refactor: add random number generation abstraction

5 files changed, 99 insertions, 27 deletions

diff --git a/src/maze.hpp b/src/maze.hpp
index e525d70..650e60a 100644
--- a/src/maze.hpp
+++ b/src/maze.hpp
@@ -2,8 +2,8 @@
 
 #include "engine/matrix.hpp"
 #include "engine/vector2.hpp"
+#include "random_generator.hpp"
 #include <memory>
-#include <random>
 #include <string>
 
 /**
@@ -16,6 +16,7 @@
  */
 template <typename Element>
 void matrix_to_maze(Matrix<Element> *matrix, std::shared_ptr<Vector2> start_pos,
-					Element space_element, std::mt19937 random_gen);
+					Element space_element,
+					std::shared_ptr<RandomNumberGenerator> random_gen);
 
 #include "maze.tpp"
diff --git a/src/maze.tpp b/src/maze.tpp
index 19390cc..2edb60d 100644
--- a/src/maze.tpp
+++ b/src/maze.tpp
@@ -22,7 +22,9 @@ std::vector<std::shared_ptr<Vector2>> get_neighbours(Matrix<Element> *matrix,
 		auto pos_down = (*pos - Vector2(0U, 2U)).copy();
 
 		if (matrix->get(*pos_down) != space_element)
+		{
 			neighbours.push_back(pos_down);
+		}
 	}
 
 	if (pos->y() != matrix->rows() - 2U)
@@ -30,7 +32,9 @@ std::vector<std::shared_ptr<Vector2>> get_neighbours(Matrix<Element> *matrix,
 		auto pos_up = (*pos + Vector2(0U, 2U)).copy();
 
 		if (matrix->get(*pos_up) != space_element)
+		{
 			neighbours.push_back(pos_up);
+		}
 	}
 
 	if (pos->x() != 1U)
@@ -38,7 +42,9 @@ std::vector<std::shared_ptr<Vector2>> get_neighbours(Matrix<Element> *matrix,
 		auto pos_left = (*pos - Vector2(2U, 0U)).copy();
 
 		if (matrix->get(*pos_left) != space_element)
+		{
 			neighbours.push_back(pos_left);
+		}
 	}
 
 	if (pos->x() != matrix->columns() - 2U)
@@ -46,7 +52,9 @@ std::vector<std::shared_ptr<Vector2>> get_neighbours(Matrix<Element> *matrix,
 		auto pos_right = (*pos + Vector2(2U, 0U)).copy();
 
 		if (matrix->get(*pos_right) != space_element)
+		{
 			neighbours.push_back(pos_right);
+		}
 	}
 
 	return neighbours;
@@ -75,14 +83,19 @@ void pos_to_between(std::shared_ptr<Vector2> between_pos, unsigned int coord,
 					unsigned int away_coord, Vector2 diff)
 {
 	if (away_coord > coord)
+	{
 		*between_pos += diff;
+	}
 	else
+	{
 		*between_pos -= diff;
+	}
 }
 
 template <typename Element>
 void matrix_to_maze(Matrix<Element> *matrix, std::shared_ptr<Vector2> start_pos,
-					Element space_element, std::mt19937 random_gen)
+					Element space_element,
+					std::shared_ptr<RandomNumberGenerator> random_gen)
 {
 	Stack<std::shared_ptr<Vector2>> path_stack(get_maze_size(matrix));
 
@@ -95,13 +108,14 @@ void matrix_to_maze(Matrix<Element> *matrix, std::shared_ptr<Vector2> start_pos,
 
 		matrix->set(*pos, space_element);
 
-		std::vector<std::shared_ptr<Vector2>> neighbours =
-			get_neighbours(matrix, pos, space_element);
+		auto neighbours = get_neighbours(matrix, pos, space_element);
 
 		if (neighbours.empty())
 		{
 			if (visited_pos_cnt == get_maze_size(matrix) - 1U)
+			{
 				break;
+			}
 
 			// Go back a step
 			path_stack.pop();
@@ -110,18 +124,20 @@ void matrix_to_maze(Matrix<Element> *matrix, std::shared_ptr<Vector2> start_pos,
 
 		visited_pos_cnt++;
 
-		auto random_dist = std::uniform_int_distribution<unsigned int>(
-			0U, static_cast<unsigned int>(neighbours.size()) - 1U);
-
-		auto next_pos = neighbours[random_dist(random_gen)];
+		auto next_pos = neighbours[random_gen->in_range(
+			0U, static_cast<unsigned int>(neighbours.size()) - 1U)];
 
 		auto between_pos = pos->copy();
 
 		if (next_pos->y() != pos->y())
+		{
 			pos_to_between(between_pos, pos->y(), next_pos->y(), Vector2(0U, 1U));
+		}
 
 		if (next_pos->x() != pos->x())
+		{
 			pos_to_between(between_pos, pos->x(), next_pos->x(), Vector2(1U, 0U));
+		}
 
 		matrix->set(*between_pos, space_element);
 
diff --git a/src/mazerator.cpp b/src/mazerator.cpp
index 33ef1b1..b30124f 100644
--- a/src/mazerator.cpp
+++ b/src/mazerator.cpp
@@ -2,10 +2,10 @@
 #include "engine/vector2.hpp"
 #include "getopt.h"
 #include "maze.hpp"
+#include "random_generator.hpp"
 #include "utils.hpp"
 #include <iostream>
 #include <memory>
-#include <random>
 #include <string>
 
 void optarg_error(int arg, std::string error)
@@ -19,11 +19,15 @@ void validate_start_coords(unsigned int start_x, unsigned int start_y, unsigned
 						   unsigned int height)
 {
 	if (start_x >= width)
+	{
 		throw "The x start coordinate cannot be higher than or equal to the maze's width";
+	}
 
 	if (start_y >= height)
+	{
 		throw "The y start coordinate cannot be higher than or equal to the maze's "
 			  "height";
+	}
 }
 
