using System;
using System.Collections.Generic;
using UnityEngine;

/// <summary>
/// Android 网络配置器
/// 使用 Java 反射调用 Android WifiManager 和 DhcpInfo API 实现 DHCP/静态IP配置
/// 需要权限: android.permission.CHANGE_NETWORK_STATE, android.permission.ACCESS_WIFI_STATE, android.permission.CHANGE_WIFI_STATE
/// </summary>
#if UNITY_ANDROID && !UNITY_EDITOR
public static class AndroidNetworkConfigurator
{
    private static AndroidJavaObject _wifiManager;
    private static AndroidJavaObject _connectivityManager;
    private static AndroidJavaObject _currentActivity;
    private static AndroidJavaClass _unityPlayer;

    /// <summary>
    /// 初始化 Android 网络管理对象
    /// </summary>
    private static void Initialize()
    {
        try
        {
            if (_wifiManager != null) return;

            _unityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer");
            _currentActivity = _unityPlayer.GetStatic<AndroidJavaObject>("currentActivity");

            AndroidJavaObject context = _currentActivity.Call<AndroidJavaObject>("getApplicationContext");
            _wifiManager = context.Call<AndroidJavaObject>("getSystemService", "wifi");
            _connectivityManager = context.Call<AndroidJavaObject>("getSystemService", "connectivity");

            Debug.Log("[AndroidNetworkConfigurator] 初始化成功");
        }
        catch (Exception ex)
        {
            Debug.LogError($"[AndroidNetworkConfigurator] 初始化失败: {ex.Message}");
        }
    }

    /// <summary>
    /// 应用 DHCP 配置
    /// </summary>
    public static bool ApplyDhcp()
    {
        try
        {
            Initialize();

            if (_wifiManager == null)
            {
                Debug.LogError("[AndroidNetworkConfigurator] WifiManager 为空，无法应用 DHCP");
                return false;
            }

            // 获取 WifiManager.DhcpInfo
            AndroidJavaObject dhcpInfo = _wifiManager.Call<AndroidJavaObject>("getDhcpInfo");

            if (dhcpInfo == null)
            {
                Debug.LogWarning("[AndroidNetworkConfigurator] 无法获取 DhcpInfo");
                return false;
            }

            // 获取 WifiConfiguration
            AndroidJavaObject wifiConfig = GetCurrentWifiConfiguration();
            if (wifiConfig == null)
            {
                Debug.LogError("[AndroidNetworkConfigurator] 无法获取当前 WiFi 配置");
                return false;
            }

            // 清除静态IP配置，启用DHCP
            AndroidJavaClass ipAssignmentClass = new AndroidJavaClass("android.net.wifi.WifiConfiguration$IpAssignment");
            AndroidJavaObject dhcpAssignment = ipAssignmentClass.GetStatic<AndroidJavaObject>("DHCP");

            wifiConfig.Set("ipAssignment", dhcpAssignment);

            // 保存 WiFi 配置
            int networkId = _wifiManager.Call<int>("addNetwork", wifiConfig);
            if (networkId == -1)
            {
                // 尝试更新已有配置
                networkId = wifiConfig.Get<int>("networkId");
                _wifiManager.Call<bool>("updateNetwork", wifiConfig);
            }

            bool success = _wifiManager.Call<bool>("enableNetwork", networkId, true);
            
            if (success)
            {
                Debug.Log($"[AndroidNetworkConfigurator] DHCP 配置已应用，NetworkId: {networkId}");
            }
            else
            {
                Debug.LogWarning($"[AndroidNetworkConfigurator] DHCP 配置应用失败");
            }

            return success;
        }
        catch (Exception ex)
        {
            Debug.LogError($"[AndroidNetworkConfigurator] 应用 DHCP 异常: {ex.Message}\n{ex.StackTrace}");
            return false;
        }
    }

    /// <summary>
    /// 应用静态 IP 配置
    /// </summary>
    public static bool ApplyStaticIP(string ipAddress, string netmask, string gateway, string dns1, string dns2 = null)
    {
        try
        {
            Initialize();

            if (_wifiManager == null)
            {
                Debug.LogError("[AndroidNetworkConfigurator] WifiManager 为空，无法应用静态 IP");
                return false;
            }

            if (string.IsNullOrWhiteSpace(ipAddress) || string.IsNullOrWhiteSpace(netmask))
            {
                Debug.LogError("[AndroidNetworkConfigurator] IP 或子网掩码不能为空");
                return false;
            }

            // 获取当前 WiFi 配置
            AndroidJavaObject wifiConfig = GetCurrentWifiConfiguration();
            if (wifiConfig == null)
            {
                Debug.LogError("[AndroidNetworkConfigurator] 无法获取当前 WiFi 配置");
                return false;
            }

            // 设置IP分配方式为静态
            AndroidJavaClass ipAssignmentClass = new AndroidJavaClass("android.net.wifi.WifiConfiguration$IpAssignment");
            AndroidJavaObject staticAssignment = ipAssignmentClass.GetStatic<AndroidJavaObject>("STATIC");
            wifiConfig.Set("ipAssignment", staticAssignment);

