags reflecting client-side changes to transform state. These all
  // correspond to equivalent flags on cc::TransformNode.
  bool has_potential_animation;
  bool is_currently_animating;
  bool flattens_inherited_transform;
  bool scrolls;
  bool should_undo_overscroll;
  bool should_be_snapped;
  bool moved_by_outer_viewport_bounds_delta_y;
  bool in_subtree_of_page_scale_layer;
  bool transform_changed;
  bool delegates_to_parent_for_backface;
  bool will_change_transform;
  float maximum_animation_scale;
  bool node_and_ancestors_are_animated_or_invertible;
  bool is_invertible;
  bool ancestors_are_invertible;
  bool node_and_ancestors_are_flat;
  bool node_or_ancestors_will_change_transform;

  // The stable ElementId of the client-side object (e.g. document, in Blink)
  // corresponding to this node, if this node corresponds to the root of a
  // visible frame.
  cc.mojom.ElementId visible_frame_element_id;

  // cc::DamageReasonsSet bit mask tracking the damage reasons for changes to
  // this node.
  uint64 damage_reasons_bit_mask;

  // Used by the compositor to determine which layers need to be repositioned by
  // the compositor as a result of safe area inset bottom before Blink
  // repositions the fixed layers.
  bool moved_by_safe_area_bottom;
};

// Details about a new or updated node within a clip property tree.
struct ClipNode {
  // The ID of this node. Must be in the range [0, N) for a clip tree with N
  // nodes.
  int32 id;

  // The ID of the parent node. Must be in the range [0, N) for a clip tree with
  // N nodes, or -1 if this is the root node.
  int32 parent_id;

  // The ID of this clip node's corresponding transform node within the
  // transform tree. Must be in the range [0, N) for a transform tree with N
  // nodes.
  int32 transform_id;

  // The clip rectangle for this node, in the space of the corresponding
  // transform node.
  gfx.mojom.RectF clip;

  // The ID of this node's pixel-moving filter in the effect tree, or -1.
  int32 pixel_moving_filter_id;
};

// Details about a new or updated node within an effect property tree.
struct EffectNode {
  // The ID of this node. Must be in the range [0, N) for an effect tree with N
  // nodes.
  int32 id;

  // The ID of the parent node. Must be in the range [0, N) for an effect tree
  // with N nodes, or -1 if this is the root node.
  int32 parent_id;

  // The ID of this effect node's corresponding transform node within the
  // transform tree. Must be in the range [0, N) for a transform tree with N
  // nodes.
  int32 transform_id;

  // The ID of this effect node's corresponding clip node within the clip tree.
  // Must be in the range [0, N) for a clip tree with N nodes.
  int32 clip_id;

  // The stable ElementId of the client-side object to which this effect node
  // applies.
  cc.mojom.ElementId element_id;

  // The opacity of drawn layers associated with this effect node.
  float opacity;

  // RenderSurfaceReason::kNone if this effect node should not create a render
  // surface, or the reason that this effect node should create one.
  cc.mojom.RenderSurfaceReason render_surface_reason;

  // Scale applied to the contents of the render surface. Ignored if this node
  // doesn't induce a render surface.
  gfx.mojom.Vector2dF surface_contents_scale;

  SubtreeCaptureId subtree_capture_id;
  gfx.mojom.Size subtree_size;

  skia.mojom.BlendMode blend_mode;

  // The index of the ancestor EffectNode which induces a render surface. Must
  // be a valid index in the same effect tree.
  int32 target_id;

  // If this node is tagged with a ViewTransitionElementResourceId, it means it
  // produces a snapshot for an element participating in a transition. This
  // target id corresponds to the effect node where the
  // ViewTransitionContentLayer using this resource draws. Can be unset if no
  // layer using this resource is being drawn.
  int32 view_transition_target_id;

  // The ancestor ids indicate the existence of render surfaces, copy requests,
  // or captures on ancestor effect nodes.
  int32 closest_ancestor_with_cached_render_surface_id;
  int32 closest_ancestor_with_copy_request_id;
  int32 closest_ancestor_being_captured_id;
  int32 closest_ancestor_with_shared_element_id;

