9 files changed, 430 insertions, 71 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 66bad3a..1dfce91 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -9,3 +9,7 @@ project(game-of-life CXX)
 
 add_subdirectory(lib)
 add_subdirectory(src)
+
+if("${TESTING}")
+	add_subdirectory(test)
+endif()
diff --git a/src/engine/graphics/string_matrix.cpp b/src/engine/graphics/string_matrix.cpp
index ae06755..3920b8e 100644
--- a/src/engine/graphics/string_matrix.cpp
+++ b/src/engine/graphics/string_matrix.cpp
@@ -1,30 +1,59 @@
 #include "string_matrix.hpp"
 
+#include <iostream>
+#include <ranges>
+
 StringMatrix::StringMatrix(const Bounds &bounds) noexcept
-	: _rows(bounds.get_height()), _columns(bounds.get_width())
+	: _matrix(new std::string_view *[bounds.get_height()]),
+	  _row_cnt(bounds.get_height()),
+	  _column_cnt(bounds.get_width())
 {
-	_matrix.reserve(bounds.get_height());
-	_matrix.assign(_matrix.capacity(), std::vector<std::string_view>(bounds.get_width()));
+	for (gsl::owner<std::string_view **> row = _matrix; row != _matrix + _row_cnt; row++)
+	{
+		*row = static_cast<gsl::owner<std::string_view *>>(
+			new std::string_view[bounds.get_width()]);
+	}
 };
 
+StringMatrix::StringMatrix(const StringMatrix &string_matrix) noexcept
+	: _matrix(new std::string_view *[string_matrix._row_cnt]),
+	  _row_cnt(string_matrix._row_cnt),
+	  _column_cnt(string_matrix._column_cnt)
+{
+	_copy_matrix_from(string_matrix);
+}
+
+StringMatrix::StringMatrix(StringMatrix &&string_matrix) noexcept
+	: _matrix(string_matrix._matrix),
+	  _row_cnt(string_matrix._row_cnt),
+	  _column_cnt(string_matrix._column_cnt)
+{
+	string_matrix._matrix = nullptr;
+}
+
+StringMatrix::~StringMatrix() noexcept
+{
+	_delete_matrix();
+}
+
 void StringMatrix::fill(std::string_view element) noexcept
 {
-	for (uint32_t row = 0U; row < _matrix.capacity(); row++)
+	for (auto row : *this)
 	{
-		std::vector<std::string_view> row_vector = _matrix[row];
-
-		for (uint32_t column = 0U; column < row_vector.capacity(); column++)
+		for (auto &col : row)
 		{
-			_matrix[row][column] = element;
+			col = element;
 		}
 	}
 }
 
 std::string_view StringMatrix::get(const Vector2 &pos) const noexcept
 {
+
 	auto x = static_cast<std::size_t>(pos.get_x());
 	auto y = static_cast<std::size_t>(pos.get_y());
 
+	// NOLINTNEXTLINE(cppcoreguidelines-pro-bounds-pointer-arithmetic)
 	return _matrix[y][x];
 }
 
@@ -33,15 +62,79 @@ void StringMatrix::set(const Vector2 &pos, std::string_view element) noexcept
 	auto x = static_cast<std::size_t>(pos.get_x());
 	auto y = static_cast<std::size_t>(pos.get_y());
 
+	// NOLINTNEXTLINE(cppcoreguidelines-pro-bounds-pointer-arithmetic)
 	_matrix[y][x] = element;
 }
 
-uint32_t StringMatrix::rows() const noexcept
+uint32_t StringMatrix::get_row_cnt() const noexcept
+{
+	return _row_cnt;
+}
+
+uint32_t StringMatrix::get_column_cnt() const noexcept
+{
+	return _column_cnt;
+}
+
+MatrixIterator<std::string_view> StringMatrix::begin() const noexcept
+{
+	return MatrixIterator(_matrix, _column_cnt);
+}
+
+MatrixIterator<std::string_view> StringMatrix::end() const noexcept
 {
-	return _rows;
+	return MatrixIterator(_matrix + _row_cnt, _column_cnt);
 }
 
