"use client"

import { createContext, useContext, useState, useEffect, useCallback, type ReactNode } from "react"

interface User {
  id: string
  name: string
  email: string
  avatar?: string
  department: string
  role: "user" | "developer" | "admin"
  join_date: string
  favoriteApps: string[]
  recentApps: string[]
  total_likes: number
  total_views: number
  is_active: boolean
  last_login?: string
  phone?: string
  location?: string
  bio?: string
  created_at: string
  updated_at: string
}

interface AppLike {
  appId: string
  userId: string
  likedAt: string
}

interface AuthContextType {
  user: User | null
  login: (email: string, password: string) => Promise<boolean>
  register: (userData: RegisterData) => Promise<boolean>
  logout: () => void
  updateProfile: (userData: Partial<User>) => Promise<boolean>
  toggleFavorite: (appId: string) => Promise<boolean>
  isFavorite: (appId: string) => boolean
  addToRecentApps: (appId: string) => void
  getAppLikes: (appId: string) => number
  incrementViewCount: (appId: string) => void
  getViewCount: (appId: string) => number
  updateAppRating: (appId: string, rating: number) => void
  getAppRating: (appId: string) => number
  canSubmitApp: () => boolean
  canAccessAdmin: () => boolean
  isLoading: boolean
  isInitialized: boolean
  // New like functionality
  toggleLike: (appId: string) => Promise<boolean>
  isLiked: (appId: string) => boolean
  hasLikedToday: (appId: string) => boolean
  getAppLikesInPeriod: (appId: string, startDate: string, endDate: string) => number
  getUserLikeHistory: () => Array<{ appId: string; date: string }>
  getLikeCount: (appId: string) => number
  likeApp: (appId: string) => Promise<boolean>
}

interface RegisterData {
  name: string
  email: string
  password: string
  department: string
  role?: string
}

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

// Mock users data with new role system
const mockUsers: User[] = []

// Global app likes counter - in a real app this would be in a database
const appLikesCounter: Record<string, number> = {}

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

  // View count state with localStorage persistence
  const [appViews, setAppViews] = useState<Record<string, number>>(() => {
    if (typeof window !== "undefined") {
      const saved = localStorage.getItem("appViews")
      return saved ? JSON.parse(saved) : {}
    }
    return {}
  })

  // App ratings state with localStorage persistence
  const [appRatings, setAppRatings] = useState<Record<string, number>>(() => {
    if (typeof window !== "undefined") {
      const saved = localStorage.getItem("appRatings")
      return saved ? JSON.parse(saved) : {}
    }
    return {}
  })

  // App statistics state (from database)
  const [appStats, setAppStats] = useState<Record<string, {
    likesCount: number
    viewsCount: number
    rating: number
    reviewsCount: number
  }>>({})

  // User interaction states (from database) - 不使用 localStorage，總是從資料庫載入
  const [userLikes, setUserLikes] = useState<Record<string, string[]>>({})
  const [userFavorites, setUserFavorites] = useState<Record<string, string[]>>({})

  const [appLikes, setAppLikes] = useState<Record<string, AppLike[]>>(() => {
    if (typeof window !== "undefined") {
      const saved = localStorage.getItem("appLikes")
      return saved ? JSON.parse(saved) : {}
    }
    return {}
  })

  // New like system state with localStorage persistence
  const [userLikesOld, setUserLikesOld] = useState<Record<string, Array<{ appId: string; date: string }>>>(() => {
    if (typeof window !== "undefined") {
      const saved = localStorage.getItem("userLikes")
      return saved ? JSON.parse(saved) : {}
    }
    return {}
  })

  // App likes with date tracking
  const [appLikesOld, setAppLikesOld] = useState<Record<string, Array<{ userId: string; date: string }>>>(() => {
    if (typeof window !== "undefined") {
      const saved = localStorage.getItem("appLikesOld")
      return saved ? JSON.parse(saved) : {}
    }
    return {}
  })

  useEffect(() => {
    // Check for stored user session only on client side
    if (typeof window !== 'undefined') {
      const storedUser = localStorage.getItem("user")
      if (storedUser) {
        const userData = JSON.parse(storedUser)
        setUser(userData)
        // 立即載入用戶的互動狀態，不使用 localStorage
        fetchUserInteractions(userData.id)
      }
    }
    setIsLoading(false)
    setIsInitialized(true)
  }, [])

  // 當用戶登入時載入互動狀態
  useEffect(() => {
    if (user) {
      fetchUserInteractions(user.id)
    }
  }, [user])

  // Save old likes to localStorage when they change (保留舊系統的 localStorage)
  useEffect(() => {
    if (typeof window !== "undefined") {
      localStorage.setItem("appLikesOld", JSON.stringify(appLikesOld))
    }
  }, [appLikesOld])

  const login = async (email: string, password: string): Promise<boolean> => {
    setIsLoading(true)

    try {
      const response = await fetch('/api/auth/login', {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify({ email, password }),
      })

      const data = await response.json()

      if (data.success && data.user) {
        // 添加前端需要的額外字段
        const userWithExtras = {
          ...data.user,
          favoriteApps: [],
          recentApps: []
        }
        setUser(userWithExtras)
        localStorage.setItem("user", JSON.stringify(userWithExtras))
        
