using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
using LightGlue.Unity.Config;
using UnityEngine;

namespace LightGlue.Unity.Roma
{
    /// <summary>
    /// OrangePi WiFi 图传控制（JSON over UDP，端口默认 8008）。
    /// 参考：orangepizero2w/UDP_PROTOCOL.md、上位机参考.md
    /// </summary>
    public sealed class RomaWifiCameraControlClient : MonoBehaviour
    {
        [Header("Device")]
        [Tooltip("设备IP（从广播发现获取后写入）")]
        public string deviceIp = "";

        [Tooltip("设备控制端口（固定 8008）")]
        public int deviceControlPort = 8008;

        [Header("Target (PC / Python)")]
        [Tooltip("图像流目标IP（通常是本机IP，不要用127.0.0.1）")]
        public string targetIp = "";

        [Tooltip("图像流目标端口（Python WiFi 图传接收端口）。注意不要填 12345（广播端口）")]
        public int targetPort = 9000;

        [Header("Behavior")]
        [Tooltip("发现设备IP后，是否自动发送 config + stream_on")]
        public bool autoConfigAndStartOnDeviceDiscovered = false;

        [Tooltip("若启用自动下发，是否由 RomaNetworkConfigUIController 统一执行（确保使用 localTargetIpField）。建议保持 true。")]
        public bool autoConfigHandledByUi = true;

        [Tooltip("当 targetIp 为空或为 127.0.0.1 时，是否自动填充为本机网卡 IP（用于下发给设备）。")]
        public bool autoFillTargetIpIfEmpty = true;

        [Tooltip("发送 config 后等待的毫秒数（给设备一点应用时间）")]
        public int delayMsBetweenConfigAndOn = 30;

        public event Action<string, int> OnConfigSent;
        public event Action OnStreamOnSent;

        private UdpClient _client;
        private IPEndPoint _deviceEp;

        private void OnEnable()
        {
            EnsureClient();
        }

        private void OnDisable()
        {
            try { _client?.Close(); } catch { /* ignore */ }
            try { _client?.Dispose(); } catch { /* ignore */ }
            _client = null;
            _deviceEp = null;
        }

        public void BindDiscovery(RomaDeviceDiscoveryListener discovery)
        {
            if (discovery == null) return;
            discovery.OnDeviceIpDiscovered -= HandleDeviceDiscovered;
            discovery.OnDeviceIpDiscovered += HandleDeviceDiscovered;
        }

        private void HandleDeviceDiscovered(string ip)
        {
            deviceIp = ip;
            Debug.Log($"[RomaWiFiCtrl] Device discovered: {deviceIp}");
            if (!autoConfigAndStartOnDeviceDiscovered) return;
            if (autoConfigHandledByUi) return;

            if (autoFillTargetIpIfEmpty && (string.IsNullOrWhiteSpace(targetIp) || targetIp.Trim() == "127.0.0.1"))
            {
                string localIp = NetworkConfig.GetLocalBindIp();
                if (!string.IsNullOrWhiteSpace(localIp) && localIp != "127.0.0.1")
                {
                    targetIp = localIp;
                    Debug.Log($"[RomaWiFiCtrl] Auto filled targetIp: {targetIp}");
                }
                else
                {
                    Debug.LogWarning("[RomaWiFiCtrl] targetIp 为空/127.0.0.1，且未能获取有效本机IP；将不会自动下发 config，请在 UI 中填写本机IP 后再发送。");
                    return;
                }
            }

            ConfigStream(targetIp, targetPort);
            if (delayMsBetweenConfigAndOn > 0)
            {
                Invoke(nameof(StartStream), delayMsBetweenConfigAndOn / 1000f);
            }
            else
            {
                StartStream();
            }
        }

        public void ConfigStream(string newTargetIp, int newTargetPort)
        {
            // 允许在配置时自动补齐本机IP，避免 Validate 直接失败导致用户误以为“没发送”
            if (autoFillTargetIpIfEmpty && (string.IsNullOrWhiteSpace(targetIp) || targetIp.Trim() == "127.0.0.1"))
            {
                string localIp = NetworkConfig.GetLocalBindIp();
                if (!string.IsNullOrWhiteSpace(localIp) && localIp != "127.0.0.1")
                    targetIp = localIp;
            }

            if (!Validate()) return;

            if (!string.IsNullOrWhiteSpace(newTargetIp))
                targetIp = newTargetIp.Trim();
            if (newTargetPort > 0)
                targetPort = newTargetPort;

            string json = $"{{\"type\":\"config\",\"data\":{{\"target_ip\":\"{targetIp}\",\"target_port\":{targetPort}}}}}";
            SendJson(json);
            Debug.Log($"[RomaWiFiCtrl] Sent config: target={targetIp}:{targetPort}");
            OnConfigSent?.Invoke(targetIp, targetPort);
        }

        public void StartStream()
        {
            if (!Validate()) return;
            SendJson("{\"type\":\"stream_on\",\"data\":{}}");
            Debug.Log("[RomaWiFiCtrl] Sent stream_on");
            OnStreamOnSent?.Invoke();
        }

        public void StopStream()
        {
            if (!Validate()) return;
            SendJson("{\"type\":\"stream_off\",\"data\":{}}");
            Debug.Log("[RomaWiFiCtrl] Sent stream_off");
        }

        private void SendJson(string json)
        {
            EnsureClient();
            if (_client == null) return;

            try
            {
                _deviceEp = new IPEndPoint(IPAddress.Parse(deviceIp), deviceControlPort);
                byte[] payload = Encoding.UTF8.GetBytes(json);
                _client.Send(payload, payload.Length, _deviceEp);
            }
            catch (Exception ex)
            {
                Debug.LogWarning($"[RomaWiFiCtrl] Send failed: {ex.Message}");
            }
        }

        private bool Validate()
        {
            if (string.IsNullOrWhiteSpace(deviceIp))
            {
                Debug.LogWarning("[RomaWiFiCtrl] deviceIp 为空（尚未发现设备）");
                return false;
            }
            if (deviceControlPort <= 0 || deviceControlPort > 65535)
            {
                Debug.LogWarning($"[RomaWiFiCtrl] deviceControlPort 无效: {deviceControlPort}");
                return false;
            }
            if (string.IsNullOrWhiteSpace(targetIp))
            {
                Debug.LogWarning("[RomaWiFiCtrl] targetIp 为空（请填写本机IP）");
                return false;
            }
            if (targetPort <= 0 || targetPort > 65535)
            {
                Debug.LogWarning($"[RomaWiFiCtrl] targetPort 无效: {targetPort}");
                return false;
            }
            if (targetPort == 12345)
            {
                Debug.LogWarning("[RomaWiFiCtrl] targetPort=12345 是广播端口，建议不要用（会冲突/混乱）。请改为 9000 或其他端口。");
            }
            return true;
        }

        private void EnsureClient()
        {
            if (_client != null) return;
            try
            {
                _client = new UdpClient();
            }
            catch (Exception ex)
            {
                Debug.LogError($"[RomaWiFiCtrl] Create UdpClient failed: {ex.Message}");
                _client = null;
            }
        }
    }
}