import { afterEach, describe, expect, it, vi } from 'vitest'
import { createMemoryDb, runMigrations, repos } from '@evofw/db'
import { buildApp } from '../../app.js'
import { loadConfig } from '../../config.js'
import { hashToken } from '../../plugins/auth.js'
import { evaluateAgentPolicy } from './evaluate.js'
import { policyCacheFor } from './cache.js'
import { refreshAllHostnameRules } from './resolve-hostname.js'

const dns = vi.hoisted(() => ({ resolve4: vi.fn(), resolve6: vi.fn(), cancel: vi.fn() }))
vi.mock('node:dns/promises', async (original) => ({ ...await original<typeof import('node:dns/promises')>(), Resolver: class { resolve4 = dns.resolve4; resolve6 = dns.resolve6; cancel = dns.cancel } }))
const opened: ReturnType<typeof createMemoryDb>[] = []
const apps: Awaited<ReturnType<typeof buildApp>>[] = []
afterEach(async () => { for (const app of apps.splice(0)) await app.close(); for (const mem of opened.splice(0)) mem.sqlite.close(); vi.resetAllMocks() })
function memory() {
  const mem = createMemoryDb(); opened.push(mem); runMigrations(mem.sqlite)
  repos.insertAgent(mem.db, { id: 'a', name: 'a', tokenPrefix: 'a', tokenHash: 'a', status: 'approved' })
  return mem
}
function hostnameFixture() {
  const mem = memory(); repos.ensureSharedSetAssigned(mem.db, 'a')
  for (const [id, hostname, cidr, priority] of [['h1', 'first.test', '192.0.2.1/32', 10], ['h2', 'second.test', '192.0.2.2/32', 20]] as const) {
    repos.insertPolicyRule(mem.db, { id, setId: 'set-shared-default', hostname, action: 'deny', priority })
    repos.replaceResolvedForRule(mem.db, id, [cidr])
  }
  dns.resolve6.mockResolvedValue([])
  return mem
}

describe('cache assignment and DNS publication invalidation', () => {
  it('refreshes cached preview set names after a rename without bumping again for an identical name', async () => {
    const app = await buildApp({ memory: true, config: { ...loadConfig(), authRequired: false, staticDir: null, logLevel: 'error' } }); apps.push(app); await app.ready()
    repos.insertAgent(app.db, { id: 'a', name: 'a', tokenPrefix: 'a', tokenHash: 'a', status: 'approved' })
    repos.ensureSharedSetAssigned(app.db, 'a')
    repos.insertPolicyRule(app.db, { id: 'deny', setId: 'set-shared-default', action: 'deny', cidr: '10.0.0.0/8', priority: 10 })
    const before = (await app.inject({ url: '/api/v1/agents/a/preview' })).json()
    const renamed = await app.inject({ method: 'PATCH', url: '/api/v1/policy-sets/set-shared-default', payload: { name: 'Renamed source set' } })
    expect(renamed.statusCode).toBe(200)
    const after = (await app.inject({ url: '/api/v1/agents/a/preview' })).json()
    expect(after.chain[0].set_name).toBe('Renamed source set')
    expect(after.generation).toBe(before.generation + 1)
    expect(after.hash).toBe(before.hash)
    await app.inject({ method: 'PATCH', url: '/api/v1/policy-sets/set-shared-default', payload: { name: 'Renamed source set' } })
    expect((await app.inject({ url: '/api/v1/agents/a/preview' })).json().generation).toBe(after.generation)
  })

