import { mkdir, rm, stat, writeFile } from 'node:fs/promises';
import { join } from 'node:path';
import { db } from 'officerdb/db';
import { fofosAdminSettings } from '../db/schema';
import { readDatabases } from './databases';
import { backupAfterPublish, defaultBackupDir } from './backups';
import { buildSite } from './static-site';

/**
 * Publish: copy the site's content from development to production, then build.
 *
 * ── Why this exists ──
 *
 * The admin edits development and the build renders production, so nothing written in the panel could
 * reach the live site. Build was only half of publishing. Without this the first symptom is a
 * successful build of yesterday's content, which reads as a broken build and sends somebody looking at
 * the renderer.
 *
 * Copy and build are ONE action rather than two buttons in an order nobody is told. A copy without a
 * build changes nothing anybody can see, and a build without a copy is the bug above.
 *
 * ── What is copied, and what is deliberately not ──
 *
 * Every table the site owns EXCEPT two:
 *
 *   `users`               — accounts and password hashes. Production's logins are not development's,
 *                           and overwriting them would lock somebody out of the live site in order to
 *                           publish a photograph.
 *   `contact_submissions` — the legacy inbox. Messages live in SQLite now and this table is only what
 *                           predates that. Development's copy is empty, so copying it over production
 *                           would destroy real messages to publish nothing — the most expensive thing
 *                           this file could possibly do.
 *
 * The list is explicit rather than "every table except". A table added later should be considered
 * rather than swept along, and the failure mode of the other choice — production-only data silently
 * overwritten by an empty development table — is discovered far too late to fix.
 */

/** The site's content. Parents before children, so the restore satisfies its own foreign keys. */
const CONTENT_TABLES = [
  'home_content',
  'home_gallery_media',
  'about_content',
  'galleries',
  'gallery_items',
  'collections',
  'collection_items',
  'collection_item_media',
  'gallery_pieces',
  'gallery_piece_media',
  'drops',
  'drop_media',
  'collabs',
  'collab_media',
  'service_nodes',
  'partners',
  'social_links',
  'contact_details',
] as const;

/** Long enough for a slow dump of a few megabytes, short enough that a wedged psql is not forever. */
const TIMEOUT_MS = 5 * 60 * 1000;

/**
 * Connection details as ENVIRONMENT, not as a URL argument.
 *
 * `libpq` reads these, so the password never appears in `ps` or in anything that logs a command line.
 * The database name is the one part passed as an argument, because it is the part that is not secret
 * and the part that changes between the two calls.
 */
const connection = (): Record<string, string> => {
  const raw = process.env.OFFICERDEV_POSTGRES_URL ?? process.env.POSTGRES_URL;
  if (!raw) throw new Error('The platform has no Postgres connection configured.');
  const url = new URL(raw);
  return {
    PGHOST: url.hostname,
    PGPORT: url.port || '5432',
    PGUSER: decodeURIComponent(url.username),
    PGPASSWORD: decodeURIComponent(url.password),
  };
};

const run = async (argv: string[], env: Record<string, string>) => {
  const proc = Bun.spawn(argv, {
    stdout: 'pipe',
    stderr: 'pipe',
    stdin: 'ignore',
    env: { ...process.env, ...env },
  });
  const timer = setTimeout(() => proc.kill(), TIMEOUT_MS);
  try {
    const [stdout, stderr, code] = await Promise.all([
      new Response(proc.stdout).text(),
      new Response(proc.stderr).text(),
      proc.exited,
    ]);
    return { ok: code === 0, output: `${stdout}${stderr}`.trim() };
  } finally {
    clearTimeout(timer);
  }
};

export type PublishResult = { ok: boolean; output: string };

export async function publish(secrets: Parameters<typeof buildSite>[0]): Promise<PublishResult> {
  const row = (await db.select().from(fofosAdminSettings).limit(1))[0] ?? null;
  const status = await readDatabases();
  const production = status.production.name;
  const development = status.development.name;

  if (!production || !status.production.exists) throw new Error('The production database does not exist.');
  if (!development || !status.development.exists) throw new Error('The development database does not exist.');

  const env = connection();
  const dir = row?.backupDir ?? defaultBackupDir();
  await mkdir(dir, { recursive: true });
  const stamp = new Date().toISOString().replace(/[-:]/g, '').replace(/\..+$/, '').replace('T', '-');
  const lines: string[] = [];

