import bcrypt from 'bcryptjs'
import jwt from 'jsonwebtoken'
import crypto from 'crypto'
import { authenticator } from 'otplib'
import qrcode from 'qrcode'
import { getMarketplaceHomepageContent, saveMarketplaceHomepageContent } from '../../services/platformContentService'
import { generateInvoicePdf, buildInvoiceNumber } from '../../services/invoicePdfService'
import { sendTransactionalEmail } from '../../services/notificationService'
import * as presenter from './admin.presenter'
import * as repo from './admin.repo'

const ADMIN_RESET_TTL_MINUTES = 60

const PLAN_MONTHLY_AMOUNT: Record<string, number> = {
  STARTER: 2990,
  GROWTH:  3990,
  PRO:     99900,
}

function signAdminToken(adminId: string) {
  return jwt.sign({ sub: adminId, type: 'admin' }, process.env.JWT_SECRET!, { expiresIn: '8h' })
}

function toAuditJson<T>(value: T) {
  return JSON.parse(JSON.stringify(value))
}

function ensureAdminBasePath(baseUrl: string) {
  try {
    const url = new URL(baseUrl)
    const pathname = url.pathname.replace(/\/$/, '')
    if (!pathname.endsWith('/admin')) url.pathname = `${pathname}/admin`
    return url.toString().replace(/\/$/, '')
  } catch {
    const trimmed = baseUrl.replace(/\/$/, '')
    return trimmed.endsWith('/admin') ? trimmed : `${trimmed}/admin`
  }
}

export async function login(email: string, password: string, totpCode?: string) {
  const admin = await repo.findAdminByEmail(email)
  if (!admin || !admin.isActive) return null

  const valid = await bcrypt.compare(password, admin.passwordHash)
  if (!valid) return null

  if (admin.totpEnabled) {
    if (!totpCode) return { totpRequired: true } as const
    if (!authenticator.verify({ token: totpCode, secret: admin.totpSecret! })) {
      return { invalidTotp: true } as const
    }
  }

  await repo.updateAdminLastLogin(admin.id)
  await repo.createAuditLog({
    adminUserId: admin.id,
    action: 'ADMIN_LOGIN',
    resource: 'AdminUser',
    resourceId: admin.id,
  })

  return presenter.presentAdminSession(admin, signAdminToken(admin.id))
}

export async function setupTotp(adminId: string, email: string) {
  const secret = authenticator.generateSecret()
  await repo.updateAdminTotpSecret(adminId, secret)
  const otpauth = authenticator.keyuri(email, 'RentalDriveGo Admin', secret)
  const qrCode = await qrcode.toDataURL(otpauth)
  return { secret, qrCode }
}

export async function verifyTotp(adminId: string, code: string) {
  const admin = await repo.findAdminByIdOrThrow(adminId)
  if (!admin.totpSecret) return false

  const valid = authenticator.verify({ token: code, secret: admin.totpSecret })
  if (valid) await repo.enableAdminTotp(adminId)
  return valid
}

export async function forgotPassword(email: string) {
  const admin = await repo.findAdminByEmail(email)
  if (!admin || !admin.isActive) return

  const rawToken = crypto.randomBytes(32).toString('hex')
  const expiresAt = new Date(Date.now() + ADMIN_RESET_TTL_MINUTES * 60 * 1000)
  await repo.setAdminPasswordReset(admin.id, rawToken, expiresAt)

  const adminUrl = ensureAdminBasePath(
    process.env.ADMIN_URL ?? process.env.NEXT_PUBLIC_ADMIN_URL ?? 'http://localhost:3000/admin',
  )
  const resetUrl = `${adminUrl}/reset-password?token=${rawToken}`

  await sendTransactionalEmail({
    to: admin.email,
    subject: 'Reset your RentalDriveGo admin password',
    html: `<p>Hi ${admin.firstName},</p><p><a href="${resetUrl}">Reset password</a></p><p>Expires in ${ADMIN_RESET_TTL_MINUTES} minutes.</p>`,
    text: `Hi ${admin.firstName},\n\nReset here: ${resetUrl}\n\nExpires in ${ADMIN_RESET_TTL_MINUTES} minutes.`,
  }).catch((err) => console.error('[AdminForgotPassword]', err?.message))
}

export async function resetPassword(token: string, password: string) {
  const admin = await repo.findAdminByResetToken(token)
  if (!admin) return false

  await repo.updateAdminPassword(admin.id, await bcrypt.hash(password, 12))
  return true
}

export async function listCompanies(query: { q?: string; status?: string; plan?: string; page: number; pageSize: number }) {
  const { data, total } = await repo.listCompaniesPage(query)
  return presenter.presentPaginated(data, total, query.page, query.pageSize)
}

export function getCompany(id: string) {
  return repo.getCompanyDetail(id)
}

export async function updateCompany(id: string, body: any, adminId: string, ip?: string) {
  const before = await repo.getCompanyUpdateSnapshot(id)
  const updated = await repo.applyCompanyUpdate(id, body, before)
  await repo.createAuditLog({
    adminUserId: adminId,
    action: 'UPDATE_COMPANY',
    resource: 'Company',
    resourceId: id,
    companyId: id,
    before: toAuditJson(before),
    after: toAuditJson(body),
    ipAddress: ip,
  })
  return updated
}

