class implementation_check_kind_file_timestamp(interface_check_kind):

	'''
	[implementation]
	'''
	def parameters_schema(self):
		return {
			"type": "object",
			"additionalProperties": False,
			"properties": {
				"path": {
					"type": "string"
				},
				"warning_age": {
					"type": "integer",
					"exclusiveMinimum": 0,
					"default": (60 * 60)
				},
				"critical_age": {
					"type": "integer",
					"exclusiveMinimum": 0,
					"default": (60 * 60 * 24)
				},
				"condition_on_missing": {
					"description": "which condition to report if file is missing",
					"type": "string",
					"enum": [
						"unknown",
						"ok",
						"warning",
						"critical"
					],
					"default": "warning"
				},
				"condition_on_implausible": {
					"description": "which condition to report if the age is negative, i.e. the file is apparently from the future",
					"type": "string",
					"enum": [
						"unknown",
						"ok",
						"warning",
						"critical"
					],
					"default": "warning"
				}
			},
			"required": [
				"path"
			]
		}
		
	
	'''
	[implementation]
	'''
	def normalize_conf_node(self, node):
		if ("path" not in node):
			raise ValueError("missing mandatory field 'path'")
		else:
			return dict_merge(
				{
					"warning_age": (60 * 60),
					"critical_age": (60 * 60 * 24),
					"condition_on_missing": condition_encode(enum_condition.warning),
					"condition_on_implausible": condition_encode(enum_condition.warning),
				},
				node
			)
		
	
	'''
	[implementation]
	'''
	def run(self, parameters):
		if (not _os.path.exists(parameters["path"])):
			return {
				"condition": condition_decode(parameters["condition_on_missing"]),
				"output": "file is missing"
			}
		else:
			result = _os.stat(parameters["path"])
			timestamp = get_current_timestamp()
			age = (timestamp - result.st_atime)
			if (age < 0):
				return {
					"condition": condition_decode(parameters["condition_on_implausible"]),
					"output": string_coin(
						"file is apparently from the future; timestamp of checking instance: {{timestamp_this}}; timestamp of file: {{timestamp_that}} (age in seconds: {{age}})",
						{
							"timestamp_this": timestamp,
							"timestamp_that": result.st_atime,
							"age": ("%u" % age),
						}
					),
				}
			else:
				if ((age > 0) and (age <= parameters["warning_age"])):
					condition = enum_condition.ok
				elif ((age > parameters["warning_age"]) and (age <= parameters["critical_age"])):
					condition = enum_condition.warning
				elif (age > parameters["critical_age"]):
					condition = enum_condition.critical
				else:
					raise ValueError("impossible state")
				return {
					"condition": condition,
					"output": string_coin(
						"age in seconds: {{age}}",
						{
							"age": ("%u" % age),
						}
					),
				}