Implemented IPv6 address decoding algorithm

connect_code.cpp

@@ -1,6 +1,7 @@
 #include <iostream>
 #include <string>
 #include <vector>
+#include <algorithm>
 #include <iomanip>
 #include <cstring>
 #include <cstdint>
@@ -82,9 +83,12 @@ namespace connect_code {
 
 
 	std::string encode(std::string address, std::string port) {
-		std::string addr_coded;
-		/* Convert the address to decimal, and convert that to hex */
+		std::string addr_coded = "";
 		if (check_ip_ver(address.data()) == 4) {
+			/* First, convert the address into a decimal format. Then convert this decimal format
+			into base-32, and also convert the port number into base-32. Join these together with
+			a "_". */
+			
 			/* I don't really have a reason to use my own function (dotted_dec_to_dec() 
 			and dec_to_dotted_dec()), to convert the IP address from text to binary.
 			The inet_pton() and inet_ntop() functions can do this just fine, and also
@@ -101,10 +105,9 @@ namespace connect_code {
 			Then, tokenize the string, using colons as the delimiters.
 			Finally, take each token in the string, and convert it from base-16 to base-32, appending a '-' as a delimiter. */
 			std::string addr_expanded = expand_ip6_addr(address);
-			std::string addr_coded = "";
 			std::vector<std::string> addr_tokenized = tokenize_str(addr_expanded, ":");
 			
-			for (int i = 0; i < addr_tokenized.size()-1; i++ ) {
+			for (size_t i = 0; i < addr_tokenized.size()-1; i++ ) {
 				addr_coded += base_convert(addr_tokenized[i], 16, 32);
 				addr_coded += "-";
 			}
@@ -113,9 +116,6 @@ namespace connect_code {
 			/* TODO - Check if the IP address is actually converted properly, and test if the server socket is created correctly.
 			 Also do the same for client side, and check client-server connection. */
 						
-			std::cout << addr_coded << std::endl;
-			abort();
-			
 		}
 		
 		/* Convert the port to hex */
@@ -127,32 +127,62 @@ namespace connect_code {
 	}
 
 	std::vector<std::string> decode(std::string connect_code) {
-		//<AIRPLANE_CODE>
+		if (connect_code.find("_") == std::string::npos) {
+			throw std::invalid_argument("Invalid code entered."); // There must be an underscore, to separate the address part from the port part
+		}
+		
 		int ip_ver = 0;
-		if (connect_code.find("-") == connect_code.npos) {
+		if (connect_code.find("-") != std::string::npos) {
 			ip_ver = 6; // If the string contains hyphens, it must be an IPv6 address encoding.
 		} else {
 			ip_ver = 4;
 		}
 		
-		//</AIRPLANE_CODE>
-		if (connect_code.find("_") == std::string::npos) {
-			throw std::invalid_argument("Invalid code entered.");
-		}
 		std::vector<std::string> result = tokenize_str(connect_code, "_"); /* Split the string into address and port */
-		std::string address = result[0]; /* Address (in base 16) */
-		std::string port = result[1]; /* Port (in base 16) */
+		std::string address = result[0]; /* Address (in base 32) */
+		std::string port = result[1]; /* Port (in base 32) */
+		
+		std::vector<std::string> ret_val;
+		
+		/* The IPv6 and IPv4 encodings are slightly different - I use a hyphen as a delimiter
+		for IPv6, while there is no delimiter for IPv4. This is why I need to check if the address
+		is IPv4 or IPv6. */
+		if (ip_ver == 4) {
+			/* Base 32 to base 10 - These lines convert the string to a base 10 number, and convert the result back into a string */
+			address = std::to_string(std::stoul(address, 0, 32));
+			port = std::to_string(std::stoul(port, 0, 32));
+
+			/* Convert decimal address to dotted decimal */
+			address = dec_to_dotted_dec(address);
+
+			/* Create a vector containing the address and the port, which will be returned */
+			ret_val.push_back(address);
+			ret_val.push_back(port);
+		} else {
+			/* IPv6 */
+			/* There are three main steps to decoding for IPv6:
+			1. Tokenize the address using the delimiter set while encoding ('-', in my case).
+			2. Convert each token from base-32 to base-16.
+			3. Join the string vector back together into a string, this time using ':' as a delimiter. This will give us our IP address. */
+
+			std::string conv_addr = ""; // Stores the final address
+			std::vector<std::string> address_tokenized = tokenize_str(address, "-"); // Step 1
+			
+			for (size_t i = 0; i < address_tokenized.size()-1; i++) {
+				address_tokenized[i] = base_convert(address_tokenized[i], 32, 16); // Step 2
+				conv_addr += address_tokenized[i] + ":"; // Step 3
+			}
+			conv_addr += base_convert(address_tokenized[address_tokenized.size()-1], 32, 16); // Add the last token
 
-		/* Base 16 to base 10 - These lines convert the string to a base 10 number, and convert the result back into a string */
-		address = std::to_string(std::stoul(address, 0, 32));
-		port = std::to_string(std::stoul(port, 0, 32));
+			port = std::to_string(std::stoul(port, 0, 32));
 
-		/* Convert decimal address to dotted decimal */
-		address = dec_to_dotted_dec(address);
+			std::cout << conv_addr << std::endl;
+			abort();
 
-		std::vector<std::string> ret_val;
-		ret_val.push_back(address);
-		ret_val.push_back(port);
+			ret_val.push_back(conv_addr);
+			ret_val.push_back(port);
+		}
+		
 		return ret_val;
 	}
 }