export async function setCompanyStatus(id: string, status: string, reason: string | undefined, adminId: string, ip?: string) {
  const before = await repo.getCompanyUpdateSnapshot(id)
  const updated = await repo.updateCompanyStatus(id, status)
  await repo.createAuditLog({
    adminUserId: adminId,
    action: `SET_COMPANY_STATUS_${status}`,
    resource: 'Company',
    resourceId: id,
    companyId: id,
    before: { status: before.status },
    after: { status },
    note: reason,
    ipAddress: ip,
  })
  return updated
}

export async function deleteCompany(id: string, adminId: string, ip?: string) {
  await repo.deleteCompany(id)
  await repo.createAuditLog({
    adminUserId: adminId,
    action: 'DELETE_COMPANY',
    resource: 'Company',
    resourceId: id,
    ipAddress: ip,
  })
}

export async function impersonateCompany(id: string, adminId: string, ip?: string) {
  const company = await repo.getCompanyForImpersonation(id)
  const token = jwt.sign(
    {
      sub: company.employees[0]?.id,
      companyId: company.id,
      isImpersonation: true,
      type: 'employee',
    },
    process.env.JWT_SECRET!,
    { expiresIn: '30m' },
  )

  await repo.createAuditLog({
    adminUserId: adminId,
    action: 'IMPERSONATE_COMPANY',
    resource: 'Company',
    resourceId: id,
    companyId: id,
    ipAddress: ip,
  })

  return { token, expiresIn: 1800 }
}

export async function listRenters(query: { q?: string; blocked?: string; page: number; pageSize: number }) {
  const { data, total } = await repo.listRentersPage(query)
  return presenter.presentPaginated(data, total, query.page, query.pageSize)
}

export function setRenterActive(id: string, isActive: boolean) {
  return repo.updateRenterActive(id, isActive)
}

export function getPlatformMetrics() {
  return repo.getPlatformMetricCounts()
}

export async function getAuditLogs(query: { adminId?: string; action?: string; companyId?: string; entityId?: string; page: number; pageSize: number }) {
  const { data, total } = await repo.listAuditLogsPage(query)
  return presenter.presentPaginated(data, total, query.page, query.pageSize)
}

export async function listAdmins() {
  const admins = await repo.listAdmins()
  return admins.map((admin) => presenter.presentAdminUser(admin))
}

export async function createAdmin(body: { email: string; firstName: string; lastName: string; role: string; password: string; permissions?: any[] }) {
  const admin = await repo.createAdmin({
    ...body,
    passwordHash: await bcrypt.hash(body.password, 12),
  })
  return presenter.presentAdminUser(admin)
}

export function updateAdminRole(id: string, role: string) {
  return repo.updateAdminRole(id, role)
}

export async function updateAdminPermissions(id: string, permissions: any[]) {
  const admin = await repo.replaceAdminPermissions(id, permissions)
  return presenter.presentAdminUser(admin)
}

export async function getBilling(query: { status?: string; plan?: string; page: number; pageSize: number }) {
  const [{ data, total }, activeSubscriptions, stats] = await Promise.all([
    repo.listBillingPage(query),
    repo.listActiveSubscriptionsForMrr(),
    repo.getBillingStatusCounts(),
  ])

  const mrr = activeSubscriptions.reduce((acc, subscription) => {
    const monthlyAmount = PLAN_MONTHLY_AMOUNT[subscription.plan] ?? 0
    return acc + (subscription.billingPeriod === 'ANNUAL' ? Math.round(monthlyAmount * 10 / 12) : monthlyAmount)
  }, 0)

  return presenter.presentPaginated(data, total, query.page, query.pageSize, {
    stats: { mrr, ...stats },
  })
}

export async function getCompanyInvoices(companyId: string, query: { page: number; pageSize: number }) {
  const { data, total } = await repo.listCompanyInvoicesPage(companyId, query)
  return presenter.presentPaginated(data, total, query.page, query.pageSize)
}

export async function getInvoicePdf(invoiceId: string) {
  const invoice = await repo.getInvoicePdfRecord(invoiceId)
  const invoiceNumber = buildInvoiceNumber(invoice.id, invoice.createdAt)
  const transactionId = invoice.amanpayTransactionId ?? invoice.paypalCaptureId ?? null
  const pdfBuffer = await generateInvoicePdf({
    invoiceNumber,
    issueDate: invoice.createdAt.toISOString(),
    dueDate: invoice.status === 'PENDING' ? invoice.createdAt.toISOString() : null,
    company: {
      name: invoice.company.name,
      email: invoice.company.email,
      phone: invoice.company.phone,
      address: invoice.company.address,
    },
    subscription: {
      plan: invoice.subscription.plan,
      billingPeriod: invoice.subscription.billingPeriod,
      currentPeriodStart: invoice.subscription.currentPeriodStart?.toISOString(),
      currentPeriodEnd: invoice.subscription.currentPeriodEnd?.toISOString(),
      currency: invoice.subscription.currency,
    },
    amount: invoice.amount,
    currency: invoice.currency,
    status: invoice.status,
    paymentProvider: invoice.paymentProvider,
    transactionId,
    paidAt: invoice.paidAt?.toISOString(),
  })

  return { pdfBuffer, invoiceNumber }
}

export function getMarketplaceHomepage() {
  return getMarketplaceHomepageContent()
}

export async function updateMarketplaceHomepage(homepage: any, adminId: string, ip?: string) {
  const saved = await saveMarketplaceHomepageContent(homepage)
  await repo.createAuditLog({
    adminUserId: adminId,
    action: 'UPDATE',
    resource: 'MarketplaceHomepage',
    after: toAuditJson(saved),
    ipAddress: ip,
    userAgent: undefined,
  })
  return saved
}