        // 載入用戶的互動狀態
        await fetchUserInteractions(data.user.id)
        
        setIsLoading(false)
        return true
      } else {
        setIsLoading(false)
        return false
      }
    } catch (error) {
      console.error('登入錯誤:', error)
      setIsLoading(false)
      return false
    }
  }

  const register = async (userData: RegisterData): Promise<boolean> => {
    setIsLoading(true)

    try {
      const response = await fetch('/api/auth/register', {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify(userData),
      })

      const data = await response.json()

      if (data.success && data.user) {
        // 添加前端需要的額外字段
        const userWithExtras = {
          ...data.user,
          favoriteApps: [],
          recentApps: []
        }
        setUser(userWithExtras)
        localStorage.setItem("user", JSON.stringify(userWithExtras))
        setIsLoading(false)
        return true
      } else {
        setIsLoading(false)
        return false
      }
    } catch (error) {
      console.error('註冊錯誤:', error)
      setIsLoading(false)
      return false
    }
  }

  const logout = () => {
    setUser(null)
    localStorage.removeItem("user")
  }

  const updateProfile = async (userData: Partial<User>): Promise<boolean> => {
    if (!user) return false

    setIsLoading(true)

    try {
      const response = await fetch('/api/auth/profile', {
        method: 'PUT',
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify({
          userId: user.id,
          ...userData
        }),
      })

      const data = await response.json()

      if (data.success && data.user) {
        // 保持前端需要的額外字段
        const userWithExtras = {
          ...data.user,
          favoriteApps: user.favoriteApps,
          recentApps: user.recentApps
        }
        setUser(userWithExtras)
        localStorage.setItem("user", JSON.stringify(userWithExtras))
        setIsLoading(false)
        return true
      } else {
        setIsLoading(false)
        return false
      }
    } catch (error) {
      console.error('更新資料錯誤:', error)
      setIsLoading(false)
      return false
    }
  }

  const toggleFavorite = async (appId: string): Promise<boolean> => {
    if (!user) return false

    try {
      const isFavorited = userFavorites[user.id]?.includes(appId) || false
      
      if (isFavorited) {
        // 移除收藏
        const response = await fetch(`/api/apps/${appId}/favorite?userId=${user.id}`, {
          method: 'DELETE'
        })

        if (response.ok) {
          const data = await response.json()
          if (data.success) {
            // 更新本地狀態
            setUserFavorites(prev => ({
              ...prev,
              [user.id]: (prev[user.id] || []).filter(id => id !== appId)
            }))
            
            // 更新用戶的 favoriteApps
            const updatedFavorites = user.favoriteApps.filter((id) => id !== appId)
            await updateProfile({
              favoriteApps: updatedFavorites,
            })
            
            return false
          }
        }
      } else {
        // 添加收藏
        const response = await fetch(`/api/apps/${appId}/favorite`, {
          method: 'POST',
          headers: {
            'Content-Type': 'application/json',
          },
          body: JSON.stringify({
            userId: user.id
          })
        })

        if (response.ok) {
          const data = await response.json()
          if (data.success) {
            // 更新本地狀態
            setUserFavorites(prev => ({
              ...prev,
              [user.id]: [...(prev[user.id] || []), appId]
            }))
            
            // 更新用戶的 favoriteApps
            const updatedFavorites = [...user.favoriteApps, appId]
            await updateProfile({
              favoriteApps: updatedFavorites,
            })
            
            return true
          }
        } else if (response.status === 409) {
          // 已經收藏過，更新本地狀態
          setUserFavorites(prev => ({
            ...prev,
            [user.id]: [...(prev[user.id] || []), appId]
          }))
          return true
        }
      }
    } catch (error) {
      console.error('切換收藏狀態錯誤:', error)
    }

    return false
  }

  const isFavorite = useCallback((appId: string): boolean => {
    if (!user) return false
    const userFavs = userFavorites[user.id] || []
    return userFavs.includes(appId)
  }, [user, userFavorites])

  const isLiked = useCallback((appId: string): boolean => {
    if (!user) return false
    const userLikedApps = userLikes[user.id] || []
    return userLikedApps.includes(appId)
  }, [user, userLikes])

  const addToRecentApps = (appId: string): void => {
    if (!user) return

    const updatedRecent = [appId, ...user.recentApps.filter((id) => id !== appId)].slice(0, 10)
    updateProfile({
      recentApps: updatedRecent,
    })
  }

  const getAppLikes = (appId: string): number => {
    return appStats[appId]?.likesCount || 0
  }

  // 從資料庫獲取應用統計數據
  const fetchAppStats = async (appId: string) => {
    try {
      const response = await fetch(`/api/apps/${appId}/interactions`)
      if (response.ok) {
        const data = await response.json()
        if (data.success) {
          setAppStats(prev => ({
            ...prev,
            [appId]: data.data
          }))
        }
      }
    } catch (error) {
      console.error('獲取應用統計數據錯誤:', error)
    }
  }

