using System;
using System.Collections.Generic;
using Dapper;
using MySql.Data.MySqlClient;
using log4net;

// 文件用途：从 CNC 系统配置表 cnc_sys_config 读取运行时配置，并覆盖默认 CollectorConfig 的设置
// 设计目标：在独立进程的采集服务中，不依赖仓储层，直接从数据库加载运行时参数
namespace CncCollector.Config
{
    /// <summary>
    /// 运行时配置加载器：从 cnc_sys_config 表读取配置，覆盖 CollectorConfig 的默认值
    /// </summary>
    public static class ConfigLoader
    {
        private static readonly ILog _log = LogManager.GetLogger(typeof(ConfigLoader));

        /// <summary>
        /// 从数据库加载运行时配置并覆盖给定的 CollectorConfig 实例的默认值。
        /// </summary>
        /// <param name="connectionString">MySQL/MariaDB 连接字符串</param>
        /// <param name="config">需要被覆盖的 CollectorConfig 实例（来自 CNC 采集服务）</param>
        public static void LoadRuntimeConfig(string connectionString, CncModels.Entity.CollectorConfig config)
        {
            if (string.IsNullOrWhiteSpace(connectionString))
            {
                _log.Warn("配置加载失败：连接字符串为空");
                return;
            }

            if (config == null)
            {
                _log.Warn("配置加载失败：传入的 CollectorConfig 为 null");
                return;
            }

            try
            {
                using (var conn = new MySqlConnection(connectionString))
                {
                    conn.Open();
                    // 需要加载的键集合
                    var keys = new[]
                    {
                        "collector_api_port",
                        "collector_api_key",
                        "heartbeat_interval",
                        "config_poll_interval",
                        "daily_summary_time",
                        "collect_retry_count",
                        "collect_retry_interval",
                        "collect_fail_alert_threshold"
                    };

                    foreach (var key in keys)
                    {
                        var value = conn.QueryFirstOrDefault<string>(
                            "SELECT config_value FROM cnc_sys_config WHERE config_key = @Key",
                            new { Key = key });
                        if (value == null) continue;
                        Apply(config, key, value);
                    }
                }
            }
            catch (Exception ex)
            {
                _log.Error("加载运行时配置异常", ex);
            }
        }

        private static void Apply(CncModels.Entity.CollectorConfig config, string key, string value)
        {
            try
            {
                switch (key)
                {
                    case "collector_api_port":
                        SetIntProperty(config, nameof(config.ApiPort), value);
                        break;
                    case "collector_api_key":
                        SetStringProperty(config, nameof(config.ApiKey), value);
                        break;
                    case "heartbeat_interval":
                        SetIntProperty(config, nameof(config.HeartbeatInterval), value);
                        break;
                    case "config_poll_interval":
                        SetIntProperty(config, nameof(config.ConfigPollInterval), value);
                        break;
                    case "daily_summary_time":
                        SetTimeSpanProperty(config, nameof(config.DailySummaryTime), value);
                        break;
                    case "collect_retry_count":
                        SetIntProperty(config, nameof(config.CollectRetryCount), value);
                        break;
                    case "collect_retry_interval":
                        SetIntProperty(config, nameof(config.CollectRetryIntervalSeconds), value);
                        break;
                    case "collect_fail_alert_threshold":
                        SetIntProperty(config, nameof(config.CollectFailAlertThreshold), value);
                        break;
                }
            }
            catch
            {
                // 忽略单项配置解析失败，继续加载其他配置
            }
        }

        private static void SetIntProperty(CncModels.Entity.CollectorConfig obj, string propName, string value)
        {
            if (obj == null) return;
            var p = obj.GetType().GetProperty(propName);
            if (p == null || !p.CanWrite) return;
            if (int.TryParse(value, out var v)) p.SetValue(obj, v);
        }

        private static void SetStringProperty(CncModels.Entity.CollectorConfig obj, string propName, string value)
        {
            if (obj == null) return;
            var p = obj.GetType().GetProperty(propName);
            if (p == null || !p.CanWrite) return;
            p.SetValue(obj, value);
        }

        private static void SetTimeSpanProperty(CncModels.Entity.CollectorConfig obj, string propName, string value)
        {
            if (obj == null) return;
            var p = obj.GetType().GetProperty(propName);
            if (p == null || !p.CanWrite) return;
            if (TimeSpan.TryParse(value, out var ts)) p.SetValue(obj, ts);
        }
    }
}