'use client'

import { createContext, useContext, useState, useEffect, ReactNode, useCallback } from 'react'
import { api, clearTokens, getAccessToken, User, UserRole, LoginRequest, RegisterRequest } from '@/lib/api'

interface AuthState {
  user: User | null
  isAuthenticated: boolean
  isLoading: boolean
}

interface AuthContextType extends AuthState {
  login: (credentials: LoginRequest) => Promise<{ success: boolean; error?: string }>
  register: (data: RegisterRequest) => Promise<{ success: boolean; error?: string }>
  logout: () => void
  switchRole: (role: UserRole) => void
}

const AuthContext = createContext<AuthContextType | undefined>(undefined)

const USER_STORAGE_KEY = 'miaosi_user'

// 开发模式：使用 mock 数据
export const USE_MOCK = process.env.NEXT_PUBLIC_USE_MOCK === 'true' || process.env.NODE_ENV === 'development'

// Mock 用户数据
const MOCK_USERS: Record<string, User & { password: string }> = {
  'creator@demo.com': {
    id: 'user-001',
    name: '达人小美',
    email: 'creator@demo.com',
    role: 'creator',
    is_verified: true,
    creator_id: 'CR123456',
    tenant_id: 'BR001',
    tenant_name: '美妆品牌A',
    password: 'demo123',
  },
  'agency@demo.com': {
    id: 'user-002',
    name: '张经理',
    email: 'agency@demo.com',
    role: 'agency',
    is_verified: true,
    agency_id: 'AG123456',
    tenant_id: 'BR001',
    tenant_name: '美妆品牌A',
    password: 'demo123',
  },
  'brand@demo.com': {
    id: 'user-003',
    name: '李总监',
    email: 'brand@demo.com',
    role: 'brand',
    is_verified: true,
    brand_id: 'BR001',
    tenant_id: 'BR001',
    tenant_name: '美妆品牌A',
    password: 'demo123',
  },
}

export function AuthProvider({ children }: { children: ReactNode }) {
  const [user, setUser] = useState<User | null>(null)
  const [isLoading, setIsLoading] = useState(true)

  // 初始化时从 localStorage 恢复登录状态
  useEffect(() => {
    if (typeof window !== 'undefined') {
      // 检查是否有 token
      const token = getAccessToken()
      const storedUser = localStorage.getItem(USER_STORAGE_KEY)

      if (token && storedUser) {
        try {
          const parsed = JSON.parse(storedUser)
          setUser(parsed)
        } catch {
          clearTokens()
          localStorage.removeItem(USER_STORAGE_KEY)
        }
      }
    }
    setIsLoading(false)
  }, [])

  const login = useCallback(async (credentials: LoginRequest): Promise<{ success: boolean; error?: string }> => {
    try {
      if (USE_MOCK) {
        // Mock 登录
        await new Promise((resolve) => setTimeout(resolve, 500))
        const email = credentials.email || ''
        const mockUser = MOCK_USERS[email]
        if (!mockUser) {
          return { success: false, error: '用户不存在' }
        }
        // 验证码登录或密码登录
        if (credentials.email_code) {
          // 验证码登录 mock: 任何验证码都通过
        } else if (mockUser.password !== credentials.password) {
          return { success: false, error: '密码错误' }
        }
        const { password: _, ...userWithoutPassword } = mockUser
        setUser(userWithoutPassword)
        localStorage.setItem(USER_STORAGE_KEY, JSON.stringify(userWithoutPassword))
        return { success: true }
      }

      // 真实 API 登录
      const response = await api.login(credentials)
      setUser(response.user)
      localStorage.setItem(USER_STORAGE_KEY, JSON.stringify(response.user))
      return { success: true }
    } catch (err) {
      const error = err instanceof Error ? err.message : '登录失败'
      return { success: false, error }
    }
  }, [])

  const register = useCallback(async (data: RegisterRequest): Promise<{ success: boolean; error?: string }> => {
    try {
      if (USE_MOCK) {
        // Mock 注册（直接登录）
        await new Promise((resolve) => setTimeout(resolve, 500))
        const mockUser: User = {
          id: `user-${Date.now()}`,
          email: data.email,
          phone: data.phone,
          name: data.name,
          role: data.role,
          is_verified: false,
        }
        setUser(mockUser)
        localStorage.setItem(USER_STORAGE_KEY, JSON.stringify(mockUser))
        return { success: true }
      }

      // 真实 API 注册
      const response = await api.register(data)
      setUser(response.user)
      localStorage.setItem(USER_STORAGE_KEY, JSON.stringify(response.user))
      return { success: true }
    } catch (err) {
      const error = err instanceof Error ? err.message : '注册失败'
      return { success: false, error }
    }
  }, [])

  const logout = useCallback(() => {
    setUser(null)
    clearTokens()
    localStorage.removeItem(USER_STORAGE_KEY)
  }, [])

  const switchRole = useCallback((role: UserRole) => {
    if (user) {
      const updated = { ...user, role }
      setUser(updated)
      localStorage.setItem(USER_STORAGE_KEY, JSON.stringify(updated))
    }
  }, [user])

  return (
    <AuthContext.Provider
      value={{
        user,
        isAuthenticated: !!user,
        isLoading,
        login,
        register,
        logout,
        switchRole,
      }}
    >
      {children}
    </AuthContext.Provider>
  )
}

export function useAuth() {
  const context = useContext(AuthContext)
  if (context === undefined) {
    throw new Error('useAuth must be used within an AuthProvider')
  }
  return context
}