import { test } from 'node:test'
import assert from 'node:assert/strict'
import { EventEmitter } from 'node:events'

import { RunController } from '../src/controller.mjs'

function fakeOrchestrator(config, { status = 'running' } = {}) {
  const runState = new EventEmitter()
  runState.state = { status, runId: config.runId }
  const orchestrator = {
    config,
    state: runState,
    run: async () => ({ status: 'done', runId: config.runId }),
    requestStop: () => true,
    submitAnswers: () => true,
    listCheckpointMeta: () => [{ id: 'iter-01' }],
    revertIteration: () => ({ ok: true }),
  }
  return orchestrator
}

function makeController() {
  const created = []
  const baseConfig = { project: '/repo', goal: '', goalText: '', iterations: 5, agent: 'code-design', hitl: 'on-question' }
  const controller = new RunController(baseConfig, {
    createOrchestrator: (config) => {
      const orch = fakeOrchestrator(config, { status: 'running' })
      created.push(orch)
      return orch
    },
  })
  return { controller, created, baseConfig }
}

test('snapshot reports idle before any run', () => {
  const { controller } = makeController()
  const snap = controller.snapshot()
  assert.equal(snap.idle, true)
  assert.equal(snap.status, 'idle')
  assert.equal(controller.isActive(), false)
})

test('start merges per-run overrides into the config', async () => {
  const { controller, created } = makeController()
  await controller.start({ goal: 'goal.json', verify: 'pnpm test', iterations: 3, agent: 'code', dryRun: true })
  assert.equal(created.length, 1)
  const config = created[0].config
  assert.equal(config.goal, 'goal.json')
  assert.equal(config.verify, 'pnpm test')
  assert.equal(config.iterations, 3)
  assert.equal(config.agent, 'code')
  assert.equal(config.dryRun, true)
  assert.ok(config.runId)
})

test('start applies a per-run custom instruction (promptExtra) override', async () => {
  const { controller, created } = makeController()
  await controller.start({ goal: 'goal.json', promptExtra: 'focus on the parser only' })
  assert.equal(created[0].config.promptExtra, 'focus on the parser only')
})

test('start leaves the base custom instruction when the override is omitted', async () => {
  const controller = new RunController(
    { project: '/repo', goal: '', iterations: 5, agent: 'code-design', promptExtra: 'base instructions' },
    { createOrchestrator: (config) => fakeOrchestrator(config, { status: 'running' }) },
  )
  await controller.start({ goal: 'goal.json' })
  assert.equal(controller.config.promptExtra, 'base instructions')
})

test('start refuses while a run is active', () => {
  const { controller } = makeController()
  controller.start({ goal: 'goal.json' })
  assert.equal(controller.isActive(), true)
  assert.throws(() => controller.start({ goal: 'other.json' }), /already active/)
})

test('start requires a goal', () => {
  const { controller } = makeController()
  assert.throws(() => controller.start({}), /goal is required/)
})

test('control methods delegate to the attached orchestrator', () => {
  const { controller, created } = makeController()
  controller.start({ goal: 'goal.json' })
  assert.equal(controller.requestStop(), true)
  assert.equal(controller.submitAnswers([]), true)
  assert.deepEqual(controller.listCheckpointMeta(), [{ id: 'iter-01' }])
  assert.deepEqual(controller.revertIteration(1), { ok: true })
  assert.equal(created.length, 1)
})

test('control methods are safe with no orchestrator', () => {
  const { controller } = makeController()
  assert.equal(controller.requestStop(), false)
  assert.equal(controller.submitAnswers([]), false)
  assert.deepEqual(controller.listCheckpointMeta(), [])
  assert.equal(controller.revertIteration(1).ok, false)
})

test('attach adopts an existing orchestrator and forwards its events', () => {
  const { controller } = makeController()
  const orch = fakeOrchestrator({ runId: 'adopted' }, { status: 'running' })
  let states = 0
  controller.on('state', () => (states += 1))
  controller.attach(orch)
  assert.equal(controller.orchestrator, orch)
  assert.equal(states >= 1, true)
  orch.state.emit('update')
  assert.equal(states >= 2, true)
})