'use server'

import { auth } from '@/auth'
import { prisma } from '@/lib/prisma'
import { revalidatePath, updateTag } from 'next/cache'

export type UserAISettingsData = {
  titleSuggestions?: boolean
  semanticSearch?: boolean
  paragraphRefactor?: boolean
  memoryEcho?: boolean
  memoryEchoFrequency?: 'daily' | 'weekly' | 'custom'
  aiProvider?: 'auto' | 'openai' | 'ollama'
  preferredLanguage?: 'auto' | 'en' | 'fr' | 'es' | 'de' | 'fa' | 'it' | 'pt' | 'ru' | 'zh' | 'ja' | 'ko' | 'ar' | 'hi' | 'nl' | 'pl'
  demoMode?: boolean
  showRecentNotes?: boolean
  notesViewMode?: 'masonry' | 'tabs' | 'list'
  emailNotifications?: boolean
  desktopNotifications?: boolean
  anonymousAnalytics?: boolean
  fontSize?: 'small' | 'medium' | 'large'
}

/** Only fields that exist on `UserAISettings` in Prisma (excludes e.g. `theme`, which lives on `User`). */
const USER_AI_SETTINGS_PRISMA_KEYS = [
  'titleSuggestions',
  'semanticSearch',
  'paragraphRefactor',
  'memoryEcho',
  'memoryEchoFrequency',
  'aiProvider',
  'preferredLanguage',
  'fontSize',
  'demoMode',
  'showRecentNotes',
  'notesViewMode',
  'emailNotifications',
  'desktopNotifications',
  'anonymousAnalytics',
] as const

type UserAISettingsPrismaKey = (typeof USER_AI_SETTINGS_PRISMA_KEYS)[number]

function pickUserAISettingsForDb(input: UserAISettingsData): Partial<Record<UserAISettingsPrismaKey, unknown>> {
  const out: Partial<Record<UserAISettingsPrismaKey, unknown>> = {}
  for (const key of USER_AI_SETTINGS_PRISMA_KEYS) {
    const v = input[key]
    if (v !== undefined) {
      out[key] = v
    }
  }
  if (out.notesViewMode === 'list') {
    out.notesViewMode = 'tabs'
  }
  if (
    out.notesViewMode != null &&
    out.notesViewMode !== 'masonry' &&
    out.notesViewMode !== 'tabs'
  ) {
    delete out.notesViewMode
  }
  return out
}

/**
 * Update AI settings for the current user
 */
export async function updateAISettings(settings: UserAISettingsData) {

  const session = await auth()


  if (!session?.user?.id) {
    console.error('[updateAISettings] Unauthorized: No session or user ID')
    throw new Error('Unauthorized')
  }

  try {
    const data = pickUserAISettingsForDb(settings)
    if (Object.keys(data).length === 0) {
      return { success: true }
    }

    // Valeurs scalaires uniquement (pickUserAISettingsForDb) — cast pour éviter UpdateOperations vs create.
    const payload = data as Record<string, string | boolean | undefined>

    // Upsert settings (create if not exists, update if exists)
    await prisma.userAISettings.upsert({
      where: { userId: session.user.id },
      create: {
        userId: session.user.id,
        ...payload,
      },
      update: payload,
    })

    revalidatePath('/settings/ai', 'page')
    revalidatePath('/settings/appearance', 'page')
    revalidatePath('/', 'layout')
    updateTag('ai-settings')

    return { success: true }
  } catch (error) {
    console.error('Error updating AI settings:', error)
    const raw = error instanceof Error ? error.message : String(error)
    const isSchema =
      /no such column|notesViewMode|Unknown column|does not exist/i.test(raw) ||
      (typeof raw === 'string' && raw.includes('UserAISettings') && raw.includes('column'))
    if (isSchema) {
      throw new Error(
        'Schéma base de données obsolète : colonne notesViewMode manquante. Dans le dossier keep-notes, exécutez : npx prisma db push (ou appliquez les migrations Prisma).'
      )
    }
    throw new Error('Failed to update AI settings')
  }
}

/**
 * Get AI settings for the current user (Cached)
 */
import { unstable_cache } from 'next/cache'

