import type { User, UserRole, VerificationStatus } from "@/lib/types"
import { create } from "zustand"

interface NotificationPrefs {
  order: boolean
  community: boolean
  system: boolean
}

const defaultNotificationPrefs: NotificationPrefs = {
  order: true,
  community: true,
  system: false,
}

export type ThemePreference = "light" | "dark" | "system"

const STORAGE_KEY = "juwan-auth"

interface PersistedAuth {
  user: User
  currentRole: UserRole
  verifiedRoles: UserRole[]
  verificationStatus: Partial<Record<UserRole, VerificationStatus>>
  themePreference: ThemePreference
}

function loadPersisted(): PersistedAuth | null {
  try {
    const raw = localStorage.getItem(STORAGE_KEY)
    if (!raw) return null
    const parsed = JSON.parse(raw) as PersistedAuth
    if (!parsed.user?.id) return null
    return parsed
  } catch {
    return null
  }
}

function persist(state: PersistedAuth) {
  try {
    localStorage.setItem(STORAGE_KEY, JSON.stringify(state))
  } catch {}
}

function persistCurrent(state: AuthState) {
  if (!state.user) return
  persist({
    user: state.user,
    currentRole: state.currentRole,
    verifiedRoles: state.verifiedRoles,
    verificationStatus: state.verificationStatus,
    themePreference: state.themePreference,
  })
}

function clearPersisted() {
  try {
    localStorage.removeItem(STORAGE_KEY)
  } catch {}
}

const persisted = loadPersisted()

interface AuthState {
  isAuthenticated: boolean
  currentRole: UserRole
  verifiedRoles: UserRole[]
  verificationStatus: Partial<Record<UserRole, VerificationStatus>>
  verificationReasons: Partial<Record<UserRole, string>>
  notificationPrefs: NotificationPrefs
  themePreference: ThemePreference
  user: User | null
  switchRole: (role: UserRole) => void
  setNotificationPref: (type: keyof NotificationPrefs, enabled: boolean) => void
  setThemePreference: (theme: ThemePreference) => void
  updateProfile: (patch: { nickname?: string; bio?: string; avatar?: string }) => void
  login: (user: User, verifiedRoles?: UserRole[], themePreference?: ThemePreference) => void
  logout: () => void
}

export const useAuthStore = create<AuthState>((set, get) => ({
  isAuthenticated: persisted !== null,
  currentRole: persisted?.currentRole ?? "consumer",
  verifiedRoles: persisted?.verifiedRoles ?? ["consumer"],
  verificationStatus: persisted?.verificationStatus ?? { consumer: "approved" },
  verificationReasons: {},
  notificationPrefs: defaultNotificationPrefs,
  themePreference: persisted?.themePreference ?? "system",
  user: persisted?.user ?? null,
  switchRole: (role) => {
    const { verifiedRoles } = get()
    if (verifiedRoles.includes(role)) {
      set({ currentRole: role })
      persistCurrent(get())
    }
  },
  setNotificationPref: (type, enabled) =>
    set((state) => ({
      notificationPrefs: {
        ...state.notificationPrefs,
        [type]: enabled,
      },
    })),
  setThemePreference: (theme) => {
    set({ themePreference: theme })
    persistCurrent(get())
  },
  updateProfile: (patch) =>
    set((state) => {
      if (!state.user) return state
      const next = {
        ...state,
        user: {
          ...state.user,
          nickname: patch.nickname ?? state.user.nickname,
          bio: patch.bio ?? state.user.bio,
          avatar: patch.avatar ?? state.user.avatar,
        },
      }
      persistCurrent(next)
      return next
    }),
  login: (user, verifiedRoles, themePreference) =>
    set((state) => {
      const nextVerifiedRoles = verifiedRoles ?? user.verifiedRoles ?? [user.role]
      const nextVerificationStatus =
        user.verificationStatus ??
        nextVerifiedRoles.reduce<Partial<Record<UserRole, VerificationStatus>>>((acc, role) => {
          acc[role] = "approved"
          return acc
        }, {})

      const nextTheme = themePreference ?? state.themePreference

      persist({
        user,
        currentRole: user.role,
        verifiedRoles: nextVerifiedRoles,
        verificationStatus: nextVerificationStatus,
        themePreference: nextTheme,
      })

      return {
        isAuthenticated: true,
        user,
        currentRole: user.role,
        verifiedRoles: nextVerifiedRoles,
        verificationStatus: nextVerificationStatus,
        verificationReasons: {},
        notificationPrefs: state.notificationPrefs,
        themePreference: nextTheme,
      }
    }),
  logout: () => {
    clearPersisted()
    set({
      isAuthenticated: false,
      currentRole: "consumer",
      verifiedRoles: ["consumer"],
      verificationStatus: { consumer: "approved" },
      verificationReasons: {},
      notificationPrefs: defaultNotificationPrefs,
      themePreference: "system",
      user: null,
    })
  },
}))