/* This file is part of the Pangolin Project.
 * http://github.com/stevenlovegrove/Pangolin
 *
 * Copyright (c) 2011 Steven Lovegrove
 *
 * 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.
 */

#pragma once

#include <map>

#include <pangolin/scene/interactive.h>

namespace pangolin {

class InteractiveIndex
{
public:
    class Token
    {
    public:
        friend class InteractiveIndex;

        Token()
            : id(0)
        {
        }

        Token(Token&& o)
            : id(o.id)
        {
            o.id = 0;
        }

        GLint Id() const
        {
            return id;
        }

        ~Token()
        {
            if(id) {
                InteractiveIndex::I().Unstore(*this);
            }
        }

    private:
        Token(GLint id)
            : id(id)
        {
        }


        GLint id;
    };

    static InteractiveIndex& I()
    {
        static InteractiveIndex instance;
        return instance;
    }

    Interactive* Find(GLuint id)
    {
        auto kv = index.find(id);
        if(kv != index.end()) {
            return kv->second;
        }
        return nullptr;
    }

    Token Store(Interactive* r)
    {
        index[next_id] = r;
        return Token(next_id++);
    }

    void Unstore(Token& t)
    {
        index.erase(t.id);
        t.id = 0;
    }

private:
    // Private constructor.
    InteractiveIndex()
        : next_id(1)
    {
    }

    GLint next_id;
    std::map<GLint, Interactive*> index;
};

}
