// Copyright 2025 The Casdoor Authors. All Rights Reserved.
//
// 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 util

import (
	"fmt"
	"net"
	"net/http"
	"os"
	"strings"
	"time"
)

func GetHostname() string {
	name, err := os.Hostname()
	if err != nil {
		panic(err)
	}

	return name
}

func IsInternetIp(ip string) bool {
	ipStr, _, err := net.SplitHostPort(ip)
	if err != nil {
		ipStr = ip
	}

	parsedIP := net.ParseIP(ipStr)
	if parsedIP == nil {
		return false
	}

	return !parsedIP.IsPrivate() && !parsedIP.IsLoopback() && !parsedIP.IsMulticast() && !parsedIP.IsUnspecified()
}

func IsHostIntranet(ip string) bool {
	ipStr, _, err := net.SplitHostPort(ip)
	if err != nil {
		ipStr = ip
	}

	parsedIP := net.ParseIP(ipStr)
	if parsedIP == nil {
		return false
	}

	return parsedIP.IsPrivate() || parsedIP.IsLoopback() || parsedIP.IsLinkLocalUnicast() || parsedIP.IsLinkLocalMulticast()
}

func ResolveDomainToIp(domain string) string {
	ips, err := net.LookupIP(domain)
	if err != nil {
		if strings.Contains(err.Error(), "no such host") {
			return "(empty)"
		}

		fmt.Printf("resolveDomainToIp() error: %s\n", err.Error())
		return err.Error()
	}

	for _, ip := range ips {
		if ipv4 := ip.To4(); ipv4 != nil {
			return ipv4.String()
		}
	}
	return "(empty)"
}

func PingUrl(url string) (bool, string) {
	client := http.Client{
		Timeout: 5 * time.Second,
	}
	resp, err := client.Get(url)
	if err != nil {
		return false, err.Error()
	}
	defer resp.Body.Close()

	if resp.StatusCode >= 200 && resp.StatusCode <= 299 {
		return true, ""
	}
	return false, fmt.Sprintf("Status: %s", resp.Status)
}

func IsIntranetIp(ip string) bool {
	ipStr, _, err := net.SplitHostPort(ip)
	if err != nil {
		ipStr = ip
	}

	parsedIP := net.ParseIP(ipStr)
	if parsedIP == nil {
		return false
	}

	return parsedIP.IsPrivate() ||
		parsedIP.IsLoopback() ||
		parsedIP.IsLinkLocalUnicast() ||
		parsedIP.IsLinkLocalMulticast()
}