GameInventory.java

/**
* @author Edvin Hellsing
* @version 1.0
*/

package foo; // Package named 'foo'.

import java.util.Scanner; // Import of scanner class from the Java API.
import java.io.*; // Import all the classes of io package.
import java.util.HashMap; // Import of Hashmap for storing information.
import java.util.LinkedHashMap; // Import of LinkedHashmap for storing information.
import java.util.*; // Import everything from java util.
import java.util.concurrent.atomic.*; // Import functions from atomic in java util.

/**
* GameInventory class has the hashmap which holds all items and its parameters, the method for add, read, update and delete items. It has the 'askString', 'askInt' and 'deleteInt' aswell.
*/
public class GameInventory {

   private LinkedHashMap<String, Item> gameInventory;

   /**
   * GameInventory constructor, new hashmap with string and item to hold items and its parameters.
   */
   public GameInventory() {
      this.gameInventory = new LinkedHashMap<String, Item>();

      // Two items from start
      /*Item item = new Item("JOWA", "king", 1993, Condition.MINT, true);
      this.gameInventory.put("JOWA", item);

      Item item1 = new Item("EDHE", "queen", 1893, Condition.POOR, false);
      this.gameInventory.put("EDHE", item1);*/
   }

   /**
   * addItem method to add items.
   */
   public void addItem() {
      System.out.println("So you want to add an item? Fill in the form below.");

      String name = askString("name");
      String desc = askString("description");
      int year = askInt("year (between 1000-2021)", 1000, 2021); // Take a look at this since you can add a year with just to digits today
      int intCond = askInt("condition (1 for New, 2 Mint, 3 for Good, 4 for Poor)", 1, 4);
      int intCurrentlyLoaned = askInt("loaned status (0 for No, 1 for Yes", 0, 1);

      Condition cond;
      switch (intCond) {
         case 1:
         cond = Condition.NEW;
         break;
         case 2:
         cond = Condition.MINT;
         break;
         case 3:
         cond = Condition.GOOD;
         break;
         case 4:
         cond = Condition.POOR;
         break;
         default:
         cond = Condition.POOR;
      }

      Boolean currentlyLoaned;
      if (intCurrentlyLoaned == 0) {
         currentlyLoaned = false;
      }
      else {
         currentlyLoaned = true;
      }

      System.out.println("The item '" + name + "' has been added.");

      this.gameInventory.put(name, new Item(name, desc, year, cond, currentlyLoaned));
   }

   /**
   * readItem method to read items.
   */
   public void readItem() {
      System.out.println("So you want to read about an item? Here's a list of all items that currently are saved in the database:");

      // Atomic to show all items in the database
      /* AtomicInteger i = new AtomicInteger(1);
      this.gameInventory.forEach((key, item) -> {
         int counter = i.getAndIncrement();
         System.out.println(counter + ". " + key);
      }); */

      // For each to show all items in the database
      int i = 1;
      for (Map.Entry<String, Item> entry : this.gameInventory.entrySet()) {
         System.out.println(i + ". " + entry.getKey());
         i++;
      }

      int size = this.gameInventory.size();
      if (size == 0) {
         System.out.println("No items have been saved.");
         return;
      }
   
      int number = askInt("number", 1, size);
      String name = "";

      int j = 1;
      for (Map.Entry<String, Item> entry : this.gameInventory.entrySet()) {
         if (j == number) {
            name = entry.getKey();
            break;
         }
         j++;
      }

      // Check if the entered name exsits in the hashmap, present information about it if it does.
      if (gameInventory.containsKey(name)) {
         Item item = this.gameInventory.get(name);
         System.out.println("Information about '" + name + "' presented below:");
         System.out.println("Item name: " + item.getName());
         System.out.println("Item description: " + item.getDesc());
         System.out.println("Item year: " + item.getYear());
         System.out.println("Item condition: " + item.getCond());
         System.out.println("Item currently loaned: " + item.getCurrentlyLoaned());
      }
      
