From 918909c1fa46a390f286325671c891992e56dca2 Mon Sep 17 00:00:00 2001
From: Trianta <56975502+Trimutex@users.noreply.github.com>
Date: Thu, 7 Dec 2023 21:36:51 -0600
Subject: [PATCH] Added checking arguments and a help message

---
 src/generator.cpp | 40 ++++++++++++++++++++++++++++++++++++++++
 src/generator.hpp | 19 ++++++++++++++++---
 src/main.cpp      |  4 ++++
 3 files changed, 60 insertions(+), 3 deletions(-)

diff --git a/src/generator.cpp b/src/generator.cpp
index e69de29..3f32cdb 100644
--- a/src/generator.cpp
+++ b/src/generator.cpp
@@ -0,0 +1,40 @@
+#include "generator.hpp"
+#include <iostream>
+
+void Generator::SetArguments(int argc, char* argv[]) {
+    std::string tempStr;
+    for (int i = 1; i < argc; ++i) {
+        tempStr.assign(argv[i]);
+        if (tempStr == "-i") {
+            setup.isFileSet = true;
+            ++i;
+            setup.filename.assign(argv[i]);
+        }
+        if (tempStr == "-k") {
+            setup.isPrefixSet = true;
+            ++i;
+            setup.prefixLength = std::stoi(argv[i]);
+        }
+        if (tempStr == "-n") {
+            setup.isOutputSet = true;
+            ++i;
+            setup.outputLength = std::stoi(argv[i]);
+        }
+        if (tempStr == "-h") {
+            PrintUsage();
+            exit(0);
+        }
+    }
+    if (!setup.isFileSet) { std::cerr << "[Setup - Error] Filename not specified" << std::endl; }
+    if (!setup.prefixLength) { std::cerr << "[Setup - Error] Prefix length not specified" << std::endl; }
+    if (!setup.outputLength) { std::cerr << "[Setup - Error] Output length not specified" << std::endl; }
+    if (!setup.isFileSet || !setup.isPrefixSet || !setup.isOutputSet) { PrintUsage(); }
+}
+
+void PrintUsage(void) {
+    std::cout << "Usage:  markov -i input_file -k prefix_length -n output_length" << std::endl;
+    std::cout << "        -i: Direct path to input file for basis" << std::endl;
+    std::cout << "        -k: Prefix length for Markov chain" << std::endl;
+    std::cout << "        -n: Length of output to be generated (words)" << std::endl;
+    std::cout << "        -h: Prints this usage text" << std::endl;
+}
diff --git a/src/generator.hpp b/src/generator.hpp
index b4d95bd..a50313b 100644
--- a/src/generator.hpp
+++ b/src/generator.hpp
@@ -1,13 +1,26 @@
 #ifndef GENERATOR_HPP
 #define GENERATOR_HPP
 
+#include <string>
+
+void PrintUsage(void);
+
+struct ArgumentList {
+    std::string filename = "";
+    bool isFileSet = false;
+    int prefixLength = 0;
+    bool isPrefixSet = false;
+    int outputLength = 0;
+    bool isOutputSet = false;
+};
+
 struct Generator {
 public:
-    Generator(void);
+    Generator(void) = default;
+    ~Generator(void) = default;
     void SetArguments(int argc, char* argv[]);
 private:
-    int prefixLength = 0;
-    int outputLength = 0;
+    ArgumentList setup;
 };
 
 #endif // !GENERATOR_HPP
diff --git a/src/main.cpp b/src/main.cpp
index aba9d35..6997419 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,6 +1,10 @@
 #include "generator.hpp"
 
 int main(int argc, char* argv[]) {
+    if (argc == 1) { 
+        PrintUsage(); 
+        exit(0); 
+    }
     Generator markovChain;
     markovChain.SetArguments(argc, argv);
     return 0;