initial commit

certmgr/Core/Converters/Impl/StorageConverter.cs

@@ -0,0 +1,121 @@
+using System.Diagnostics.CodeAnalysis;
+
+using CertMgr.Core.Log;
+using CertMgr.Core.Storage;
+
+namespace CertMgr.Core.Converters.Impl;
+
+internal sealed class StorageConverter : ValueConverter<IStorage>
+{
+    private const char Separator = '|';
+
+    protected override Task<IStorage?> DoConvertAsync(string rawValue, Type targetType, CancellationToken cancellationToken)
+    {
+        ReadOnlySpan<char> rawSpan = rawValue.AsSpan();
+
+        int storageTypeSplitIndex = rawSpan.IndexOf(Separator);
+        if (storageTypeSplitIndex == -1)
+        {
+            return Task.FromResult((IStorage?)EmptyStorage.Empty);
+        }
+
+        IStorage? storage;
+
+        ReadOnlySpan<char> storageTypeSpan = rawSpan.Slice(0, storageTypeSplitIndex);
+        ReadOnlySpan<char> storageDefinition = rawSpan.Slice(storageTypeSplitIndex + 1);
+        switch (storageTypeSpan)
+        {
+            case "file":
+                if (!TryGetFileStore(storageDefinition, out storage))
+                {
+                    storage = EmptyStorage.Empty;
+                }
+                break;
+            default:
+                storage = EmptyStorage.Empty;
+                break;
+        }
+
+        return Task.FromResult((IStorage?)storage);
+    }
+
+    private bool TryGetFileStore(ReadOnlySpan<char> storageDefinition, [NotNullWhen(true)] out IStorage? storage)
+    {
+        // expecting that 'storageDefinition' is something like:
+        // <store-mode>|<file-path>
+        //   or
+        // |<file-path>
+        //   or
+        // <file-path>
+        //
+        // where <store-mode> can be:
+        //   'o' or 'overwrite' or 'overwriteornew'
+        //     or
+        //   'a' or 'append' or 'appendornew'
+        //    or
+        //   'c' or 'create' or 'createnew'
+        //
+        // where <file-path> can be:
+        //   'c:\path\myfile.txt'
+        //     or
+        //   '/path/myfile.txt'
+        //     or
+        //  './path/myfile.txt'
+        //  in addition - <file-path> can be either quoted or double-quoted
+
+        storage = null;
+
+        FileStoreMode defaultStoreMode = FileStoreMode.OverwriteOrNew;
+        FileStoreMode storeMode;
+        ReadOnlySpan<char> filename;
+
+        int firstSplitIndex = storageDefinition.IndexOf(Separator);
+        if (firstSplitIndex != -1)
+        {
+            // there is a splitter. On the left side of it there must be <store-mode>. On the right there is a <file-path>
+
+            ReadOnlySpan<char> firstPart = storageDefinition.Slice(0, firstSplitIndex);
+            filename = storageDefinition.Slice(firstSplitIndex + 1);
+
+            if (firstPart.Length == 0)
+            {
+                storeMode = defaultStoreMode;
+            }
+            else if (Enum.TryParse(firstPart, true, out FileStoreMode tmpMode))
+            {
+                storeMode = tmpMode;
+            }
+            else if (firstPart.Equals("w", StringComparison.OrdinalIgnoreCase) || firstPart.Equals("overwrite", StringComparison.OrdinalIgnoreCase))
+            {
+                storeMode = FileStoreMode.OverwriteOrNew;
+            }
+            else if (firstPart.Equals("c", StringComparison.OrdinalIgnoreCase) || firstPart.Equals("createnew", StringComparison.OrdinalIgnoreCase))
+            {
+                storeMode = FileStoreMode.Create;
+            }
+            else if (firstPart.Equals("a", StringComparison.OrdinalIgnoreCase) || firstPart.Equals("append", StringComparison.OrdinalIgnoreCase))
+            {
+                storeMode = FileStoreMode.AppendOrNew;
+            }
+            else if (firstPart.Equals("o", StringComparison.OrdinalIgnoreCase) || firstPart.Equals("open", StringComparison.OrdinalIgnoreCase))
+            {
+                storeMode = FileStoreMode.Open;
+            }
+            else
+            {
+                // it is not store-mode or there is a typo or unsupported value
+                CLog.Error(string.Concat("Unsupported store-mode '", firstPart, "'"));
+                storeMode = defaultStoreMode;
+            }
+        }
+        else
+        {
+            // no split-char => just filename
+            storeMode = defaultStoreMode;
+            filename = storageDefinition;
+        }
+
+        storage = new FileStorage(filename.ToString(), storeMode);
+        return true;
+    }
+}