import { readFile } from "fs/promises";
import postgres from "postgres";

const migrationTag = "0011_unique_submission_user";
const migrationPath = "drizzle/0011_unique_submission_user.sql";

const databaseUrl = process.env.DATABASE_URL;
if (!databaseUrl) {
  throw new Error("DATABASE_URL is not set");
}

const sql = postgres(databaseUrl, { max: 1 });

try {
  const duplicates = await sql<{ form_id: string; user_discord_id: string; count: string }[]>`
    select form_id, user_discord_id, count(*)::text as count
    from form.submission
    where user_discord_id is not null
    group by form_id, user_discord_id
    having count(*) > 1
    limit 20
  `;

  if (duplicates.length > 0) {
    console.error("Duplicate submissions would violate the unique index:");
    for (const duplicate of duplicates) {
      console.error(
        `form_id=${duplicate.form_id} user_discord_id=${duplicate.user_discord_id} count=${duplicate.count}`
      );
    }
    process.exit(1);
  }

  await sql`
    create unique index if not exists "submission_form_user_discord_id_unique"
    on "form"."submission" using btree ("form_id", "user_discord_id")
  `;

  const migrationTable = await sql<{ exists: boolean }[]>`
    select to_regclass('drizzle.__drizzle_migrations') is not null as exists
  `;

  if (migrationTable[0]?.exists) {
    const existing = await sql<{ count: string }[]>`
      select count(*)::text as count
      from drizzle.__drizzle_migrations
      where hash = ${migrationTag}
    `;

    if (existing[0]?.count === "0") {
      const migrationSql = await readFile(migrationPath, "utf8");
      await sql`
        insert into drizzle.__drizzle_migrations (hash, created_at)
        values (${migrationTag}, ${Date.now()})
      `;
      console.log(`Applied ${migrationTag}: ${migrationSql.trim()}`);
    } else {
      console.log(`${migrationTag} was already recorded.`);
    }
  } else {
    console.log("Applied index. Drizzle migration table was not found, so no migration row was recorded.");
  }
} finally {
  await sql.end();
}