  // Represents a resource id for a resource cached or generated in the Viz
  // process.
  ViewTransitionElementResourceId view_transition_element_resource_id;

  FilterOperations filters;
  FilterOperations backdrop_filters;
  skia.mojom.SkPath? backdrop_filter_bounds;
  float backdrop_filter_quality = 1.0;

  // The element id corresponding to the mask to apply to the filtered backdrop
  // image.
  cc.mojom.ElementId backdrop_mask_element_id;

  // The mask filter information applied to this effect node. The coordinates of
  // in the mask info is in the space of the transform node associated with this
  // effect node.
  gfx.mojom.MaskFilterInfo mask_filter_info;

  bool cache_render_surface;
  // Whether the contents should continue to be visible when rotated such that
  // its back face is facing toward the camera. It's true by default.
  bool double_sided;
  bool trilinear_filtering;

  // TODO(crbug.com/40461368): Delete this after implementation of
  // SetHideLayerAndSubtree is cleaned up.
  bool subtree_hidden;
  // Whether this node has a potentially running (i.e., irrespective
  // of exact timeline) filter animation.
  bool has_potential_filter_animation;
  // Whether this node has a potentially running (i.e., irrespective
  // of exact timeline) backdrop-filter animation.
  bool has_potential_backdrop_filter_animation;
  // Whether this node has a potentially running (i.e., irrespective
  // of exact timeline) opacity animation.
  bool has_potential_opacity_animation;

  // Whether this node's effect has been changed since the last
  // frame. Needed in order to compute damage rect.
  bool effect_changed;

  // If set, the node's subtree has a copy request and the layer should
  // not be skipped for draw property computation.
  // TODO(crbug.com/406652614): Compute subtree_has_copy_request in
  // EffectTree::UpdateEffects() instead of serializing it.
  bool subtree_has_copy_request;

  // If set, the effect node tries to not trigger a render surface due to it
  // having a rounded corner.
  bool is_fast_rounded_corner;
  // True if a backdrop effect may be present on this effect (and therefore
  // any side-effects on ancestors should be taken into account).
  bool may_have_backdrop_effect;
  // Whether this effect is triggered by a non-identity 2D scale transform
  // (and no other transform).
  bool needs_effect_for_2d_scale_transform;

  // If true, the subtree rooted at this node only draws content that is visible
  // in the target surface.
  bool only_draws_visible_content;

  // The CopyOutputRequests that have been made for this node.
  array<CopyOutputRequest> copy_output_requests;
};

// Updates to a scroll tree, not including the nodes themselves. These
// correspond to data members of cc::ScrollTree.
struct ScrollTreeUpdate {
  map<cc.mojom.ElementId, cc.mojom.SyncedScrollOffset> synced_scroll_offsets;
  map<cc.mojom.ElementId, gfx.mojom.Rect> scrolling_contents_cull_rects;
  map<cc.mojom.ElementId, gfx.mojom.Vector2dF> elastic_overscroll;
};

// Details about a new or updated node within a scroll property tree.
struct ScrollNode {
  // The ID of this node. Must be in the range [0, N) for a scroll tree with N
  // nodes.
  int32 id;

  // The ID of the parent node. Must be in the range [0, N) for a scroll tree
  // with N nodes, or -1 if this is the root node.
  int32 parent_id;

  // The ID of this scroll node's corresponding transform node within the
  // transform tree. Must be in the range [0, N) for a transform tree with N
  // nodes.
  int32 transform_id;

  // The bounds of the scrollable container in which the scroll node's content
  // resides. This does not include non-overlay scrollbar footprint.
  gfx.mojom.Size container_bounds;

  // The size of the content scrolled within the node's scrollable container.
  gfx.mojom.Size bounds;

  // The stable ElementId of the scrollable client-side object to which this
  // scroll node applies.
  cc.mojom.ElementId element_id;

  // Flags specifying the behavior of scrolls on this node.
  bool max_scroll_offset_affected_by_page_scale;
  bool scrolls_inner_viewport;
  bool scrolls_outer_viewport;
  bool prevent_viewport_scrolling_from_inner;
  bool user_scrollable_horizontal;
  bool user_scrollable_vertical;
  bool is_composited;
};