/**
 * Runs once before the whole E2E suite. Two jobs:
 *
 *  1. Seed a known-good demo workspace deterministically, by shelling out to
 *     the same `backend/scripts/seed_demo.py --reset` a human would run —
 *     see that script's docstring for exactly what it creates (couple
 *     workspace, Alex/Sam/Nova, wishes, overrides, a few applied days).
 *
 *  2. Materialize one extra, deterministic multi-week band of planned leave
 *     days via the API (never by clicking through the UI) — the calendar
 *     only renders committed `planned_leave_day` rows, not raw wishes, and
 *     the seed script's own applied days are only 3 days long (too short to
 *     exercise cross-week-row banding). The band's dates are computed
 *     relative to "today", never hardcoded, and written to
 *     `e2e/.auth/fixture.json` for `calendar-band.spec.ts` to read.
 *
 * Defensive design: this polls the backend's health endpoint before doing
 * anything else, regardless of what order Playwright happens to start
 * `webServer` vs. `globalSetup` in — a setup failure here should always be
 * "the backend never came up", never a flaky race.
 */
import { mkdirSync, writeFileSync } from 'node:fs'
import path from 'node:path'
import { execFileSync } from 'node:child_process'
import { fileURLToPath } from 'node:url'
import { apiCreatePlannedDay, apiGetContext, apiLogin, DEMO_EMAIL, DEMO_PASSWORD, waitForBackendHealth } from './support/api'
import { FIXTURE_PATH } from './support/fixture'

const __dirname = path.dirname(fileURLToPath(import.meta.url))
const BACKEND_DIR = path.resolve(__dirname, '../../backend')

// A deterministic multi-week band, independent of the leave-wish allocation
// engine's own date choices: 15 consecutive WEEKDAYS (~3 calendar-week
// rows), starting on the 1st of the month that is two months after
// "today" — always safely in the future, always entirely inside one
// calendar month (so the Calendar page shows both the band's true start and
// true end in a single month view), and never tied to a hardcoded year.
function computeBandDates(): { startDate: string; endDate: string; dates: string[] } {
  const now = new Date()
  const monthStart = new Date(Date.UTC(now.getUTCFullYear(), now.getUTCMonth() + 2, 1))
  const dates: string[] = []
  const cursor = new Date(monthStart.getTime())
  while (dates.length < 15) {
    const weekday = cursor.getUTCDay()
    if (weekday !== 0 && weekday !== 6) {
      dates.push(cursor.toISOString().slice(0, 10))
    }
    cursor.setUTCDate(cursor.getUTCDate() + 1)
  }
  const first = dates[0]
  const last = dates[dates.length - 1]
  if (!first || !last) throw new Error('failed to compute band dates')
  return { startDate: first, endDate: last, dates }
}

export default async function globalSetup(): Promise<void> {
  await waitForBackendHealth()

  execFileSync('uv', ['run', 'python', 'scripts/seed_demo.py', '--reset'], {
    cwd: BACKEND_DIR,
    stdio: 'inherit',
  })

  const token = await apiLogin(DEMO_EMAIL, DEMO_PASSWORD)
  const context = await apiGetContext(token)
  const child = context.children[0]
  if (!child) {
    throw new Error('seed_demo.py did not create a child for the demo workspace')
  }

  const band = computeBandDates()
  for (const date of band.dates) {
    await apiCreatePlannedDay(token, {
      workspace_id: context.workspace_id,
      child_id: child.id,
      parent_personal_data_uuid: context.personal_data_uuid,
      date,
      day_type: 'vacation',
      is_dubbeldag: false,
    })
  }

  mkdirSync(path.dirname(FIXTURE_PATH), { recursive: true })
  writeFileSync(
    FIXTURE_PATH,
    JSON.stringify(
      {
        workspaceId: context.workspace_id,
        childId: child.id,
        personalDataUuid: context.personal_data_uuid,
        childBirthDate: child.birth_date,
        band: {
          startDate: band.startDate,
          endDate: band.endDate,
          parentPersonalDataUuid: context.personal_data_uuid,
          dayType: 'vacation',
        },
      },
      null,
      2,
    ),
  )
}