-uint32_t StringMatrix::columns() const noexcept
+StringMatrix &StringMatrix::operator=(const StringMatrix &rhs) noexcept
 {
-	return _columns;
+	if (&rhs != this)
+	{
+		_delete_matrix();
+		_matrix = nullptr;
+
+		_matrix = new std::string_view *[rhs._row_cnt];
+		_copy_matrix_from(rhs);
+	}
+
+	return *this;
+}
+
+StringMatrix &StringMatrix::operator=(StringMatrix &&rhs) noexcept
+{
+	if (&rhs != this)
+	{
+		_delete_matrix();
+		_matrix = rhs._matrix;
+		rhs._matrix = nullptr;
+	}
+
+	return *this;
+}
+
+void StringMatrix::_delete_matrix() noexcept
+{
+	for (gsl::owner<std::string_view **> row = _matrix; row != _matrix + _row_cnt; row++)
+	{
+		delete[](*row);
+	}
+
+	delete[] _matrix;
+}
+
+void StringMatrix::_copy_matrix_from(const StringMatrix &source) noexcept
+{
+	gsl::owner<std::string_view **> source_row = source._matrix;
+
+	for (gsl::owner<std::string_view **> row = _matrix; row != _matrix + _row_cnt;
+		 row++, source_row++)
+	{
+		*row = static_cast<gsl::owner<std::string_view *>>(
+			new std::string_view[_column_cnt]);
+
+		// NOLINTNEXTLINE(cppcoreguidelines-pro-bounds-pointer-arithmetic)
+		auto *end = *source_row + _column_cnt;
+
+		std::copy(*source_row, end, *row);
+	}
 }
diff --git a/src/engine/graphics/string_matrix.hpp b/src/engine/graphics/string_matrix.hpp
index 40fbb11..ff0939c 100644
--- a/src/engine/graphics/string_matrix.hpp
+++ b/src/engine/graphics/string_matrix.hpp
@@ -4,58 +4,49 @@
 
 #include "engine/data/bounds.hpp"
 #include "engine/data/vector2.hpp"
+#include "engine/matrix_iterator.hpp"
 
+#include <gsl/pointers>
+#include <memory>
 #include <string_view>
 #include <vector>
 
-/**
- * A Matrix.
- */
 class StringMatrix : public IMatrix<std::string_view>
 {
 public:
-	/**
-	 * Creates a matrix.
-	 *
-	 * @param bounds The bounds of the matrix
-	 */
 	explicit StringMatrix(const Bounds &bounds) noexcept;
 
-	/**
-	 * Fills the matrix with a element.
-	 *
-	 * @param element A element
-	 */
+	StringMatrix(const StringMatrix &string_matrix) noexcept;
+
+	StringMatrix(StringMatrix &&string_matrix) noexcept;
+
+	~StringMatrix() noexcept override;
+
 	void fill(std::string_view element) noexcept override;
 
-	/**
-	 * Returns a element of the matrix.
-	 *
-	 * @param pos The position of a element
-	 */
 	[[nodiscard]] std::string_view get(const Vector2 &pos) const noexcept override;
 
-	/**
-	 * Sets a element of the matrix.
-	 *
-	 * @param pos The position of a element
-	 * @param element A new element
-	 */
 	void set(const Vector2 &pos, std::string_view element) noexcept override;
 
-	/**
-	 * Returns the number of rows the matrix has.
-	 */
-	[[nodiscard]] uint32_t rows() const noexcept override;
+	[[nodiscard]] uint32_t get_row_cnt() const noexcept override;
+
+	[[nodiscard]] uint32_t get_column_cnt() const noexcept override;
+
+	[[nodiscard]] MatrixIterator<std::string_view> begin() const noexcept override;
 
-	/**
-	 * Returns the number of columns the matrix has.
-	 */
-	[[nodiscard]] uint32_t columns() const noexcept override;
+	[[nodiscard]] MatrixIterator<std::string_view> end() const noexcept override;
+
+	StringMatrix &operator=(const StringMatrix &rhs) noexcept;
+
+	StringMatrix &operator=(StringMatrix &&rhs) noexcept;
 
 private:
-	std::vector<std::vector<std::string_view>> _matrix;
+	gsl::owner<std::string_view **> _matrix;
+
+	uint32_t _row_cnt;
+	uint32_t _column_cnt;
+
+	void _delete_matrix() noexcept;
 
