The games welcome screen and credits screen are also stored as text strings within the program file. Externalize the content of these two screens in separate text files named BJWelcome.txt and BJCredits.txt. Once these files have been created, remove the display_greeting and display_credits methods from the program file. Next, change the name of the get_help_file to get_file and modify the method so that it accepts an argu- ment named filename, representing the name of an external text file. Modify the method so that it retrieves and displays the con- tents of the text file passed to it as an argument. Next, modify the Main Script Logic section by replacing the statement that called on the get_help_file with a statement that calls on the get_file method. Make sure this new statement passes the full name and path of the text file to be displayed. Finally, replace the two statements that call on the display_greeting and display_credits methods with statements that call on the get_file method and pass it the name of the appropriate external text fil

# Define custom classes ---------------------------------------------------

#Define a class representing the console window

class Screen

def cls #Define a method that clears the display area

puts (" " * 25) #Scroll the screen 25 times

puts "\a" #Make a little noise to get the player's attention

end

def pause #Define a method that pauses the display area

STDIN.gets #Execute the STDIN class's gets method to pause script

#execution until the player presses the enter key

end

end

#Define a class representing the Ruby Blackjack game

class Game

#This method displays the game's opening message

def display_greeting

Console_Screen.cls #Clear the display area

#Display a welcome message

print "\t\t\tWelcome to the Ruby Blackjack Game!" +

" Press Enter to " +

"continue. "

Console_Screen.pause #Pause the game

end

#Define a method to be used to display game instructions

def display_instructions

Console_Screen.cls #Clear the display area

puts "INSTRUCTIONS: " #Display a heading

#Display the game's instructions

puts "This game is based on the Blackjack card game, where the"

puts "objective is to beat the dealer by acquiring cards that total"

puts "higher than the dealer's cards without going over 21. In this"

puts "version, the player and dealer are each dealt an initial card. The"

puts "player is then prompted to draw additional cards. The player"

puts "may draw as many additional cards as desired, as long as the"

puts "player's hand adds up to less than 21. If the player's hand goes"

puts "over 21, the player busts and the dealer automatically"

puts "wins. Once the player decides to hold, it is the dealer's"

puts "turn. The dealer continues to add new cards to his hand"

puts "until it adds up to 17 or more or the dealer busts. Once the"

puts "dealer's hand is complete, the game analyzes the player's hand"

puts "and the dealer's hand to determine the results of the game."

puts " "

print "Press Enter to continue. "

Console_Screen.pause #Pause the game

end

#Define a method to control game play

def play_game

Console_Screen.cls #Clear the display area

#Assist the player and dealer an initial starting card

playerHand = get_new_card

dealerHand = get_new_card

#Call the method responsible for dealing new cards to the player

playerHand = complete_player_hand(playerHand, dealerHand)

#If the player has not gone bust, call the method responsible for managing

#dealer's hand

if playerHand <= 21 then

dealerHand = play_dealer_hand(dealerHand)

end

#call the method responsible for determining the results of the game

determine_winner(playerHand, dealerHand)

end

#Define a method responsible for dealing a new card

def get_new_card

#Assign a random number between 1 and 13 as the value of the card being

#created

card = 1 + rand(13)

#A value of 1 is an ace, so reassign the card a value of 11

return 11 if card == 1

#A value of 10 or more equals a face card so reassign the card a value

#of 10

return 10 if card >= 10

return card #Return the value assigned to the new card

end

#Define a method responsible for dealing the rest of the player's hand

def complete_player_hand(playerHand, dealerHand)

loop do #Loop forever

Console_Screen.cls #Clear the display area

#Show the current state of the player and dealer's hands

puts "Player's hand: " + playerHand.to_s + " "

puts "Dealer's hand: " + dealerHand.to_s + " "

print "Would you like another card? (Y/N) "

