using System;
using System.Text;

namespace TeamAAS.Communication.LightSources
{
    /// <summary>
    /// TSD 光源协议命令构造器
    /// 适用于 DPA12024V-4T-3.0 等型号
    /// 特点: 所有命令带 XOR 校验字
    /// </summary>
    public static class TSDLightProtocol
    {
        /// <summary>
        /// 读取指定通道亮度
        /// #4{CH}00015 + XOR校验
        /// </summary>
        public static string BuildReadCommand(int channelIndex)
        {
            string cmd = $"#4{channelIndex + 1}00015";
            return cmd + CalcXor(cmd);
        }

        /// <summary>
        /// 设置指定通道亮度
        /// #3{CH}0{HEX} + XOR校验
        /// </summary>
        public static string BuildSetBrightnessCommand(int channelIndex, int brightness)
        {
            int br = Math.Max(0, Math.Min(255, brightness));
            string cmd = $"#3{channelIndex + 1}0{br.ToString("X2")}";
            return cmd + CalcXor(cmd);
        }

        /// <summary>
        /// 打开指定通道
        /// #1{CH}064 + XOR校验
        /// </summary>
        public static string BuildTurnOnChannelCommand(int channelIndex)
        {
            string cmd = $"#1{channelIndex + 1}064";
            return cmd + CalcXor(cmd);
        }

        /// <summary>
        /// 关闭指定通道
        /// #2{CH}029 + XOR校验
        /// </summary>
        public static string BuildTurnOffChannelCommand(int channelIndex)
        {
            string cmd = $"#2{channelIndex + 1}029";
            return cmd + CalcXor(cmd);
        }

        /// <summary>
        /// 全开所有通道（逐通道发送）
        /// </summary>
        public static string[] BuildTurnOnAllCommands(int channelCount)
        {
            var cmds = new string[channelCount];
            for (int i = 0; i < channelCount; i++)
                cmds[i] = BuildTurnOnChannelCommand(i);
            return cmds;
        }

        /// <summary>
        /// 全关所有通道（逐通道发送）
        /// </summary>
        public static string[] BuildTurnOffAllCommands(int channelCount)
        {
            var cmds = new string[channelCount];
            for (int i = 0; i < channelCount; i++)
                cmds[i] = BuildTurnOffChannelCommand(i);
            return cmds;
        }

        /// <summary>
        /// 解析读取响应，返回亮度值（16进制转10进制）
        /// </summary>
        public static int ParseReadResponse(string response)
        {
            if (string.IsNullOrEmpty(response)) return 0;
            if (response.Contains("$")) return 0;
            try
            {
                string val = response.Substring(4, 2);
                return Convert.ToInt32(val, 16);
            }
            catch { return 0; }
        }

        /// <summary>
        /// 验证响应是否成功
        /// 成功: 响应包含 "#"
        /// 失败: 响应包含 "$"
        /// </summary>
        public static bool VerifyResponse(string response)
        {
            return !string.IsNullOrEmpty(response) && response.Contains("#");
        }

        /// <summary>
        /// XOR 校验字计算
        /// </summary>
        public static string CalcXor(string asciiData)
        {
            if (string.IsNullOrEmpty(asciiData)) return "00";
            byte[] data = Encoding.ASCII.GetBytes(asciiData);
            byte xor = data[0];
            for (int i = 1; i < data.Length; i++)
                xor ^= data[i];

            char high = NibbleToAscii((byte)((xor >> 4) & 0x0F));
            char low = NibbleToAscii((byte)(xor & 0x0F));
            return new string(new[] { high, low });
        }

        private static char NibbleToAscii(byte nibble)
        {
            return nibble < 10 ? (char)('0' + nibble) : (char)('A' + (nibble - 10));
        }
    }
}