/**
 * Applies scripts/migrations/*.sql in name order, once each, inside one
 * transaction. Applied names are recorded in schema_migration.
 *
 *   bun scripts/migrate.ts            apply pending migrations
 *   bun scripts/migrate.ts --status   list applied and pending migrations
 *
 * Every migration is additive and idempotent, so a database that was set up
 * with drizzle-kit push or the old migrate-platform script is safe to run.
 */
import { SQL } from 'bun';
import { readdir, readFile } from 'node:fs/promises';

const databaseUrl = process.env.DB_URL || process.env.DATABASE_URL;
if (!databaseUrl) throw new Error('DB_URL or DATABASE_URL is required');

const directory = new URL('./migrations/', import.meta.url);
const files = (await readdir(directory)).filter((name) => name.endsWith('.sql')).sort();
const sql = new SQL(databaseUrl, { max: 1 });

try {
	await sql`CREATE TABLE IF NOT EXISTS schema_migration (name text PRIMARY KEY, applied_at timestamptz NOT NULL DEFAULT now())`;
	const applied = new Set(
		((await sql`SELECT name FROM schema_migration`) as { name: string }[]).map((row) => row.name)
	);
	const pending = files.filter((name) => !applied.has(name));

	if (process.argv.includes('--status')) {
		for (const name of files) console.log(`${applied.has(name) ? 'applied' : 'pending'}  ${name}`);
	} else if (pending.length === 0) {
		console.log('Database is up to date');
	} else {
		await sql.begin(async (tx) => {
			for (const name of pending) {
				await tx.unsafe(await readFile(new URL(name, directory), 'utf8'));
				await tx`INSERT INTO schema_migration (name) VALUES (${name})`;
				console.log(`applied  ${name}`);
			}
			// The root administrator is configured per environment, never guessed.
			const rootId = process.env.ROOT_ADMIN_USER_ID;
			const legacyRoot = process.env.ROOT_ADMIN_EMAIL;
			if (rootId)
				await tx`UPDATE "user" SET root_admin = true, role = 'admin' WHERE id = ${rootId}`;
			else if (legacyRoot)
				await tx`UPDATE "user" SET root_admin = true, role = 'admin' WHERE lower(email) = ${legacyRoot.toLowerCase()}`;
		});
		console.log(`${pending.length} migration(s) applied atomically`);
	}
} finally {
	await sql.end();
}