Add project files.

ConfigurationPannel/Services/ConfigurationManager.cs

@@ -0,0 +1,61 @@
+using System.Text.Json;
+using Inspectron.Epson.PrintServer.ConfigurationSources;
+using Inspectron.Epson.PrintServer.PrintServices;
+
+namespace ConfigurationPannel.Services;
+
+public class ConfigurationManager
+{
+    private readonly string _configPath;
+    private readonly SemaphoreSlim _configLock = new SemaphoreSlim(1, 1);
+    private EpsonPrintServiceConfiguration? _currentConfig;
+
+    public ConfigurationManager(IWebHostEnvironment env)
+    {
+        _configPath = Path.Combine(env.ContentRootPath, "config.json");
+    }
+
+    public async Task<EpsonPrintServiceConfiguration> LoadConfigurationAsync()
+    {
+        await _configLock.WaitAsync();
+        try
+        {
+            if (File.Exists(_configPath))
+            {
+                var json = await File.ReadAllTextAsync(_configPath);
+                _currentConfig = JsonSerializer.Deserialize<EpsonPrintServiceConfiguration>(json);
+            }
+            else
+            {
+                _currentConfig = new EpsonPrintServiceConfiguration
+                {
+                    GroupId = "default-group",
+                    RestaurantId = "default-restaurant",
+                    PrinterConfigurations = new Dictionary<string, PrinterConfiguration>()
+                };
+            }
+            return _currentConfig!;
+        }
+        finally
+        {
+            _configLock.Release();
+        }
+    }
+
+    public async Task SaveConfigurationAsync(EpsonPrintServiceConfiguration config)
+    {
+        await _configLock.WaitAsync();
+        try
+        {
+            var json = JsonSerializer.Serialize(config, new JsonSerializerOptions { WriteIndented = true });
+            await File.WriteAllTextAsync(_configPath, json);
+            _currentConfig = config;
+        }
+        finally
+        {
+            _configLock.Release();
+        }
+    }
+
+    public EpsonPrintServiceConfiguration? GetCurrentConfiguration() => _currentConfig;
+}