/*
 * MinIO Cloud Storage, (C) 2018 MinIO, 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 event

// RulesMap - map of rules for every event name.
type RulesMap map[Name]Rules

// add - adds event names, prefixes, suffixes and target ID to rules map.
func (rulesMap RulesMap) add(eventNames []Name, pattern string, targetID TargetID) {
	rules := make(Rules)
	rules.Add(pattern, targetID)

	for _, eventName := range eventNames {
		for _, name := range eventName.Expand() {
			rulesMap[name] = rulesMap[name].Union(rules)
		}
	}
}

// Clone - returns copy of this rules map.
func (rulesMap RulesMap) Clone() RulesMap {
	rulesMapCopy := make(RulesMap)

	for eventName, rules := range rulesMap {
		rulesMapCopy[eventName] = rules.Clone()
	}

	return rulesMapCopy
}

// Add - adds given rules map.
func (rulesMap RulesMap) Add(rulesMap2 RulesMap) {
	for eventName, rules := range rulesMap2 {
		rulesMap[eventName] = rules.Union(rulesMap[eventName])
	}
}

// Remove - removes given rules map.
func (rulesMap RulesMap) Remove(rulesMap2 RulesMap) {
	for eventName, rules := range rulesMap {
		if nr := rules.Difference(rulesMap2[eventName]); len(nr) != 0 {
			rulesMap[eventName] = nr
		} else {
			delete(rulesMap, eventName)
		}
	}
}

// Match - returns TargetIDSet matching object name and event name in rules map.
func (rulesMap RulesMap) Match(eventName Name, objectName string) TargetIDSet {
	return rulesMap[eventName].Match(objectName)
}

// NewRulesMap - creates new rules map with given values.
func NewRulesMap(eventNames []Name, pattern string, targetID TargetID) RulesMap {
	// If pattern is empty, add '*' wildcard to match all.
	if pattern == "" {
		pattern = "*"
	}

	rulesMap := make(RulesMap)
	rulesMap.add(eventNames, pattern, targetID)
	return rulesMap
}