            // 创建 StaticIpConfiguration 对象
            AndroidJavaObject staticIpConfig = CreateStaticIpConfiguration(ipAddress, netmask, gateway, dns1, dns2);
            wifiConfig.Set("staticIpConfiguration", staticIpConfig);

            // 保存 WiFi 配置
            int networkId = _wifiManager.Call<int>("addNetwork", wifiConfig);
            if (networkId == -1)
            {
                networkId = wifiConfig.Get<int>("networkId");
                _wifiManager.Call<bool>("updateNetwork", wifiConfig);
            }

            bool success = _wifiManager.Call<bool>("enableNetwork", networkId, true);

            if (success)
            {
                Debug.Log($"[AndroidNetworkConfigurator] 静态 IP 配置已应用\n" +
                    $"  IP: {ipAddress}\n" +
                    $"  Mask: {netmask}\n" +
                    $"  Gateway: {gateway}\n" +
                    $"  DNS1: {dns1}\n" +
                    $"  DNS2: {(dns2 ?? "无")}\n" +
                    $"  NetworkId: {networkId}");
            }
            else
            {
                Debug.LogWarning($"[AndroidNetworkConfigurator] 静态 IP 配置应用失败");
            }

            return success;
        }
        catch (Exception ex)
        {
            Debug.LogError($"[AndroidNetworkConfigurator] 应用静态 IP 异常: {ex.Message}\n{ex.StackTrace}");
            return false;
        }
    }

    /// <summary>
    /// 获取当前连接的 WiFi 配置
    /// </summary>
    private static AndroidJavaObject GetCurrentWifiConfiguration()
    {
        try
        {
            // 获取连接信息
            AndroidJavaObject connectionInfo = _wifiManager.Call<AndroidJavaObject>("getConnectionInfo");
            if (connectionInfo == null)
            {
                Debug.LogWarning("[AndroidNetworkConfigurator] 未连接到任何 WiFi");
                return null;
            }

            int networkId = connectionInfo.Call<int>("getNetworkId");
            Debug.Log($"[AndroidNetworkConfigurator] 当前 NetworkId: {networkId}");

            // 获取已配置的网络列表
            AndroidJavaObject configList = _wifiManager.Call<AndroidJavaObject>("getConfiguredNetworks");
            if (configList == null)
            {
                Debug.LogError("[AndroidNetworkConfigurator] 无法获取配置列表");
                return null;
            }

            // 遍历找到当前连接的配置
            AndroidJavaClass listClass = new AndroidJavaClass("java.util.List");
            int size = configList.Call<int>("size");

            for (int i = 0; i < size; i++)
            {
                AndroidJavaObject config = configList.Call<AndroidJavaObject>("get", i);
                int cfgNetworkId = config.Get<int>("networkId");

                if (cfgNetworkId == networkId)
                {
                    return config;
                }
            }

            // 如果没找到，创建新的配置
            Debug.LogWarning("[AndroidNetworkConfigurator] 未找到现有配置，创建新配置");
            AndroidJavaObject newConfig = new AndroidJavaObject("android.net.wifi.WifiConfiguration");
            newConfig.Set("networkId", networkId);
            return newConfig;
        }
        catch (Exception ex)
        {
            Debug.LogError($"[AndroidNetworkConfigurator] 获取 WiFi 配置异常: {ex.Message}");
            return null;
        }
    }

    /// <summary>
    /// 创建 StaticIpConfiguration 对象
    /// </summary>
    private static AndroidJavaObject CreateStaticIpConfiguration(string ipAddress, string netmask, string gateway, string dns1, string dns2)
    {
        try
        {
            AndroidJavaObject staticIpConfig = new AndroidJavaObject("android.net.StaticIpConfiguration");

            // 设置 IP 地址
            AndroidJavaObject ipAddr = CreateInetAddress(ipAddress);
            int prefixLength = MaskToPrefixLength(netmask);
            AndroidJavaObject linkAddress = new AndroidJavaObject("android.net.LinkAddress", ipAddr, prefixLength);
            staticIpConfig.Call("addIpAddress", linkAddress);

            // 设置网关
            if (!string.IsNullOrWhiteSpace(gateway))
            {
                AndroidJavaObject gatewayAddr = CreateInetAddress(gateway);
                staticIpConfig.Set("gateway", gatewayAddr);
            }

