import { dirname, join } from 'node:path'
import { fileURLToPath } from 'node:url'
import { readFileSync, readdirSync, mkdirSync } from 'node:fs'
import Database from 'better-sqlite3'
import { drizzle } from 'drizzle-orm/better-sqlite3'
import { schema } from './schema.js'

export type Sqlite = Database.Database
export type Db = ReturnType<typeof drizzle<typeof schema>>

const __dirname = dirname(fileURLToPath(import.meta.url))

export function resolveDatabasePath(databaseUrl: string): string {
  const url = databaseUrl.startsWith('sqlite:')
    ? databaseUrl.slice('sqlite:'.length)
    : databaseUrl
  return url
}

export function createDb(databaseUrl: string): { db: Db; sqlite: Sqlite } {
  const path = resolveDatabasePath(databaseUrl)
  const dir = dirname(path)
  if (dir && dir !== '.') {
    try {
      mkdirSync(dir, { recursive: true })
    } catch {
      /* exists */
    }
  }
  const sqlite = new Database(path)
  sqlite.pragma('journal_mode = WAL')
  sqlite.pragma('synchronous = NORMAL')
  sqlite.pragma('foreign_keys = ON')
  const db = drizzle(sqlite, { schema })
  return { db, sqlite }
}

export function createMemoryDb(): { db: Db; sqlite: Sqlite } {
  const sqlite = new Database(':memory:')
  sqlite.pragma('foreign_keys = ON')
  const db = drizzle(sqlite, { schema })
  return { db, sqlite }
}

export function runMigrations(sqlite: Sqlite): void {
  const migrationsDir = join(__dirname, '..', 'migrations')
  const files = readdirSync(migrationsDir)
    .filter((f) => f.endsWith('.sql'))
    .sort()

  sqlite.exec(
    `CREATE TABLE IF NOT EXISTS _migrations (
      id INTEGER PRIMARY KEY AUTOINCREMENT,
      name TEXT NOT NULL UNIQUE,
      applied_at TEXT NOT NULL DEFAULT (datetime('now'))
    )`,
  )

  for (const file of files) {
    const applied = sqlite
      .prepare('SELECT 1 FROM _migrations WHERE name = ?')
      .get(file)
    if (applied) continue

    const sql = readFileSync(join(migrationsDir, file), 'utf-8')
    sqlite.exec(sql)
    sqlite.prepare('INSERT INTO _migrations (name) VALUES (?)').run(file)
  }
}

export function healthCheck(sqlite: Sqlite): void {
  sqlite.prepare('SELECT 1').get()
}