-	uint32_t _rows;
-	uint32_t _columns;
+	void _copy_matrix_from(const StringMatrix &source) noexcept;
 };
diff --git a/src/engine/matrix_iterator.hpp b/src/engine/matrix_iterator.hpp
new file mode 100644
index 0000000..5d35052
--- /dev/null
+++ b/src/engine/matrix_iterator.hpp
@@ -0,0 +1,65 @@
+#pragma once
+
+#include <gsl/pointers>
+
+template <typename Element>
+class MatrixRowIterator
+{
+public:
+	using ColumnPtr = gsl::owner<Element *>;
+
+	explicit MatrixRowIterator(ColumnPtr column_ptr) noexcept;
+
+	MatrixRowIterator &operator++() noexcept;
+	MatrixRowIterator operator++(int) noexcept;
+
+	Element &operator*() const noexcept;
+
+	bool operator==(const MatrixRowIterator &rhs) const noexcept;
+	bool operator!=(const MatrixRowIterator &rhs) const noexcept;
+
+private:
+	ColumnPtr _column_ptr;
+};
+
+template <typename Element>
+class MatrixRow
+{
+public:
+	using RowPtr = gsl::owner<Element *>;
+
+	explicit MatrixRow(RowPtr row_ptr, const uint32_t &column_cnt) noexcept;
+
+	[[nodiscard]] MatrixRowIterator<Element> begin() const noexcept;
+
+	[[nodiscard]] MatrixRowIterator<Element> end() const noexcept;
+
+private:
+	RowPtr _row_ptr;
+
+	const uint32_t &_column_cnt;
+};
+
+template <typename Element>
+class MatrixIterator
+{
+public:
+	using RowPtr = gsl::owner<Element **>;
+
+	explicit MatrixIterator(RowPtr row_ptr, const uint32_t &column_cnt) noexcept;
+
+	MatrixIterator &operator++() noexcept;
+	MatrixIterator operator++(int) noexcept;
+
+	MatrixRow<Element> operator*() const noexcept;
+
+	bool operator==(const MatrixIterator &rhs) const noexcept;
+	bool operator!=(const MatrixIterator &rhs) const noexcept;
+
+private:
+	RowPtr _row_ptr;
+
+	const uint32_t &_column_cnt;
+};
+
+#include "matrix_iterator.tpp"
diff --git a/src/engine/matrix_iterator.tpp b/src/engine/matrix_iterator.tpp
new file mode 100644
index 0000000..52952c9
--- /dev/null
+++ b/src/engine/matrix_iterator.tpp
@@ -0,0 +1,112 @@
+#pragma once
+
+#include "matrix_iterator.hpp"
+
+// Matrix row iterator
+
+template <typename Element>
+MatrixRowIterator<Element>::MatrixRowIterator(ColumnPtr column_ptr) noexcept
+	: _column_ptr(column_ptr)
+{
+}
+
+template <typename Element>
+MatrixRowIterator<Element> &MatrixRowIterator<Element>::operator++() noexcept
+{
+	++_column_ptr;
+
+	return *this;
+}
+
+template <typename Element>
+MatrixRowIterator<Element> MatrixRowIterator<Element>::operator++(int) noexcept
+{
+	auto copy = *this;
+
+	++(*this);
+
+	return copy;
+}
+
+template <typename Element>
+Element &MatrixRowIterator<Element>::operator*() const noexcept
+{
+	return *_column_ptr;
+}
+
+template <typename Element>
+bool MatrixRowIterator<Element>::operator==(const MatrixRowIterator &rhs) const noexcept
+{
+	return _column_ptr == rhs._column_ptr;
+}
+
+template <typename Element>
+bool MatrixRowIterator<Element>::operator!=(const MatrixRowIterator &rhs) const noexcept
+{
+	return _column_ptr != rhs._column_ptr;
+}
+
+// Matrix row
+
+template <typename Element>
+MatrixRow<Element>::MatrixRow(RowPtr row_ptr, const uint32_t &column_cnt) noexcept
+	: _row_ptr(row_ptr), _column_cnt(column_cnt)
+{
+}
+
+template <typename Element>
+MatrixRowIterator<Element> MatrixRow<Element>::begin() const noexcept
+{
+	return MatrixRowIterator<Element>(_row_ptr);
+}
+
+template <typename Element>
+MatrixRowIterator<Element> MatrixRow<Element>::end() const noexcept
+{
+	return MatrixRowIterator<Element>(_row_ptr + _column_cnt);
+}
+
+// Matrix iterator
+
+template <typename Element>
+MatrixIterator<Element>::MatrixIterator(RowPtr row_ptr,
+										const uint32_t &column_cnt) noexcept
+	: _row_ptr(row_ptr), _column_cnt(column_cnt)
+{
+}
+
+template <typename Element>
+MatrixIterator<Element> &MatrixIterator<Element>::operator++() noexcept
+{
+	++_row_ptr;
+
+	return *this;
+}
+
+template <typename Element>
+MatrixIterator<Element> MatrixIterator<Element>::operator++(int) noexcept
+{
+	auto copy = *this;
+
+	++(*this);
+
+	return copy;
+}
+
+template <typename Element>
+MatrixRow<Element> MatrixIterator<Element>::operator*() const noexcept
+{
+	return MatrixRow(*_row_ptr, _column_cnt);
+}
+
+template <typename Element>
+bool MatrixIterator<Element>::operator==(const MatrixIterator &rhs) const noexcept
+{
+	return _row_ptr == rhs._row_ptr;
+}
+
+template <typename Element>
+bool MatrixIterator<Element>::operator!=(const MatrixIterator &rhs) const noexcept
+{
+	return _row_ptr != rhs._row_ptr;
+}
diff --git a/src/interfaces/matrix.hpp b/src/interfaces/matrix.hpp
index 44a26ed..c22c0a7 100644
--- a/src/interfaces/matrix.hpp
+++ b/src/interfaces/matrix.hpp
@@ -3,45 +3,39 @@
 #include "engine/data/bounds.hpp"
 #include "engine/data/vector2.hpp"
 
