/PlayerManager.java

/*

* Author: Shuyi Sun

* Student ID: 731209

* Date: 27th May, 2016

* Comment: Project C, TicTacToe game solution in COMP90041

* Description: this class contains all the Player instances

*              that will be recorded and methods to manipulate

*              the players.

*/

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.PrintWriter;

import java.util.Arrays;

import java.util.Scanner;

import java.util.StringTokenizer;



class PlayerManager{

	//the constant to store the file name

    public static final String DATA_FILE = "players.dat";



	//the String value of the player descent classes

    public static final String AIPLAYER_TYPE = "AIPlayer";

    public static final String HUMAN_PLAYER_TYPE = "HumanPlayer";



	//the constants represent the game result 

    public static final int WIN = 1;

    public static final int LOSE = 2;

    public static final int DRAW = 3;

	

	//this is a flag used to indicate that no player is found

    public static final Player NO_SUCH_PLAYER = null;

	

	//the maximum player number that this player manager can handle

    public static final int DEFAULT_PLAYER_CAPACITY = 100;

	

	//the initialized the player number of the player manager

    public static final int RESET_PLAYER_NUMBER = 0;

	

	//in remove and reset methods, the indicator for proceeded action

    public static final String

            CONFIRM_REMOVE_ALL = "Are you sure you want to remove all players? (y/n)";

    public static final String

            CONFIRM_RESET_ALL = "Are you sure you want to reset all player statistics? (y/n)";

			

	//confirmation reply of the program user			

    public static final String CONFIRM_ANSWER = "y";

	

	//error information when an error occurs

    public static final String

            USERNAME_EXISTS_ERROR = "The username has been used already.";

    public static final String

            PLAYER_NOT_EXISTS_ERROR = "The player does not exist.";

    public static final String

            FILE_ERROR = "Error opening file players.dat";



	//the player array and the total number of players

    private Player[] playerArray;

    private int playerTotalNum;



	//constructor for a default maximum player number, which is 100

    public PlayerManager(){

        this(DEFAULT_PLAYER_CAPACITY);

    }



	//constructor for a given maximum player number

	public PlayerManager(int totalPlayers){

        playerArray = new Player[totalPlayers];

        resetPlayerManager();

        resumePlayerStats();

    }



	//remove all the players in the array

    private void resetPlayerManager(){

        playerTotalNum = RESET_PLAYER_NUMBER;

    }



	//find a player given its userName, if not existent, return -1

    public Player getPlayer(String userName){

        String playerUserName;

        if(userName == null){

			//no username will be null

		    return NO_SUCH_PLAYER;

		}

        for(int i = 0; i < playerTotalNum; i++){

			//get the username of player i

            playerUserName = playerArray[i].getUserName();

            if(playerUserName.equals(userName)){

				//if the username is the same as the required one, return its index

                return playerArray[i];

			}

        }



		//if can not find the player, just return -1

        return NO_SUCH_PLAYER;

    }



	//add the given Player instance to the player list

    public void addPlayer(Player player){

		//if the player is null, do nothing

        if(player == null){

            return;

		}

		

        String playerUserName = player.getUserName();

        if(getPlayer(playerUserName) != NO_SUCH_PLAYER){

			//if the player already exists, print an error

            System.out.println(USERNAME_EXISTS_ERROR);

		}

        else{

			//if the player does not exist, add this player to the list

            playerArray[playerTotalNum] = player;

			

			//increment the total player number with one

            playerTotalNum++;

        }

    }



	//execute the remove command, remove a given player or remove all

    public void removePlayer(String userName){

        if(userName == null){

			//if no name given, ask if remove all the players

            System.out.println(CONFIRM_REMOVE_ALL);

            String answer = TicTacToe.scanner.nextLine();

			

            if(answer.equals(CONFIRM_ANSWER)){

				//remove all the players if user confirms

                removeAllPlayers();