      // If no information about the entered name, print this message.
      else {
         System.out.println("It seems like there's no information available about '" + name + "'. " + toMenuMessage);
      }
   }

   /**
   * updateItem method to update items.
   */
   public void updateItem() {
      System.out.println("So you want to update an item? When you're done, press S to save, or press Q to quit.");

      // System.out.println("Updating item");
      String name = askString("name");

      // Check if the entered name exsits in the hashmap, present information about it if it does.
      if (gameInventory.containsKey(name)) {
         Item item = this.gameInventory.get(name);
         
         String tempDesc = item.getDesc();
         int tempYear = item.getYear();
         Condition tempCond = item.getCond();
         boolean tempLoaned = item.getCurrentlyLoaned();

         boolean shouldLoop = true;

         while (shouldLoop) {
            System.out.println("Current information about '" + name + "' presented below:");
            System.out.println("1. Item description: " + tempDesc);
            System.out.println("2. Item year: " + tempYear);
            System.out.println("3. Item condition: " + tempCond);
            System.out.println("4. Item currently loaned: " + tempLoaned);
            
            String userChoice = askString("number between 1-4 to choose which information you want to update (it's not possible to change the item's name)");
            switch (userChoice) {
               case "1":
               tempDesc = askString("description");
               break;
               case "2":
               tempYear = askInt("year", 1000, 2021);
               break;
               case "3":
               int intCond = askInt("condition", 1, 4);
               switch (intCond) {
                  case 1:
                  tempCond = Condition.NEW;
                  break;
                  case 2:
                  tempCond = Condition.MINT;
                  break;
                  case 3:
                  tempCond = Condition.GOOD;
                  break;
                  case 4:
                  tempCond = Condition.POOR;
                  break;
                  default:
                  tempCond = Condition.POOR;
               }
               break;
               case "4":
               int i = askInt("loaned (0 for No, 1 for Yes", 0, 1);
               if (i == 0) {
                  tempLoaned = false;
               }
               else {
                  tempLoaned = true;
               }
               break;
               case "S":
               case "s":
               case "Save":
               case "save": {
                  item.setDesc(tempDesc);
                  item.setReleaseYear(tempYear);
                  item.setCond(tempCond);
                  item.setCurrentlyLoaned(tempLoaned);
                  shouldLoop = false;
                  System.out.println("The information has been saved.");
               }
               break;
               case "Q":
               case "q":
               case "Quit":
               case "quit": {
                  shouldLoop = false;
                  System.out.println("Update function has been quit. Any changes hasn't been saved.");
               }
               default:
               shouldLoop = false;
            }
         }
         System.out.println("Information about '" + name + "' presented below:");
         System.out.println("Item description: " + item.getDesc());
         System.out.println("Item year: " + item.getYear());
         System.out.println("Item condition: " + item.getCond());
         System.out.println("Item currently loaned: " + item.getCurrentlyLoaned());

         System.out.println(toMenuMessage);
      }
      // If no information about the entered name, print this message.
      else {
         System.out.println("It seems like there's no information available about '" + name + "'." + toMenuMessage);
      }
   }

   /**
   * deleteItem method to delete items.
   */
   public void deleteItem() {
      System.out.println("So you want to delete about an item?");

      // System.out.println("Deleting item");
      String name = askString("name");

      // Check if the entered name exsits in the hashmap, present information about it if it does.
      if (gameInventory.containsKey(name)) {
         Item item = this.gameInventory.get(name);
         System.out.println("The item '" + name + "' contains the informtaion below:");
         System.out.println("Item name: " + item.getName());
         System.out.println("Item description: " + item.getDesc());
         System.out.println("Item year: " + item.getYear());
         System.out.println("Item condition: " + item.getCond());
         System.out.println("Item currently loaned: " + item.getCurrentlyLoaned());

