using System;
using System.IO;
using System.Text;

namespace KellyReport_D.Utils
{
    internal static class FileLogger
    {
        private static readonly object _sync = new object();
        private static string LogDirectory =>
            Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "KellyReport", "logs");

        private static string GetLogFilePath()
        {
            string fileName = $"kellyreport_{DateTime.Now:yyyyMMdd}.log";
            return Path.Combine(LogDirectory, fileName);
        }

        private static void WriteInternal(string level, string message, Exception ex = null)
        {
            try
            {
                lock (_sync)
                {
                    Directory.CreateDirectory(LogDirectory);
                    var path = GetLogFilePath();
                    using (var sw = new StreamWriter(path, true, Encoding.UTF8))
                    {
                        sw.WriteLine($"{DateTime.Now:yyyy-MM-dd HH:mm:ss.fff} [{level}] {message}");
                        if (ex != null)
                        {
                            sw.WriteLine(ex.ToString());
                        }
                    }
                }
            }
            catch
            {
                // 日志写入不应影响主流程，忽略任何异常
            }
        }

        public static void Info(string message) => WriteInternal("INFO", message);
        public static void Debug(string message) => WriteInternal("DEBUG", message);
        public static void Error(string message, Exception ex = null) => WriteInternal("ERROR", message, ex);
    }
}