tdeaccelgen.h

/*  This file is part of the KDE project
    Copyright (C) 2000 Keunwoo Lee <klee@cs.washington.edu>
 
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Library General Public License for more details.
 
    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB. If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA  02110-1301, USA.
*/
 
#ifndef TDEACCELGEN_H
#define TDEACCELGEN_H
 
#include <tqmap.h>
#include <tqstring.h>
#include <tqstringlist.h>
 
#include <tdelibs_export.h>
 
namespace TDEAccelGen
{
 
// HELPERS
 
template <class Iter>
class Deref
{
public:
    static TQString deref(Iter i) { return *i; }
};
 
template <class Iter>
class Deref_Key
{
public:
    static TQString deref(Iter i) { return i.key(); }
};
 
inline bool
isLegalAccelerator(const TQString& str, uint index)
{
    return index < str.length()
        && str[index].isLetterOrNumber();
}
 
template <class Iter, class Deref>
inline void
loadPredefined(Iter begin, Iter end, TQMap<TQChar,bool>& keys)
{
    for (Iter i = begin; i != end; ++i) {
        TQString item = Deref::deref(i);
        int user_ampersand = item.find(TQChar('&'));
        if( user_ampersand >= 0 ) {
            // Sanity check.  Note that we don't try to find an
            // accelerator if the user shoots him/herself in the foot
            // by adding a bad '&'.
            if( isLegalAccelerator(item, user_ampersand+1) ) {
                keys.insert(item[user_ampersand+1], true);
            }
        }
    }
}
 
 
// ///////////////////////////////////////////////////////////////////
// MAIN USER FUNCTIONS
 
 
template <class Iter, class Iter_Deref >
void
generate(Iter begin, Iter end, TQStringList& target)
{
    // Will keep track of used accelerator chars
    TQMap<TQChar,bool> used_accels;
 
    // Prepass to detect manually user-coded accelerators
    loadPredefined<Iter,Iter_Deref>(begin, end, used_accels);
 
    // Main pass
    for (Iter i = begin; i != end; ++i) {
        TQString item = Iter_Deref::deref(i);
 
        // Attempt to find a good accelerator, but only if the user
        // has not manually hardcoded one.
        int user_ampersand = item.find(TQChar('&'));
        if( user_ampersand < 0 || item[user_ampersand+1] == '&') {
            bool found = false;
            uint found_idx;
            uint j;
 
            // Check word-starting letters first.
            for( j=0; j < item.length(); ++j ) {
                if( isLegalAccelerator(item, j)
                    && !used_accels.contains(item[j])
                    && (0 == j || (j > 0 && item[j-1].isSpace())) ) {
                    found = true;
                    found_idx = j;
                    break;
                }
            }
 
            if( !found ) {
                // No word-starting letter; search for any letter.
                for( j=0; j < item.length(); ++j ) {
                    if( isLegalAccelerator(item, j)
                        && !used_accels.contains(item[j]) ) {
                        found = true;
                        found_idx = j;
                        break;
                    }
                }
            }
 
            if( found ) {
                // Both upper and lower case marked as used
                used_accels.insert(item[j].upper(),true);
                used_accels.insert(item[j].lower(),true);
                item.insert(j,TQChar('&'));
            }
        }
 
        target.append( item );
    }
}
 
template <class Iter>
inline void
generateFromKeys(Iter begin, Iter end, TQStringList& target)
{
    generate< Iter, Deref_Key<Iter> >(begin, end, target);
}
 
 
inline void
generate(const TQStringList& source, TQStringList& target)
{
    generate<TQStringList::ConstIterator, Deref<TQStringList::ConstIterator> >(source.begin(), source.end(), target);
}
 
template <class Key>
inline void
generateFromValues(const TQMap<Key,TQString>& source, TQStringList& target)
{
    generate<TQMapConstIterator<Key,TQString>, Deref_Key<TQMapConstIterator<Key,TQString> > >(source.begin(), source.end(), target);
}
 
template <class Data>
inline void
generateFromKeys(const TQMap<TQString,Data>& source, TQStringList& target)
{
    generateFromKeys(source.begin(), source.end(), target);
}
 
 
} // end namespace TDEAccelGen
 
#endif