Merge branch 'master' of https://gitlab.tugraz.at/coding_tug/coding-streams

2021-oop1/ku/stream-05-19-2021/input_parsing.cpp

+#include <iostream>
+#include <algorithm>
+
+// VALID COMMANDS:
+// "quit"
+// "set x"
+
+
+enum Command {QUIT, SET };
+
+std::string readInput()
+{
+  std::string input_string;
+  std::cout << "> ";
+  std::getline(std::cin, input_string);
+  if(input_string.length() > 10)
+    throw std::length_error("[ERROR] Input too long");
+  if(input_string.length() < 4)
+    throw std::length_error("[ERROR] Input too short");
+
+  std::transform(input_string.begin(), input_string.end(), input_string.begin(),[](unsigned char c){ return std::tolower(c); });
+  return input_string;
+}
+
+size_t validateAndGetNrOfWords(std::string& input)
+{
+  size_t nr_of_words = std::count(input.cbegin(), input.cend(), ' ') + 1;
+  if(nr_of_words != 1 && nr_of_words != 2)
+    throw std::out_of_range("[ERROR] too many words");
+  return nr_of_words;
+}
+
+Command getValidCommand(std::string& input)
+{
+  size_t nr_of_words = validateAndGetNrOfWords(input);
+  if(nr_of_words == 1)
+  {
+    if(input == "quit")
+      return Command::QUIT;
+    else
+      throw std::invalid_argument("[ERROR] invalid command with one word");
+  }
+  else
+  {
+    if(input == "set x")
+      return Command::SET;
+    else
+      throw std::invalid_argument("[ERROR] invalid command with two words");
+  }
+}
+
+Command getCommand()
+{
+  while(true)
+  {
+    try
+    {
+      std::string input = readInput();
+      Command current_command = getValidCommand(input);
+      return current_command;
+    }
+    catch(std::length_error& e)
+    {
+      std::cout << e.what() << std::endl;
+    }
+    catch(std::out_of_range& e)
+    {
+      std::cout << e.what() << std::endl;
+    }
+    catch(std::invalid_argument& e)
+    {
+      std::cout << e.what() << std::endl;
+    }
+  }
+}
+
+
+int main()
+{
+  std::cout << "Insane OOP Game - enter set x or quit" << std::endl;
+  Command current_command = SET;
+  while(current_command != QUIT)
+  {
+  current_command = getCommand();
+  std::cout << (current_command == SET ? "SET X COMMAND" : "QUIT COMMAND") << std::endl;
+  }
+
+  return 0;
+}