#include "ui.hpp"

#include "text.hpp"

#include <SDL2/SDL_opengl.h>
#include <iostream>
#include <string>

static const unsigned int NRE_TEX_DATA = 0xBBBBBBBB;

void UISystem::configure(entityx::EntityManager&, entityx::EventManager&)
{
}

void UISystem::createDialogBox(float x, float y, float w, float h)
{
    // Queue for generation in the main thread.
    m_boxes.emplace_back(0, x, -y, w, h);
}

void UISystem::update(entityx::EntityManager&,
    entityx::EventManager& events,
    entityx::TimeDelta)
{
    for (auto& b : m_boxes) {
        if (b.vbo == 0) {
            auto nre = generateDialogBox(b);
            events.emit<NewRenderEvent>(nre);
        }
    }
}

NewRenderEvent UISystem::generateDialogBox(Box& box)
{
    NewRenderEvent nre;
    std::basic_string<TextMeshData> buffer;

    glGenBuffers(1, &nre.vbo);
    glGenTextures(1, &nre.tex);
    box.vbo = nre.vbo;

    glBindTexture(GL_TEXTURE_2D, nre.tex);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 1, 1, 0, GL_RGBA,
                 GL_UNSIGNED_BYTE, &NRE_TEX_DATA);

    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    buffer += { box.x, box.y, -5, 0, 0, 1 };
    buffer += { box.x + box.w, box.y, -5, 0, 0, 1 };
    buffer += { box.x + box.w, box.y + box.h, -5, 0, 0, 1 };
    buffer += { box.x + box.w, box.y + box.h, -5, 0, 0, 1 };
    buffer += { box.x, box.y + box.h, -5, 0, 0, 1 };
    buffer += { box.x, box.y, -5, 0, 0, 1 };

    glBindBuffer(GL_ARRAY_BUFFER, nre.vbo);
    glBufferData(GL_ARRAY_BUFFER,
                 buffer.size() * sizeof(TextMeshData), buffer.data(),
                 GL_DYNAMIC_DRAW);

    nre.normal = 0;
    nre.vertex = buffer.size();
    return nre;
}