static public void AddRoot (FileModel root)
{
if (! root.IsRoot)
throw new Exception ("Attempted to add non-root as root");
roots.Add (root);
}
//////////////////////////////////////////////////////////////
// Useful utility functions
static private string PickName (FileModel p)
{
string pick;
do {
pick = Token.GetRandom ();
} while (p.children.Contains (pick));
return pick;
}
// If the move would cause a filename collision or is
// otherwise impossible, return false. Return true if the
// move actually happens.
public bool MoveTo (FileModel new_parent, // or null, to just rename
string new_name) // or null, to just move
{
if (! new_parent.IsDirectory)
throw new ArgumentException ("Parent must be a directory");
if (this.IsRoot)
throw new ArgumentException ("Can't move a root");
// Impossible
if (this == new_parent || this.IsAbove (new_parent))
return false;
string old_path;
old_path = this.FullName;
if (new_parent == null)
new_parent = this.parent;
if (new_name == null)
new_name = this.name;
// check for a filename collision
if (new_parent.children.Contains (new_name))
return false;
// modify the data structure
this.parent.children.Remove (this.name);
this.parent = new_parent;
this.name = new_name;
this.parent.children [this.name] = this;
string new_path;
new_path = Path.Combine (new_parent.FullName, new_name);
if (this.IsDirectory)
Directory.Move (old_path, new_path);
else
File.Move (old_path, new_path);
return true;
}
public void Delete ()
{
if (IsRoot)
throw new Exception ("Can't delete the root!");
if (IsDirectory)
Directory.Delete (FullName, true); // recursive
else
File.Delete (FullName);
parent.children.Remove (name);
parent = null;
}
public FileModel NewFile ()
{
if (! IsDirectory)
throw new ArgumentException ("parent must be a directory");
// no more names left
if (children.Count == Token.Count)
return null;
FileModel child;
child = new FileModel ();
child.name = PickName (this);
child.body = NewBody (10);
child.parent = this;
children [child.name] = child;
// Create the file
child.Write ();
return child;
}
// Creates a randomly-named new directory.
// Avoid name collisions with existing files.
public FileModel NewDirectory ()
{
if (! IsDirectory)
throw new ArgumentException ("parent must be a directory");
// no more names left
if (children.Count == Token.Count)
return null;
FileModel child;
child = new FileModel ();
child.name = PickName (this);
child.children = new Hashtable ();
child.parent = this;
children [child.name] = child;
// Actually create the directory
Directory.CreateDirectory (child.FullName);
child.mtime = Directory.GetLastWriteTimeUtc (child.FullName);
return child;
}
public static FileModel NewRoot ()
{
FileModel root = new FileModel ();
root.name = PathFinder.HomeDir;
root.children = new Hashtable ();
root.mtime = Directory.GetLastWriteTimeUtc (root.FullName);
return root;
}
// IsBelow is easier to thik about than IsDescendantOf
public bool IsBelow (FileModel other)
{
return other.IsAbove (this);
}
// IsAbove is easier to think about than IsAncestorOf
public bool IsAbove (FileModel other)
{
return this == other.parent
|| (other.parent != null && IsAbove (other.parent));
}
// IsBelow is easier to thik about than IsDescendantOf
public bool IsBelow(FileModel other)
{
return(other.IsAbove(this));
}
// IsAbove is easier to think about than IsAncestorOf
public bool IsAbove(FileModel other)
{
return(this == other.parent ||
(other.parent != null && IsAbove(other.parent)));
}
