templates support

Inspectron.Epson.Templates/Storage/FileTemplateStorage.cs

@@ -0,0 +1,91 @@
+using System.Collections.Concurrent;
+
+namespace Inspectron.Epson.Templates.Storage;
+
+public class FileTemplateStorage : ITemplateStorage
+{
+    private readonly string _basePath;
+    private readonly string _templateExtension;
+    private readonly ConcurrentDictionary<string, string> _cache = new();
+
+    public FileTemplateStorage(string basePath, string templateExtension = ".template")
+    {
+        _basePath = Path.GetFullPath(basePath);
+        _templateExtension = templateExtension;
+
+        if (!Directory.Exists(_basePath))
+        {
+            Directory.CreateDirectory(_basePath);
+        }
+    }
+
+    public string? Load(string templatePath)
+    {
+        var normalizedPath = NormalizePath(templatePath);
+
+        if (_cache.TryGetValue(normalizedPath, out var cached))
+        {
+            return cached;
+        }
+
+        var fullPath = GetFullPath(normalizedPath);
+        if (!File.Exists(fullPath))
+        {
+            return null;
+        }
+
+        var content = File.ReadAllText(fullPath);
+        _cache[normalizedPath] = content;
+        return content;
+    }
+
+    public bool Exists(string templatePath)
+    {
+        var normalizedPath = NormalizePath(templatePath);
+        var fullPath = GetFullPath(normalizedPath);
+        return File.Exists(fullPath);
+    }
+
+    public void Reload()
+    {
+        _cache.Clear();
+    }
+
+    public IEnumerable<string> ListTemplates()
+    {
+        if (!Directory.Exists(_basePath))
+        {
+            yield break;
+        }
+
+        var files = Directory.GetFiles(_basePath, $"*{_templateExtension}", SearchOption.AllDirectories);
+        foreach (var file in files)
+        {
+            var relativePath = Path.GetRelativePath(_basePath, file);
+            yield return relativePath.Replace('\\', '/');
+        }
+    }
+
+    private string NormalizePath(string path)
+    {
+        // Ensure the path has the correct extension
+        if (!path.EndsWith(_templateExtension, StringComparison.OrdinalIgnoreCase))
+        {
+            path += _templateExtension;
+        }
+
+        // Normalize path separators
+        return path.Replace('\\', '/');
+    }
+
+    private string GetFullPath(string normalizedPath)
+    {
+        // Security: prevent directory traversal
+        var fullPath = Path.GetFullPath(Path.Combine(_basePath, normalizedPath));
+        if (!fullPath.StartsWith(_basePath, StringComparison.OrdinalIgnoreCase))
+        {
+            throw new InvalidOperationException($"Invalid template path: {normalizedPath}");
+        }
+        return fullPath;
+    }
+}