import { ref } from 'vue'

interface UserinfoDto {
  username: string
  email: string
  roles: string[]
  exp: number
}

export class User {
  static readonly ANONYMOUS = new User('', '', [])

  constructor(
    readonly name: string,
    readonly email: string,
    readonly roles: string[]
  ) {}

  get isAuthenticated(): boolean {
    return !!this.name
  }

  hasAnyRole(...roles: string[]): boolean {
    for (const r of roles) {
      if (this.roles.includes(r)) {
        return true
      }
    }
    return false
  }
}

export class UserService {
  readonly current = ref(User.ANONYMOUS)
  private refreshIntervalId?: number

  constructor() {
    this.refresh()
  }

  async refresh(): Promise<void> {
    if (this.refreshIntervalId) {
      clearInterval(this.refreshIntervalId)
    }
    const response = await fetch(`/bff/api/me`)
    const user = (await response.json()) as UserinfoDto
    if (
      user?.username !== this.current?.value?.name ||
      user?.email !== this.current?.value?.email ||
      (user?.roles || []).toString() !== this.current?.value?.roles?.toString()
    ) {
      this.current.value = user?.username
        ? new User(user.username, user.email || '', user.roles || [])
        : User.ANONYMOUS
    }
    if (user?.exp) {
      const now = Date.now()
      const delay = (1000 * user.exp - now) * 0.8
      if (delay > 2000) {
        this.refreshIntervalId = setInterval(this.refresh, delay)
      }
    }
  }
}