 /**
@@ -40,7 +44,9 @@ void parse_uint_arg(unsigned int *num_dst, int arg, bool check_zero = false)
 		*num_dst = str_to_uint(std::string(optarg));
 
 		if (check_zero && *num_dst == 0)
+		{
 			throw "It should not be 0";
+		}
 	}
 	catch (const char *error)
 	{
@@ -62,10 +68,10 @@ int main(int argc, char *argv[])
 	unsigned int maze_width = 40U;
 	unsigned int maze_height = 20U;
 
-	std::shared_ptr<unsigned int> start_x = nullptr;
-	std::shared_ptr<unsigned int> start_y = nullptr;
+	std::unique_ptr<unsigned int> start_x = nullptr;
+	std::unique_ptr<unsigned int> start_y = nullptr;
 
-	std::unique_ptr<std::mt19937> random_gen = nullptr;
+	std::shared_ptr<RandomNumberGenerator> random_gen = nullptr;
 
 	std::string wall = "█";
 
@@ -81,11 +87,11 @@ int main(int argc, char *argv[])
 			parse_uint_arg(&maze_height, arg, true);
 			break;
 		case 'x':
-			start_x = std::make_shared<unsigned int>();
+			start_x = std::make_unique<unsigned int>();
 			parse_uint_arg(start_x.get(), arg);
 			break;
 		case 'y':
-			start_y = std::make_shared<unsigned int>();
+			start_y = std::make_unique<unsigned int>();
 			parse_uint_arg(start_y.get(), arg);
 			break;
 		case 'W':
@@ -95,7 +101,7 @@ int main(int argc, char *argv[])
 			unsigned int seed;
 			parse_uint_arg(&seed, arg, true);
 
-			random_gen = std::make_unique<std::mt19937>(seed);
+			random_gen = std::make_shared<RandomNumberGenerator>(seed);
 			break;
 		case 0:
 			std::cout
@@ -126,24 +132,19 @@ int main(int argc, char *argv[])
 
 	if (random_gen == nullptr)
 	{
-		std::random_device random_device;
-		random_gen = std::make_unique<std::mt19937>(random_device());
+		random_gen = std::make_shared<RandomNumberGenerator>();
 	}
 
 	if (start_x == nullptr)
 	{
-		auto random_dist =
-			std::uniform_int_distribution<unsigned int>(0, maze_width - 1U);
-
-		start_x = std::make_unique<unsigned int>(random_dist(*random_gen));
+		start_x =
+			std::make_unique<unsigned int>(random_gen->in_range(0, maze_width - 1U));
 	}
 
 	if (start_y == nullptr)
 	{
-		auto random_dist =
-			std::uniform_int_distribution<unsigned int>(0, maze_height - 1U);
-
-		start_y = std::make_unique<unsigned int>(random_dist(*random_gen));
+		start_y =
+			std::make_unique<unsigned int>(random_gen->in_range(0, maze_height - 1U));
 	}
 
 	try
@@ -162,7 +163,7 @@ int main(int argc, char *argv[])
 
 	auto start_pos = std::make_shared<Vector2>(*start_x * 2U + 1U, *start_y * 2U + 1U);
 
-	matrix_to_maze<std::string>(&matrix, start_pos, " ", *random_gen);
+	matrix_to_maze<std::string>(&matrix, start_pos, " ", random_gen);
 
 	matrix.print();
 }
diff --git a/src/random_generator.cpp b/src/random_generator.cpp
new file mode 100644
index 0000000..1f17a88
--- /dev/null
+++ b/src/random_generator.cpp
@@ -0,0 +1,20 @@
+#include "random_generator.hpp"
+
+RandomNumberGenerator::RandomNumberGenerator(unsigned int seed)
+{
+	this->_generator = std::make_unique<std::mt19937>(seed);
+}
+
+RandomNumberGenerator::RandomNumberGenerator()
+{
+	std::random_device random_device;
+
+	this->_generator = std::make_unique<std::mt19937>(random_device());
+}
+
+unsigned int RandomNumberGenerator::in_range(unsigned int a, unsigned int b)
+{
+	auto random_distribution = std::uniform_int_distribution<unsigned int>(a, b);
+
+	return random_distribution(*this->_generator);
+}
diff --git a/src/random_generator.hpp b/src/random_generator.hpp
new file mode 100644
index 0000000..a4c1331
--- /dev/null
+++ b/src/random_generator.hpp
@@ -0,0 +1,34 @@
+#pragma once
+
+#include <memory>
+#include <random>
+
+/**
+ * Pseudo-random unsigned integer generator.
+ */
+class RandomNumberGenerator
+{
+public:
+	/**
+	 * Creates a pseudo-random number generator.
+	 *
+	 * @param seed A number generation seed
+	 */
+	RandomNumberGenerator(unsigned int seed);
+
+	/**
+	 * Creates a pesudo-random number generator.
+	 */
+	RandomNumberGenerator();
+
+	/**
+	 * Generates a number in the range of a to b.
+	 *
+	 * @param a A number lower than b
+	 * @param b A number greater than a
+	 */
+	unsigned int in_range(unsigned int a, unsigned int b);
+
+private:
+	std::unique_ptr<std::mt19937> _generator;
+};