//  Copyright 2023 Harness, 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 validation

import (
	"net/url"
	"strings"
)

// IsValidURL checks if URL is valid.
func IsValidURL(uri string) bool {
	if u, err := url.ParseRequestURI(uri); err != nil ||
		(u.Scheme != "http" && u.Scheme != "https") ||
		!validPort(portOnly(u.Host)) {
		return false
	}

	return true
}

func validPort(p string) bool {
	for _, r := range []byte(p) {
		if r < '0' || r > '9' {
			return false
		}
	}
	return true
}

func portOnly(hostport string) string {
	colon := strings.IndexByte(hostport, ':')
	if colon == -1 {
		return ""
	}
	if i := strings.Index(hostport, "]:"); i != -1 {
		return hostport[i+len("]:"):]
	}
	if strings.Contains(hostport, "]") {
		return ""
	}
	return hostport[colon+len(":"):]
}