+#include "engine/matrix_iterator.hpp"
+
 #include <memory>
 
 template <typename Element>
 class IMatrix
 {
 public:
+	IMatrix() noexcept = default;
+
+	IMatrix(const IMatrix &matrix) noexcept = default;
+
+	IMatrix(IMatrix &&matrix) noexcept = default;
+
 	virtual ~IMatrix() noexcept = default;
 
-	/**
-	 * Fills the matrix with a element.
-	 *
-	 * @param element A element
-	 */
 	virtual void fill(Element element) noexcept = 0;
 
-	/**
-	 * Returns a element of the matrix.
-	 *
-	 * @param pos The position of a element
-	 */
 	[[nodiscard]] virtual Element get(const Vector2 &pos) const noexcept = 0;
 
-	/**
-	 * Sets a element of the matrix.
-	 *
-	 * @param pos The position of a element
-	 * @param element A new element
-	 */
 	virtual void set(const Vector2 &pos, Element element) noexcept = 0;
 
-	/**
-	 * Returns the number of rows the matrix has.
-	 */
-	[[nodiscard]] virtual uint32_t rows() const noexcept = 0;
+	[[nodiscard]] virtual uint32_t get_row_cnt() const noexcept = 0;
+
+	[[nodiscard]] virtual uint32_t get_column_cnt() const noexcept = 0;
+
+	[[nodiscard]] virtual MatrixIterator<std::string_view> begin() const noexcept = 0;
+
+	[[nodiscard]] virtual MatrixIterator<std::string_view> end() const noexcept = 0;
+
+	IMatrix &operator=(const IMatrix &matrix) noexcept = default;
 