            // 添加 DNS 服务器
            AndroidJavaClass inetAddressClass = new AndroidJavaClass("java.net.InetAddress");
            AndroidJavaObject dnsCollection = staticIpConfig.Get<AndroidJavaObject>("dnsServers");

            if (!string.IsNullOrWhiteSpace(dns1))
            {
                AndroidJavaObject dns1Addr = CreateInetAddress(dns1);
                dnsCollection.Call<bool>("add", dns1Addr);
                Debug.Log($"[AndroidNetworkConfigurator] 添加 DNS1: {dns1}");
            }

            if (!string.IsNullOrWhiteSpace(dns2))
            {
                AndroidJavaObject dns2Addr = CreateInetAddress(dns2);
                dnsCollection.Call<bool>("add", dns2Addr);
                Debug.Log($"[AndroidNetworkConfigurator] 添加 DNS2: {dns2}");
            }

            return staticIpConfig;
        }
        catch (Exception ex)
        {
            Debug.LogError($"[AndroidNetworkConfigurator] 创建 StaticIpConfiguration 异常: {ex.Message}");
            return null;
        }
    }

    /// <summary>
    /// 根据 IP 地址字符串创建 InetAddress 对象
    /// </summary>
    private static AndroidJavaObject CreateInetAddress(string ipAddress)
    {
        try
        {
            AndroidJavaClass inetAddressClass = new AndroidJavaClass("java.net.InetAddress");
            return inetAddressClass.CallStatic<AndroidJavaObject>("getByName", ipAddress);
        }
        catch (Exception ex)
        {
            Debug.LogError($"[AndroidNetworkConfigurator] 创建 InetAddress '{ipAddress}' 异常: {ex.Message}");
            return null;
        }
    }

    /// <summary>
    /// 将子网掩码转换为前缀长度（CIDR）
    /// </summary>
    private static int MaskToPrefixLength(string netmask)
    {
        try
        {
            string[] parts = netmask.Split('.');
            if (parts.Length != 4)
            {
                Debug.LogWarning($"[AndroidNetworkConfigurator] 无效的子网掩码: {netmask}");
                return 24; // 默认 /24
            }

            int maskValue = 0;
            for (int i = 0; i < 4; i++)
            {
                if (int.TryParse(parts[i], out int octet))
                {
                    maskValue = (maskValue << 8) | octet;
                }
            }

            // 计算前缀长度
            int prefixLength = 0;
            uint mask = 0x80000000;
            for (int i = 0; i < 32; i++)
            {
                if ((maskValue & mask) == mask)
                {
                    prefixLength++;
                    mask >>= 1;
                }
                else
                {
                    break;
                }
            }

            Debug.Log($"[AndroidNetworkConfigurator] 子网掩码 {netmask} → 前缀长度 {prefixLength}");
            return prefixLength;
        }
        catch (Exception ex)
        {
            Debug.LogError($"[AndroidNetworkConfigurator] 转换掩码异常: {ex.Message}");
            return 24;
        }
    }

    /// <summary>
    /// 获取当前 IP 配置信息
    /// </summary>
    public static Dictionary<string, string> GetCurrentIPConfiguration()
    {
        var config = new Dictionary<string, string>();

        try
        {
            Initialize();

            if (_wifiManager == null)
            {
                config["status"] = "error";
                config["message"] = "WifiManager 为空";
                return config;
            }

            AndroidJavaObject connectionInfo = _wifiManager.Call<AndroidJavaObject>("getConnectionInfo");
            AndroidJavaObject dhcpInfo = _wifiManager.Call<AndroidJavaObject>("getDhcpInfo");

            if (connectionInfo != null)
            {
                int ipInt = connectionInfo.Call<int>("getIpAddress");
                string ip = FormatIPAddress(ipInt);
                config["current_ip"] = ip;

                string ssid = connectionInfo.Call<string>("getSSID");
                config["ssid"] = ssid ?? "未知";
            }

            if (dhcpInfo != null)
            {
                int ipInt = dhcpInfo.Get<int>("ipAddress");
                string ip = FormatIPAddress(ipInt);
                config["dhcp_ip"] = ip;

                int maskInt = dhcpInfo.Get<int>("netmask");
                string mask = FormatIPAddress(maskInt);
                config["dhcp_mask"] = mask;

                int gatewayInt = dhcpInfo.Get<int>("gateway");
                string gateway = FormatIPAddress(gatewayInt);
                config["dhcp_gateway"] = gateway;

                int dns1Int = dhcpInfo.Get<int>("dns1");
                string dns1 = FormatIPAddress(dns1Int);
                config["dhcp_dns1"] = dns1;

                int dns2Int = dhcpInfo.Get<int>("dns2");
                string dns2 = FormatIPAddress(dns2Int);
                config["dhcp_dns2"] = dns2;
            }

            config["status"] = "success";
            return config;
        }
        catch (Exception ex)
        {
            config["status"] = "error";
            config["message"] = ex.Message;
            Debug.LogError($"[AndroidNetworkConfigurator] 获取 IP 配置异常: {ex.Message}");
            return config;
        }
    }

    /// <summary>
    /// 格式化整数 IP 地址为点分十进制
    /// </summary>
    private static string FormatIPAddress(int ipInt)
    {
        return $"{(ipInt & 0xff)}.{((ipInt >> 8) & 0xff)}.{((ipInt >> 16) & 0xff)}.{((ipInt >> 24) & 0xff)}";
    }
}
#endif