#include "textureredux.h"
#include "texture.h"
#include "glassert.h"
#include "shader.h"
#include <glm/ext.hpp>

TextureRedux::TextureRedux(FrameBuffer* input, int textureId) :
    m_shader(NULL)
{
    Texture* inputTexture = input->getTexture(textureId);
    Texture* tex = new Texture(inputTexture, true);
    ping.addTexture(tex, GL_COLOR_ATTACHMENT0);
    pong.addTexture(inputTexture, GL_COLOR_ATTACHMENT0);

    ping.initColorAttachments();
    pong.initColorAttachments();
}

TextureRedux::~TextureRedux()
{
    delete(ping.getTexture(0));
}

void TextureRedux::setShader(Shader* shader)
{
    m_shader = shader;
    uniformLocations[SAMPLER] = shader->getLocation("colorSampler");
    uniformLocations[WIDTH] = shader->getLocation("width");
    uniformLocations[HEIGTH] = shader->getLocation("height");
}

glm::vec3 TextureRedux::redux()
{
    bool inverted = false;
    int tempWidth = pong.getTexture(0)->getWidth();
    int tempHeight = pong.getTexture(0)->getHeight();
    while(tempWidth > 1 && tempHeight > 1)
    {
        m_shader->bind();
        m_shader->bindInteger(uniformLocations[SAMPLER], 0);
        m_shader->bindInteger(uniformLocations[WIDTH], tempWidth);
        m_shader->bindInteger(uniformLocations[HEIGTH], tempHeight);
        if(inverted)
        {
            ping.getTexture(0)->bind(0);
            pong.bindFBO();
        }
        else
        {
            ping.bindFBO();
            pong.getTexture(0)->bind(0);
        }
        tempWidth /= 2;
        tempHeight /= 2;
        glViewport(0, 0, tempWidth, tempHeight);
        glAssert(glDrawArrays(GL_TRIANGLES, 0, 3));
    }
    glm::vec3 minMaxMean;
    glAssert(glReadPixels(0, 0, 0, 0, GL_RGB, GL_FLOAT, glm::value_ptr(minMaxMean)));
    return minMaxMean;
}