  it('invalidates a preview cached before single and bulk approval, with exactly one insertion bump and idempotent retries', async () => {
    const app = await buildApp({ memory: true, config: { ...loadConfig(), authRequired: false, staticDir: null, logLevel: 'error' } }); apps.push(app); await app.ready()
    repos.insertPolicyRule(app.db, { id: 'deny', setId: 'set-shared-default', action: 'deny', cidr: '10.0.0.0/8', priority: 10 })
    for (const id of ['single', 'bulk']) {
      repos.insertAgent(app.db, { id, name: id, tokenPrefix: id, tokenHash: hashToken(`token-${id}`), status: 'pending' })
      const preview = await app.inject({ url: `/api/v1/agents/${id}/preview` })
      expect(preview.statusCode).toBe(200)
      expect(preview.json().summary.cidrs_deny).toBe(0)
      expect(preview.json().generation).toBe(1)
    }
    const single = await app.inject({ method: 'POST', url: '/api/v1/agents/single/approve' })
    expect(single.statusCode).toBe(200)
    expect(single.json().policy_generation).toBe(2)
    const bulk = await app.inject({ method: 'POST', url: '/api/v1/agents/approve-bulk', payload: { agent_ids: ['bulk'] } })
    expect(bulk.statusCode).toBe(200)
    expect(bulk.json().items[0].policy_generation).toBe(2)
    for (const id of ['single', 'bulk']) {
      const policy = await app.inject({ url: '/v1/agent/policy', headers: { authorization: `Bearer token-${id}` } })
      expect(policy.statusCode).toBe(200)
      expect(policy.json()).toMatchObject({ generation: 2, deny_cidrs: ['10.0.0.0/8'] })
      expect(repos.ensureSharedSetAssigned(app.db, id)).toBe(false)
      expect(repos.getAgent(app.db, id)!.policyGeneration).toBe(2)
    }
    expect((await app.inject({ method: 'POST', url: '/api/v1/agents/single/approve' })).json().policy_generation).toBe(2)
    expect((await app.inject({ method: 'POST', url: '/api/v1/agents/approve-bulk', payload: { agent_ids: ['bulk'] } })).json().items).toEqual([])
    expect(repos.getAgent(app.db, 'bulk')!.policyGeneration).toBe(2)
  })

  it('rolls back assignment insertion when the generation bump fails, and existing assignments never bump again', () => {
    const mem = memory()
    mem.sqlite.exec("CREATE TRIGGER reject_generation BEFORE UPDATE OF policy_generation ON agents BEGIN SELECT RAISE(ABORT,'test generation failure'); END")
    expect(() => repos.ensureSharedSetAssigned(mem.db, 'a')).toThrow(/generation failure/)
    expect(repos.listSetsForAgent(mem.db, 'a')).toEqual([])
    expect(repos.getAgent(mem.db, 'a')!.policyGeneration).toBe(1)
    mem.sqlite.exec('DROP TRIGGER reject_generation')
    expect(repos.ensureSharedSetAssigned(mem.db, 'a')).toBe(true)
    expect(repos.ensureSharedSetAssigned(mem.db, 'a')).toBe(false)
    expect(repos.getAgent(mem.db, 'a')!.policyGeneration).toBe(2)
  })

  it('keeps warm and cold previews on the old snapshot while another DNS lookup is pending, then publishes once atomically', async () => {
    const mem = hostnameFixture()
    const before = evaluateAgentPolicy(mem.db, 'a')
    let release!: (value: string[]) => void
    const second = new Promise<string[]>((resolve) => { release = resolve })
    dns.resolve4.mockImplementation((host) => host === 'second.test' ? second : Promise.resolve(['203.0.113.1']))
    const refresh = refreshAllHostnameRules(mem.db)
    await vi.waitFor(() => expect(dns.resolve4).toHaveBeenCalledWith('second.test'))
    expect(repos.listResolvedForRule(mem.db, 'h1').map((row) => row.cidr)).toEqual(['192.0.2.1/32'])
    expect(evaluateAgentPolicy(mem.db, 'a')).toBe(before)
    policyCacheFor(mem.db).get('a', 'force-cold-preview', Date.now())
    expect(evaluateAgentPolicy(mem.db, 'a').hash).toBe(before.hash)
    release(['203.0.113.2']); await refresh
    const after = evaluateAgentPolicy(mem.db, 'a')
    expect(after.denyCidrs).toEqual(['203.0.113.1/32', '203.0.113.2/32'])
    expect(after.generation).toBe(before.generation + 1)
    await refreshAllHostnameRules(mem.db)
    expect(evaluateAgentPolicy(mem.db, 'a')).toBe(after)
  })

  it('preserves failed lookup snapshots and never overwrites a newer publication made while DNS was pending', async () => {
    const mem = hostnameFixture()
    let reject!: (reason: Error) => void
    const second = new Promise<string[]>((_, fail) => { reject = fail })
    dns.resolve4.mockImplementation((host) => host === 'second.test' ? second : Promise.resolve(['203.0.113.1']))
    const refresh = refreshAllHostnameRules(mem.db)
    await vi.waitFor(() => expect(dns.resolve4).toHaveBeenCalledWith('second.test'))
    repos.replaceResolvedForRule(mem.db, 'h1', ['198.51.100.1/32'])
    repos.bumpAgentsForSet(mem.db, 'set-shared-default')
    const newer = evaluateAgentPolicy(mem.db, 'a')
    reject(Object.assign(new Error('timeout'), { code: 'ETIMEOUT' })); await refresh
    expect(evaluateAgentPolicy(mem.db, 'a')).toBe(newer)
    expect(newer.denyCidrs).toEqual(['192.0.2.2/32', '198.51.100.1/32'])
  })
})