#include "texture.h"
#include "glassert.h"
#include "image.h"

Texture::Texture(GLenum format,
                 GLenum internal_format,
                 int width,
                 int height,
                 GLenum dataType,
                 GLenum texTarget) :
    target(texTarget)
{
    glAssert(glGenTextures(1, &texId));
    glAssert(glBindTexture(target, texId));
    glAssert(glTexImage2D(target, 0, internal_format, width, height, 0, format, dataType, NULL));
    setWrap(GL_REPEAT);
    setFiltering(GL_LINEAR);
}

Texture::Texture(Image* myImage) : target(GL_TEXTURE_2D)
{
    glAssert(glGenTextures(1, &texId));
    glAssert(glBindTexture(target, texId));
    initPixels(myImage, GL_TEXTURE_2D);
    setWrap(GL_REPEAT);
    setFiltering(GL_LINEAR);
}

Texture::Texture(Image* myCubemapImages[6]) : target(GL_TEXTURE_CUBE_MAP)
{
    glAssert(glActiveTexture(GL_TEXTURE0));
    glAssert(glGenTextures(1, &texId));
    glAssert(glBindTexture(target, texId));

    for(int i=0; i<6; ++i)
    {
        initPixels(myCubemapImages[i], GL_TEXTURE_CUBE_MAP_POSITIVE_X + i);
        setWrap(GL_CLAMP_TO_EDGE);
        setFiltering(GL_LINEAR);
    }
}

Texture::~Texture()
{
    glAssert(glDeleteTextures(1, &texId));
}

void Texture::initPixels(Image* myImage, GLenum target)
{
    switch(myImage->depth)
    {
    case 32:
        glAssert(glTexImage2D(target, 0, GL_RGBA, myImage->width, myImage->height, 0, GL_BGRA, GL_UNSIGNED_BYTE, myImage->pixels));
        break;
    case 24:
        glAssert(glTexImage2D(target, 0, GL_RGB, myImage->width, myImage->height, 0, GL_BGR, GL_UNSIGNED_BYTE, myImage->pixels));
        break;
    case 8:
        glAssert(glTexImage2D(target, 0, GL_R8, myImage->width, myImage->height, 0, GL_RED, GL_UNSIGNED_BYTE, myImage->pixels));
        break;
    }
}

void Texture::setWrap(GLint wrap)
{
    glAssert(glTexParameteri(target, GL_TEXTURE_WRAP_S, wrap));
    glAssert(glTexParameteri(target, GL_TEXTURE_WRAP_T, wrap));
    glAssert(glTexParameteri(target, GL_TEXTURE_WRAP_R, wrap));
}

void Texture::setFiltering(GLint filter)
{
    glAssert(glTexParameteri(target, GL_TEXTURE_MIN_FILTER, filter));
    glAssert(glTexParameteri(target, GL_TEXTURE_MAG_FILTER, filter));
}

void Texture::bind(int slot)
{
    GLenum texSlot = GL_TEXTURE0+slot;
    glAssert(glActiveTexture(texSlot));
    glAssert(glBindTexture(target, texId));
}