lib/cli: Add usage generator.

src/lib/cli.cpp

@@ -258,5 +258,54 @@ namespace CLI {
         // argument is not present, but this is not an error -> false, NOT_PRESENT, ""
         else return ErrorOr<std::string>(false, ErrorCodes::NOT_PRESENT, std::string(""));
     }
-    //std::string ArgumentsParser::getUsage();
+
+    std::string ArgumentsParser::getUsage(){
+        std::string usageString = "Help: " + this->programName + "\n\n\t" + this->description + "\n\n" + "Usage: " + this->programName;
+        
+        if(!this->flagsByShortName.empty()){
+            usageString += " [-";
+        }
+
+        for(const auto& [key, value]: this->flagsByShortName){
+            usageString.push_back(key);
+        }
+
+        if(!this->flagsByShortName.empty()){
+            usageString += "] ";
+        } 
+
+        for(const auto& [key, value]: this->optionsByShortName){
+            usageString += "[-";
+            usageString.push_back(key);
+            usageString += " " + value->placeholder + "] ";
+        }
+
+        for(const auto& argument: this->arguments){
+            usageString += argument.placeholder + " ";
+        }
+
+        usageString += "\n\nFlags:\n";
+
+        for(const auto& [key, value]: this->flagsByShortName){
+            usageString += "\t-";
+            usageString.push_back(key);
+            usageString += ", --" + value->longName + "\n\t\t" + value->description + "\n";
+        }
+
+        usageString += "\nOptions:\n";
+
+        for(const auto& [key, value]: this->optionsByShortName){
+            usageString += "\t-";
+            usageString.push_back(key);
+            usageString += " " + value->placeholder + ", --" + value->longName + "=" + value->placeholder + "\n\t\t" + value->description + "\n";
+        }
+
+        usageString += "\nArguments:\n";
+
+        for(const auto& argument: this->arguments){
+            usageString += "\t" + argument.placeholder + "\n\t\t" + argument.description + "\n";
+        }
+
+        return usageString;
+    }
 }

src/test/cli_argument_parser.cpp

@@ -636,5 +636,25 @@ int main() {
     delete[] tooManyArgumentsTestParameterList;
     std::cout << "Passed too many arguments test." << std::endl;
 
+    std::vector<CLI::Flag> helpTestFlags;
+    helpTestFlags.push_back(CLI::Flag('a', "apple", "throws an apple on Newton's head."));
+    helpTestFlags.push_back(CLI::Flag('y', "yapple", "throws an yapple on Newton's head."));
+
+    std::vector<CLI::Option> helpTestOptions;
+    helpTestOptions.push_back(CLI::Option('b', "banana", "BANANA", "smack someone with a ripe banana."));
+    helpTestOptions.push_back(CLI::Option('c', "corn", "CORNHUBBBBB", "visit cornhub."));
+
+    std::vector<CLI::Argument> helpTestArguments;
+    helpTestArguments.push_back(CLI::Argument("WASH", "Number of times to wash my shark."));
+    helpTestArguments.push_back(CLI::Argument("SHAKE", "Number of times to shake fist at cloud."));
+
+    const char** helpTestCommand = new const char*[1];
+    helpTestCommand[0] = "universecreator";
+    CLI::ArgumentsParser helpTestParser = CLI::ArgumentsParser(1, helpTestCommand, helpTestFlags, helpTestOptions, helpTestArguments, "Create a universe with a banana and an apple.");
+
+    ASSERT(helpTestParser.getUsage() == "Help: universecreator\n\n\tCreate a universe with a banana and an apple.\n\nUsage: universecreator [-ay] [-b BANANA] [-c CORNHUBBBBB] WASH SHAKE \n\nFlags:\n\t-a, --apple\n\t\tthrows an apple on Newton's head.\n\t-y, --yapple\n\t\tthrows an yapple on Newton's head.\n\nOptions:\n\t-b BANANA, --banana=BANANA\n\t\tsmack someone with a ripe banana.\n\t-c CORNHUBBBBB, --corn=CORNHUBBBBB\n\t\tvisit cornhub.\n\nArguments:\n\tWASH\n\t\tNumber of times to wash my shark.\n\tSHAKE\n\t\tNumber of times to shake fist at cloud.\n");
+    std::cout << "Passed Argument Parser usage test." << std::endl;
+    
+
     return 0;
 }

src/tools/hexnet.cpp

@@ -165,7 +165,7 @@ int main(int argc, char* argv[]){
     std::vector<CLI::Argument> arguments;
     arguments.push_back(CLI::Argument("PORT", "the port to use"));
 
-    CLI::ArgumentsParser cliParser = CLI::ArgumentsParser(argc, argv, flags, options, arguments);
+    CLI::ArgumentsParser cliParser = CLI::ArgumentsParser(argc, argv, flags, options, arguments, "Arbitrary tcp/udp connections in hex format.");
 
     if (cliParser.wrongUsage) {
         //TODO: spit out usage information generated by the parser