import { existsSync, mkdtempSync, rmSync, writeFileSync } from 'node:fs'
import { tmpdir } from 'node:os'
import { join } from 'node:path'
import Database from 'better-sqlite3'
import { afterEach, describe, expect, it } from 'vitest'
import {
  backupDatabase,
  checkIntegrity,
  closeDb,
  createDb,
  createUser,
  getUserByEmail,
  listBackups,
  migrateSchema,
} from '../src/index.js'

const dirs: string[] = []
const dbs: Array<ReturnType<typeof createDb>['sqlite']> = []
afterEach(() => {
  for (const s of dbs.splice(0)) closeDb(s)
  for (const d of dirs.splice(0)) rmSync(d, { recursive: true, force: true })
})

function fileDb() {
  const dir = mkdtempSync(join(tmpdir(), 'ap-bk-'))
  dirs.push(dir)
  const r = createDb(join(dir, 'app.db'))
  migrateSchema(r.sqlite)
  dbs.push(r.sqlite)
  return { dir, ...r }
}

describe('backupDatabase', () => {
  it('создаёт консистентную копию с данными из WAL', async () => {
    const { dir, db, sqlite } = fileDb()
    createUser(db, { email: 'a@x.io', name: 'A', passwordHash: 'h', isAdmin: false })
    const res = await backupDatabase(sqlite, { dir: join(dir, 'backups'), keep: 3 })
    expect(existsSync(res.file)).toBe(true)
    expect(checkIntegrity(res.file)).toBe(true)

    const copy = new Database(res.file, { readonly: true })
    const row = copy.prepare('SELECT email FROM users').get()
    copy.close()
    expect(row).toEqual({ email: 'a@x.io' })
  })

  it('бэкап во время записи остаётся валидным', async () => {
    const { dir, db, sqlite } = fileDb()
    const writer = setInterval(() => {
      try {
        createUser(db, {
          email: `u${Math.random()}@x.io`,
          name: 'U',
          passwordHash: 'h',
          isAdmin: false,
        })
      } catch {
        /* БД могла закрыться */
      }
    }, 1)
    const res = await backupDatabase(sqlite, { dir, keep: 3 })
    clearInterval(writer)
    expect(checkIntegrity(res.file)).toBe(true)
  })

  it('ротация оставляет keep последних', async () => {
    const { dir, sqlite } = fileDb()
    const bdir = join(dir, 'b')
    for (let i = 0; i < 5; i++) {
      await backupDatabase(sqlite, {
        dir: bdir,
        keep: 2,
        now: new Date(Date.UTC(2026, 0, 1, 0, 0, i)),
      })
    }
    const left = listBackups(bdir)
    expect(left).toHaveLength(2)
    expect(left[0]).toContain('000004')
  })

  it('восстановленная копия открывается и содержит данные', async () => {
    const { dir, db, sqlite } = fileDb()
    createUser(db, { email: 'r@x.io', name: 'R', passwordHash: 'h', isAdmin: false })
    const res = await backupDatabase(sqlite, { dir, keep: 1 })
    const restored = createDb(res.file)
    dbs.push(restored.sqlite)
    migrateSchema(restored.sqlite)
    expect(getUserByEmail(restored.db, 'r@x.io')?.name).toBe('R')
  })

  it('битый файл не проходит integrity_check', () => {
    const dir = mkdtempSync(join(tmpdir(), 'ap-bad-'))
    dirs.push(dir)
    const p = join(dir, 'bad.db')
    writeFileSync(p, 'not a sqlite file'.repeat(100))
    expect(() => checkIntegrity(p)).toThrow()
  })

  it('ошибка бэкапа не оставляет .partial', async () => {
    const { dir, sqlite } = fileDb()
    closeDb(sqlite)
    await expect(backupDatabase(sqlite, { dir: join(dir, 'x'), keep: 1 })).rejects.toThrow()
    expect(listBackups(join(dir, 'x'))).toHaveLength(0)
  })
})