package device

import (
	"fmt"
	"network-topology-discovery/pkg/models"
	"regexp"
	"strings"
)

// LinuxParser Linux服务器解析器
type LinuxParser struct {
	BaseParser
}

// GetCommands 获取Linux命令列表
func (p *LinuxParser) GetCommands() []string {
	return []string{
		"hostname",
		"uname -a",
		"ip addr show",
		"ip link show",
		"uptime",
	}
}

// Parse 解析Linux输出
func (p *LinuxParser) Parse(device *models.Device, outputs []string) error {
	if len(outputs) < 5 {
		return fmt.Errorf("insufficient command outputs")
	}

	device.Hostname = strings.TrimSpace(outputs[0])
	device.OSVersion = p.parseOSVersion(outputs[1])
	device.Uptime = strings.TrimSpace(outputs[4])
	device.Interfaces = p.parseInterfaces(outputs[2], outputs[3])

	return nil
}

func (p *LinuxParser) parseOSVersion(output string) string {
	// 从uname提取内核版本
	parts := strings.Fields(output)
	if len(parts) >= 3 {
		return fmt.Sprintf("Linux %s", parts[2])
	}
	return output
}

func (p *LinuxParser) parseInterfaces(addrOutput, linkOutput string) []models.Interface {
	var interfaces []models.Interface

	// 解析ip addr show输出
	interfaceMap := make(map[string]*models.Interface)
	var currentInterface *models.Interface

	lines := strings.Split(addrOutput, "\n")
	for _, line := range lines {
		// 匹配接口: 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500
		if nameRegex := regexp.MustCompile(`^\d+:\s+(\S+):\s+<([^>]*)>`); nameRegex.MatchString(line) {
			matches := nameRegex.FindStringSubmatch(line)
			name := strings.TrimSuffix(matches[1], ":")
			flags := matches[2]

			currentInterface = &models.Interface{
				Name:   name,
				Status: "down",
			}

			if strings.Contains(flags, "UP") {
				currentInterface.Status = "up"
			}

			// 提取MTU
			if mtuRegex := regexp.MustCompile(`mtu\s+(\d+)`); mtuRegex.MatchString(line) {
				matches := mtuRegex.FindStringSubmatch(line)
				currentInterface.MTU = 0
				fmt.Sscanf(matches[1], "%d", &currentInterface.MTU)
			}

			interfaceMap[name] = currentInterface
			interfaces = append(interfaces, *currentInterface)
		}

		if currentInterface != nil {
			// 提取MAC地址
			if macRegex := regexp.MustCompile(`link/ether\s+(\S+)`); macRegex.MatchString(line) {
				matches := macRegex.FindStringSubmatch(line)
				currentInterface.MAC = matches[1]
			}

			// 提取IP地址
			if ipRegex := regexp.MustCompile(`inet\s+(\d+\.\d+\.\d+\.\d+)/(\d+)`); ipRegex.MatchString(line) {
				matches := ipRegex.FindStringSubmatch(line)
				currentInterface.IP = matches[1]
				currentInterface.Mask = matches[2]
			}
		}
	}

	// 更新接口列表
	finalInterfaces := make([]models.Interface, 0, len(interfaceMap))
	for _, iface := range interfaceMap {
		finalInterfaces = append(finalInterfaces, *iface)
	}

	return finalInterfaces
}