import { ConvexHttpClient } from "convex/browser"
import { fetchQuery } from "convex/nextjs"
import { makeFunctionReference } from "convex/server"
import { api } from "@/convex/_generated/api"
import { hasConvexUrl } from "@/lib/convex-config"
import type { Product } from "@/lib/products/types"
import type { Manual } from "@/lib/manuals-types"

type ConvexProductDoc = {
  _id: string
  name: string
  description?: string
  price: number
  currency: string
  images: string[]
  metadata?: Record<string, string>
  stripeProductId?: string
  stripePriceId?: string
  active: boolean
}

type ConvexManualDoc = {
  filename: string
  path: string
  manufacturer: string
  category: string
  size?: number
  lastModified?: number
  searchTerms?: string[]
  commonNames?: string[]
  thumbnailUrl?: string
  manualUrl?: string
}

const LIST_MANUALS = makeFunctionReference<"query">("manuals:list")
const MANUALS_DASHBOARD = makeFunctionReference<"query">("manuals:dashboard")

let cachedServerConvexAdminClient: ConvexHttpClient | null | undefined
let cachedServerConvexPublicClient: ConvexHttpClient | null | undefined

function getServerConvexClient(useAdminAuth: boolean) {
  const cacheKey = useAdminAuth ? "admin" : "public"
  const cachedClient = useAdminAuth
    ? cachedServerConvexAdminClient
    : cachedServerConvexPublicClient
  if (cachedClient !== undefined) {
    return cachedClient
  }

  const convexUrl = process.env.CONVEX_URL || process.env.NEXT_PUBLIC_CONVEX_URL
  if (!convexUrl) {
    if (useAdminAuth) {
      cachedServerConvexAdminClient = null
      return cachedServerConvexAdminClient
    }

    cachedServerConvexPublicClient = null
    return cachedServerConvexPublicClient
  }

  const client = new ConvexHttpClient(convexUrl)
  const adminKey = process.env.CONVEX_SELF_HOSTED_ADMIN_KEY
  if (useAdminAuth && adminKey) {
    ;(
      client as ConvexHttpClient & {
        setAdminAuth?: (token: string) => void
      }
    ).setAdminAuth?.(adminKey)
  }

  if (cacheKey === "admin") {
    cachedServerConvexAdminClient = client
    return cachedServerConvexAdminClient
  }

  cachedServerConvexPublicClient = client
  return cachedServerConvexPublicClient
}

async function queryManualsWithAuthFallback<TData>(
  label: string,
  queryRef: ReturnType<typeof makeFunctionReference<"query">>,
  fallback: TData
): Promise<TData> {
  const adminKey = process.env.CONVEX_SELF_HOSTED_ADMIN_KEY
  const adminClient = getServerConvexClient(true)

  if (adminClient) {
    try {
      return (await adminClient.query(queryRef, {})) as TData
    } catch (error) {
      console.error(`[convex-service] ${label} admin query failed`, error)
      if (!adminKey) {
        return fallback
      }
    }
  }

  const publicClient = getServerConvexClient(false)
  if (!publicClient) {
    return fallback
  }

  return await safeFetchQuery(
    `${label}.public`,
    publicClient.query(queryRef, {}),
    fallback
  )
}

type ConvexOrderItem = {
  productId?: string | null
  productName: string
  price: number
  quantity: number
  priceId: string
  image?: string
}

export type ConvexAdminOrder = {
  id: string
  customerEmail: string
  customerName?: string
  totalAmount: number
  currency: string
  status: "pending" | "paid" | "fulfilled" | "cancelled" | "refunded"
  stripeSessionId: string | null
  paymentIntentId: string | null
  createdAt: string
  updatedAt: string
  shippingAddress?: {
    name?: string
    address?: string
    city?: string
    state?: string
    zipCode?: string
    country?: string
  }
  items: ConvexOrderItem[]
}

async function safeFetchQuery<TData>(
  label: string,
  query: Promise<TData>,
  fallback: TData
): Promise<TData> {
  try {
    return await query
  } catch (error) {
    console.error(`[convex-service] ${label} failed`, error)
    return fallback
  }
}

function mapConvexProduct(product: ConvexProductDoc): Product {
  return {
    id: product._id,
    stripeId: product.stripeProductId ?? product._id,
    name: product.name,
    description: product.description ?? null,
    price: product.price,
    currency: product.currency,
    images: product.images ?? [],
    metadata: product.metadata,
    priceId: product.stripePriceId,
  }
}

function mapConvexManual(manual: ConvexManualDoc): Manual {
  return {
    filename: manual.filename,
    path: manual.path,
    manufacturer: manual.manufacturer,
    category: manual.category,
    size: manual.size,
    lastModified: manual.lastModified
      ? new Date(manual.lastModified)
      : undefined,
    searchTerms: manual.searchTerms,
    commonNames: manual.commonNames,
    thumbnailUrl: manual.thumbnailUrl,
  }
}

export async function listConvexProducts(): Promise<Product[]> {
  if (!hasConvexUrl()) {
    return []
  }

  const products = await safeFetchQuery(
    "products.listActive",
    fetchQuery(api.products.listActive, {}),
    [] as ConvexProductDoc[]
  )
  return (products as ConvexProductDoc[]).map(mapConvexProduct)
}

export async function listConvexAdminProducts(
  search?: string
): Promise<Product[]> {
  if (!hasConvexUrl()) {
    return []
  }

  const products = await safeFetchQuery(
    "products.listAdmin",
    fetchQuery(api.products.listAdmin, { search }),
    [] as ConvexProductDoc[]
  )
  return (products as ConvexProductDoc[]).map(mapConvexProduct)
}

export async function getConvexProduct(id: string): Promise<Product | null> {
  if (!hasConvexUrl()) {
    return null
  }

  const products = await safeFetchQuery(
    "products.listAdmin",
    fetchQuery(api.products.listAdmin, {}),
    [] as ConvexProductDoc[]
  )
  const match = (products as ConvexProductDoc[]).find((product) => {
    return product._id === id || product.stripeProductId === id
  })

  return match ? mapConvexProduct(match) : null
}

export async function listConvexManuals(): Promise<Manual[]> {
  if (!hasConvexUrl()) {
    return []
  }

  const manuals = await queryManualsWithAuthFallback(
    "manuals.list",
    LIST_MANUALS,
    [] as ConvexManualDoc[]
  )
  return (manuals as ConvexManualDoc[]).map(mapConvexManual)
}

export async function getConvexManualDashboard() {
  if (!hasConvexUrl()) {
    return null
  }

  return await queryManualsWithAuthFallback(
    "manuals.dashboard",
    MANUALS_DASHBOARD,
    null
  )
}

export async function getConvexOrderMetrics() {
  if (!hasConvexUrl()) {
    return null
  }

  return await safeFetchQuery(
    "orders.getMetrics",
    fetchQuery(api.orders.getMetrics, {}),
    null
  )
}

export async function listConvexOrders(options?: {
  status?: ConvexAdminOrder["status"]
  search?: string
}): Promise<ConvexAdminOrder[]> {
  if (!hasConvexUrl()) {
    return []
  }

  return await safeFetchQuery(
    "orders.listAdmin",
    fetchQuery(api.orders.listAdmin, {
      status: options?.status,
      search: options?.search,
    }),
    [] as ConvexAdminOrder[]
  )
}