package com.atlassian.plugins.rest.sample.expansion.resource;
   
   import com.atlassian.plugins.rest.sample.expansion.entity.Player;
   import com.atlassian.plugins.rest.sample.expansion.entity.PlayerRecord;
   import com.atlassian.plugins.rest.sample.expansion.entity.Game;
   import com.atlassian.plugins.rest.sample.expansion.entity.Players;
   
   import javax.ws.rs.core.UriBuilder;
   import java.util.*;
  
  /**
   * Simulates a data storage layer.  It provides an interface to load the raw data and convert it in to the REST
   * level API objects.
   *
   * This datastore knows of two players, one of which has a record and one that doesn't.  Its intended to be used
   * by the {@link PlayerResource} to show an example on how to optionally show fields for expansion.
   */
  public class DataStore
  {
      private static final DataStore singleton = new DataStore();
  
      public static DataStore getInstance()
      {
          return singleton;
      }
  
      private Map<String, Game> games = new HashMap<String, Game>();
      private Map<Integer, String> playerNames = new TreeMap<Integer, String>();
      private Map<Integer, Integer> pointsScored = new HashMap<Integer, Integer>();
  
      private DataStore()
      {
          playerNames.put(0, "Adam Ashley-Cooper");
          playerNames.put(1, "Matt Giteau");
          playerNames.put(2, "Stephen Larkham");
          playerNames.put(3, "George Gregan");
          playerNames.put(4, "Mark Gerrard");
          playerNames.put(5, "George Smith");
          playerNames.put(6, "Stirling Mortlock");
          playerNames.put(7, "Clyde Rathbone");
          playerNames.put(8, "Jeremy Paul");
          playerNames.put(9, "Mark Chisholm");
          pointsScored.put(2, 513);
          games.put("rugby", new Game("Rugby"));
      }
  
      public Game getGame(String name, UriBuilder uriBuilder)
      {
          Game game = games.get(name);
          game.setPlayers(new Players(playerNames.size(), 5, uriBuilder));
          return game;
      }
  
      public List<Player> getPlayers(UriBuilder uriBuilder)
      {
          final List<Player> players = new ArrayList<Player>();
          for (Map.Entry<Integer, String> player : playerNames.entrySet())
          {
              players.add(new Player(player.getKey(), player.getValue(), uriBuilder));
          }
          return players;
      }
  
  
      public Player getPlayer(int id, UriBuilder builder)
      {
          Player player = new Player(id, playerNames.get(id), builder);
          if (playerHasRecord(id))
          {
              player.setRecord(PlayerRecord.emptyRecord(player));
          }
          return player;
      }
  
      public String getPlayerName(int id)
      {
          return playerNames.get(id);
      }
  
      /**
       * This simulates the use of a cheap call to a database to check the existence of potentially more expensive
       * data.  This is being used to detirmine if the client can see the expensive element at all and expand it.
       * @param id
       * @return
       */
      private boolean playerHasRecord(int id)
      {
          return pointsScored.containsKey(id);
      }
  
      /**
       * This simulates the lookup of the expensive data element about the given player.  In this case it simulates
       * the action of performing a query on a series of tables and calculating the total points scored by this player.
       * @param player
       * @return
       */
      public PlayerRecord getPlayerRecord(Player player)
      {
          return new PlayerRecord(pointsScored.get(player.getId()));
     }
 }