			}

        }

        else{

			//if one name given, try to get the player instance first

            Player player = getPlayer(userName);

			

            if(player == NO_SUCH_PLAYER){

				//player does not exist, print error information

                System.out.println(PLAYER_NOT_EXISTS_ERROR);

			}

            else{

				//remove the specific player

			    removeOnePlayer(player);

			}

        }

    }



	//remove one player 

    private void removeOnePlayer(Player player){

        int playerNum ;



        //trying to find the player's index in the playerArray

        for(playerNum = 0; playerNum < playerTotalNum; playerNum++ ){

            if(player.equals(playerArray[playerNum]))

                break;

        }



        for(int i = playerNum; i < playerTotalNum - 1; i++){

			//move all the player one step forward to cover the removed player

            playerArray[i] = playerArray[i + 1];

		}

		

		//decrement the total player number with one

        playerTotalNum --;

    }



	//after confirmation, remove all the player in the array

    private void removeAllPlayers(){

		//reset the player manager to the initialized condition

        resetPlayerManager();

    }



	//edit one player with given family name and given name

    public void editPlayer(String userName, String familyName, String givenName){

		//trying to get the player instance first

        Player player = getPlayer(userName);

		

        if(player == NO_SUCH_PLAYER){

			//if no player found, print an error message

            System.out.println(PLAYER_NOT_EXISTS_ERROR);

		}

        else{

			//edit the players family name and given name

            player.setFamilyName(familyName);

            player.setGivenName(givenName);

        }

    }



	//reset the statistics of one or all players

    public void resetStats(String userName){

        if(userName == null){

			//ask the user if reset all players

            System.out.println(CONFIRM_RESET_ALL);

            String answer = TicTacToe.scanner.nextLine();

			

            if(answer.equals(CONFIRM_ANSWER)){

				//reset all player statistics after confirmation

                resetAllStats();

			}

        }

        else{

			//try get the player instance first

            Player player = getPlayer(userName);

            if( player == NO_SUCH_PLAYER){

				//if no player found, print an error message

                System.out.println(PLAYER_NOT_EXISTS_ERROR);

			}

            else{

				//reset statistics of specific player

                resetOneStats(player);

			}

        }

    }



	//reset statistics of all players

    private void resetAllStats(){

        for( int i = 0; i < playerTotalNum; i++ ){

			//reset every single player in this array

            resetOneStats(playerArray[i]);

		}

    }



    //reset the player statistics based on its index

    private void resetOneStats(Player player){

        //reset player statistics given its instance variable

        player.resetStats();

    }



	//display one or all player information with required format

    public void displayPlayer(String userName){

        if(userName == null){

			//if no username given, display all users

            displayAllPlayers();

        }

        else{

			//get the player instance first

            Player player = getPlayer(userName);

            if(player == NO_SUCH_PLAYER){

				//if no player found, print an error message

                System.out.println(PLAYER_NOT_EXISTS_ERROR);

			}

            else{

				//display the player according to its index in array

                displayOnePlayer(player);

			}

        }

    }



	//display all player information and statistics

    private void displayAllPlayers(){

		//create an array that contain all the players' usernames

        String[] userNames = new String[playerTotalNum];

		

        for(int i = 0; i < playerTotalNum; i++){

			//copy usernames of the array into the new String array

            userNames[i] = playerArray[i].getUserName();

		}

		

		//sort the array according to alphabetical sequence 

        Arrays.sort(userNames);

		

		//print out all the player information alphabetically

        for(int i = 0; i< playerTotalNum; i++){

			Player player = getPlayer(userNames[i]);

            displayOnePlayer(player);

		}

    }



    //display information and statistics of one player given the index

    private void displayOnePlayer(Player player){

        System.out.println(player.toString());

    }



	//display the ranking of all the players

    public void displayRankings(){

		//first print the headers

        System.out.println(" WIN  | DRAW | GAME | USERNAME");

		

		//sort the whole player array using defined comparison method

        Arrays.sort(playerArray, 0, playerTotalNum);

