hello-tsubaki

// SPDX-License-Identifier: MPL-2.0

// Authoring surface for an "actor": a small xpi whose page side is a
// JSWindowActor (the same shape as Firefox's own about:newtab add-on). Each
// actor lives in one file that exports three things by name:
//
//   export const meta    = { id, namespace, matches, ... };
//   export const parent  = defineParent({ method(...) { ... } });  // main process (JSWindowActorParent)
//   export const content = defineContent((parent, ctx) => { ... }); // page side (run by JSWindowActorChild)
//
// The page side is NOT a WebExtension content script: content scripts are not
// injected into about:* / chrome:* documents in stock Firefox (see README,
// "addon 式が駄目だった理由"). The child actor loads content.js into the page's
// process with `window` / `document` on the scope chain, so the hook is written
// the same way, but it runs with the child actor's privileges.
//
// Named exports (rather than one nested object) are deliberate: the build
// bundles `parent` and `content` into separate outputs, and named exports let
// the bundler tree-shake each side so the content bundle never drags in the
// parent's privileged code and vice versa.
//
// IMPORTANT: the module top level must be pure. Reference Firefox globals
// (Services, ChromeUtils, window, exportFunction, browser) only *inside* method
// or hook bodies — the build imports this file under Deno to read `meta`, and
// top-level use of those globals would throw there.

export interface ActorMeta {
  /** Extension id, e.g. "settings-bridge@noraneko.app". */
  id: string;
  /** Extension version. */
  version: string;
  /** Experiment-API namespace, e.g. "noraSettings". Also the message channel. */
  namespace: string;
  /** Match patterns for the pages the content hook runs in (JSWindowActor `matches`). */
  matches: string[];
  /**
   * When the content hook runs. Maps to a child actor event:
   * document_start → DOMDocElementInserted, document_end → DOMContentLoaded,
   * document_idle → load. Defaults to "document_end".
   */
  runAt?: "document_start" | "document_end" | "document_idle";
  /**
   * JSWindowActor name. Defaults to "Nora" + PascalCase(<dir>), e.g. NoraNewtab.
   * A drop with the same actor name replaces the built-in one (unregister → register).
   */
  actor?: string;
  /** Legacy JSActor (BrowserGlue) this one replaces; it is unregistered when this actor is registered. */
  replaces?: string;
}

import type { Io } from "./io.ts";

type ParentMethods = Record<string, (...args: any[]) => unknown>;

export interface ContentCtx {
  /** True in dev builds (import.meta.env.MODE === "dev"). */
  dev: boolean;
  /** Expose functions on the page window (via exportFunction). */
  expose(funcs: Record<string, (...args: any[]) => unknown>): void;
  /**
   * Run when this actor goes away in this window (the drop is removed or
   * replaced). Put back what the hook changed: DOM, observers, listeners.
   */
  onDestroy(fn: () => void): void;
  /**
   * Place things through these (DOM, styles, listeners, pref observers) and
   * they are taken out again by themselves: each verb puts its way back on
   * the same ledger as onDestroy.
   */
  io: Io;
  /** This actor's own files: `${ctx.base}ops/x.tsubaki` and the like. */
  base: string;
  /**
   * The actor's logic in Tsubaki (when it ships wasm/): run a .tsubaki file of
   * its own with load("ops/x.tsubaki"), then call(name, ...args). Values cross
   * as ordinary JS values; a Tsubaki error is a JS Error. undefined without wasm/.
   *
   * Every verb answers with a Promise, because for an actor of the browser
   * WINDOW the logic lives a process away (wasm can't compile in the parent
   * process, so it runs in a hidden page of this window instead). A drop never
   * has to know which side it got.
   */
  ops: Ops | undefined;
}

export interface Ops {
  ready: Promise<void>;
  call(name: string, ...args: unknown[]): Promise<unknown>;
}

/** Proxy to the parent methods; each call is forwarded to the main process. */
type ParentProxy<T extends ParentMethods> = {
  [K in keyof T]: (...args: Parameters<T[K]>) => Promise<Awaited<ReturnType<T[K]>>>;
};

export type ContentHook<T extends ParentMethods = ParentMethods> = (
  parent: ParentProxy<T>,
  ctx: ContentCtx,
) => void;

// Identity helpers that pin types for authoring:
//
//   export const parent  = defineParent({ method(...) { ... } });
//   export const content = defineContent<typeof parent>((parent, ctx) => { ... });
//
// They are listed in the build's treeshake.manualPureFunctions, so an unused
// call (e.g. defineContent in the parent bundle) is dropped along with anything
// it references (birpc). Without that, the bundler would keep the call for its
// possible side effects and the unused side would not tree-shake.