         // Double check if the user wants to remaove the entered item.
         int intDeleteItem = deleteInt("Do you like to delete '" + name + "' and all its information? Enter 0 for no, 1 for yes. (This action cannot be undone): ", 0, 1);

         // If not, print message.
         if (intDeleteItem == 0) {
            System.out.println("The item '" + name + "' wasn't deleted from your Retro Games Inventory.");
         }
            // If else (yes), delete item from hashmap, i.e. inventory and print message.
         else {
            gameInventory.remove(name);
            System.out.println("The item '" + name + "' has been deleted.");
         }
      }
      
      // If no information about the entered name, print this message.
      else {
         System.out.println("It seems like there's no item named '" + name + "'." + toMenuMessage);
      }
   }

   String toMenuMessage = "You'll be directed to the menu.";

   /**
   * askString method to  ask quesitions with strings as answer.
   * Create a Scanner object to read keyboard input regarding strings, and get the user's input. Input validation included.
   * @param what which is used to make the program a bit more flexible since it's possible to customize the string a bit where it's used.
   * @return str entered by user in upper cases (name, description, menu choice).
   * @exception e for Scanner, and a catch of exception.
   */
   private String askString(String what) {
      Scanner keyboard = new Scanner(System.in);
      String promtName = "Enter a " + what + " for the item: ";
      String invalidName = "You haven't entered a " + what + ". " + promtName;
      String str = "";
      try {
         System.out.print(promtName);
         str = keyboard.nextLine();
         while (str.length() < 1) {
            System.out.print(invalidName);
            str = keyboard.nextLine();
         }
      }
      catch(Exception e) {
         System.out.println(e);
         System.exit(0); //Have something else than system.exit?
      }

      if (what.equals("name")) {
         str = str.toUpperCase();
      }
      return str;
   }

   /**
   * askInt method to ask quesitions with integers as answer.
   * Create a Scanner object to read keyboard input regarding integers, and get the user's input. Input validation included.
   * @param what which is defined where it's used.
   * @param smallest to make the program a bit more flexible since it's possible to customize the values of the int 'smallest' where it's used.
   * @param largest to make the program a bit more flexible since it's possible to customize the values of the int 'largest' where it's used.
   * @return userInt entered by user (year, condition, loaned status).
   * @exception e for Scanner, and a catch of exception.
   */
   private int askInt(String what, int smallest, int largest) {
      Scanner keyboard = new Scanner(System.in);
      String prompt = "Enter a " + what + " for the item: ";
      String invalid = "You haven't entered a valid " + what + ". " + prompt;
      int userInt = 0;
      try {
         System.out.print(prompt);
         userInt = keyboard.nextInt();
         while (userInt < smallest || userInt > largest) {
            System.out.print(invalid);
            userInt = keyboard.nextInt();
         }
      }
      catch(Exception e) {
         System.out.println(e);
         System.exit(0);
      }
      return userInt;
   }

   /**
   * deleteInt method to ask validation quesitions with integers as answers before deleting items.
   * Create a Scanner object to read keyboard input regarding delete of integers, and get the user's input. Input validation included.
   * @param what which is defined where it's used.
   * @param smallest which is defined where it's used.
   * @param largest which is defined where it's used.
   * @return userInt entered in deleteInt (validation question when about to delete an item).
   * @exception e for Scanner, and a catch of exception.
   */
   private int deleteInt(String what, int smallest, int largest) {
      Scanner keyboard = new Scanner(System.in);
      String prompt = what;
      String invalid = "You haven't entered a valid choise, please do. " + prompt;
      int userInt = 0;
      try {
         System.out.print(prompt);
         userInt = keyboard.nextInt();
         while (userInt < smallest || userInt > largest) {
            System.out.print(invalid);
            userInt = keyboard.nextInt();
         }
      }
      catch(Exception e) {
         System.out.println(e);
         System.exit(0);
      }
      return userInt;
   }
}