// ── window.__rg — the shared-dependency global ─────────────────────────────
//
// Phase 2, PR 7 of docs/website/MODULE_SYSTEM.md §2.7; the normative shape is
// docs/website/MODULE_API.md §3.2.
//
// A module's client half is a PREBUILT ESM chunk — the operator never builds
// anything (MODULE_SYSTEM.md §1.14) — served same-origin and loaded under
// `script-src 'self'` with no 'unsafe-inline'. That combination is what rules out
// an import map: an import map has to be an inline `<script type="importmap">`,
// and the policy forbids inline scripts outright. So the shared dependencies ride
// on a global, and the module's Rollup externals are aliased to two-line shims
// that re-export from it (§3.6).
//
// **There is exactly one React in the page and core owns it.** A module that
// bundled its own would get a second hook dispatcher and fail at its first
// useState. That is the same rule the server half enforces for `express` and
// `express-validator` on `ctx`, and for the same reason: anything shared between
// core and a module is owned by core and HANDED OVER, never resolved by the
// module.

import * as react from 'react'
import * as reactDom from 'react-dom/client'
import * as router from 'react-router-dom'
// The automatic JSX runtime, and it is not decoration. A module's bundler
// compiles every .jsx file to imports from `react/jsx-runtime` under the modern
// default, and those have to resolve to CORE's React like every other import.
// Without it here a module would have to build with `jsxRuntime: 'classic'`;
// with it, a module uses the default its tooling already assumes.
import * as jsxRuntime from 'react/jsx-runtime'

import { registry } from './registry.js'
import { MODULE_API_VERSION } from './version.js'

import PublicLayout from '../components/PublicLayout.jsx'
import PageHeader from '../components/PageHeader.jsx'
import { Loading, ErrorState, EmptyState } from '../components/PageState.jsx'
import { useAsync } from '../lib/useAsync.js'
import { useAuth } from '../contexts/AuthContext.jsx'
import { useSite } from '../contexts/SiteContext.jsx'
import { request, ApiError, BASE } from '../api/client.js'

// The UI kit is CURATED AND CLOSED (§3.4), not a re-export of components/. These
// eight exports — five table rows in §3.4, since `PageState` contributes three —
// are what the smallest UO page already needs beyond React and the router:
// without them a module either reaches into core's tree — violating the
// zero-import rule the whole boundary rests on — or ships its own copies, which
// means a module page that does not look like the site it is installed in, and
// that drifts further every time core's layout changes.
//
// Adding a member is a MINOR MODULE_API_VERSION bump; changing a member's props
// is a MAJOR one. That is a real constraint on core's own refactoring and it is
// the price of the boundary being worth anything.
//
// `AdminPage` was in an early draft of §3.4's table and is deliberately absent:
// core has no such component — admin views are plain markup inside AdminLayout —
// and inventing one to satisfy a table would be a core change with no consumer
// until Phase 3. The contract was amended rather than the code padded (it no
// longer lists it), and adding it later costs a minor bump, which is exactly the
// case the versioning is for.
const ui = {
  PublicLayout,
  PageHeader,
  Loading,
  ErrorState,
  EmptyState,
  useAsync,
  useAuth,
  useSite,
}

// The request PRIMITIVE, not the `api` object (§3.5): a module builds its own
// namespace over `request` and owns the paths it calls, which is right, because
// it owns the routes at the other end.
//
// `BASE` was in §3.5 from the start and missing from this object until slice 3,
// which is when something first needed it. `request` is fetch-only, so an
// EventSource — the shard's live feed is two of them — has to build its own URL,
// and the alternative is a module hardcoding `/api/v1`: an assertion about where
// core mounts its API that core has never promised to keep.
const api = { request, ApiError, BASE }

/**
 * Publish `window.__rg`. Called by main.jsx before it renders, and before any
 * module chunk evaluates.
 *
 * Frozen, one level down as well as at the top: the object a module reaches for
 * its React is not somewhere a module gets to leave something for the next one.
 * Cross-module communication is a thing the contract does not have, and an
 * unfrozen global is how a codebase acquires one by accident.
 */
export function publishSharedDependencies() {
  window.__rg = Object.freeze({
    version: MODULE_API_VERSION,
    react,
    reactDom,
    router,
    jsxRuntime,
    registry,
    ui: Object.freeze(ui),
    api: Object.freeze(api),
  })
  return window.__rg
}
