/****************************************************************************
Copyright (c) 2011      Ricardo Quesada
Copyright (c) 2010-2012 cocos2d-x.org
Copyright (c) 2011      Zynga Inc.
Copyright (c) 2013-2017 Chukong Technologies Inc.

http://www.cocos2d-x.org

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 __CCGLPROGRAMCACHE_H__
#define __CCGLPROGRAMCACHE_H__

#include <string>
#include <unordered_map>

#include "base/CCRef.h"

/**
 * @addtogroup renderer
 * @{
 */

NS_CC_BEGIN

class GLProgram;

/** GLProgramCache
 Singleton that stores manages GLProgram objects (shaders)
 @since v2.0
 */
class CC_DLL GLProgramCache : public Ref
{
public:
    /**
    Constructor.
     * @js ctor
     */
    GLProgramCache();
    /**
    Destructor.
     * @js NA
     * @lua NA
     */
    ~GLProgramCache();

    /** returns the shared instance */
    static GLProgramCache* getInstance();

    /** purges the cache. It releases the retained instance. */
    static void destroyInstance();

    /** @deprecated Use getInstance() instead */
    CC_DEPRECATED_ATTRIBUTE static GLProgramCache* sharedShaderCache();

    /** @deprecated Use destroyInstance() instead */
    CC_DEPRECATED_ATTRIBUTE static void purgeSharedShaderCache();

    /** loads the default shaders */
    void loadDefaultGLPrograms();
    CC_DEPRECATED_ATTRIBUTE void loadDefaultShaders() { loadDefaultGLPrograms(); }

    /** reload the default shaders */
    void reloadDefaultGLPrograms();
    CC_DEPRECATED_ATTRIBUTE void reloadDefaultShaders() { reloadDefaultGLPrograms(); }

    /** returns a GL program for a given key 
     */
    GLProgram * getGLProgram(const std::string &key);
    CC_DEPRECATED_ATTRIBUTE GLProgram * getProgram(const std::string &key) { return getGLProgram(key); }
    CC_DEPRECATED_ATTRIBUTE GLProgram * programForKey(const std::string &key){ return getGLProgram(key); }

    /** adds a GLProgram to the cache for a given name */
    void addGLProgram(GLProgram* program, const std::string &key);
    CC_DEPRECATED_ATTRIBUTE void addProgram(GLProgram* program, const std::string &key) { addGLProgram(program, key); }
    
    /** reload default programs these are relative to light */
    void reloadDefaultGLProgramsRelativeToLights();

private:
    /**
    @{
        Init and load predefined shaders.
    */
    bool init();
    void loadDefaultGLProgram(GLProgram *program, int type);
    /**
    @}
    */

    /**Get macro define for lights in current openGL driver.*/
    std::string getShaderMacrosForLight() const;

    /**Predefined shaders.*/
    std::unordered_map<std::string, GLProgram*> _programs;
};

NS_CC_END
// end of shaders group
/// @}

#endif /* __CCGLPROGRAMCACHE_H__ */