// Internal cached function to fetch settings from DB
const getCachedAISettings = unstable_cache(
  async (userId: string) => {
    try {
      const settings = await prisma.userAISettings.findUnique({
        where: { userId }
      })

      if (!settings) {
        return {
          titleSuggestions: true,
          semanticSearch: true,
          paragraphRefactor: true,
          memoryEcho: true,
          memoryEchoFrequency: 'daily' as const,
          aiProvider: 'auto' as const,
          preferredLanguage: 'auto' as const,
          demoMode: false,
          showRecentNotes: false,
          notesViewMode: 'masonry' as const,
          emailNotifications: false,
          desktopNotifications: false,
          anonymousAnalytics: false,
          theme: 'light' as const,
          fontSize: 'medium' as const
        }
      }

      const raw = settings.notesViewMode
      const viewMode =
        raw === 'masonry'
          ? ('masonry' as const)
          : raw === 'list' || raw === 'tabs'
            ? ('tabs' as const)
            : ('masonry' as const)

      return {
        titleSuggestions: settings.titleSuggestions,
        semanticSearch: settings.semanticSearch,
        paragraphRefactor: settings.paragraphRefactor,
        memoryEcho: settings.memoryEcho,
        memoryEchoFrequency: (settings.memoryEchoFrequency || 'daily') as 'daily' | 'weekly' | 'custom',
        aiProvider: (settings.aiProvider || 'auto') as 'auto' | 'openai' | 'ollama',
        preferredLanguage: (settings.preferredLanguage || 'auto') as 'auto' | 'en' | 'fr' | 'es' | 'de' | 'fa' | 'it' | 'pt' | 'ru' | 'zh' | 'ja' | 'ko' | 'ar' | 'hi' | 'nl' | 'pl',
        demoMode: settings.demoMode,
        showRecentNotes: settings.showRecentNotes,
        notesViewMode: viewMode,
        emailNotifications: settings.emailNotifications,
        desktopNotifications: settings.desktopNotifications,
        anonymousAnalytics: settings.anonymousAnalytics,
        // theme: 'light' as const, // REMOVED: Should not be handled here or hardcoded
        fontSize: (settings.fontSize || 'medium') as 'small' | 'medium' | 'large'
      }
    } catch (error) {
      console.error('Error getting AI settings:', error)
      // Return defaults on error
      return {
        titleSuggestions: true,
        semanticSearch: true,
        paragraphRefactor: true,
        memoryEcho: true,
        memoryEchoFrequency: 'daily' as const,
        aiProvider: 'auto' as const,
        preferredLanguage: 'auto' as const,
        demoMode: false,
        showRecentNotes: false,
        notesViewMode: 'masonry' as const,
        emailNotifications: false,
        desktopNotifications: false,
        anonymousAnalytics: false,
        theme: 'light' as const,
        fontSize: 'medium' as const
      }
    }
  },
  ['user-ai-settings'],
  { tags: ['ai-settings'] }
)

export async function getAISettings(userId?: string) {
  let id = userId

  if (!id) {
    const session = await auth()
    id = session?.user?.id
  }

  // Return defaults for non-logged-in users
  if (!id) {
    return {
      titleSuggestions: true,
      semanticSearch: true,
      paragraphRefactor: true,
      memoryEcho: true,
      memoryEchoFrequency: 'daily' as const,
      aiProvider: 'auto' as const,
      preferredLanguage: 'auto' as const,
      demoMode: false,
      showRecentNotes: false,
      notesViewMode: 'masonry' as const,
      emailNotifications: false,
      desktopNotifications: false,
      anonymousAnalytics: false,
      theme: 'light' as const,
      fontSize: 'medium' as const
    }
  }

  return getCachedAISettings(id)
}

/**
 * Get user's preferred AI provider
 */
export async function getUserAIPreference(): Promise<'auto' | 'openai' | 'ollama'> {
  const settings = await getAISettings()
  return settings.aiProvider
}

/**
 * Check if a specific AI feature is enabled for the user
 */
export async function isAIFeatureEnabled(feature: keyof UserAISettingsData): Promise<boolean> {
  const settings = await getAISettings()

  switch (feature) {
    case 'titleSuggestions':
      return settings.titleSuggestions
    case 'semanticSearch':
      return settings.semanticSearch
    case 'paragraphRefactor':
      return settings.paragraphRefactor
    case 'memoryEcho':
      return settings.memoryEcho
    default:
      return true
  }
}