Move DevDrive project to repo root

2026-01-05 07:19:06 +11:00
parent 9bf318e41e
commit 9fcad874b9
9 changed files with 8 additions and 0 deletions
--- a/FloppyStorage.cs
+++ b/FloppyStorage.cs
@@ -0,0 +1,213 @@
+using System.Collections.Concurrent;
+
+namespace DevDrive;
+
+/// <summary>
+/// Manages the in-memory file system storage for the virtual drive.
+/// </summary>
+public class FloppyStorage
+{
+    public const long DefaultCapacity = 1_474_560;
+    public const int SectorSize = 512;
+    public const int AllocationUnitSize = 512;
+
+    private readonly ConcurrentDictionary<string, FloppyFileNode> _files = new(StringComparer.OrdinalIgnoreCase);
+    private readonly object _lock = new();
+
+    public long Capacity { get; }
+    public long FreeSpace { get; }
+
+    public FloppyStorage() : this(DefaultCapacity, DefaultCapacity)
+    {
+    }
+
+    public FloppyStorage(long totalBytes, long freeBytes)
+    {
+        Capacity = totalBytes;
+        FreeSpace = freeBytes;
+        var root = new FloppyFileNode("\\", true);
+        _files["\\"] = root;
+    }
+
+    public FloppyFileNode? CreateSymlink(string path, string targetPath, bool isDirectory)
+    {
+        path = NormalizePath(path);
+
+        if (_files.ContainsKey(path))
+        {
+            return null;
+        }
+
+        var parentPath = GetParentPath(path);
+        if (!_files.ContainsKey(parentPath))
+        {
+            return null;
+        }
+
+        var node = new FloppyFileNode(path, isDirectory)
+        {
+            SymlinkTarget = targetPath,
+            Attributes = (isDirectory ? FileAttributes.Directory : FileAttributes.Normal) | FileAttributes.ReparsePoint
+        };
+        _files[path] = node;
+        return node;
+    }
+
+    public static string NormalizePath(string path)
+    {
+        if (string.IsNullOrEmpty(path))
+        {
+            return "\\";
+        }
+
+        path = path.Replace('/', '\\');
+        if (!path.StartsWith('\\'))
+        {
+            path = "\\" + path;
+        }
+
+        while (path.Contains("\\\\"))
+        {
+            path = path.Replace("\\\\", "\\");
+        }
+
+        if (path.Length > 1 && path.EndsWith('\\'))
+        {
+            path = path.TrimEnd('\\');
+        }
+
+        return path;
+    }
+
+    public static string GetParentPath(string path)
+    {
+        path = NormalizePath(path);
+        if (path == "\\")
+        {
+            return "\\";
+        }
+
+        var lastSlash = path.LastIndexOf('\\');
+        return lastSlash <= 0 ? "\\" : path[..lastSlash];
+    }
+
+    public bool Exists(string path)
+    {
+        path = NormalizePath(path);
+        return _files.ContainsKey(path);
+    }
+
+    public FloppyFileNode? GetNode(string path)
+    {
+        path = NormalizePath(path);
+        _files.TryGetValue(path, out var node);
+        return node;
+    }
+
+    public FloppyFileNode? CreateNode(string path, bool isDirectory)
+    {
+        path = NormalizePath(path);
+
+        if (_files.ContainsKey(path))
+        {
+            return _files[path];
+        }
+
+        var parentPath = GetParentPath(path);
+        if (!_files.ContainsKey(parentPath))
+        {
+            return null;
+        }
+
+        var node = new FloppyFileNode(path, isDirectory);
+        _files[path] = node;
+        return node;
+    }
+
+    public bool DeleteNode(string path)
+    {
+        path = NormalizePath(path);
+
+        if (path == "\\")
+        {
+            return false;
+        }
+
+        var node = GetNode(path);
+        if (node == null)
+        {
+            return false;
+        }
+
+        if (node.IsDirectory)
+        {
+            var children = GetChildren(path);
+            if (children.Any())
+            {
+                return false;
+            }
+        }
+
+        return _files.TryRemove(path, out _);
+    }
+
+    public IEnumerable<FloppyFileNode> GetChildren(string path)
+    {
+        path = NormalizePath(path);
+
+        foreach (var kvp in _files)
+        {
+            var filePath = kvp.Key;
+            if (filePath == path)
+            {
+                continue;
+            }
+
+            var parentPath = GetParentPath(filePath);
+            if (string.Equals(parentPath, path, StringComparison.OrdinalIgnoreCase))
+            {
+                yield return kvp.Value;
+            }
+        }
+    }
+
+    public bool MoveNode(string oldPath, string newPath, bool replace)
+    {
+        oldPath = NormalizePath(oldPath);
+        newPath = NormalizePath(newPath);
+
+        if (!_files.TryGetValue(oldPath, out var node))
+        {
+            return false;
+        }
+
+        if (_files.ContainsKey(newPath))
+        {
+            if (!replace)
+            {
+                return false;
+            }
+            _files.TryRemove(newPath, out _);
+        }
+
+        var newParentPath = GetParentPath(newPath);
+        if (!_files.ContainsKey(newParentPath))
+        {
+            return false;
+        }
+
+        _files.TryRemove(oldPath, out _);
+
+        node.FullPath = newPath;
+        node.Name = Path.GetFileName(newPath);
+        node.LastWriteTime = DateTime.Now;
+
+        _files[newPath] = node;
+        return true;
+    }
+
+    public bool HasEnoughSpace(long additionalBytes)
+    {
+        return FreeSpace >= additionalBytes;
+    }
+}