reply = STDIN.gets #Collect the player's answer

reply.chop! #Remove any extra characters appended to the string

#See if the player decided to ask for another card

if reply =~ /y/i then

#Call method responsible for getting a new card and add it to the

#player's hand

playerHand = playerHand + get_new_card

end

#See if the player has decided to stick with the current hand

if reply =~ /n/i then

break #Terminate the execution of the loop

end

if playerHand > 21 then

break #Terminate the execution of the loop

end

end

#Return the value of the player's hand

return playerHand

end

#Define a method responsible for managing the dealer's hand

def play_dealer_hand(dealerHand)

loop do #Loop forever

#If the value of the dealer's hand is less than 17 then give the

#dealer another card

if dealerHand < 17 then

#Call method responsible for getting a new card and add it to the

#dealer's hand

dealerHand = dealerHand + get_new_card

else

break #Terminate the execution of the loop

end

end

#Return the value of the dealer's hand

return dealerHand

end

#Define a method responsible for analyzing the player and dealer's

#hands and determining who won

def determine_winner(playerHand, dealerHand)

Console_Screen.cls #Clear the display area

#Show the value of the player and dealer's hands

puts "Player's hand: " + playerHand.to_s + " "

puts "Dealer's hand: " + dealerHand.to_s + " "

if playerHand > 21 then #See if the player has gone bust

puts "You have gone bust! "

print "Press Enter to continue."

else #See if the player and dealer have tied

if playerHand == dealerHand then

puts "Tie! "

print "Press Enter to continue."

end

#Dee if the dealer has gone bust

if dealerHand > 21 then

puts "The Dealer has gone bust! "

print "Press Enter to continue."

else

#See if the player's hand beats the dealer's hand

if playerHand > dealerHand then

puts "You have won! "

print "Press Enter to continue."

end

#See if the dealer's hand beats the player's hand

if playerHand < dealerHand then

puts "The Dealer has won! "

print "Press Enter to continue."

end

end

end

Console_Screen.pause #Pause the game

end

#This method displays information about the Ruby Blackjack game

def display_credits

Console_Screen.cls #Clear the display area

#Thank the player and display game information

puts "\t\t Thank you for playing the Ruby Blackjack game. "

puts " \t\t\t Developed by Jerry Lee Ford, Jr. "

puts "\t\t\t\t Copyright 2010 "

puts "\t\t\tURL: http://www.tech-publishing.com "

end

end

# Main Script Logic -------------------------------------------------------

Console_Screen = Screen.new #Instantiate a new Screen object

BJ = Game.new #Instantiate a new Game object

#Execute the Game class's display_greeting method

BJ.display_greeting

answer = "" #Initialize variable and assign it an empty string

#Loop until the player enters y or n and do not accept any other input

loop do

Console_Screen.cls #Clear the display area

#Prompt the player for permission to start the game

print "Are you ready to play Ruby Blackjack? (y/n): "

answer = STDIN.gets #Collect the player's answer

answer.chop! #Remove any extra characters appended to the string

#Terminate the loop if valid input was provided

break if answer =~ /y|n/i

end

#Analyze the player's answer

if answer =~ /n/i #See if the player wants to quit

Console_Screen.cls #Clear the display area

#Invite the player to return and play the game some other time

puts "Okay, perhaps another time. "

else #The player wants to play the game

#Execute the game class's display_instructions method

BJ.display_instructions

playAgain = "" #Initialize variable and assign it an empty string

loop do #Loop forever

#Execute the Game class's play_game method

BJ.play_game

loop do #Loop forever

Console_Screen.cls #Clear the display area

#Find out if the player wants to play another round

print "Would you like to play another hand? (y/n): "

playAgain = STDIN.gets #Collect the player's response

playAgain.chop! #Remove any extra characters appended to the string

#Terminate the loop if valid input was provided

break if playAgain =~ /n|y/i

end

#Terminate the loop if valid input was provided

break if playAgain =~ /n/i

end

#Call upon the Game class's display_credits method

BJ.display_credits

end