include/unihashtree.h

/* -*- Mode: C++ -*-
 * Worldvisions Weaver Software:
 *   Copyright (C) 1997-2002 Net Integration Technologies, Inc.
 * 
 * UniConf low-level tree storage abstraction.
 */
#ifndef __UNIHASHTREE_H
#define __UNIHASHTREE_H
 
#include "uniconfkey.h"
#include "wvtr1.h"
#include "wvscatterhash.h"
 
class UniHashTreeBase;
 
// parameters: a node (won't be NULL), userdata
typedef wv::function<void(const UniHashTreeBase*,
                          void*)> UniHashTreeBaseVisitor;
// parameters: 1st node (may be NULL), 2nd node (may be NULL), userdata
typedef wv::function<bool(const UniHashTreeBase*, 
                          const UniHashTreeBase*)> UniHashTreeBaseComparator;
 
class UniHashTreeBase
{
protected:
    struct Accessor
    {
        static const UniConfKey *get_key(const UniHashTreeBase *obj)
            { return &obj->key(); }
    };
 
    typedef WvScatterHash<UniHashTreeBase, UniConfKey, Accessor> Container;
    typedef UniHashTreeBaseVisitor BaseVisitor;
    typedef UniHashTreeBaseComparator BaseComparator;
 
public:
    ~UniHashTreeBase();

    const UniConfKey &key() const
        { return xkey; }

    bool haschildren() const;
 
protected:
    UniHashTreeBase(UniHashTreeBase *parent, const UniConfKey &key);
 
    UniConfKey _fullkey(const UniHashTreeBase *ancestor = NULL) const;
    UniHashTreeBase *_find(const UniConfKey &key) const;
    UniHashTreeBase *_findchild(const UniConfKey &key) const;
 
    static bool _recursivecompare(
        const UniHashTreeBase *a, const UniHashTreeBase *b,
        const UniHashTreeBaseComparator &comparator);
 
    static void _recursive_unsorted_visit(
        const UniHashTreeBase *a,
        const UniHashTreeBaseVisitor &visitor, void *userdata,
        bool preorder, bool postorder);
 
    UniHashTreeBase *xparent; 
    Container *xchildren; 
 
private:
    void _setparent(UniHashTreeBase *parent);
    UniHashTreeBase *_root() const;

    void link(UniHashTreeBase *node);

    void unlink(UniHashTreeBase *node);
 
    UniConfKey xkey;   
 
protected:
    class Iter : public Container::Iter
    {
    public:
        Iter(UniHashTreeBase &b) : Container::Iter(*b.xchildren) { }
    };
    friend class Iter;
};
 
#endif //__UNIHASHTREE_H