Applied patch by Joseph "looncraz" Groover from ticket #7445.

This changes how Decorators are managed and applied. The app_server
no longer scans and maintains the available ones himself, but is
simply asked to load a Decorator add-on from a provided path.
The Decorator scanning is moved into DecorInfo and DecorInfoUtil,
private classes in the InterfaceKit. The bin command 'setdecor'
uses those.
I cleaned up all the coding style violations that I could find,
removed chunks of code which didn't make sense (if you never put
a NULL pointer into a list, you don't need to check for this and
so on) and also cleaned up other passages for improved clarity
and simplicity.
I also tested the functionality and it works fine. Would even be
Ok to include in Alpha 3, IMHO. Thanks for the patch!


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@41581 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/interface/DecorInfo.h

@@ -0,0 +1,129 @@
+/*
+ * Public domain source code.
+ *
+ * Author:
+ *		Joseph "looncraz" Groover <[email protected]>
+ */
+
+
+#ifndef DECOR_INFO_H
+#define DECOR_INFO_H
+
+
+#include <Entry.h>
+#include <Bitmap.h>
+#include <String.h>
+#include <Locker.h>
+#include <ObjectList.h>
+
+
+// NOTE: DecorInfo itself is not thread-safe
+class DecorInfo {
+public:
+								DecorInfo();
+								DecorInfo(const BString& path);
+								DecorInfo(const entry_ref& ref);
+								~DecorInfo();
+
+			status_t			SetTo(const entry_ref& ref);
+			status_t			SetTo(BString path);
+			status_t			InitCheck()	const;
+			void				Unset();
+
+			bool				IsDefault()	const;
+
+			BString				Path()	const;
+					// Returns "Default" for the default decorator
+
+			const entry_ref*	Ref() const;
+				// Returns NULL if virtual (default) or InitCheck() != B_OK
+				// The ref returned may NOT be the same as the one given to
+				// SetTo or the constructor - we may have traversed a Symlink!
+
+			BString				Name() const;
+			BString				ShortcutName() const;
+
+			BString				Authors() const;
+			BString				ShortDescription() const;
+			BString				LongDescription() const;
+			BString				LicenseURL() const;
+			BString				LicenseName() const;
+			BString				SupportURL() const;
+
+			float				Version() const;
+			time_t				ModificationTime() const;
+
+			bool				CheckForChanges(bool &deleted);
+
+private:
+			void				_Init(bool is_update = false);
+
+private:
+			entry_ref			fRef;
+
+			BString				fPath;
+			BString				fName;
+			BString				fAuthors;
+			BString				fShortDescription;
+			BString				fLongDescription;
+			BString				fLicenseURL;
+			BString				fLicenseName;
+			BString				fSupportURL;
+
+			float				fVersion;
+
+			time_t				fModificationTime;
+
+			status_t			fInitStatus;
+};
+
+
+class DecorInfoUtility{
+public:
+								DecorInfoUtility(bool scanNow = true);
+									// NOTE: When scanNow is passed false,
+									// scanning will be performed lazily, such
+									// as in CountDecorators() and other
+									// methods.
+
+								~DecorInfoUtility();
+
+			status_t			ScanDecorators();
+									// Can also be used to rescan for changes.
+									// Warning: potentially destructive as we
+									// will remove all DecorInfo objects which
+									// no longer have a file system cousin.
+									// TODO: Would a call-back mechanism be
+									// worthwhile here?
+
+			int32				CountDecorators();
+
+			DecorInfo*			DecoratorAt(int32);
+
+			DecorInfo*			FindDecorator(const BString& string);
+									// Checks for ref.name, path, fName, and
+									// "Default," an empty-string returns the
+									// current decorator NULL on match failure
+
+			DecorInfo*			CurrentDecorator();
+			DecorInfo*			DefaultDecorator();
+
+			bool				IsCurrentDecorator(DecorInfo*);
+
+			status_t			SetDecorator(DecorInfo*);
+			status_t			SetDecorator(int32);
+
+			status_t			Preview(DecorInfo* decor, BWindow* window);
+
+private:
+			DecorInfo*			_FindDecor(const BString& path);
+
+private:
+			BObjectList<DecorInfo>	fList;
+			BLocker					fLock;
+			bool					fHasScanned;
+
+};
+
+
+#endif