'use server'

import { auth } from '@/auth'
import { prisma } from '@/lib/prisma'
import { revalidatePath, revalidateTag } 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
  emailNotifications?: boolean
  desktopNotifications?: boolean
  anonymousAnalytics?: boolean
  theme?: 'light' | 'dark' | 'auto'
  fontSize?: 'small' | 'medium' | 'large'
}

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


    revalidatePath('/settings/ai', 'page')
    revalidatePath('/', 'layout')
    revalidateTag('ai-settings')

    return { success: true }
  } catch (error) {
    console.error('Error updating AI settings:', error)
    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,
          emailNotifications: false,
          desktopNotifications: false,
          anonymousAnalytics: false,
          theme: 'light' as const,
          fontSize: 'medium' 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,
        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,
        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,
      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
  }
}