import { randomUUID } from 'node:crypto'
import { state } from '../state.js'
import { queueCalendarEventsWrite } from '../data.js'
import { requireAdminAuth } from '../auth.js'

const VALID_TYPES = ['general', 'recording', 'social', 'task']
const DATE_RE = /^\d{4}-\d{2}-\d{2}$/

function sanitize(ev) {
  return {
    id: ev.id,
    type: VALID_TYPES.includes(ev.type) ? ev.type : 'general',
    title: typeof ev.title === 'string' ? ev.title.slice(0, 300) : '',
    date: typeof ev.date === 'string' && DATE_RE.test(ev.date) ? ev.date : '',
    notes: typeof ev.notes === 'string' ? ev.notes.slice(0, 2000) : '',
    completed: Boolean(ev.completed),
    reminderDays: Number.isFinite(ev.reminderDays) && ev.reminderDays > 0 ? ev.reminderDays : 0,
    reminderSentAt: typeof ev.reminderSentAt === 'string' ? ev.reminderSentAt : undefined,
    createdAt: typeof ev.createdAt === 'string' ? ev.createdAt : new Date().toISOString(),
  }
}

export function register(app) {
  app.get('/api/admin-calendar-events', requireAdminAuth, (_req, res) => {
    res.json({ events: state.calendarEvents })
  })

  app.post('/api/admin-calendar-events', requireAdminAuth, (req, res) => {
    const { type, title, date, notes, reminderDays } = req.body ?? {}
    if (!title?.trim()) { res.status(400).json({ message: 'Title is required.' }); return }
    if (!date || !DATE_RE.test(date)) { res.status(400).json({ message: 'Valid date is required.' }); return }
    if (type && !VALID_TYPES.includes(type)) { res.status(400).json({ message: 'Invalid type.' }); return }

    const ev = sanitize({
      id: randomUUID(),
      type: type ?? 'general',
      title: String(title).trim(),
      date,
      notes: notes ?? '',
      completed: false,
      reminderDays: reminderDays ?? 0,
      createdAt: new Date().toISOString(),
    })

    state.calendarEvents.unshift(ev)
    queueCalendarEventsWrite()
    res.json({ ok: true, event: ev })
  })

  app.patch('/api/admin-calendar-events/:id', requireAdminAuth, (req, res) => {
    const { id } = req.params
    let found = false
    state.calendarEvents = state.calendarEvents.map(ev => {
      if (ev.id !== id) return ev
      found = true
      const patch = {}
      if (typeof req.body?.title === 'string') patch.title = req.body.title.trim().slice(0, 300)
      if (typeof req.body?.date === 'string' && DATE_RE.test(req.body.date)) patch.date = req.body.date
      if (typeof req.body?.notes === 'string') patch.notes = req.body.notes.trim().slice(0, 2000)
      if (typeof req.body?.completed === 'boolean') patch.completed = req.body.completed
      if (VALID_TYPES.includes(req.body?.type)) patch.type = req.body.type
      if (Number.isFinite(req.body?.reminderDays)) patch.reminderDays = req.body.reminderDays
      const dateChanged = patch.date && patch.date !== ev.date
      const reminderChanged = 'reminderDays' in patch && patch.reminderDays !== ev.reminderDays
      if (dateChanged || reminderChanged) patch.reminderSentAt = undefined
      return { ...ev, ...patch }
    })
    if (!found) { res.status(404).json({ message: 'Event not found.' }); return }
    queueCalendarEventsWrite()
    res.json({ ok: true })
  })

  app.delete('/api/admin-calendar-events/:id', requireAdminAuth, (req, res) => {
    const before = state.calendarEvents.length
    state.calendarEvents = state.calendarEvents.filter(ev => ev.id !== req.params.id)
    if (state.calendarEvents.length === before) { res.status(404).json({ message: 'Event not found.' }); return }
    queueCalendarEventsWrite()
    res.json({ ok: true })
  })
}