bool IAddChildViewModel.CanAddChildren(IReadOnlyCollection <object> children, AddChildModifiers modifiers, out string message)
{
if (children.Any(x => (x is IIsEditableViewModel) && !((IIsEditableViewModel)x).IsEditable))
{
message = "Some source items are read-only";
return(false);
}
if (!Package.IsEditable)
{
message = "Read-only package";
return(false);
}
message = $"Add to {Path}";
foreach (var child in children)
{
var mountPoint = child as MountPointViewModel;
var directory = child as DirectoryViewModel;
var asset = child as AssetViewModel;
if (mountPoint != null)
{
message = DragDropBehavior.InvalidDropAreaMessage;
return(false);
}
if (directory != null)
{
if (directory == this)
{
message = "Can't drop a folder on itself or its children";
return(false);
}
if (directory.Root.GetType() != Root.GetType())
{
message = "Incompatible folder";
return(false);
}
if (directory.Root is ProjectViewModel && Root != directory.Root)
{
message = "Can't move source files between projects";
return(false);
}
if (SubDirectories.Any(x => x.Name == directory.Name))
{
message = $"Directory {((this is DirectoryViewModel) ? Path : Name)} already contains a subfolder named {directory.Name}";
return(false);
}
if (children.OfType <DirectoryViewModel>().Any(x => x != child && string.Compare(x.Name, directory.Name, StringComparison.OrdinalIgnoreCase) == 0))
{
message = "Can't move directories with duplicate names";
return(false);
}
var currentParent = Parent;
while (currentParent != null)
{
if (currentParent == directory)
{
message = "Can't drop a directory on itself or its children";
return(false);
}
currentParent = currentParent.Parent;
}
}
else if (asset != null)
{
if (asset.IsLocked)
{
message = $"Asset {asset.Url} can't be moved";
return(false);
}
if (Assets.Any(x => string.Compare(x.Name, asset.Name, StringComparison.OrdinalIgnoreCase) == 0))
{
message = $"{(!string.IsNullOrEmpty(Path) ? $"Directory {Path}" : "This directory")} already contains an asset named {asset.Name}";
return(false);
}
if (children.OfType <AssetViewModel>().Any(x => x != child && string.Compare(x.Name, asset.Name, StringComparison.OrdinalIgnoreCase) == 0))
{
message = "Can't move assets with duplicate names";
return(false);
}
if (asset.Directory.Root.GetType() != Root.GetType())
{
message = "Incompatible folder";
return(false);
}
if (asset.Directory.Root is ProjectViewModel && Root != asset.Directory.Root)
{
message = "Can't move source files between projects";
return(false);
}
}
else
{
message = "Only folders can be dropped";
return(false);
}
}
return(true);
}