#include "base/CCDirector.h"
#include "2d/CCVertexAttribBind.h"
#include "2d/ccGLStateCache.h"
#include "base/ccMacros.h"
#include "2d/platform/CCFileUtils.h"
#include "2d/uthash.h"
#include "deprecated/CCString.h"

NS_CC_BEGIN

VertexAttribType::VertexAttribType(): _type(GL_FLOAT), _size(0), _location(-1), _offset(0)
{
}
VertexAttribType::VertexAttribType(GLenum type, int size): _type(type), _size(size), _location(-1), _offset(0)
{
    switch (type) {
        case GL_FLOAT_VEC2:
            _type = GL_FLOAT;
            _size = 2;
            break;
        case GL_FLOAT_VEC3:
            _type = GL_FLOAT;
            _size = 3;
            break;
        case GL_FLOAT_VEC4:
            _type = GL_FLOAT;
            _size = 4;
            break;
            
        default:
            break;
    }
}


int VertexAttribType::getByteSize()
{
    int byteSize = 0;
    switch (_type) {
        case GL_BYTE:
        case GL_UNSIGNED_BYTE:
            byteSize = _size;
            break;
        case GL_SHORT:
        case GL_UNSIGNED_SHORT:
            byteSize = _size * sizeof(GLshort);
            break;
        case GL_FLOAT:
            byteSize = _size * sizeof(GLfloat);
            break;
        default:
            CCASSERT(0,"type error");
            break;
    }
    return byteSize;
}

VertexAttribBind::VertexAttribBind(const VertexAttribType* elem, int count)
{
    setVertexAttribElems(elem, count);
}

VertexAttribBind::VertexAttribBind(const std::vector<VertexAttribType>& elems)
{
    setVertexAttribElems(&elems[0], elems.size());
}

VertexAttribBind::VertexAttribBind(const std::vector<GLProgramData::VertexAttib*>& attribs)
{
    std::vector<VertexAttribType> elems;
    for (auto it = attribs.begin(); it != attribs.end(); it++) {
        VertexAttribType type((*it)->_type, (*it)->_size);
        type._location = (*it)->_index;
        elems.push_back(type);
    }
    setVertexAttribElems(&elems[0], elems.size());
}

VertexAttribBind::~VertexAttribBind()
{
    delete[] _vertexAttribs;
}

void VertexAttribBind::bindAttribute(int index, int attribLocation)
{
    //make sure index and attribute location are validate
    _vertexAttribs[index]._location = attribLocation;
}

//bind attributes pointer
void VertexAttribBind::bindAttributePtr(void* vertexPointer)
{
    for (auto i = 0; i < _vertexAtttribCount; i++) {
        auto elem = _vertexAttribs[i];
        if (elem._location != -1)
        {
            glEnableVertexAttribArray(elem._location);
            void* pointer = vertexPointer ? (void*)(((unsigned char*)vertexPointer) + elem._offset) : (void*)elem._offset;
            glVertexAttribPointer(elem._location, elem._size, elem._type, GL_FALSE, _stride, pointer);
        }
    }
}

void VertexAttribBind::setVertexAttribElems(const VertexAttribType* elem, int count)
{
    _vertexAtttribCount = count;
    _vertexAttribs = new VertexAttribType[count];
    _stride = 0;
    for (auto i = 0; i < count; i++) {
        _vertexAttribs[i] = elem[i];
        _vertexAttribs[i]._offset = _stride;
        _stride += _vertexAttribs[i].getByteSize();
    }
}

NS_CC_END