ttrpg-tools/src/components/journal/registry.ts

127 lines
4.3 KiB
TypeScript

/**
* Journal Stream — Message Type Registry
*
* An open, add-only registry of message types. Game-specific widgets
* call `registerMessageType()` at module import time. The stream core
* uses this to validate, render, and reduce messages.
*/
import type { ZodType } from "zod";
import type { JSX } from "solid-js";
// ---------------------------------------------------------------------------
// StreamMessage
// ---------------------------------------------------------------------------
/**
* The typed envelope carried on the stream topic.
* `P` is narrowed by the `type` key at the receiving side.
*/
export interface StreamMessage<P = unknown> {
/** Deterministic id: `{sender}-{seq}` */
id: string;
/** Sender identifier — "gm" or a player name */
sender: string;
/** Monotonic sequence number, per sender */
seq: number;
/** Registered type key — determines which payload schema & widget are used */
type: string;
/** Type-specific data, validated against the registry's Zod schema */
payload: P;
/** Epoch millis, set by the sender at publish time */
timestamp: number;
/**
* Soft-delete. Only the sender's latest (highest seq) message can be
* reverted. Sending a new message locks the previous one permanently.
*/
reverted: boolean;
}
// ---------------------------------------------------------------------------
// MessageTypeDef
// ---------------------------------------------------------------------------
export interface MessageTypeDef<P = unknown> {
/** Unique type key, e.g. "roll.request", "article.reveal" */
type: string;
/** Human-readable label shown in the compose panel dropdown */
label: string;
/** Which roles can emit this type. Empty array = all roles allowed. */
emitters?: ("gm" | "player")[];
/** Zod schema used to validate payload before publish */
schema: ZodType<P>;
/** Returns a default payload for compose panel initialization */
defaultPayload?: () => P;
/**
* Render the message body in the stream.
* Receives the full message for context (sender, timestamp, reverted).
* Return undefined to suppress inline rendering (e.g. pure state mutations).
*/
render?: (payload: P, msg: StreamMessage<P>) => JSX.Element | undefined;
/**
* Apply side-effects to local state when this message is received.
* Runs once per message, at initial hydration and on live receipt.
*/
reducer?: (payload: P, msg: StreamMessage<P>) => void;
}
// ---------------------------------------------------------------------------
// Registry
// ---------------------------------------------------------------------------
const registry = new Map<string, MessageTypeDef<any>>();
/**
* Register a message type. Calling module should import and call this at
* top-level so the registry is populated before any stream operations.
*/
export function registerMessageType<P>(def: MessageTypeDef<P>): void {
if (registry.has(def.type)) {
throw new Error(`Message type "${def.type}" is already registered.`);
}
registry.set(def.type, def);
}
/** Retrieve a registered type definition. */
export function getMessageType(type: string): MessageTypeDef | undefined {
return registry.get(type);
}
/** Iterate over all registered type keys. */
export function registeredTypes(): IterableIterator<string> {
return registry.keys();
}
/**
* Validate a payload against the registered schema for `type`.
* Returns the parsed (narrowed) payload on success, or a ZodError.
*/
export function validatePayload<P>(
type: string,
payload: P,
): { success: true; data: P } | { success: false; error: string } {
const def = registry.get(type);
if (!def) {
return { success: false, error: `Unknown message type: "${type}"` };
}
const result = def.schema.safeParse(payload);
if (result.success) {
return { success: true, data: result.data as P };
}
return {
success: false,
error: result.error.issues.map((i) => `${i.path.join(".")}: ${i.message}`).join("; "),
};
}
/**
* Check whether a role (sender) is allowed to emit a given message type.
*/
export function canEmit(type: string, role: string): boolean {
const def = registry.get(type);
if (!def) return false;
const emitters = def.emitters;
if (!emitters || emitters.length === 0) return true;
return emitters.includes(role as "gm" | "player");
}