const net = require('net');

class Ip {
    static async parseNetworkInfo(output) {
        // 初始化结果对象
        const result = {
            interface: '',
            flags: [],
            mtu: '',
            state: '',
            ipv6Addresses: []
        };

        // 按行分割输入
        const lines = output.split('\n').map(line => line.trim());

        // 解析第一行的基本信息
        if (lines.length > 0) {
            const firstLineParts = lines[0].split(/\s+/);
            // 提取接口名称
            result.interface = firstLineParts[1].replace(':', '');

            // 提取标志
            if (firstLineParts[2] && firstLineParts[2].startsWith('<') && firstLineParts[2].endsWith('>')) {
                result.flags = firstLineParts[2].slice(1, -1).split(',');
            }

            // 提取MTU
            const mtuIndex = firstLineParts.indexOf('mtu');
            if (mtuIndex !== -1 && mtuIndex + 1 < firstLineParts.length) {
                result.mtu = firstLineParts[mtuIndex + 1];
            }

            // 提取状态
            const stateIndex = firstLineParts.indexOf('state');
            if (stateIndex !== -1 && stateIndex + 1 < firstLineParts.length) {
                result.state = firstLineParts[stateIndex + 1];
            }
        }

        // 解析IPv6地址信息
        let currentIpv6 = null;
        for (let i = 1; i < lines.length; i++) {
            const line = lines[i];
            if (line.startsWith('inet6')) {
                // 如果有当前正在处理的IPv6地址，先保存
                if (currentIpv6) {
                    result.ipv6Addresses.push(currentIpv6);
                }

                // 开始解析新的IPv6地址
                const parts = line.split(/\s+/);
                const ipv6Address = parts[1].split("/")[0]
                currentIpv6 = {
                    local: ipv6Address.includes("fe80"),
                    connect: await Ip.checkIPv6WithTcp(ipv6Address),
                    address: ipv6Address,
                    scope: parts[2].replace('scope', ''),
                    properties: parts.slice(3),
                    validLft: '',
                    preferredLft: ''
                };
            } else if (currentIpv6 && line.includes('valid_lft')) {
                // 解析有效期信息
                const lftParts = line.split(/\s+/);
                currentIpv6.validLft = lftParts[0].replace('valid_lft', '');
                currentIpv6.preferredLft = lftParts[1].replace('preferred_lft', '');
            }
        }

        // 添加最后一个IPv6地址
        if (currentIpv6) {
            result.ipv6Addresses.push(currentIpv6);
        }

        return result;
    }

    /**
     * 检测IPv6地址是否可访问（通过尝试建立TCP连接）
     * @param {string} ipv6 - 要检测的IPv6地址
     * @param {number} port - 目标端口，默认 21100
     * @param {number} timeout - 超时时间（毫秒），默认1000
     * @returns {Promise<boolean>} - 是否可访问
    */
    static checkIPv6WithTcp(ipv6, port = 21100, timeout = 1000) {
        return new Promise((resolve) => {
            // 验证IPv6格式
            if (!net.isIPv6(ipv6)) {
                resolve(false);
                return;
            }

            const socket = new net.Socket({ family: 6 }); // 指定IPv6

            // 设置超时
            const timer = setTimeout(() => {
                socket.destroy();
                resolve(false);
            }, timeout);

            // 尝试连接
            socket.connect(port, ipv6, () => {
                clearTimeout(timer);
                socket.destroy();
                resolve(true);
            });

            // 错误处理
            socket.on('error', () => {
                clearTimeout(timer);
                resolve(false);
            });
        });
    }
}

module.exports = Ip