refactor: use dependency injection

1 files changed, 100 insertions, 0 deletions

diff --git a/src/argument_parser.cpp b/src/argument_parser.cpp
new file mode 100644
index 0000000..b5f14bc
--- /dev/null
+++ b/src/argument_parser.cpp
@@ -0,0 +1,100 @@
+#include "argument_parser.hpp"
+
+#include "conversion.hpp"
+#include "interfaces/randomization.hpp"
+
+#include <cstdlib>
+#include <iostream>
+#include <string_view>
+
+namespace
+{
+void optarg_error(char arg, const std::string_view &error)
+{
+	std::cout << "Error: Invalid option argument for -" << arg << ". " << error
+			  << std::endl;
+	exit(EXIT_FAILURE);
+}
+
+/**
+ * Returns the current optarg as a string view.
+ */
+std::string_view get_str_optarg()
+{
+	return std::string_view(optarg);
+}
+
+/**
+ * Returns the current optarg as a unsigned integer.
+ *
+ * @param arg The current command-line argument character
+ * @param check_zero Whether or not to make sure that the result is not zero
+ */
+unsigned int get_uint_optarg(char arg, bool check_zero = false)
+{
+	auto conversion_result = str_to_uint(get_str_optarg());
+
+	if (!conversion_result.success || (check_zero && conversion_result.result == 0))
+	{
+		optarg_error(arg, conversion_result.fail_reason);
+	}
+
+	return conversion_result.result;
+}
+} // namespace
+
+ArgumentParser::ArgumentParser(
+	IRandomNumberGeneratorFactory random_number_generator_factory)
+	: _random_number_generator_factory(std::move(random_number_generator_factory))
+{
+}
+
+ParsedArguments
+ArgumentParser::parse(const std::vector<option> &options,
+					  const std::string_view &short_options, const int &argc,
+					  char *const *argv) // NOLINT(cppcoreguidelines-avoid-c-arrays,
+										 // modernize-avoid-c-arrays)
+{
+	// NOLINTNEXTLINE(cppcoreguidelines-pro-bounds-pointer-arithmetic)
+	const auto args = std::vector<std::string_view>(argv, argv + argc);
+
+	const auto program_name = args[0];
+
+	ParsedArguments parsed_arguments;
+
+	char arg = 0;
+	while ((arg = static_cast<char>(getopt_long(argc, argv, short_options.data(),
+												options.data(), nullptr))) != -1)
+	{
+		switch (arg)
+		{
+		case 's':
+		{
+			auto seed = get_uint_optarg(arg, true);
+
+			parsed_arguments.random_gen = _random_number_generator_factory(seed);
+			break;
+		}
+		case 'h':
+		{
+			std::cout << "Usage: " << program_name
+					  << " [OPTION]...\n\n"
+						 "Options:\n"
+					  << "  -s, --seed SEED         The randomization seed used\n"
+						 "  -h  --help              Displays usage information"
+					  << std::endl;
+			exit(EXIT_SUCCESS);
+		}
+		case '?':
+		{
+			std::cout << "\nTry '" << program_name << " --help' for more information"
+					  << std::endl;
+			exit(EXIT_FAILURE);
+		}
+		default:
+			abort();
+		}
+	}
+
+	return parsed_arguments;
+}