// A real server F for the editor's browser tests: bundled as the build
// bundles it (dist/main.mjs and its room thread), started as a process with
// a throwaway Postgres (packages/server/test/database.ts), on the host the
// editor's page comes from, so that F's cookie goes with the page's
// requests. A project is made in F's store straight from a FILIUS file; a
// person signs in as the dashboard would let them, with a ticket at /__auth.
// Given a built editor, F hands it out itself, as in the image: then the
// editor's page comes from F's own origin.

import { spawn, type ChildProcess } from 'node:child_process';
import { mkdtempSync, readFileSync } from 'node:fs';
import { tmpdir } from 'node:os';
import { join } from 'node:path';
import { randomUUID } from 'node:crypto';
import type { BrowserContext } from '@playwright/test';
import { build } from 'esbuild';
import pg from 'pg';
import * as Y from 'yjs';
import { writeProject } from '@mdg-filius/doc';
import { openProjectArchive } from '@mdg-filius/fls';
import { testDatabase, type TestDatabase } from '../../server/test/database.js';
import { signTicket } from '../../server/test/tickets.js';

const TICKET_SECRET = 'browser-ticket-secret';
export const SERVICE_KEY = 'browser-service-key';

export interface ServerF {
  readonly base: string;
  /** A project made from a FILIUS file of the corpus; its devices' ids by name. */
  project(file: string): Promise<{ readonly id: string; readonly node: (name: string) => string }>;
  /** Signs a person in, in this browser context. */
  signIn(context: BrowserContext, project: string, person: { readonly name: string; readonly level?: 'read' | 'write'; readonly user?: string }): Promise<void>;
  service(method: string, path: string, body?: unknown): Promise<Response>;
  /** The size of a blob in F's store, none without it. */
  blobSize(sha: string): Promise<number | undefined>;
  /** How many updates of a project F has stored since it last compacted it. */
  updateCount(project: string): Promise<number>;
  close(): Promise<void>;
}

/** Server F on the editor page's host (`editorBase`), for pages from there, or from itself with `editorFolder`. */
export async function startServerF(editorBase: string, editorFolder?: string): Promise<ServerF> {
  const editor = new URL(editorBase);
  const database: TestDatabase = await testDatabase();
  const out = mkdtempSync(join(tmpdir(), 'filius-server-f-'));
  const source = new URL('../../server/src/', import.meta.url).pathname;
  await build({
    entryPoints: [join(source, 'main.ts'), join(source, 'simWorker.ts')],
    bundle: true,
    platform: 'node',
    format: 'esm',
    target: 'node20',
    outdir: out,
    outExtension: { '.js': '.mjs' },
    external: ['pg-native'],
    banner: { js: "import { createRequire as createBundleRequire } from 'node:module'; const require = createBundleRequire(import.meta.url);" },
    logLevel: 'error',
  });
  const port = 20_000 + Math.floor(Math.random() * 20_000);
  const base = `${editor.protocol}//${editor.hostname}:${port}`;
  const child: ChildProcess = spawn(process.execPath, [join(out, 'main.mjs')], {
    env: {
      ...process.env,
      DATABASE_URL: database.url,
      FILIUS_TICKET_SECRET: TICKET_SECRET,
      FILIUS_SERVICE_KEY: SERVICE_KEY,
      FILIUS_ORIGINS: editorFolder === undefined ? editor.origin : base,
      ...(editorFolder === undefined ? {} : { FILIUS_EDITOR_DIR: editorFolder }),
      FILIUS_PORT: String(port),
      FILIUS_INSECURE_COOKIE: '1',
    },
    stdio: ['ignore', 'pipe', 'inherit'],
  });
  await new Promise<void>((resolve, reject) => {
    child.stdout!.on('data', (data: Buffer) => {
      if (data.toString().includes('"server.listening"')) resolve();
    });
    child.once('exit', (code) => reject(new Error(`server F ended (${code})`)));
  });
  const sql = new pg.Pool({ connectionString: database.url });
  return {
    base,
    async project(file) {
      const id = randomUUID();
      const imported = openProjectArchive(new Uint8Array(readFileSync(new URL(`../../../corpus/${file}`, import.meta.url))), () => randomUUID());
      const doc = new Y.Doc();
      writeProject(doc, imported);
      await sql.query('INSERT INTO filius_doc (project_uuid, state) VALUES ($1, $2)', [id, Buffer.from(Y.encodeStateAsUpdate(doc))]);
      return { id, node: (name) => imported.graph.nodes.find((each) => each.displayName === name)!.id };
    },
    async signIn(context, project, { name, level = 'write', user = randomUUID() }) {
      const ticket = signTicket({ u: user, n: name.toLowerCase(), d: name, p: project, lvl: level }, TICKET_SECRET);
      const page = await context.newPage();
      const response = await page.goto(`${base}/__auth?ticket=${encodeURIComponent(ticket)}&next=/healthz`);
      if (response?.status() !== 200) throw new Error(`not signed in: ${response?.status()}`);
      await page.close();
    },
    async blobSize(sha) {
      const result = await sql.query<{ size: number }>('SELECT size FROM filius_blob WHERE sha = $1', [sha]);
      return result.rows[0]?.size;
    },
    async updateCount(project) {
      const result = await sql.query<{ count: string }>('SELECT count(*) FROM filius_doc_update WHERE project_uuid = $1', [project]);
      return Number(result.rows[0]!.count);
    },
    service: (method, path, body) => fetch(`${base}${path}`, { method, headers: { 'x-filius-service-key': SERVICE_KEY }, ...(body === undefined ? {} : { body: JSON.stringify(body) }) }),
    async close() {
      const ended = new Promise((resolve) => child.once('exit', resolve));
      child.kill('SIGTERM');
      await ended;
      await sql.end();
      await database.stop();
    },
  };
}