feuerwerk/src/core/model/Asset.ts

import type { Graph } from '../graph/Graph';
import type { PropertyDef } from '../properties/PropertySchema';
import type { AssetType } from './AssetTypes';
import type { PropertyBag } from './Properties';
import type { Scope } from './Scope';
import type { SceneObject } from './SceneObject';

export interface AssetBase {
  id: string;
  type: AssetType;
  name: string;
  props: PropertyBag;
}

export interface SpriteAsset extends AssetBase {
  type: 'sprite';
}

export interface CameraAsset extends AssetBase {
  type: 'camera';
}

export interface TextAsset extends AssetBase {
  type: 'text';
}

export interface SceneAsset extends AssetBase {
  type: 'scene';
  objects: SceneObject[];
}

/** `variables` is this asset's own property schema; `props` holds their default values. */
export interface BehaviorAsset extends AssetBase {
  type: 'behavior';
  variables: PropertyDef[];
  graph: Graph;
}

/** Placed as a child of the object it belongs to; its position is the offset from that body. */
export interface ColliderAsset extends AssetBase {
  type: 'collider';
}

/**
 * `objects` is a template, not content: a placed container shows it without copying it, so an
 * edit here reaches every instance (see `model/instance.ts`). Positions are local to the
 * container's origin.
 */
export interface ContainerAsset extends AssetBase {
  type: 'container';
  objects: SceneObject[];
}

/** `id` shares the generator with asset ids and is unique across the document (see `model/texture.ts`). */
export interface TextureFrame {
  id: string;
  name: string;
  x: number;
  y: number;
  w: number;
  h: number;
}

/**
 * `file` names the image in `data/textures/` and is content-addressed (`{sha256}.{ext}`), so it
 * can be cached forever; empty means the upload failed or has not happened yet. `width`/`height`
 * are the size as uploaded, so frames can be sliced and validated before the image loads.
 */
export interface TextureAsset extends AssetBase {
  type: 'texture';
  file: string;
  width: number;
  height: number;
  frames: TextureFrame[];
}

/**
 * `frames` holds what a sprite's `texture` holds – a texture id or a frame id – in playing order.
 * A picture may appear more than once, which is how one frame is held longer.
 */
export interface AnimationAsset extends AssetBase {
  type: 'animation';
  frames: string[];
}

/**
 * The graph holds one `State` node per state and an edge per transition; a behavior reads the
 * machine's current state through `State branch` and moves it through `Set state` or `State transition`.
 * A `global` machine has one current state for the whole run instead of one per behavior instance.
 */
export interface StateMachineAsset extends AssetBase {
  type: 'statemachine';
  graph: Graph;
  scope?: Scope;
}

/**
 * The graph is GLSL in nodes: `Property` nodes declare the sprite rows, the `Output` node ends
 * the fragment (see `core/shader/compile.ts`). A sprite wears it through its `shader` property.
 */
export interface ShaderAsset extends AssetBase {
  type: 'shader';
  graph: Graph;
}

/**
 * `file` names the typeface in `data/fonts/` the way a texture names its image: content-addressed
 * `{sha256}.{ext}`, empty when the upload failed. A text object wears it through its `font`
 * property; the family the browser knows it under is derived from the file name, see `model/font`.
 */
export interface FontAsset extends AssetBase {
  type: 'font';
  file: string;
}

/**
 * The graph is the motion of one particle: every output of its `Output` node is a function of the
 * particle's age and its own random number (see `core/particles/compile.ts`). A placed object is
 * the source that emits them; how many and for how long are its properties.
 */
export interface ParticlesAsset extends AssetBase {
  type: 'particles';
  graph: Graph;
}

export type Asset =
  | SpriteAsset
  | CameraAsset
  | TextAsset
  | SceneAsset
  | BehaviorAsset
  | ColliderAsset
  | ContainerAsset
  | TextureAsset
  | AnimationAsset
  | StateMachineAsset
  | ShaderAsset
  | FontAsset
  | ParticlesAsset;

/** The assets edited as a node graph – what the graph canvas and the graph commands work on. */
export type GraphAsset = BehaviorAsset | StateMachineAsset | ShaderAsset | ParticlesAsset;

const GRAPH_TYPES: ReadonlySet<AssetType> = new Set(['behavior', 'statemachine', 'shader', 'particles']);

export function isGraphAsset(asset: Asset): asset is GraphAsset {
  return GRAPH_TYPES.has(asset.type);
}

export function isSceneAsset(asset: Asset): asset is SceneAsset {
  return asset.type === 'scene';
}