/*****************************************************************************/
// LiveSettings
// Written by Michael Wilber
//
// LiveSettings.h
//
// This class manages (saves/loads/locks/unlocks) a collection of BMessage
// based settings. This class allows you to share settings between different
// classes in different threads and receive notifications when the settings
// change. This class makes it easy to share settings between a Translator
// and its config panel or a Screen Saver and its config panel.
//
//
// Copyright (C) Haiku
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense, 
// and/or sell copies of the Software, and to permit persons to whom the 
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included 
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
/*****************************************************************************/

#ifndef LIVE_SETTINGS_H
#define LIVE_SETTINGS_H

#include <Locker.h>
#include <Path.h>
#include <Message.h>
#include <String.h>
#include <vector>
#include "LiveSettingsObserver.h"
#include "LiveSetting.h"

class LiveSettings {
public:
        LiveSettings(const char *settingsFile, LiveSetting *defaults,
                int32 defCount);
        
        LiveSettings *Acquire();
                // increments the reference count, returns this
        LiveSettings *Release();
                // decrements the reference count, deletes this
                // when count reaches zero, returns this when 
                // ref count is greater than zero, NULL when
                // ref count is zero
                
        bool AddObserver(LiveSettingsObserver *observer);
                // returns true if observer was added sucessfully, 
                // false if observer already in the list or error
        bool RemoveObserver(LiveSettingsObserver *observer);
                // returns true if observer was removed successfully,
                // false if observer not found or error
        
        status_t LoadSettings();
        status_t LoadSettings(BMessage *pmsg);
        status_t SaveSettings();
        status_t GetConfigurationMessage(BMessage *pmsg);
        
        bool SetGetBool(const char *name, bool *pVal = NULL);
        int32 SetGetInt32(const char *name, int32 *pVal = NULL);
        
        void SetString(const char *name, const BString &str);
        void GetString(const char *name, BString &str);
        
private:
        const LiveSetting *FindLiveSetting(const char *name);
        ~LiveSettings();
                // private so that Release() must be used
                // to delete the object
                
        void NotifySettingChanged(uint32 setting);
        
        template <class T>
        bool GetValue(const char *name, T &val);
        
        template <class T>
        bool SetValue(const char *name, const T &val);
        
        BLocker fLock;
        int32 fRefCount;
        BPath fSettingsPath;
                // where the settings file will be loaded from /
                // saved to
        
        BMessage fSettingsMsg;
                // the actual settings
                
        const LiveSetting *fDefaults;
        int32 fDefCount;
        
        typedef std::vector<LiveSettingsObserver *> ObserverList;
        ObserverList fObservers;
};

#endif // #ifndef LIVE_SETTTINGS_H