Initial commit: IBKRTrader

.NET WinForms-Anwendung (Core, Modules/CongressTrading, UI).
Enthaelt .gitignore und settings.example.json als Konfigurationsvorlage.
Echte settings.json mit Zugangsdaten ist bewusst ausgeschlossen.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Core/Database/DatabaseService.cs

@@ -0,0 +1,119 @@
+using Dapper;
+using MySqlConnector;
+using IBKRTrader.Core.Logging;
+using IBKRTrader.Core.Settings;
+
+namespace IBKRTrader.Core.Database;
+
+/// <summary>
+/// Zentraler Datenbankzugriff via MySqlConnector + Dapper.
+/// Jede Methode öffnet eine eigene Connection (Connection-Pooling via MySqlConnector).
+/// </summary>
+public class DatabaseService
+{
+    private readonly SettingsService _settings;
+    private readonly LoggingService  _logger;
+
+    public DatabaseService(SettingsService settings, LoggingService logger)
+    {
+        _settings = settings;
+        _logger   = logger;
+
+        // Dapper support for DateOnly
+        SqlMapper.AddTypeHandler(new DateOnlyTypeHandler());
+    }
+
+    private class DateOnlyTypeHandler : SqlMapper.TypeHandler<DateOnly>
+    {
+        public override void SetValue(System.Data.IDbDataParameter parameter, DateOnly value)
+        {
+            parameter.Value = value.ToString("yyyy-MM-dd");
+        }
+
+        public override DateOnly Parse(object value)
+        {
+            if (value is DateTime dt) return DateOnly.FromDateTime(dt);
+            if (value is string s && DateOnly.TryParse(s, out var d)) return d;
+            return DateOnly.FromDateTime(Convert.ToDateTime(value));
+        }
+    }
+
+
+    // ─── Connection ───────────────────────────────────────────────────────────
+
+    public MySqlConnection CreateConnection()
+        => new(_settings.Settings.Database.BuildConnectionString());
+
+    public async Task<bool> TestConnectionAsync()
+    {
+        try
+        {
+            await using var conn = CreateConnection();
+            await conn.OpenAsync();
+            _logger.Info("Core", "Datenbankverbindung erfolgreich hergestellt.");
+            return true;
+        }
+        catch (Exception ex)
+        {
+            _logger.Error("Core", "Datenbankverbindung fehlgeschlagen.", ex);
+            return false;
+        }
+    }
+
+    // ─── Abfragen (Dapper) ────────────────────────────────────────────────────
+
+    public async Task<IEnumerable<T>> QueryAsync<T>(string sql, object? param = null)
+    {
+        await using var conn = CreateConnection();
+        return await conn.QueryAsync<T>(sql, param);
+    }
+
+    public async Task<T?> QueryFirstOrDefaultAsync<T>(string sql, object? param = null)
+    {
+        await using var conn = CreateConnection();
+        return await conn.QueryFirstOrDefaultAsync<T>(sql, param);
+    }
+
+    public async Task<int> ExecuteAsync(string sql, object? param = null)
+    {
+        await using var conn = CreateConnection();
+        return await conn.ExecuteAsync(sql, param);
+    }
+
+    public async Task<T> ExecuteScalarAsync<T>(string sql, object? param = null)
+    {
+        await using var conn = CreateConnection();
+#pragma warning disable CS8603
+        return await conn.ExecuteScalarAsync<T>(sql, param);
+#pragma warning restore CS8603
+    }
+
+    // ─── Worker-Log Hilfsmethoden ─────────────────────────────────────────────
+
+    /// <summary>Legt einen neuen Worker-Log-Eintrag an und gibt die neue ID zurück.</summary>
+    public async Task<long> BeginWorkerLogAsync(string workerName, string module)
+    {
+        const string sql =
+            @"INSERT INTO `core_worker_log` (worker_name, module, started_at, status)
+              VALUES (@workerName, @module, @now, 'Running');
+              SELECT LAST_INSERT_ID();";
+        return await ExecuteScalarAsync<long>(sql,
+            new { workerName, module, now = DateTime.UtcNow });
+    }
+
+    /// <summary>Schließt einen Worker-Log-Eintrag ab (Success oder Error).</summary>
+    public async Task EndWorkerLogAsync(long logId, bool success, string? message = null)
+    {
+        const string sql =
+            @"UPDATE `core_worker_log`
+              SET finished_at = @now, status = @status, message = @msg
+              WHERE id = @id";
+        await ExecuteAsync(sql, new
+        {
+            id     = logId,
+            now    = DateTime.UtcNow,
+            status = success ? "Success" : "Error",
+            msg    = message
+        });
+    }
+}