import { useState, useEffect, useMemo } from 'react'
import { Linking, Alert } from 'react-native'

import { subscription, useSession } from '@/lib/auth'
import type { StripePricingTableResponse, SubscriptionListItem } from '@/lib/auth'

interface CreditPlan {
  amountInCents: number
  credits: number
  popular?: boolean
  name: string
  currency: string
  featureList: string[]
}



export function useMembership() {
  const { data: session } = useSession()
  const [selectedPlanIndex, setSelectedPlanIndex] = useState(0)
  const [stripePricingData, setStripePricingData] = useState<StripePricingTableResponse>(null)
  const [authSubscriptions, setAuthSubscriptions] = useState<any>(null)
  const [isStripePricingLoading, setIsStripePricingLoading] = useState(false)
  const [isLoadingSubscriptions, setIsLoadingSubscriptions] = useState(false)

  const fetchStripePricing = async () => {
    setIsStripePricingLoading(true)
    const { data, error } = await subscription.plans({
      query: {
        id: process.env.EXPO_PUBLIC_STRIPE_PRICING_TABLE_ID || '',
        key: process.env.EXPO_PUBLIC_STRIPE_PRICING_TABLE_KEY || '',
      },
    })
    setIsStripePricingLoading(false)
    if (!error) setStripePricingData(data)
  }

  const fetchAuthSubscriptions = async () => {
    if (!session?.user?.id) return
    setIsLoadingSubscriptions(true)
    const { data, error } = await subscription.list({
      query: { referenceId: session.user.id },
    })
    setIsLoadingSubscriptions(false)
    if (!error) setAuthSubscriptions(data)
  }

  useEffect(() => {
    fetchStripePricing()
  }, [])

  useEffect(() => {
    if (session?.user?.id) fetchAuthSubscriptions()
  }, [session?.user?.id])

  const licensedSubscriptions = authSubscriptions?.filter((sub: SubscriptionListItem) => sub.type === 'licenced') || []
  const meteredSubscriptions = authSubscriptions?.filter((sub: SubscriptionListItem) => sub.type === 'metered') || []

  const activeAuthSubscription = licensedSubscriptions.find(
    (sub: any) => sub.status === 'active' || sub.status === 'trialing'
  )

  const hasActiveSubscription = !!(
    activeAuthSubscription &&
    activeAuthSubscription.cancelAtPeriodEnd === false &&
    activeAuthSubscription.status === 'active'
  )

  const creditBalance = meteredSubscriptions?.[0]?.creditBalance?.remainingTokenBalance || 0

  const creditPlans = useMemo((): CreditPlan[] => {
    if (!stripePricingData?.pricing_table_items) return []
    return stripePricingData.pricing_table_items
      .filter((item) => item.recurring?.interval === 'month')
      .map((item) => ({
        amountInCents: parseInt(item.amount),
        credits: parseInt(item.amount),
        popular: item.is_highlight || item.highlight_text === 'most_popular',
        name: item.name || '',
        currency: item.currency || 'usd',
        featureList: item.feature_list || [],
      }))
  }, [stripePricingData?.pricing_table_items])

  const selectedPlan = creditPlans[selectedPlanIndex] || creditPlans[0]

  const createSubscription = async ({ priceId, productId }: { priceId: string; productId: string }) => {
    const { data, error } = await subscription.create({
      priceId,
      productId,
      successUrl: `${process.env.EXPO_PUBLIC_APP_URL}/membership`,
      cancelUrl: `${process.env.EXPO_PUBLIC_APP_URL}/membership?canceled=true`,
    })
    if (error) {
      Alert.alert('错误', '订阅创建失败')
      return
    }
    if (data?.url) await Linking.openURL(data.url)
  }

  const upgradeSubscription = async ({ credits }: { credits: number }) => {
    if (!activeAuthSubscription?.stripeSubscriptionId) {
      Alert.alert('错误', '未找到活跃订阅')
      return
    }
    const planIndex = creditPlans.findIndex(plan => plan.credits === credits)
    const planNames = stripePricingData?.pricing_table_items?.map((item: any) => item.product_name) || []
    const planName = planNames[planIndex] || 'basic'
    const { data, error } = await subscription.upgrade({
      plan: planName,
      subscriptionId: activeAuthSubscription.stripeSubscriptionId,
      successUrl: `${process.env.EXPO_PUBLIC_APP_URL}/membership`,
      cancelUrl: `${process.env.EXPO_PUBLIC_APP_URL}/membership?canceled=true`,
    })
    if (error) {
      Alert.alert('错误', '订阅升级失败')
      return
    }
  }

  const restoreSubscription = async () => {
    if (!activeAuthSubscription) {
      Alert.alert('错误', '未找到可恢复的订阅')
      return
    }
    const { data, error } = await subscription.restore({
      subscriptionId: activeAuthSubscription.stripeSubscriptionId,
      referenceId: activeAuthSubscription.referenceId,
    })
    if (error) {
      Alert.alert('错误', '订阅恢复失败')
      return
    }
    Alert.alert('成功', '订阅已恢复')
    await fetchAuthSubscriptions()
  }

  const cancelSubscription = async () => {
    if (!activeAuthSubscription) {
      Alert.alert('错误', '未找到活跃订阅')
      return
    }
    const { data, error } = await subscription.cancel({
      subscriptionId: activeAuthSubscription.stripeSubscriptionId,
      referenceId: activeAuthSubscription.referenceId,
    })
    if (error) {
      Alert.alert('错误', '订阅取消失败')
      return
    }
    Alert.alert('成功', '订阅已取消')
    await fetchAuthSubscriptions()
  }

  const rechargeToken = async (amount: number) => {
    if (!amount || amount <= 0) {
      Alert.alert('错误', '充值金额无效')
      return
    }
    if (!meteredSubscriptions?.[0]?.priceId) {
      Alert.alert('错误', '定价数据不可用')
      return
    }
    const { data, error } = await subscription.credit.topup({
      amount,
      priceId: meteredSubscriptions[0].priceId,
      successUrl: `${process.env.EXPO_PUBLIC_APP_URL}/membership`,
      cancelUrl: `${process.env.EXPO_PUBLIC_APP_URL}/membership?canceled=true`,
    })
    if (error) {
      Alert.alert('错误', '充值失败')
      return
    }
    if (data?.url) await Linking.openURL(data.url)
  }

  return {
    selectedPlanIndex,
    selectedPlan,
    creditPlans,
    stripePricingData,
    session,
    activeAuthSubscription,
    hasActiveSubscription,
    creditBalance,
    isLoadingSubscriptions,
    isStripePricingLoading,
    setSelectedPlanIndex,
    createSubscription,
    upgradeSubscription,
    restoreSubscription,
    cancelSubscription,
    rechargeToken,
    refetchAuthSubscriptions: fetchAuthSubscriptions,
  }
}