import { defineStore } from 'pinia'
import api from '../api'

const TOKEN_KEY = 'sg-access-token'
const REFRESH_KEY = 'sg-refresh-token'
const USER_KEY = 'sg-user'

function readUser() {
  try {
    const raw = localStorage.getItem(USER_KEY)
    return raw ? JSON.parse(raw) : null
  } catch {
    return null
  }
}

function persistSession({ access, refresh, user }) {
  if (access) localStorage.setItem(TOKEN_KEY, access)
  if (refresh) localStorage.setItem(REFRESH_KEY, refresh)
  if (user) localStorage.setItem(USER_KEY, JSON.stringify(user))
}

function clearSessionStorage() {
  localStorage.removeItem(TOKEN_KEY)
  localStorage.removeItem(REFRESH_KEY)
  localStorage.removeItem(USER_KEY)
}

export const useAuthStore = defineStore('auth', {
  state: () => ({
    accessToken: localStorage.getItem(TOKEN_KEY) || '',
    refreshToken: localStorage.getItem(REFRESH_KEY) || '',
    user: readUser(),
  }),

  getters: {
    isAuthenticated: (state) => Boolean(state.accessToken),
    username: (state) => state.user?.username || '',
    userId: (state) => state.user?.id ?? null,
  },

  actions: {
    setSession({ access, refresh, user }) {
      this.accessToken = access || ''
      this.refreshToken = refresh || ''
      this.user = user || null
      persistSession({ access, refresh, user })
    },

    async register({ username, email, password }) {
      const { data } = await api.post('/v1/auth/register/', {
        username: username.trim(),
        email: (email || '').trim(),
        password,
      })
      this.setSession(data)
      return data
    },

    async login({ username, password }) {
      const { data } = await api.post('/v1/auth/token/', {
        username: username.trim(),
        password,
      })
      this.setSession({
        access: data.access,
        refresh: data.refresh,
        user: { username: username.trim() },
      })
      await this.fetchMe()
      return data
    },

    async fetchMe() {
      const { data } = await api.get('/v1/auth/me/')
      this.user = data
      localStorage.setItem(USER_KEY, JSON.stringify(data))
      return data
    },

    async updateProfile({ username, email, currentPassword }) {
      const payload = { current_password: currentPassword }
      if (username !== undefined) payload.username = username.trim()
      if (email !== undefined) payload.email = (email || '').trim()
      const { data } = await api.patch('/v1/auth/me/', payload)
      this.user = data
      localStorage.setItem(USER_KEY, JSON.stringify(data))
      return data
    },

    async changePassword({ currentPassword, newPassword }) {
      const { data } = await api.post('/v1/auth/me/password/', {
        current_password: currentPassword,
        new_password: newPassword,
      })
      return data
    },

    logout() {
      this.accessToken = ''
      this.refreshToken = ''
      this.user = null
      clearSessionStorage()
    },
  },
})

export function getStoredAccessToken() {
  return localStorage.getItem(TOKEN_KEY) || ''
}

export function getStoredRefreshToken() {
  return localStorage.getItem(REFRESH_KEY) || ''
}

export function setStoredAccessToken(token) {
  if (token) {
    localStorage.setItem(TOKEN_KEY, token)
  } else {
    localStorage.removeItem(TOKEN_KEY)
  }
}

export function clearAuthStorage() {
  clearSessionStorage()
}