//
//  SDLConfiguration.swift
//  sdlan
//
//  Created by 安礼成 on 2025/7/14.
//
import Foundation
import NIOCore

// 配置项目
public class SDLConfiguration {
    public struct StunServer {
        public let host: String
        public let ports: [Int]
        
        public init(host: String, ports: [Int]) {
            self.host = host
            self.ports = ports
        }
    }
    
    public struct NetworkAddress {
        public let networkId: UInt32
        public let ip: UInt32
        public let maskLen: UInt8
        public let mac: Data
        public let networkDomain: String
    }
    
    // 当前的客户端版本
    let version: UInt8
    
    // 安装渠道
    let installedChannel: String
    
    let superHost: String
    let superPort: Int
    
    let stunServers: [StunServer]
    
    let remoteDnsServer: String
    let noticePort: Int
    
    lazy var stunSocketAddress: SocketAddress = {
        let stunServer = stunServers[0]
        return try! SocketAddress.makeAddressResolvingHost(stunServer.host, port: stunServer.ports[0])
    }()
    
    // 网络探测地址信息
    lazy var stunProbeSocketAddressArray: [[SocketAddress]] = {
        return stunServers.map { stunServer in
            [
                try! SocketAddress.makeAddressResolvingHost(stunServer.host, port: stunServer.ports[0]),
                try! SocketAddress.makeAddressResolvingHost(stunServer.host, port: stunServer.ports[1])
            ]
        }
    }()
    
    let clientId: String
    let networkAddress: NetworkAddress
    let hostname: String
    let accessToken: String

    public init(version: UInt8,
                installedChannel: String,
                superHost: String,
                superPort: Int,
                stunServers: [StunServer],
                clientId: String,
                networkAddress: NetworkAddress,
                hostname: String,
                noticePort: Int,
                accessToken: String,
                remoteDnsServer: String) {
        
        self.version = version
        self.installedChannel = installedChannel
        self.superHost = superHost
        self.superPort = superPort
        self.stunServers = stunServers
        self.clientId = clientId
        self.networkAddress = networkAddress
        self.noticePort = noticePort
        self.accessToken = accessToken
        self.remoteDnsServer = remoteDnsServer
        self.hostname = hostname
    }
    
    // 获取mac地址
    public static func getMacAddress() -> Data {
        let key = "gMacAddress2"
        
        let userDefaults = UserDefaults.standard
        if let mac = userDefaults.value(forKey: key) as? Data {
            return mac
        }
        else {
            let mac = generateMacAddress()
            userDefaults.setValue(mac, forKey: key)
            
            return mac
        }
    }
    
    // 随机生成mac地址
    private static func generateMacAddress() -> Data {
        var macAddress = [UInt8](repeating: 0, count: 6)
        for i in 0..<6 {
            macAddress[i] = UInt8.random(in: 0...255)
        }
        
        return Data(macAddress)
    }
    
}

// 解析配置文件
extension SDLConfiguration {
    
    static func parse(options: [String: NSObject]) -> SDLConfiguration? {
        guard let installed_channel = options["installed_channel"] as? String,
              let superIp = options["super_ip"] as? String,
              let superPort = options["super_port"] as? Int,
              let stunServersStr = options["stun_servers"] as? String,
              let noticePort = options["notice_port"] as? Int,
              let token = options["token"] as? String,
              let accessToken = options["access_token"] as? String,
              let clientId = options["client_id"] as? String,
              let remoteDnsServer = options["remote_dns_server"] as? String,
              let hostname = options["hostname"] as? String,
              let networkAddressDict = options["networkAddress"] as? [String: NSObject] else {
            return nil
        }

        guard let stunServers = parseStunServers(stunServersStr: stunServersStr), stunServers.count >= 2 else {
            NSLog("stunServers配置错误")
            return nil
        }
        
        guard let networkAddress = parseNetworkAddress(networkAddressDict) else {
            return nil
        }
        
        NSLog("[PacketTunnelProvider] client_id: \(clientId), token: \(token)")

        return SDLConfiguration(version: 1,
                                installedChannel: installed_channel,
                                superHost: superIp,
                                superPort: superPort,
                                stunServers: stunServers,
                                clientId: clientId,
                                networkAddress: networkAddress,
                                hostname: hostname,
                                noticePort: noticePort,
                                accessToken: accessToken,
                                remoteDnsServer: remoteDnsServer)
    }
    
    
    private static func parseStunServers(stunServersStr: String) -> [SDLConfiguration.StunServer]? {
        let stunServers = stunServersStr.split(separator: ";").compactMap { server -> SDLConfiguration.StunServer? in
            let parts = server.split(separator: ":", maxSplits: 2)
            guard parts.count == 2 else {
                return nil
            }
            
            let ports = parts[1].split(separator: ",", maxSplits: 2)
            guard ports.count == 2, let port1 = Int(String(ports[0])), let port2 = Int(String(ports[1])) else {
                return nil
            }
            
            return .init(host: String(parts[0]), ports: [port1, port2])
        }
        
        return stunServers.count >= 2 ? stunServers : nil
    }
    
    private static func parseNetworkAddress(_ config: [String: NSObject]) -> SDLConfiguration.NetworkAddress? {
        guard let networkId = config["network_id"] as? UInt32,
              let ipStr = config["ip"] as? String,
              let ip = SDLUtil.ipv4StrToInt32(ipStr),
              let maskLen = config["mask_len"] as? UInt8,
              let mac = config["mac"] as? Data,
              let networkDomain = config["network_domain"] as? String else {
            return nil
        }
        
        return .init(networkId: networkId, ip: ip, maskLen: maskLen, mac: mac, networkDomain: networkDomain)
    }
    
}