#include "collectable_sim_ground.hpp"

#include <utility>
#include "../../../../config.h"

void CollectableSimGround::closeAllHoles()
{
    segments.clear();

    // Create one segment for the ground
    auto groundSegment = std::make_shared<CollectableSimGroundSegment>(world);
    groundSegment->body->createSquare(b2_kinematicBody,
                                      {0, -COLLECTABLES_SIM_GROUND_THICKNESS / 2.f},
                                      {groundWidth, COLLECTABLES_SIM_GROUND_THICKNESS});

    segments.push_back(groundSegment);
}

CollectableSimGround::CollectableSimGround(std::shared_ptr<b2World> world, float groundWidth)
        : world(std::move(world))
{
    setGroundWidth(groundWidth);
    closeAllHoles();
}

void CollectableSimGround::setGroundWidth(float width)
{
    if (width <= 0)
    {
        throw std::runtime_error("Ground width must be greater than 0");
    }

    if (width == groundWidth)
    {
        return;
    }

    groundWidth = width;
    updateOuterSegmentsToWidth();
}

void CollectableSimGround::updateOuterSegmentsToWidth()
{
    auto outerSegments = getOuterSegments();
    auto borderPoints = groundWidth / 2.f;

    // Left segment
    if (outerSegments.left != nullptr)
    {
        auto leftSegment = outerSegments.left->body;
        auto leftCenter = leftSegment->getCenter();
        auto leftSize = leftSegment->getSize();
        auto deltaToBorder = borderPoints - abs(leftCenter.x - leftSize.x / 2.f);

        // Increase width if positive, decrease if negative
        leftSize.x += deltaToBorder;
        leftCenter.x -= deltaToBorder / 2.f;

        leftSegment->setBoxSize(leftSize);
        leftSegment->setCenter(leftCenter);
    }

    // Right segment
    if (outerSegments.right != nullptr)
    {
        auto rightSegment = outerSegments.right->body;
        auto rightCenter = rightSegment->getCenter();
        auto rightSize = rightSegment->getSize();
        auto deltaToBorder = borderPoints - abs(rightCenter.x + rightSize.x / 2.f);

        // Increase width if positive, decrease if negative
        rightSize.x += deltaToBorder;
        rightCenter.x += deltaToBorder / 2.f;

        rightSegment->setBoxSize(rightSize);
        rightSegment->setCenter(rightCenter);
    }
}

CollectableSimGround::SideSegments CollectableSimGround::getOuterSegments(int holeId)
{
    SideSegments sideSegments;

    for (const auto &segment: segments)
    {
        // If valid holeId, match left hole id
        // If invalid holeId, get outer segment
        if ((segment->leftHoleId == holeId && holeId >= 0)
            || (segment->rightHoleId < 0 && holeId < 0))
        {
            sideSegments.right = segment;
        }

        if ((segment->rightHoleId == holeId && holeId >= 0)
            || (segment->leftHoleId < 0 && holeId < 0))
        {
            sideSegments.left = segment;
        }
    }

    return sideSegments;
}