#include "Brushstroke.h"

Brushstroke::~Brushstroke()
{
    delete strokeContext->RenderQueued(&boundingBox); // delete associated texture
    delete strokeContext;
    delete previousTarget;
}

Brushstroke::Brushstroke(StrokeRenderingContext* strokeContext, PaintLayerNode* target, bool isEraser, Brush* brushCopy)
{
    this->strokeContext = strokeContext;
    this->target = target;
    this->isEraser = isEraser;
    this->brushCopy = brushCopy; // this is probably gonna go horribly wrong once users can reload brushes and remove WHICH THEY KINDOF actualy no they can't yet BUT TODO: watch out for this
}

void Brushstroke::Execute()
{
    strokeContext->RenderQueued(&boundingBox);
    assert(boundingBox.w > 0.0f);
    SDL_GPUTextureCreateInfo createInfo = {};
    createInfo.width = (int)boundingBox.w;
    createInfo.height = (int)boundingBox.h;
    createInfo.format = SDL_GPU_TEXTUREFORMAT_R8G8B8A8_UNORM;
    createInfo.usage = SDL_GPU_TEXTUREUSAGE_COLOR_TARGET | SDL_GPU_TEXTUREUSAGE_SAMPLER;
    createInfo.layer_count_or_depth = 1;
    createInfo.num_levels = 1;
    createInfo.sample_count = SDL_GPU_SAMPLECOUNT_1;
    previousTarget = new Texture(createInfo);
    // copy from canvas the current state before we apply
    target->Target->CopyTo(previousTarget, { (int)boundingBox.x, (int)boundingBox.y }, { 0, 0 }, { (int)boundingBox.w, (int)boundingBox.h });
    // apply
    strokeContext->RenderResultOnto(target->Target, isEraser);
    strokeContext->Minimize();
    timestamp = std::chrono::system_clock::now();
}

json Brushstroke::SerializeArgs()
{
    json j = json::object(); // TODO: this command is stateless, meaning things like color, opacity, brush picking needs separate commands, otherwise we have nothing to reconstruct brushstroke fully
    json arr = json::array();
    std::list<PointerEvent> inputs = strokeContext->GetCompleteInputs();
    for (const PointerEvent& input : inputs) {
        json event = json::array();
        event.push_back(input.timestampNanos);
        event.push_back(input.canvasX);
        event.push_back(input.canvasY);
        event.push_back(input.pressure);
        arr.push_back(event);
    }
    j["inputs"] = arr;
    return j;
}

std::string Brushstroke::GetTitle()
{
    return "Brushstroke";
}

void Brushstroke::Undo()
{
    previousTarget->CopyTo(target->Target, { 0, 0 }, { (int)boundingBox.x, (int)boundingBox.y }, { (int)boundingBox.w, (int)boundingBox.h });
}

const char* Brushstroke::GetIdentity() const
{
    return "brushstroke";
}