  // 從資料庫獲取用戶的按讚和收藏狀態
  const fetchUserInteractions = async (userId: string) => {
    try {
      const response = await fetch(`/api/user/interactions?userId=${userId}`)
      if (response.ok) {
        const data = await response.json()
        if (data.success) {
          setUserLikes(prev => ({ ...prev, [userId]: data.data.likes }))
          setUserFavorites(prev => ({ ...prev, [userId]: data.data.favorites }))
        }
      }
    } catch (error) {
      console.error('獲取用戶互動狀態錯誤:', error)
    }
  }

  // New like functionality
  const toggleLike = async (appId: string): Promise<boolean> => {
    if (!user) return false

    try {
      const response = await fetch(`/api/apps/${appId}/interactions`, {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify({
          action: 'like',
          userId: user.id
        })
      })

      if (response.ok) {
        const data = await response.json()
        if (data.success) {
          // 更新應用統計數據
          setAppStats(prev => ({
            ...prev,
            [appId]: data.data
          }))
          
          // 使用 API 返回的按讚狀態更新本地狀態
          const newLikedState = data.data.userLiked
          setUserLikes(prev => ({
            ...prev,
            [user.id]: newLikedState 
              ? [...(prev[user.id] || []), appId]
              : (prev[user.id] || []).filter(id => id !== appId)
          }))
          
          return newLikedState
        }
      }
    } catch (error) {
      console.error('切換按讚狀態錯誤:', error)
    }

    return false
  }

  const hasLikedTodayOld = (appId: string): boolean => {
    if (!user) return false

    const today = new Date().toISOString().split("T")[0]
    const userLikeHistory = userLikesOld[user.id] || []

    return userLikeHistory.some((like) => like.appId === appId && like.date === today)
  }

  const getAppLikesInPeriod = (appId: string, startDate: string, endDate: string): number => {
    const appLikeHistory = appLikesOld[appId] || []
    return appLikeHistory.filter((like) => {
      return like.date >= startDate && like.date <= endDate
    }).length
  }

  const getUserLikeHistory = (): Array<{ appId: string; date: string }> => {
    if (!user) return []
    return userLikesOld[user.id] || []
  }

  // View count functionality
  const incrementViewCount = async (appId: string): Promise<void> => {
    if (!user) return

    try {
      const response = await fetch(`/api/apps/${appId}/interactions`, {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
        },
        body: JSON.stringify({
          action: 'view',
          userId: user.id
        })
      })

      if (response.ok) {
        const data = await response.json()
        if (data.success) {
          setAppStats(prev => ({
            ...prev,
            [appId]: data.data
          }))
        }
      }
    } catch (error) {
      console.error('增加觀看次數錯誤:', error)
    }
  }

  const getViewCount = (appId: string): number => {
    return appStats[appId]?.viewsCount || 0
  }

  // Rating functionality
  const updateAppRating = (appId: string, rating: number): void => {
    setAppRatings((prev) => {
      const newRatings = { ...prev, [appId]: rating }
      if (typeof window !== "undefined") {
        localStorage.setItem("appRatings", JSON.stringify(newRatings))
      }
      return newRatings
    })
  }

  const getAppRating = (appId: string): number => {
    return appStats[appId]?.rating || 0
  }

  const getLikeCount = (appId: string): number => {
    return appLikes[appId]?.length || 0
  }

  const hasLikedToday = (appId: string): boolean => {
    if (!user) return false

    const today = new Date().toISOString().split("T")[0]
    return appLikes[appId]?.some((like) => like.userId === user.id && like.likedAt.startsWith(today)) || false
  }

  const likeApp = async (appId: string): Promise<boolean> => {
    if (!user) return false

    const today = new Date().toISOString().split("T")[0]

    // Check if user already liked today
    if (hasLikedToday(appId)) return false

    const newLike: AppLike = {
      appId,
      userId: user.id,
      likedAt: new Date().toISOString(),
    }

    setAppLikes((prev) => {
      const updatedLikes = { ...prev }
      if (!updatedLikes[appId]) {
        updatedLikes[appId] = []
      }
      updatedLikes[appId] = [...updatedLikes[appId], newLike]

      if (typeof window !== "undefined") {
        localStorage.setItem("appLikes", JSON.stringify(updatedLikes))
      }

      return updatedLikes
    })

    return true
  }

  // Permission check functions
  const canSubmitApp = (): boolean => {
    return user?.role === "developer"
  }

  const canAccessAdmin = (): boolean => {
    return user?.role === "admin"
  }


  return (
    <AuthContext.Provider
      value={{
        user,
        login,
        register,
        logout,
        updateProfile,
        toggleFavorite,
        isFavorite,
        addToRecentApps,
        getAppLikes,
        incrementViewCount,
        getViewCount,
        updateAppRating,
        getAppRating,
        canSubmitApp,
        canAccessAdmin,
        isLoading,
        isInitialized,
        // New like functionality
        toggleLike,
        isLiked,
        hasLikedTodayOld,
        getAppLikesInPeriod,
        getUserLikeHistory,
        getLikeCount,
        hasLikedToday,
        likeApp,
      }}
    >
      {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
}