feat(ECS): Add SparseArrays class for ECS

CMakeLists.txt

@@ -28,6 +28,7 @@ set(HEADERS
     Flakkari/Protocol/Header.hpp
     Flakkari/Protocol/Packet.hpp
     Flakkari/Engine/EntityComponentSystem/Entity.hpp
+    Flakkari/Engine/EntityComponentSystem/SparseArrays.hpp
     Flakkari/Server/UDPServer.hpp
     Flakkari/Server/Client/Client.hpp
     Flakkari/Server/Client/ClientManager.hpp

Flakkari/Engine/EntityComponentSystem/SparseArrays.hpp

@@ -0,0 +1,197 @@
+/**************************************************************************
+ * Flakkari Library v0.1.0
+ *
+ * Flakkari Library is a C++ Library for Network.
+ * @file SparseArrays.hpp
+ * @brief SparseArrays class for ECS (Entity Component System).
+ *
+ * Flakkari Library is under MIT License.
+ * https://opensource.org/licenses/MIT
+ * © 2023 @MasterLaplace
+ * @version 0.1.0
+ * @date 2023-01-05
+ **************************************************************************/
+
+
+#ifndef SPARSEARRAYS_HPP_
+    #define SPARSEARRAYS_HPP_
+
+#include <vector>
+#include <optional>
+#include <type_traits>
+#include <algorithm>
+
+namespace Flakkari::Engine::ECS {
+
+template <typename Component>
+class SparseArrays {
+public:
+    using value_type = std::optional<Component>;
+    using reference_type = value_type&;
+    using const_reference_type = const value_type&;
+    using container_type = std::vector<value_type>;
+    using size_type = typename container_type::size_type;
+    using iterator = typename container_type::iterator;
+    using const_iterator = typename container_type::const_iterator;
+
+public:
+    SparseArrays() = default;
+    SparseArrays(const SparseArrays &other) : _data(other._data) {};
+    SparseArrays(SparseArrays&&other) noexcept : _data(std::move(other._data)) {};
+    ~SparseArrays() = default;
+
+    /**
+     * @brief Copy assignment operator for SparseArrays.
+     *
+     * @param other  The SparseArrays to copy.
+     * @return SparseArrays&  The SparseArrays copied.
+     */
+    SparseArrays &operator=(SparseArrays const &other) {
+        _data = std::move(other._data);
+        return *this;
+    }
+
+    /**
+     * @brief Move assignment operator for SparseArrays.
+     *
+     * @param other  The SparseArrays to move.
+     * @return SparseArrays&  The SparseArrays moved.
+     */
+    SparseArrays &operator=(SparseArrays &&other) noexcept
+    {
+        if (this != &other)
+            std::swap(_data, other._data);
+
+        return *this;
+    }
+
+    /**
+     * @brief Get the component at the index.
+     *
+     * @param idx  The index of the component.
+     * @return reference_type  The component.
+     */
+    reference_type operator[](size_type idx)
+    {
+        if (idx >= _data.size())
+            _data.resize(idx + 1, std::nullopt);
+
+        return _data[idx];
+    }
+
+    /**
+     * @brief Get the component at the index.
+     *        Const version.
+     *
+     * @param idx  The index of the component.
+     * @return const_reference_type  The component.
+     */
+    const_reference_type operator[](size_type idx) const
+    {
+        if (idx >= _data.size())
+            return std::nullopt;
+
+        return _data[idx];
+    }
+
+    iterator begin() { return _data.begin(); }
+
+    const_iterator begin() const { return _data.begin(); }
+
+    const_iterator cbegin() const { return _data.cbegin(); }
+
+    iterator end() { return _data.end(); }
+
+    const_iterator end() const { return _data.end(); }
+
+    const_iterator cend() const { return _data.cend(); }
+
+    size_type size() const { return _data.size(); }
+
+    /**
+     * @brief Insert a component at the end of the SparseArrays.
+     *
+     * @param pos  The position of the component.
+     * @param component  The component to insert.
+     * @return reference_type  The component inserted.
+     */
+    reference_type insert_at(size_type pos, const Component &component)
+    {
+        if (pos >= _data.size())
+            _data.resize(pos + 1, std::nullopt);
+
+        _data[pos].emplace(component);
+        return _data[pos];
+    }
+
+    /**
+     * @brief Insert a component at the end of the SparseArrays.
+     *        Move version.
+     *
+     * @param pos  The position of the component.
+     * @param component  The component to insert.
+     * @return reference_type  The component inserted.
+     */
+    reference_type insert_at(size_type pos, Component &&component)
+    {
+        if (pos >= _data.size())
+            _data.resize(pos + 1, std::nullopt);
+
+        _data[pos] = std::move(component);
+        return _data[pos];
+    }
+
+    /**
+     * @brief Emplace a component at the end of the SparseArrays.
+     *
+     * @tparam Params  The parameters to construct the component.
+     * @param pos  The position of the component.
+     * @param params  The parameters to construct the component.
+     * @return reference_type  The component inserted.
+     */
+    template <class... Params>
+    reference_type emplace_at(size_type pos, Params&&... params)
+    {
+        if (pos >= _data.size())
+            _data.resize(pos + 1, std::nullopt);
+
+        _data[pos].emplace(std::forward<Params>(params)...);
+        return _data[pos];
+    }
+
+    /**
+     * @brief  Erase a component at the position.
+     *
+     * @param pos  The position of the component to erase.
+     */
+    void erase(size_type pos)
+    {
+        if (pos < _data.size())
+            _data[pos].reset();
+    }
+
+    /**
+     * @brief Get the index object from a component.
+     *
+     * @param component  The component to get the index from.
+     * @return size_type  The index of the component.
+     */
+    size_type get_index(value_type const &component) const
+    {
+        auto it = std::find_if(_data.begin(), _data.end(), [&component](auto const& opt) {
+            return opt.has_value() && opt.value() == component;
+        });
+
+        if (it == _data.end())
+            return _data.size();
+
+        return std::distance(_data.begin(), it);
+    }
+
+private:
+    container_type _data;
+};
+
+} // namespace Flakkari::Engine::ECS
+
+#endif /* !SPARSEARRAYS_HPP_ */