import CheckinTask from '#models/checkin_task'
import Invoice from '#models/invoice'
import { hashCheckinToken } from '#services/checkin_token'
import { recordActivity } from '#services/activity_recorder'
import { cancelFutureRelances, scheduleRelancesForInvoice } from '#services/relance_scheduler'
import db from '@adonisjs/lucid/services/db'
import env from '#start/env'
import { DateTime } from 'luxon'
import type { HttpContext } from '@adonisjs/core/http'

const CHECKIN_TTL_HOURS = 24

/**
 * Construit l'URL de redirect SPA selon le résultat. Le SPA lit ces
 * query params pour afficher un toast et router l'utilisateur.
 */
function spaRedirectUrl(
  result: 'paid' | 'pending' | 'expired' | 'invalid' | 'already_answered',
  invoice?: Pick<Invoice, 'id' | 'numero'>
): string {
  const base = env.get('WEB_URL', 'http://localhost:5173')
  const params = new URLSearchParams({ checkin: result })
  if (invoice) params.set('invoice', invoice.numero)
  const path = invoice ? `/factures/${invoice.id}` : '/'
  return `${base}${path}?${params.toString()}`
}

type ResolvedTask = { task: CheckinTask; invoice: Invoice } | { redirect: string }

/**
 * Lookup + validation commune aux deux endpoints (paid / pending).
 * Retourne soit la task validée soit une URL de redirect d'erreur.
 */
async function resolveCheckin(token: string): Promise<ResolvedTask> {
  const hashed = hashCheckinToken(token)
  const task = await CheckinTask.query().where('token_hash', hashed).first()
  if (!task) {
    return { redirect: spaRedirectUrl('invalid') }
  }

  if (task.status === 'answered') {
    const inv = await Invoice.find(task.invoiceId)
    return { redirect: spaRedirectUrl('already_answered', inv ?? undefined) }
  }

  // Expiration : 24h après l'envoi (sentAt). Tant qu'elle n'a pas été
  // envoyée, le link n'est pas censé exister côté user — sécurité belt.
  if (task.sentAt && task.sentAt.plus({ hours: CHECKIN_TTL_HOURS }) < DateTime.now()) {
    task.status = 'expired'
    await task.save()
    return { redirect: spaRedirectUrl('expired') }
  }

  const invoice = await Invoice.query().where('id', task.invoiceId).preload('client').first()
  if (!invoice) {
    return { redirect: spaRedirectUrl('invalid') }
  }

  return { task, invoice }
}

export default class CheckinController {
  /**
   * GET /api/v1/checkin/:token/paid
   *
   * L'utilisateur clique "j'ai été payé". On marque la facture payée +
   * cancel les relances futures + bonus rubis (idempotent avec mark-paid).
   * Redirect SPA avec `?checkin=paid&invoice=<numero>`.
   *
   * Public : pas d'auth Bearer, c'est un lien dans un email.
   */
  async respondPaid({ params, response }: HttpContext) {
    const result = await resolveCheckin(params.token)
    if ('redirect' in result) {
      return response.redirect(result.redirect)
    }
    const { task, invoice } = result

    await db.transaction(async (trx) => {
      task.useTransaction(trx)
      task.status = 'answered'
      task.answer = 'paid'
      task.answeredAt = DateTime.now()
      await task.save()

      // Mark paid (mêmes effets que POST /invoices/:id/mark-paid).
      if (invoice.status !== 'paid') {
        invoice.useTransaction(trx)
        invoice.status = 'paid'
        invoice.paidAt = DateTime.now()
        invoice.rubisEarned = invoice.rubisEarned + 1
        await invoice.save()

        await trx
          .from('organizations')
          .where('id', invoice.organizationId)
          .increment('rubis_count', 1)

        await recordActivity({
          organizationId: invoice.organizationId,
          kind: 'invoice_paid',
          label: `Facture <b>${invoice.numero}</b> marquée encaissée via check-in`,
          meta: { invoiceId: invoice.id, clientId: invoice.clientId },
          trx,
        })

        await cancelFutureRelances(invoice.id, trx)
      }
    })

    return response.redirect(spaRedirectUrl('paid', invoice))
  }

  /**
   * GET /api/v1/checkin/:token/pending
   *
   * L'utilisateur clique "toujours en attente". On marque la task
   * answered, puis on programme les relances client.
   */
  async respondPending({ params, response }: HttpContext) {
    const result = await resolveCheckin(params.token)
    if ('redirect' in result) {
      return response.redirect(result.redirect)
    }
    const { task, invoice } = result

    await db.transaction(async (trx) => {
      if (invoice.planId) {
        invoice.useTransaction(trx)
        await scheduleRelancesForInvoice(invoice, trx)
      }

      task.useTransaction(trx)
      task.status = 'answered'
      task.answer = 'still_pending'
      task.answeredAt = DateTime.now()
      await task.save()
    })

    return response.redirect(spaRedirectUrl('pending', invoice))
  }
}