  /*
    ── 1. A way back, before anything is destroyed ──

    This truncates and replaces. A dump taken immediately before is the difference between a mistake
    that costs a minute and one that costs everything the client has written, and the whole database is
    a few megabytes. If it cannot be taken, nothing else happens.
  */
  const safety = join(dir, `${production}-before-publish-${stamp}.sql`);
  const dumped = await run(['pg_dump', '-f', safety, production], env);
  if (!dumped.ok) {
    return { ok: false, output: `Refusing to publish: production could not be backed up first.\n${dumped.output}` };
  }
  lines.push(`backed up production → ${safety}`);

  /*
    ── 2. Read development BEFORE clearing production ──

    Ordered this way on purpose. Dumping second would mean a failure to read development leaves
    production already empty — the site down, for a reason that had nothing to do with production. Now
    the worst a bad dump can do is stop before touching anything.
  */
  const staged = join(dir, `.publish-${stamp}.sql`);
  const dumpArgs = CONTENT_TABLES.flatMap((table) => ['--table', table]);
  const copy = await run(['pg_dump', '--data-only', ...dumpArgs, '-f', staged, development], env);
  if (!copy.ok) {
    await rm(staged, { force: true });
    return { ok: false, output: `${lines.join('\n')}\nCould not read development: ${copy.output}` };
  }
  const size = (await stat(staged).catch(() => null))?.size ?? 0;
  lines.push(`read ${CONTENT_TABLES.length} tables from ${development} (${size} bytes)`);

  /*
    ── 3. Clear and load, as ONE transaction ──

    Written as a wrapper around the dump rather than as two psql calls, and that shape is the whole
    point of this step:

    `-1` puts the truncate and the load in one transaction, and TRUNCATE is transactional in Postgres.
    So a load that fails takes the truncate down with it and production keeps the content it had.
    Two separate calls — which is what this was first — leave the live site EMPTY when the second one
    fails, for however long it takes somebody to notice and restore. Verified against a scratch copy of
    production: a deliberately failing load left all nine rows in place.

    `session_replication_role = replica` turns off foreign-key checks for the session. `pg_dump` warns
    that `service_nodes` carries a circular foreign key and that a --data-only dump of it may not
    restore; today the rows happen to come out parents-first and it loads either way, but "happens to"
    is not a property to depend on for the live site. It needs superuser, and if it is refused the
    transaction rolls back like any other failure — production intact, the reason in the output.

    `RESTART IDENTITY`, so the sequence values the dump then sets are not merely ahead of the rows it
    inserts. A copy whose sequences still start at 1 does not fail here; it fails on the client's next
    save, hours later, somewhere else entirely.
  */
  const wrapper = join(dir, `.publish-${stamp}.psql`);
  await writeFile(
    wrapper,
    [
      'SET session_replication_role = replica;',
      `TRUNCATE ${CONTENT_TABLES.join(', ')} RESTART IDENTITY CASCADE;`,
      `\\i ${staged}`,
      '',
    ].join('\n'),
  );

  try {
    const loaded = await run(['psql', '-1', '-q', '-v', 'ON_ERROR_STOP=1', '-f', wrapper, production], env);
    if (!loaded.ok) {
      return {
        ok: false,
        output: `${lines.join('\n')}\nThe copy failed and was rolled back — production still holds the content it had.\n\n${loaded.output}`,
      };
    }
    lines.push('copied development content into production');
  } finally {
    await rm(staged, { force: true });
    await rm(wrapper, { force: true });
  }

  // ── 4. Render it ──
  const built = await buildSite(secrets);
  lines.push(built.output);
  if (!built.ok) return { ok: false, output: lines.join('\n') };

  /*
    The configured backup, if "on publish" is what it is set to.

    `backupAfterPublish` decides that for itself and swallows its own failures, so this calls it
    unconditionally: a backup that could not be taken must not turn into a publish that appears to have
    failed, when the thing the person asked for actually worked.
  */
  await backupAfterPublish();

  return { ok: true, output: lines.join('\n') };
}