'use server'

import prisma from '@/lib/prisma'
import { auth } from '@/auth'
import { sendEmail } from '@/lib/mail'

async function checkAdmin() {
  const session = await auth()
  if (!session?.user?.id || (session.user as any).role !== 'ADMIN') {
    throw new Error('Unauthorized: Admin access required')
  }
  return session
}

export async function testEmail(provider: 'resend' | 'smtp' = 'smtp') {
  const session = await checkAdmin()
  const email = session.user?.email

  if (!email) throw new Error("No admin email found")

  const subject = provider === 'resend'
    ? "Memento Resend Test"
    : "Memento SMTP Test"

  const html = provider === 'resend'
    ? "<p>This is a test email from your Memento instance. <strong>Resend is working!</strong></p>"
    : "<p>This is a test email from your Memento instance. <strong>SMTP is working!</strong></p>"

  const result = await sendEmail({
    to: email,
    subject,
    html,
  }, provider)

  return result
}

export async function getSystemConfig() {
  await checkAdmin()
  // Reuse the cached version from lib/config
  const { getSystemConfig: getCachedConfig } = await import('@/lib/config')
  return getCachedConfig()
}

/** Keys that may be cleared (empty string) to fall back to chat / defaults. */
const CLEARABLE_CONFIG_KEYS = new Set([
  'AI_PROVIDER_SLIDES',
  'AI_MODEL_SLIDES',
])

export async function updateSystemConfig(data: Record<string, string>) {
  await checkAdmin()

  try {
    // Filter out empty values but keep 'false' as valid.
    // Slides provider/model may be empty intentionally (= use Chat fallback).
    const toUpsert: Record<string, string> = {}
    const toDelete: string[] = []

    for (const [key, value] of Object.entries(data)) {
      if (value === null || value === undefined) continue
      if (value === '' && CLEARABLE_CONFIG_KEYS.has(key)) {
        toDelete.push(key)
        continue
      }
      if (value === '') continue
      toUpsert[key] = value
    }

    const operations = [
      ...Object.entries(toUpsert).map(([key, value]) =>
        prisma.systemConfig.upsert({
          where: { key },
          update: { value },
          create: { key, value },
        }),
      ),
      ...toDelete.map((key) =>
        prisma.systemConfig.deleteMany({ where: { key } }),
      ),
    ]

    if (operations.length > 0) {
      await prisma.$transaction(operations)
    }

    return { success: true }
  } catch (error) {
    console.error('Failed to update settings:', error)
    return { error: 'Failed to update settings' }
  }
}