from guardian.admin import GuardedModelAdmin
from guardian.shortcuts import get_objects_for_user, assign_perm, remove_perm, get_users_with_perms,   get_groups_with_perms
  
# 需改前
@admin.register(DataAssistantJob)
class DataAssistantJobAdmin(admin.ModelAdmin):
  pass

# 修改后
@admin.register(DataAssistantJob)
class DataAssistantJobAdmin(GuardedModelAdmin):
  # app是否在主页面中显示的话由该函数决定
  def has_module_permission(self, request):
    if super().has_module_permission(request):
      return True
    return self.get_model_objs(request).exists()

  # 在显示数据列表额时候，哪些数据显示，哪些不显示，由该函数控制
  def get_queryset(self, request):
    if request.user.is_superuser:
      return super().get_queryset(request)

    data = self.get_model_objs(request)
    return data
    
  # 内部用来获取某个用户有权限访问的数据行
  def get_model_objs(self, request, action=None, klass=None):
    opts = self.opts
    actions = [action] if action else ['view', 'change', 'delete']
    klass = klass if klass else opts.model
    model_name = klass._meta.model_name
    return get_objects_for_user(user=request.user, perms=[f'{perm}_{model_name}' for perm in actions],
                  klass=klass, any_perm=True)

  # 用来判断某个用户是否有某个数据行的权限
  def has_perm(self, request, obj, action):
    opts = self.opts
    codename = f'{action}_{opts.model_name}'
    if obj:
      return request.user.has_perm(f'{opts.app_label}.{codename}', obj)
    else:
      return self.get_model_objs(request, action).exists()

  # 是否有查看某个数据行的权限
  def has_view_permission(self, request, obj=None):
    return self.has_perm(request, obj, 'view')

  # 是否有修改某个数据行的权限
  def has_change_permission(self, request, obj=None):
    return self.has_perm(request, obj, 'change')

  # 是否有删除某个数据行的权限
  def has_delete_permission(self, request, obj=None):
    return self.has_perm(request, obj, 'delete')

  # 用户应该拥有他新增的数据行的所有权限
  def save_model(self, request, obj, form, change):
    result = super().save_model(request, obj, form, change)
    if not request.user.is_superuser and not change:
      opts = self.opts
      actions = ['view', 'add', 'change', 'delete']
      [assign_perm(f'{opts.app_label}.{action}_{opts.model_name}', request.user, obj) for action in actions]
    return result