-	/**
-	 * Returns the number of columns the matrix has.
-	 */
-	[[nodiscard]] virtual uint32_t columns() const noexcept = 0;
+	IMatrix &operator=(IMatrix &&matrix) noexcept = default;
 };
 
 template <typename Element>
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
new file mode 100644
index 0000000..ac84f42
--- /dev/null
+++ b/test/CMakeLists.txt
@@ -0,0 +1,45 @@
+file(GLOB SOURCES
+	main.cpp
+	string_matrix.test.cpp
+	${CMAKE_SOURCE_DIR}/src/engine/data/vector2.cpp
+	${CMAKE_SOURCE_DIR}/src/engine/data/bounds.cpp
+	${CMAKE_SOURCE_DIR}/src/engine/graphics/string_matrix.cpp
+)
+
+add_executable(tests ${SOURCES})
+
+target_compile_features(tests PUBLIC cxx_std_20)
+
+target_compile_options(
+	tests
+	PRIVATE
+	-Wall -Wextra -Wpedantic -Wshadow
+	-Wold-style-cast -Wcast-align -Wno-unused
+	-Wconversion -Wcast-qual -Wctor-dtor-privacy
+	-Wdisabled-optimization -Wformat=2 -Winit-self
+	-Wmissing-declarations -Wmissing-include-dirs
+	-Woverloaded-virtual -Wredundant-decls
+	-Wsign-conversion -Wsign-promo
+	-Wstrict-overflow=5 -Wswitch-default
+	-Wundef -Werror
+	-pedantic -fsanitize=address -fno-exceptions
+)
+
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+	target_compile_options(
+		tests
+		PRIVATE
+		-Wlogical-op -Wnoexcept -Wstrict-null-sentinel
+	)
+endif()
+
+target_include_directories(
+	tests
+	PRIVATE
+	"${CMAKE_SOURCE_DIR}/src"
+	"${CMAKE_SOURCE_DIR}/test"
+)
+
+target_link_libraries(tests GSL doctest)
+
+target_link_options(tests PRIVATE -fsanitize=address)
diff --git a/test/main.cpp b/test/main.cpp
new file mode 100644
index 0000000..0a3f254
--- /dev/null
+++ b/test/main.cpp
@@ -0,0 +1,2 @@
+#define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
+#include <doctest/doctest.h>
diff --git a/test/string_matrix.test.cpp b/test/string_matrix.test.cpp
new file mode 100644
index 0000000..522a274
--- /dev/null
+++ b/test/string_matrix.test.cpp
@@ -0,0 +1,53 @@
+#include "engine/graphics/string_matrix.hpp"
+#include "engine/data/bounds.hpp"
+
+#include <doctest/doctest.h>
+#include <type_traits>
+
+constexpr uint32_t MATRIX_WIDTH = 76;
+constexpr uint32_t MATRIX_HEIGHT = 31;
+
+TEST_CASE("String matrix")
+{
+	auto string_matrix =
+		StringMatrix(Bounds({.width = MATRIX_WIDTH, .height = MATRIX_HEIGHT}));
+
+	SUBCASE("Can set & get elements")
+	{
+		// NOLINTNEXTLINE(cppcoreguidelines-avoid-magic-numbers,readability-magic-numbers)
+		const auto position = Vector2({.x = 56, .y = 20});
+
+		string_matrix.set(position, "#");
+
+		CHECK(string_matrix.get(position) == "#");
+	}
+
+	SUBCASE("Can iterate")
+	{
+		CHECK(std::is_same_v<decltype(string_matrix.begin()),
+							 MatrixIterator<std::string_view>>);
+
+		CHECK(std::is_same_v<decltype(string_matrix.end()),
+							 MatrixIterator<std::string_view>>);
+
+		uint32_t row_iter_cnt = 0;
+
+		for (auto row : string_matrix)
+		{
+			row_iter_cnt++;
+
+			CHECK(std::is_same_v<decltype(row), MatrixRow<std::string_view>>);
+
+			uint32_t col_iter_cnt = 0;
+
+			for (auto &col : row)
+			{
+				col_iter_cnt++;
+			}
+
+			CHECK(col_iter_cnt == MATRIX_WIDTH);
+		}
+
+		CHECK(row_iter_cnt == MATRIX_HEIGHT);
+	}
+}