// Source: https://github.com/distribution/distribution

// Copyright 2014 https://github.com/distribution/distribution Authors
//
// 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 challenge

import (
	"net/url"
	"strings"
)

// FROM: https://golang.org/src/net/http/http.go
// Given a string of the form "host", "host:port", or "[ipv6::address]:port",
// return true if the string includes a port.
func hasPort(s string) bool { return strings.LastIndex(s, ":") > strings.LastIndex(s, "]") }

// FROM: http://golang.org/src/net/http/transport.go
var portMap = map[string]string{
	"http":  "80",
	"https": "443",
}

// canonicalAddr returns url.Host but always with a ":port" suffix
// FROM: http://golang.org/src/net/http/transport.go
func canonicalAddr(url *url.URL) string {
	addr := url.Host
	if !hasPort(addr) {
		return addr + ":" + portMap[url.Scheme]
	}
	return addr
}