using System.Text;
using System.Text.RegularExpressions;

namespace ZA.CoreService.ESBCertificateManager.Services;

public sealed class RunLogger : IDisposable
{
    private static readonly Regex ConnectionStringSecretRegex = new(
        @"(Password|Pwd|Passwort)\s*=\s*[^;]+",
        RegexOptions.IgnoreCase | RegexOptions.Compiled);

    private static readonly Regex InlineSecretRegex = new(
        @"(Password|Pwd)\s*[:=]\s*\S+",
        RegexOptions.IgnoreCase | RegexOptions.Compiled);

    private readonly StreamWriter _writer;
    private readonly object _sync = new();
    public string LogFilePath { get; }

    public RunLogger(string logDirectory)
    {
        string directory = PathResolver.ResolvePath(logDirectory);
        Directory.CreateDirectory(directory);

        string fileName = $"run-{DateTime.Now:yyyyMMdd-HHmmss}.log";
        LogFilePath = Path.Combine(directory, fileName);

        _writer = new StreamWriter(LogFilePath, append: false, Encoding.UTF8)
        {
            AutoFlush = true
        };

        Write($"Run gestartet von {Environment.UserName} auf {Environment.MachineName}");
    }

    public void Write(string message)
    {
        string line = $"{DateTimeOffset.Now:yyyy-MM-dd HH:mm:ss.fff} | {Redact(message)}";
        lock (_sync)
        {
            _writer.WriteLine(line);
        }
    }

    public void Dispose()
    {
        lock (_sync)
        {
            _writer.Dispose();
        }
    }

    private static string Redact(string message)
    {
        if (string.IsNullOrEmpty(message))
        {
            return message;
        }

        // Keine Passwörter / Connection-Secrets in Logs.
        string redacted = ConnectionStringSecretRegex.Replace(message, "$1=***");
        return InlineSecretRegex.Replace(redacted, "$1=***");
    }
}