- deque, object_pool, and graph data structures + PrettyPrinters

include/fennec/containers/deque.h

@@ -0,0 +1,199 @@
+// =====================================================================================================================
+//  fennec, a free and open source game engine
+//  Copyright © 2025  Medusa Slockbower
+//
+//  This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+// =====================================================================================================================
+
+#ifndef FENNEC_CONTAINERS_DEQUE_H
+#define FENNEC_CONTAINERS_DEQUE_H
+
+#include <fennec/memory/allocator.h>
+
+// TODO: Document
+
+namespace fennec
+{
+
+template<typename TypeT, typename AllocT = allocator<TypeT>>
+struct deque {
+
+// Definitions =========================================================================================================
+public:
+	using elem_t = TypeT;
+
+	struct node {
+		elem_t value;
+		node *prev, *next;
+
+		template<typename...ArgsT>
+		node(node* prev, node* next, ArgsT&&...args)
+			: value(fennec::forward<ArgsT>(args)...)
+			, prev(prev), next(next) {
+		}
+
+		~node() = default;
+	};
+
+	using alloc_t = allocator_traits<AllocT>::template rebind<node>;
+
+
+// Constructors ========================================================================================================
+
+	deque()
+		: _alloc()
+		, _first(nullptr)
+		, _last(nullptr) {
+	}
+
+	deque(deque&& deque) noexcept
+		: _alloc(deque._alloc)
+		, _first(deque._first)
+		, _last(deque._last) {
+		deque._first = nullptr;
+		deque._last  = nullptr;
+	}
+
+	~deque() {
+		clear();
+	}
+
+// Properties ==========================================================================================================
+
+	bool empty() const {
+		return _size == 0;
+	}
+
+	size_t size() const {
+		return _size;
+	}
+
+
+// Access ==============================================================================================================
+
+	elem_t& front() {
+		assert(not empty(), "Attempted to access an empty deque.");
+		return _first->value;
+	}
+
+	elem_t& back() {
+		assert(not empty(), "Attempted to access an empty deque.");
+		return _last->value;
+	}
+
+
+// Insertion ===========================================================================================================
+
+	void push_front(elem_t&& elem) {
+		this->_push_front(elem);
+	}
+
+	void push_front(const elem_t& elem) {
+		this->_push_front(elem);
+	}
+
+	template<typename...ArgsT>
+	void emplace_front(ArgsT&&...args) {
+		this->_push_front(fennec::forward<ArgsT>(args)...);
+	}
+
+	void push_back(elem_t&& elem) {
+		this->_push_back(elem);
+	}
+
+	void push_back(const elem_t& elem) {
+		this->_push_back(elem);
+	}
+
+	template<typename...ArgsT>
+	void emplace_back(ArgsT&&...args) {
+		this->_push_back(fennec::forward<ArgsT>(args)...);
+	}
+
+
+// Deletion ============================================================================================================
+
+	void clear() {
+		node* it = _first;
+		while (it) {
+			node* next = it->next;
+			fennec::destruct(it);
+			_alloc.deallocate(it);
+			it = next;
+		}
+		_first = nullptr;
+		_last  = nullptr;
+		_size  = 0;
+	}
+
+	void pop_front() {
+		if (_first == nullptr) {
+			return;
+		}
+		node* next = _first->next;
+		fennec::destruct(_first);
+		_alloc.deallocate(_first);
+		_first = next;
+		_last = next ? _last : nullptr;
+		--_size;
+	}
+
+	void pop_back() {
+		if (_last == nullptr) {
+			return;
+		}
+		node* prev = _last->prev;
+		fennec::destruct(_last);
+		_alloc.deallocate(_last);
+		_last = prev;
+		_first = prev ? _first : nullptr;
+		--_size;
+	}
+
+private:
+	alloc_t _alloc;
+	node   *_first, *_last;
+	size_t  _size;
+
+	template<typename...ArgsT>
+	void _push_front(ArgsT&&...args) {
+		node* next = _first;
+		_first = _alloc.allocate(1);
+		fennec::construct(_first, nullptr, next, fennec::forward<ArgsT>(args)...);
+		if (next) {
+			next->prev = _first;
+		} else {
+			_last = _first;
+		}
+		++_size;
+	}
+
+	template<typename...ArgsT>
+	void _push_back(ArgsT&&...args) {
+		node* prev = _last;
+		_last = _alloc.allocate(1);
+		fennec::construct(_last, prev, nullptr, fennec::forward<ArgsT>(args)...);
+		if (prev) {
+			prev->next = _last;
+		} else {
+			_first = _last;
+		}
+		++_size;
+	}
+};
+
+
+}
+
+#endif // FENNEC_CONTAINERS_DEQUE_H