/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2007 Robert Osfield
 *
 * This library is open source and may be redistributed and/or modified under
 * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
 * (at your option) any later version.  The full license is in LICENSE file
 * included with this distribution, and on the openscenegraph.org website.
 *
 * This library 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
 * OpenSceneGraph Public License for more details.
*/

#ifndef OSG_STATS
#define OSG_STATS 1

#include <osg/Referenced>
#include <OpenThreads/Mutex>
#include <OpenThreads/ScopedLock>

#include <string>
#include <map>
#include <vector>
#include <ostream>

namespace osg {

class OSG_EXPORT Stats : public osg::Referenced
{
    public:

        Stats(const std::string& name);

        Stats(const std::string& name, unsigned int numberOfFrames);

        void setName(const std::string& name) { _name = name; }
        const std::string& getName() const { return _name; }

        void allocate(unsigned int numberOfFrames);

        unsigned int getEarliestFrameNumber() const { return _latestFrameNumber < static_cast<unsigned int>(_attributeMapList.size()) ? 0 : _latestFrameNumber - static_cast<unsigned int>(_attributeMapList.size()) + 1; }
        unsigned int getLatestFrameNumber() const { return _latestFrameNumber; }

        typedef std::map<std::string, double> AttributeMap;
        typedef std::vector<AttributeMap> AttributeMapList;

        bool setAttribute(unsigned int frameNumber, const std::string& attributeName, double value);

        inline bool getAttribute(unsigned int frameNumber, const std::string& attributeName, double& value) const
        {
            OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_mutex);
            return getAttributeNoMutex(frameNumber, attributeName, value);
        }

        bool getAveragedAttribute(const std::string& attributeName, double& value, bool averageInInverseSpace=false) const;

        bool getAveragedAttribute(unsigned int startFrameNumber, unsigned int endFrameNumber, const std::string& attributeName, double& value, bool averageInInverseSpace=false) const;

        inline AttributeMap& getAttributeMap(unsigned int frameNumber)
        {
            OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_mutex);
            return getAttributeMapNoMutex(frameNumber);
        }

        inline const AttributeMap& getAttributeMap(unsigned int frameNumber) const
        {
            OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_mutex);
            return getAttributeMapNoMutex(frameNumber);
        }

        typedef std::map<std::string, bool> CollectMap;

        void collectStats(const std::string& str, bool flag) { _collectMap[str] = flag; }

        inline bool collectStats(const std::string& str) const
        {
            OpenThreads::ScopedLock<OpenThreads::Mutex> lock(_mutex);

            CollectMap::const_iterator itr = _collectMap.find(str);
            return (itr !=  _collectMap.end()) ? itr->second : false;
        }

        void report(std::ostream& out, const char* indent=0) const;
        void report(std::ostream& out, unsigned int frameNumber, const char* indent=0) const;

    protected:

        virtual ~Stats() {}

        bool getAttributeNoMutex(unsigned int frameNumber, const std::string& attributeName, double& value) const;

        AttributeMap& getAttributeMapNoMutex(unsigned int frameNumber);
        const AttributeMap& getAttributeMapNoMutex(unsigned int frameNumber) const;


        int getIndex(unsigned int frameNumber) const
        {
            // reject frame that are in the future
            if (frameNumber > _latestFrameNumber) return -1;

            // reject frames that are too early
            if (frameNumber < getEarliestFrameNumber()) return -1;

            if (frameNumber >= _baseFrameNumber) return frameNumber - _baseFrameNumber;
            else return static_cast<int>(_attributeMapList.size()) - (_baseFrameNumber-frameNumber);
        }

        std::string         _name;

        mutable OpenThreads::Mutex  _mutex;

        unsigned int        _baseFrameNumber;
        unsigned int        _latestFrameNumber;

        AttributeMapList    _attributeMapList;
        AttributeMap        _invalidAttributeMap;

        CollectMap          _collectMap;

};


}

#endif
