import { computed, ref } from 'vue'
import { defineStore } from 'pinia'
import { z } from 'zod'

import { API_BASE } from '@/utils/apiBase'

export const authUserSchema = z.object({
  id: z.number().int().positive(),
  email: z.string().email(),
})

const meResponseSchema = z.object({
  user: authUserSchema,
})

const loginErrorResponseSchema = z.object({
  error: z.string(),
})

export type AuthUser = z.infer<typeof authUserSchema>
export type LoginFieldErrors = Partial<Record<'email' | 'password', string>>

export const useAuthStore = defineStore('auth', () => {
  const user = ref<AuthUser | null>(null)
  const loading = ref(false)
  const error = ref<string | null>(null)
  const isAuthenticated = computed(() => user.value !== null)

  async function fetchMe(): Promise<boolean> {
    loading.value = true
    error.value = null

    try {
      const response = await fetch(`${API_BASE}/api/me`, {
        method: 'GET',
        credentials: 'include',
        headers: {
          Accept: 'application/json',
        },
      })

      if (response.status === 200) {
        const responseBody: unknown = await response.json()
        user.value = meResponseSchema.parse(responseBody).user

        return true
      }

      user.value = null
      if (response.status !== 401) {
        error.value = 'Unable to restore session'
      }

      return false
    } catch {
      user.value = null
      error.value = 'Unable to restore session'

      return false
    } finally {
      loading.value = false
    }
  }

  async function login(email: string, password: string): Promise<boolean> {
    loading.value = true
    error.value = null

    try {
      const response = await fetch(`${API_BASE}/api/login`, {
        method: 'POST',
        credentials: 'include',
        headers: {
          Accept: 'application/json',
          'Content-Type': 'application/json',
        },
        body: JSON.stringify({ email, password }),
      })
      const responseBody: unknown = await response.json()

      if (response.status === 200) {
        user.value = meResponseSchema.parse(responseBody).user

        return true
      }

      user.value = null
      const errorResponse = loginErrorResponseSchema.safeParse(responseBody)
      error.value = errorResponse.success
        ? errorResponse.data.error
        : 'Unable to log in. Please try again.'

      return false
    } catch {
      user.value = null
      error.value = 'Unable to log in. Please try again.'

      return false
    } finally {
      loading.value = false
    }
  }

  async function logout(): Promise<void> {
    try {
      await fetch(`${API_BASE}/api/logout`, {
        method: 'POST',
        credentials: 'include',
        headers: {
          Accept: 'application/json',
        },
      })
    } finally {
      user.value = null
    }
  }

  return {
    user,
    loading,
    error,
    isAuthenticated,
    fetchMe,
    login,
    logout,
  }
})