import { execSync } from 'node:child_process'
import { writeFileSync } from 'node:fs'
import { dirname, resolve } from 'node:path'
import { fileURLToPath } from 'node:url'

const __dirname = dirname(fileURLToPath(import.meta.url))
const API_HOST = process.env.E2E_API_URL || 'http://localhost:8100'
const API_BASE = `${API_HOST}/api/v1`
const COMPOSE_FILE = resolve(__dirname, '../../docker-compose.test.yml')
const COMPOSE = `docker compose -p nuzlocke-test -f ${COMPOSE_FILE}`
const FIXTURES_PATH = resolve(__dirname, '.fixtures.json')

function run(cmd: string): string {
  console.log(`[setup] ${cmd}`)
  return execSync(cmd, { encoding: 'utf-8', stdio: ['pipe', 'pipe', 'inherit'] })
}

async function waitForApi(url: string, maxAttempts = 30): Promise<void> {
  for (let i = 0; i < maxAttempts; i++) {
    try {
      const res = await fetch(url)
      if (res.ok) return
    } catch {
      // not ready yet
    }
    await new Promise((r) => setTimeout(r, 2000))
  }
  throw new Error(`API at ${url} not ready after ${maxAttempts} attempts`)
}

async function api<T>(
  path: string,
  options?: RequestInit,
): Promise<T> {
  const res = await fetch(`${API_BASE}${path}`, {
    headers: { 'Content-Type': 'application/json' },
    ...options,
  })
  if (!res.ok) {
    const body = await res.text()
    throw new Error(`API ${options?.method ?? 'GET'} ${path} → ${res.status}: ${body}`)
  }
  return res.json() as Promise<T>
}

export default async function globalSetup() {
  // 1. Start test DB + API
  run(`${COMPOSE} up -d --build`)

  // 2. Wait for API to be healthy
  console.log('[setup] Waiting for API to be ready...')
  await waitForApi(`${API_HOST}/`)

  // 3. Run migrations
  run(`${COMPOSE} exec -T test-api alembic -c /app/alembic.ini upgrade head`)

  // 4. Seed reference data (run from /app/src where the app package lives)
  run(`${COMPOSE} exec -T -w /app/src test-api python -m app.seeds`)

  // 5. Create test fixtures via API
  const games = await api<Array<{ id: number; name: string }>>('/games')
  const game = games[0]
  if (!game) throw new Error('No games found after seeding')

  const routes = await api<Array<{ id: number; name: string; parentRouteId: number | null }>>(
    `/games/${game.id}/routes?flat=true`,
  )
  // Pick leaf routes (no children — a route is a leaf if no other route has it as parent)
  const parentIds = new Set(routes.map((r) => r.parentRouteId).filter(Boolean))
  const leafRoutes = routes.filter((r) => !parentIds.has(r.id))
  if (leafRoutes.length < 3) throw new Error(`Need ≥3 leaf routes, found ${leafRoutes.length}`)

  const pokemonRes = await api<{ items: Array<{ id: number; name: string }> }>(
    '/pokemon?limit=10',
  )
  const pokemon = pokemonRes.items
  if (pokemon.length < 3) throw new Error(`Need ≥3 pokemon, found ${pokemon.length}`)

  // Create a test run
  const testRun = await api<{ id: number }>('/runs', {
    method: 'POST',
    body: JSON.stringify({
      gameId: game.id,
      name: 'E2E Test Run',
      rules: { duplicatesClause: true, shinyClause: true },
    }),
  })

  // Create encounters: caught, fainted, missed
  const statuses = ['caught', 'fainted', 'missed'] as const
  for (let i = 0; i < 3; i++) {
    await api(`/runs/${testRun.id}/encounters`, {
      method: 'POST',
      body: JSON.stringify({
        routeId: leafRoutes[i]!.id,
        pokemonId: pokemon[i]!.id,
        nickname: `Test ${statuses[i]}`,
        status: statuses[i],
        catchLevel: statuses[i] === 'missed' ? null : 5 + i * 10,
      }),
    })
  }

  // Create a genlocke with 2 game legs
  const secondGame = games[1] ?? game
  const genlocke = await api<{ id: number }>('/genlockes', {
    method: 'POST',
    body: JSON.stringify({
      name: 'E2E Test Genlocke',
      gameIds: [game.id, secondGame.id],
      genlockeRules: {},
      nuzlockeRules: { duplicatesClause: true },
    }),
  })

  // 6. Write fixtures file
  const fixtures = {
    gameId: game.id,
    runId: testRun.id,
    genlockeId: genlocke.id,
  }
  writeFileSync(FIXTURES_PATH, JSON.stringify(fixtures, null, 2))
  console.log('[setup] Fixtures written:', fixtures)
}