import { readdir, readFile } from 'node:fs/promises'
import { dirname, resolve } from 'node:path'
import { fileURLToPath } from 'node:url'
import { PGlite } from '@electric-sql/pglite'
import { Pool } from 'pg'

const __dirname = dirname(fileURLToPath(import.meta.url))
const migrationsDir = resolve(__dirname, '../src/migrations')

function createSchemaName() {
  return `ca_test_${Date.now()}_${Math.random().toString(16).slice(2)}`
}

export async function createTestDb() {
  const postgresUrl = process.env.CA_STUDIO_TEST_DATABASE_URL
  const migrationFiles = (await readdir(migrationsDir))
    .filter((file) => file.endsWith('.sql'))
    .sort()
  const migrationSql = await Promise.all(
    migrationFiles.map(async (file) => readFile(resolve(migrationsDir, file), 'utf8'))
  )

  if (postgresUrl) {
    const schema = createSchemaName()
    const bootstrapPool = new Pool({ connectionString: postgresUrl })
    await bootstrapPool.query(`CREATE SCHEMA "${schema}"`)
    await bootstrapPool.end()

    const pool = new Pool({
      connectionString: postgresUrl,
      options: `-c search_path=${schema},public`,
      allowExitOnIdle: true
    })
    for (const sql of migrationSql) {
      await pool.query(sql)
    }
    return pool
  }

  const db = new PGlite()
  for (const sql of migrationSql) {
    await db.exec(sql)
  }
  return db
}