#include "render/VertexCache.h"
#include "render/loader/GLLoader.h"

namespace td {
namespace render {

void VertexCache::AddData(std::uint64_t index, std::vector<float> positions, std::vector<float> colors) {
    m_Indexes.insert({ index, {positions, colors} });
    m_VertexCount += colors.size(); // one color per vertex
}

void VertexCache::RemoveData(std::uint64_t index) {
    auto it = m_Indexes.find(index);
    if (it != m_Indexes.end()) {
        m_Indexes.erase(it);
        m_VertexCount -= it->second.color.size(); // one color per vertex
    }
}

void VertexCache::Clear() {
    m_Indexes.clear();
    m_VertexCount = 0;
}

void VertexCache::UpdateVertexArray() {
    m_VertexArray = std::make_unique<GL::VertexArray>(m_VertexCount); // one color per vertex

    Vector positions;
    positions.reserve(m_VertexCount * 2);

    Vector colors;
    colors.reserve(m_VertexCount);

    for (auto it = m_Indexes.begin(); it != m_Indexes.end(); it++) {
        const DataIndex& data = it->second;

        positions.insert(positions.end(), data.position.begin(), data.position.end());
        colors.insert(colors.end(), data.color.begin(), data.color.end());
    }

    GL::VertexBuffer positionsBuffer(positions, 2);
    positionsBuffer.AddVertexAttribPointer(0, 2, 0);

    GL::VertexBuffer colorsBuffer(colors, 1);
    colorsBuffer.AddVertexAttribPointer(1, 1, 0);

    m_VertexArray->Bind();
    m_VertexArray->BindVertexBuffer(positionsBuffer);
    m_VertexArray->BindVertexBuffer(colorsBuffer);
    m_VertexArray->Unbind();
}

} // namespace render
} // namespace td