path: root/libopie2/opiepim/core/opimaccesstemplate.h

/*
                             This file is part of the Opie Project
                             Copyright (C) Holger Freyther <zecke@handhelds.org>
                 Copyright (C) Stefan Eilers <eilers.stefan@epost.de>
              =.             Copyright (C) The Opie Team <opie-devel@handhelds.org>
            .=l.
           .>+-=
 _;:,     .>    :=|.         This program is free software; you can
.> <`_,   >  .   <=          redistribute it and/or  modify it under
:`=1 )Y*s>-.--   :           the terms of the GNU Library General Public
.="- .-=="i,     .._         License as published by the Free Software
 - .   .-<_>     .<>         Foundation; either version 2 of the License,
     ._= =}       :          or (at your option) any later version.
    .%`+i>       _;_.
    .i_,=:_.      -<s.       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., 59 Temple Place - Suite 330,
                             Boston, MA 02111-1307, USA.
*/
#ifndef OPIE_PIM_ACCESS_TEMPLATE_H
#define OPIE_PIM_ACCESS_TEMPLATE_H

/* OPIE */
#include <opie2/opimrecord.h>
#include <opie2/opimaccessbackend.h>
#include <opie2/opimrecordlist.h>

#include <opie2/opimtemplatebase.h>
#include <opie2/odebug.h>

/* QT */
#include <qarray.h>

namespace Opie {

class OPimAccessTemplatePrivate;
/**
 * Thats the frontend to our OPIE PIM
 * Library. Either you want to use it's
 * interface or you want to implement
 * your own Access lib
 * Just create a OPimRecord and inherit from
 * the templates
 */

template <class T = OPimRecord >
class OPimAccessTemplate : public OTemplateBase<T> {
public:
    enum Access {
        Random = 0,
        SortedAccess
    };
    typedef OPimRecordList<T> List;
    typedef OPimAccessBackend<T> BackEnd;
    typedef OPimCache<T> Cache;

    /**
     * c'tor BackEnd
     * enum Access a small hint on how to handle the backend
     */
    OPimAccessTemplate( BackEnd* end);

    virtual ~OPimAccessTemplate();

    /**
     * load from the backend
     */
    bool load();

    /** Reload database.
     * You should execute this function if the external database
     * was changed.
     * This function will load the external database and afterwards
     * rejoin the local changes. Therefore the local database will be set consistent.
     */
    virtual bool reload();

    /** Save contacts database.
     * Save is more a "commit". After calling this function, all changes are public available.
     * @return true if successful
     */
    bool save();

    /**
     * if the resource was changed externally
     * You should use the signal handling instead of polling possible changes !
     * zecke: Do you implement a signal for otodoaccess ?
     */
    bool wasChangedExternally()const;

    /**
     * return a List of records
     * you can iterate over them
     */
    virtual List allRecords()const;

     /**
     * return a List of records
     * that match the regex
     */
    virtual List matchRegexp(  const QRegExp &r ) const;

    /**
     * queryByExample.
     * @see otodoaccess, ocontactaccess
     */
    virtual List queryByExample( const T& t, int querySettings, const QDateTime& d = QDateTime() );

    /**
     * find the OPimRecord uid
     */
    T find( int uid )const;

    /**
     * read ahead cache find method ;)
     */
    T find( int uid, const QArray<int>&,
                    uint current, typename OTemplateBase<T>::CacheDirection dir = OTemplateBase<T>::Forward )const;


    /* invalidate cache here */
    /**
     * clears the backend and invalidates the backend
     */
    void clear() ;

    /**
     * add T to the backend
     * @param t The item to add.
     * @return <i>true</i> if added successfully.
     */
     virtual bool add( const T& t ) ;

    bool add( const OPimRecord& );
    /** 
     * Add an Opie PimRecord.
     * Info: Take this if  you are working with OPimRecords and you need to add it into any database.
     *       But take care that the accessing database is compatible to the real type of OPimRecord !! 
     *       Otherwise this access will be rejected !
     */
    bool add( const OPimRecord* );


    /* only the uid matters */
    /**
     * remove T from the backend
     * @param t The item to remove
     * @return <i>true</i> if successful.
     */
    virtual bool remove( const T& t );

    /**
     * remove the OPimRecord with uid
     * @param uid The ID of the item to remove
     * @return <i>true</i> if successful.
     */
    bool remove( int uid );
    bool remove( const OPimRecord& );

    /**
     * replace T from backend
     * @param t The item to replace
     * @return <i>true</i> if successful.
     */
    virtual bool replace( const T& t) ;

    void setReadAhead( uint count );
    /**
     * @internal
     */
    virtual T cacheFind( int uid )const;
    void cache( const T& )const;
    void setSaneCacheSize( int );

    QArray<int> records()const;
protected:
    /**
     * invalidate the cache
     */
    void invalidateCache();

    void setBackEnd( BackEnd* end );
    /**
     * returns the backend
     */
    BackEnd* backEnd();
    BackEnd* m_backEnd;

    Cache m_cache;

private:
    OPimAccessTemplatePrivate *d;

