From 1fbcbc2e31fa3fe4fd513cc3968bc09f83d95917 Mon Sep 17 00:00:00 2001
From: Matthew Ellison <m_ellison@ymail.com>
Date: Mon, 30 Apr 2018 00:58:11 -0400
Subject: [PATCH] Created the Vigenere class for Vigenere Ciphers

---
 Headers/Vigenere.hpp     |  37 +++++++++++
 SourceFiles/Vigenere.cpp | 139 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 176 insertions(+)
 create mode 100644 Headers/Vigenere.hpp
 create mode 100644 SourceFiles/Vigenere.cpp

diff --git a/Headers/Vigenere.hpp b/Headers/Vigenere.hpp
new file mode 100644
index 0000000..ea4344d
--- /dev/null
+++ b/Headers/Vigenere.hpp
@@ -0,0 +1,37 @@
+//Ciphers/SourceFiles/Vigenere.hpp
+//Matthew Ellison
+// Created:	4-29-18
+//Modified; 4-29-18
+//This file contains the declaration of the Vigenere class
+
+#ifndef VIGENERE_HPP
+#define VIGENERE_HPP
+
+
+#include <string>
+#include <vector>
+
+class Vigenere{
+private:
+	std::string inputString;    //This is the string that you want to encode or decode
+	std::string outputString;   //This is the string that is output from encoding or decoding
+	std::string keyword;        //This is the keyword that is the resposible for determining the offsets that you change each character by
+	std::vector<unsigned int> offset;   //This holds the offsets computed from each character in the keyword
+	void setOffset();
+public:
+	Vigenere();
+	~Vigenere();
+	void setInputString(std::string input);
+	std::string getInputString() const;
+	std::string getOutputString() const;
+	void setKeyword(std::string key);	
+	std::string getKeyword() const;
+	std::vector<unsigned int> getOffsets() const;
+	std::string encode();
+	std::string encode(std::string key, std::string input);
+	std::string decode();
+	std::string decode(std::string key, std::string input);
+	void reset();
+};
+
+#endif //VIGENERE_HPP
diff --git a/SourceFiles/Vigenere.cpp b/SourceFiles/Vigenere.cpp
new file mode 100644
index 0000000..de50f56
--- /dev/null
+++ b/SourceFiles/Vigenere.cpp
@@ -0,0 +1,139 @@
+//Ciphers/SourceFiles/Vigenere.cpp
+//Matthew Ellison
+// Created: 4-29-18
+//Modified; 4-29-18
+//This file contains the implementation of the Vigenere class
+
+#include "../Headers/Vigenere.hpp"
+#include <string>
+#include <vector>
+#include <cctype>
+
+
+Vigenere::Vigenere(){
+}
+
+Vigenere::~Vigenere(){
+}
+
+void Vigenere::setInputString(std::string input){
+	//Make sure inputString is clear
+	inputString = "";
+
+	//Loop through every character in input. Remove all whitespace and punctuation and make sure all letters are capital and add it to inputString
+	for(int cnt = 0;cnt < input.size();++cnt){
+		char letter = input[cnt];
+		if(isupper(letter)){
+			inputString += letter;
+		}
+		else if(islower(letter)){
+			inputString += toupper(letter);
+		}
+		//If the letter is whitespace or punctuation do nothing
+	}
+}
+
+std::string Vigenere::getInputString() const{
+	return inputString;
+}
+
+std::string Vigenere::getOutputString() const{
+	return outputString;
+}
+
+void Vigenere::setKeyword(std::string key){
+	//Make sure the keyword is blank
+	keyword = "";
+	//Loop through every letter in the key and make sure all of them are uppercase letters
+	for(int cnt = 0;cnt < key.size();++cnt){
+		char letter = key[cnt];
+		if(isupper(letter)){
+			keyword += letter;
+		}
+		else if(islower(letter)){
+			keyword += toupper(letter);
+		}
+		//If it is not a letter ignore it
+	}
+	setOffset();
+}
+
+std::string Vigenere::getKeyword() const{
+	return keyword;
+}
+
+void Vigenere::setOffset(){
+	//Make sure offset is empty
+	offset.clear();
+	//Reserve the correct size to increase speed later
+	offset.reserve(keyword.size());
+
+	//Loop through every letter in keyword and get the offset from A
+	for(char letter : keyword){
+		offset.push_back((letter - 'A') % 26);
+	}
+}
+
+std::vector<unsigned int> Vigenere::getOffsets() const{
+	return offset;
+}
+
+std::string Vigenere::encode(){
+	//Clear the outputString
+	outputString = "";
+	//Reserve the correct size for the output string to increase speed for longer messages
+	outputString.reserve(inputString.size());
+
+	//Step through every charater in the inputString and advance it the correct amount, according to offset
+	for(int cnt = 0;cnt < inputString.size();++cnt){
+		char letter = (inputString[cnt] + offset[cnt % offset.size()]);	//By using % you allow it to loop without having a separate counter
+		//Make sure the character is still a letter, if not, wrap around
+		if(letter < 'A'){
+			letter += 26;
+		}
+		else if(letter > 'Z'){
+			letter -= 26;
+		}
+		outputString += letter;
+	}
+
+	return outputString;
+}
+
+std::string Vigenere::encode(std::string key, std::string input){
+	setKeyword(key);
+	setInputString(input);
+	return encode();
+}
+
+std::string Vigenere::decode(){
+	//Clear the outputString
+	outputString = "";
+	//Reserve the correct size for the output string to increase speed for longer messages
+	outputString.reserve(inputString.size());
+
+	//Step through every charater in the inputString and reduce it the correct amount, according to offset
+	for(int cnt = 0;cnt < inputString.size();++cnt){
+		char letter = (inputString[cnt] - offset[cnt % offset.size()]);	//By using % you allow it to loop without having a separate counter
+		if(letter < 'A'){
+			letter += 26;
+		}
+		else if(letter > 'Z'){
+			letter -= 26;
+		}
+		outputString += letter;
+	}
+
+	return outputString;
+}
+
+std::string Vigenere::decode(std::string key, std::string input){
+	setKeyword(key);
+	setInputString(input);
+	return decode();
+}
+
+void Vigenere::reset(){
+	inputString = outputString = keyword = "";
+	offset.clear();
+}