/** Pins the parent-method types so the content hook's proxy is typed. */
export const defineParent = <T extends ParentMethods>(methods: T): T => methods;

/** Pins the content hook against the parent's method types. */
export const defineContent = <T extends ParentMethods>(
  hook: ContentHook<T>,
): ContentHook<T> => hook;

// SPDX-License-Identifier: MPL-2.0
// GENERATED by build.ts. この drop の actor は Tsubaki で書かれている:
// 直すのは ops/main.tsubaki と drop.toml の [actor]。
//
// 殻は lib の std-actor。logic が答える三つの door(setup / start / dispatch)
// を呼んで、返ってきた view を描き、effects を carry out する。殻の bytes は
// その lib に一枚だけあって、ここには入らない(この drop に残るのは、下の宣言だけ)。

import { defineContent, defineParent, type ActorMeta } from "../_shared/defineActor.ts";
import { runTsubakiActor } from "std-actor";

export const meta: ActorMeta = {
  "id": "hello-tsubaki@noraneko.app",
  "version": "1.2.0",
  "namespace": "noraHelloTsubaki",
  "matches": [
    "chrome://browser/content/browser.xhtml"
  ],
  "runAt": "document_end"
};

export const parent = defineParent({});

export const content = defineContent<typeof parent>((_parent, ctx) => {
  runTsubakiActor(ctx, {"prefs":["noraneko.hello.count"],"keys":[],"commands":[],"browserPages":[],"menus":[],"tabs":"","tabMarks":false,"tabValues":false,"windowValues":false,"prompt":false,"currentUrl":false,"openUrl":false,"webFrame":false,"chromeStyle":true,"ownPrefix":"noraneko.hello-tsubaki.","name":"hello-tsubaki","uuid":"1da7ff69-3500-4bdc-b838-029dfce35a34","strings":{}}).catch((e) =>
    console.error("[hello] failed:", e)
  );
});

# SPDX-License-Identifier: MPL-2.0
#
# actor まで Tsubaki で書いた drop。この file と drop.toml の [actor] のほかには、
# 何も無い(JS は一行も書いていない。build が、どの drop でも同じ殻を着せる)。
#
# 殻が訊いてくるのは三つ:
#
#   setup()           どこに置くか、style、見ていてほしい pref
#   start(facts)      最初の一枚(facts = もう本当だったこと。prefs と url)
#   dispatch(action)  次の一枚と、してほしいこと
#
# VNode / frame / SetPref は std のことば(std-tsubaki-runtime の ops/std.tsubaki)。

PREF = "noraneko.hello.count"

setup() = Dict(
    "anchor" => Dict("at" => "parent", "selector" => "#nav-bar", "tag" => "hbox", "id" => "nora-hello"),
    "style" => "#nora-hello { flex: 0 0 auto; align-items: center; margin-inline: 6px; } #nora-hello label { white-space: nowrap; padding: 2px 8px; border-radius: 6px; background: color-mix(in srgb, currentColor 12%, transparent); }",
    "prefs" => [PREF]
)

@kwdef struct AppState
    count = 0
end

STATE = AppState()

# --- view ---------------------------------------------------------------------

# ツールバーの toolbarbutton は label を隠すので、素の XUL の label に置いた
view(s) = el("label", Dict(
    "value" => "hello " * string(s.count),
    "tooltiptext" => PREF,
    "on:click" => Bump()
))

# --- actions ------------------------------------------------------------------

struct Bump end

"about:config で数を書き換えられたとき、殻が投げてくる"
struct PrefChanged
    name
    value
end

action_of(a) = begin
    kind = get(a, :__type, "")
    if kind == "Bump"
        Bump()
    elseif kind == "PrefChanged"
        PrefChanged(get(a, :name, ""), get(a, :value, 0))
    else
        error("hello: no action named " * kind)
    end
end

# --- update -------------------------------------------------------------------

update(s::AppState, a::Bump) = begin
    n = s.count + 1
    Step(AppState(count = n), [SetPref(PREF, n)])
end

update(s::AppState, a::PrefChanged) = begin
    n = a.value === nothing ? 0 : a.value
    Step(AppState(count = n), [])
end

struct Step
    state
    effects
end

# --- the doors ----------------------------------------------------------------

function start(facts)
    prefs = get(facts, :prefs, Dict())
    held = get(prefs, PREF, 0)
    STATE = AppState(count = held === nothing ? 0 : held)
    return frame(view(STATE))
end

function dispatch(a)
    st = update(STATE, action_of(a))
    STATE = st.state
    return frame(view(STATE), st.effects)
end