		

		//print out all the player game statistics

        for(int i = 0; i < playerTotalNum ; i++){

			//format the game statistics with required format

            formatResult(playerArray[i]);

		}

    }



	//format the game statistics of certain player

    private void formatResult(Player player){

		//print the winning ratio into XX% format 

        System.out.printf(" %3d", Math.round(player.getWinningRatio()*100));

        System.out.print("% | ");

		

		//print the drawn ratio into XX% format

        System.out.printf("%3d", Math.round(player.getDrawnRatio()*100));

        System.out.print("% | ");

		

		//print the number of game played into XX format

        System.out.printf("%2d", player.getNumberOfGamePlayed());

        System.out.print("   | ");

		

		//print the username and start a new line

        System.out.print(player.getUserName());

        System.out.println();

    }



	//when a game finishes, store the game result into the player instance respectively

    public void storeGameResult(Player player1, Player player2, int resultStats){

		//change to statistics of two players

        switch (resultStats){

            case WIN:

			    //player 1 wins player 2

                player1.win();

                player2.lose();

                break;

            case LOSE:

			    //player 2 wins player 1

                player1.lose();

                player2.win();

                break;

            case DRAW:

			    //the two players get drawn

                player1.draw();

                player2.draw();

                break;

            default:

        }

    }



	//this method restore all the information and statistics of players to a file

    public void recordPlayerStats(){

        PrintWriter outputStream = null;

		

        try{

			//try to open the file

            outputStream = new PrintWriter(new FileOutputStream(DATA_FILE));

        }

        catch (FileNotFoundException e){

			//if file cannot open, system terminates

            System.out.println(FILE_ERROR);

            System.exit(0);

        }



		//write the info and stats of every player to the local file

        for(int i = 0 ; i < playerTotalNum ; i++){

            outputStream.println(playerArray[i].getPlayerInfoStats());

        }



        outputStream.close();

    }



	//when system restart, import all the play info and stats into playManager

    private void resumePlayerStats(){

        Scanner inputStream = null;



        try{

			//try to open the file to write into

            inputStream = new Scanner(new FileInputStream(DATA_FILE));

        }

        catch (FileNotFoundException e){

			//if file cannnot open, give up resuming

            return ;

        }



		//import from file line by line

        while(inputStream.hasNextLine()){

			//parse the content of every line and add it to playerManager

            addPlayerFromRecord(inputStream.nextLine());

        }



        inputStream.close();

    }



	//add player to playerManager from the every single line

    private void addPlayerFromRecord(String record){

        StringTokenizer stOfRecord = new StringTokenizer(record);



		//get and split information from the String

        String userName = stOfRecord.nextToken();

        String familyName = stOfRecord.nextToken();

        String givenName = stOfRecord.nextToken();

        int numberOfGamePlayed = Integer.parseInt(stOfRecord.nextToken());

        int numberOfGameWon = Integer.parseInt(stOfRecord.nextToken());

        int numberOfGameDrawn = Integer.parseInt(stOfRecord.nextToken());

		

		//discard the "class" text

        stOfRecord.nextToken();

		

		//get the class type of the player

        String playerType = stOfRecord.nextToken();



        Player player = null;

		

        if(playerType.equals(AIPLAYER_TYPE)){

			//if the player is an aiplayer, load the information into an aiplayer class

            player = new AIPlayer(userName, familyName, givenName, 

			                numberOfGamePlayed, numberOfGameWon, numberOfGameDrawn);

        }

        else if(playerType.equals(HUMAN_PLAYER_TYPE)){

			//if the player is a human player, load the information into a humanplayer class

            player = new HumanPlayer(userName, familyName, givenName, 

			                numberOfGamePlayed, numberOfGameWon, numberOfGameDrawn);

        }

        else{

			//something wrong, system exit

            System.exit(-1);

        }



		//add this player to the player list

        addPlayer(player);

    }



}