#pragma once

#include "../Common/Sizes.hpp"
#include "../Math/Vector.hpp"
#include "ChunkDimensions.hpp"
#include "Position.hpp"

namespace MC::World {

struct ChunkIndex {
    ChunkIndex() : x(0), y(0) {}
    ChunkIndex(I32 x, I32 y) : x(x), y(y) {}

    Vector<3> middle() const {
        using namespace ChunkDimensions;
        return {(x + 0.5f) * Width, Height / 2.0f, (y + 0.5f) * Width};
    }

    Position::BlockWorld local_to_world_position(Position::BlockLocal local) const {
        using namespace ChunkDimensions;
        return {x * Width + local.x(), local.y(), y * Width + local.z()};
    }

    static ChunkIndex from_position(Position::BlockWorld pos) {
        I32 chunk_x = std::round(pos.x() / ChunkDimensions::Width);
        I32 chunk_y = std::round(pos.z() / ChunkDimensions::Width);
        return {chunk_x, chunk_y};
    }

    I32 x, y;
};

}

template<> struct std::equal_to<MC::World::ChunkIndex> {
    Bool operator()(const MC::World::ChunkIndex& i1, const MC::World::ChunkIndex& i2) const noexcept {
        return i1.x == i2.x && i1.y == i2.y;
    }
};

template<> struct std::hash<MC::World::ChunkIndex> {
    USize operator()(const MC::World::ChunkIndex& i) const noexcept {
        return (I64)i.x << 32 | i.y;
    }
};