/*
 * Copyright (c) 2020 Baidu, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package bce

// validator houses a set of rule needed for validation of a
// string value
type rules []rule

// rule interface allows for more flexible rules and just simply
// checks whether or not a value adheres to that rule
type rule interface {
	IsValid(value string) bool
}

// mapRule generic rule for maps
type mapRule map[string]struct{}

// IsValid for the map rule satisfies whether it exists in the map
func (m mapRule) IsValid(value string) bool {
	_, ok := m[value]
	return ok
}

// IsValid will iterate through all rules and see if any rules
// apply to the value and supports nested rules
func (r rules) IsValid(value string) bool {
	for _, rule := range r {
		if rule.IsValid(value) {
			return true
		}
	}
	return false
}

// blacklist is a generic rule for blacklisting
type blacklist struct {
	rule
}

// IsValid for blacklist checks if the value is within the blacklist
func (b blacklist) IsValid(value string) bool {
	return !b.rule.IsValid(value)
}