};

template <class T>
OPimAccessTemplate<T>::OPimAccessTemplate( BackEnd* end )
    : OTemplateBase<T>(), m_backEnd( end )
{
    if (end )
        end->setFrontend( this );
}
template <class T>
OPimAccessTemplate<T>::~OPimAccessTemplate() {
    owarn << "~OPimAccessTemplate<T>" << oendl;
    delete m_backEnd;
}
template <class T>
bool OPimAccessTemplate<T>::load() {
    invalidateCache();
    return m_backEnd->load();
}
template <class T>
bool OPimAccessTemplate<T>::reload() {
    invalidateCache();
    return m_backEnd->reload();
}
template <class T>
bool OPimAccessTemplate<T>::save() {
    return m_backEnd->save();
}
template <class T>
typename OPimAccessTemplate<T>::List OPimAccessTemplate<T>::allRecords()const {
    QArray<int> ints = m_backEnd->allRecords();
    List lis(ints, this );
    return lis;
}
template <class T>
typename OPimAccessTemplate<T>::List OPimAccessTemplate<T>::matchRegexp( const QRegExp &r )const {
    QArray<int> ints = m_backEnd->matchRegexp( r );
    List lis(ints, this );
    return lis;
}
template <class T>
QArray<int> OPimAccessTemplate<T>::records()const {
    return m_backEnd->allRecords();
}
template <class T>
typename OPimAccessTemplate<T>::List
OPimAccessTemplate<T>::queryByExample( const T& t, int settings, const QDateTime& d ) {
    QArray<int> ints = m_backEnd->queryByExample( t, settings, d );

    List lis(ints, this );
    return lis;
}
template <class T>
T OPimAccessTemplate<T>::find( int uid ) const{
    // First search in cache..
    if ( m_cache.contains( uid ) )
	    return m_cache.find( uid );

    T t = m_backEnd->find( uid );
    cache( t );

    return t;
}

template <class T>
T OPimAccessTemplate<T>::cacheFind( int uid ) const
{
	return m_cache.find( uid );
}

template <class T>
T OPimAccessTemplate<T>::find( int uid, const QArray<int>& ar,
                               uint current, typename OTemplateBase<T>::CacheDirection dir )const {
    /*
     * better do T.isEmpty()
     * after a find this way we would
     * avoid two finds in QCache...
     */
    // owarn << "find it now " << uid << oendl;
    if ( m_cache.contains( uid ) ) {
        return m_cache.find( uid );
    }

    T t = m_backEnd->find( uid, ar, current, dir );
    cache( t );
    return t;
}
template <class T>
void OPimAccessTemplate<T>::clear() {
    invalidateCache();
    m_backEnd->clear();
}
template <class T>
bool OPimAccessTemplate<T>::add( const T& t ) {
    cache( t );
    return m_backEnd->add( t );
}

template <class T>
bool OPimAccessTemplate<T>::add( const OPimRecord& rec ) {
    /* same type */
    T tempInstance;
    if ( rec.rtti() == tempInstance.rtti() ) {
        const T& t = static_cast<const T&>(rec);
        return add(t);
    } else {
	owarn << "Adding not possible: Objecttype mismatch" << oendl;
    }
    return false;
}

template <class T>
bool OPimAccessTemplate<T>::add( const OPimRecord* rec) {
    /* same type, but pointer  */
    T tempInstance;
    if ( rec -> rtti() == tempInstance.rtti() ) {
        const T* t = static_cast<const T*>(rec);
        return add( *t );
    } else {
	owarn << "Adding not possible: Objecttype mismatch" << oendl;
    }
    return false;
}

template <class T>
bool OPimAccessTemplate<T>::remove( const T& t ) {
    return remove( t.uid() );
}
template <class T>
bool OPimAccessTemplate<T>::remove( int uid ) {
    m_cache.remove( uid );
    return m_backEnd->remove( uid );
}
template <class T>
bool OPimAccessTemplate<T>::remove( const OPimRecord& rec) {
    return remove( rec.uid() );
}
template <class T>
bool OPimAccessTemplate<T>::replace( const T& t ) {
    m_cache.replace( t );
    return m_backEnd->replace( t );
}
template <class T>
void OPimAccessTemplate<T>::invalidateCache() {
    m_cache.invalidate();
}
template <class T>
typename OPimAccessTemplate<T>::BackEnd* OPimAccessTemplate<T>::backEnd() {
    return m_backEnd;
}
template <class T>
bool OPimAccessTemplate<T>::wasChangedExternally()const {
    return false;
}
template <class T>
void OPimAccessTemplate<T>::setBackEnd( BackEnd* end ) {
    m_backEnd = end;
    if (m_backEnd )
        m_backEnd->setFrontend( this );
}
template <class T>
void OPimAccessTemplate<T>::cache( const T& t ) const{
    /* hacky we need to work around the const*/
    ((OPimAccessTemplate<T>*)this)->m_cache.add( t );
}
template <class T>
void OPimAccessTemplate<T>::setSaneCacheSize( int size ) {
    m_cache.setSize( size );
}
template <class T>
void OPimAccessTemplate<T>::setReadAhead( uint count ) {
    m_backEnd->setReadAhead( count );
}

}

#endif