import { createRequire } from 'node:module'
import type { DeviceSnapshot } from '../domain/device/device.js'
import type { Device } from '../domain/device/device.js'
import { DeviceParameter } from '../domain/device/device_parameter.js'

const require = createRequire(import.meta.url)
const tr181Catalog: Array<{ path: string; writable: boolean; deviceClass: string }> =
  require('../../config/tr181-catalog.json')

// Index chargé une fois au démarrage — O(1) lookup
const catalogIndex = new Map(tr181Catalog.map((e) => [e.path, e.writable]))
const catalogWritableIndex = new Set(
  tr181Catalog.filter((e) => e.writable).map((e) => e.path)
)

/** Remplace les segments numériques par {i} pour matcher les entrées du catalogue */
export function normalizePath(path: string): string {
  return path.replace(/\.\d+\./g, '.{i}.').replace(/\.\d+$/, '.{i}')
}

export type WritabilitySource = 'live' | 'catalog' | 'default' | 'unknown'

export interface WritabilityResult {
  writable: boolean | null
  source: WritabilitySource
}

/**
 * Résout la writabilité d'un paramètre à partir de l'état persisté du device.
 *
 * Logique :
 *  1. gpnStatus = 'supported' → parameters[] = writable, properties[] = RO (source fiable)
 *  2. gpnStatus = 'unsupported' → catalogue TR-181 → absent = writable=true (défaut R/W)
 *  3. gpnStatus = 'unknown' → catalogue TR-181 → absent = writable=null (genuinement inconnu)
 */
export function resolveWritability(snapshot: DeviceSnapshot, paramPath: string): WritabilityResult {
  const { gpnStatus, parameters, properties } = snapshot

  if (gpnStatus === 'supported') {
    if (parameters.some((p) => p.name === paramPath)) return { writable: true, source: 'live' }
    if (properties.some((p) => p.name === paramPath)) return { writable: false, source: 'live' }
  }

  // gpnStatus = 'unsupported' ou 'unknown' → consulter le catalogue
  const normalized = normalizePath(paramPath)
  if (catalogIndex.has(normalized)) {
    return { writable: catalogIndex.get(normalized)!, source: 'catalog' }
  }

  // Absent du catalogue
  if (gpnStatus === 'unsupported') return { writable: true, source: 'default' }
  return { writable: null, source: 'unknown' }
}

/**
 * Reclassify device properties as parameters using the TR-181 catalog.
 * Properties that are writable per the catalog are moved to parameters.
 * Should be called after updateFromValues when gpnStatus is 'unsupported'.
 */
export function reclassifyDeviceFromCatalog(device: Device): number {
  const properties = device.getProperties()
  let reclassified = 0

  for (const prop of properties) {
    const normalized = normalizePath(prop.name)
    if (catalogWritableIndex.has(normalized)) {
      const snap = prop.toSnapshot()
      device.setParameter(
        new DeviceParameter(snap.name, snap.value, snap.type, snap.createdAt, snap.updatedAt, snap.notification, snap.accessList)
      )
      ;(device as any)._properties.delete(prop.name)
      reclassified++
    }
  }

  return reclassified
}