Refactoring battleship game - ruby

Question

I'm creating a battleship game in Ruby.
Let me explain how it works:
The game is played on 5x5 grids (one per player).
Players have 2 ships each to place on their grid. A small ship (3x1 side) and a large one (4x1 size).
Players are asked in turn to place their ships on their board. A ship can't be placed out of bounds nor on the same space as another ship.
Players take turns to shoot at the opponent grid one after the other by selecting coordinates.
The first player to reach 7 points (all boats sinked) wins the game.
As you can see, some parts of my code are very repetitive:
I ask to each player to place its 2 ships so I have the "same" code 4 times (--- PLACEMENT OF THE SIZE 3 SHIP OF #{name_p1.upcase} ---).
I ask players to take turns to shoot at the opponent grid one after the other (this is done twice).
Same problem when I print the result of a shot.
I'm very struggling to refactor my code to make it simpler and shorter.
How can it be simplified?
# Board for player 1
board1 = []
for i in 0..4
board1[i] = []
(0..4).each do
board1[i].append('O')
end
end
# Board for player 2
board2 = []
for i in 0..4
board2[i] = []
(0..4).each do
board2[i].append('O')
end
end
# Display the boards
def display_board(board)
for row in board
puts row.map { |k| "#{k}" }.join(' ')
end
end
def check_obstacle(ship_size, player_array, posX, posY, direction)
check = 0
#ship_present = 0
#space_available = 0
#ship_present += 1 if player_array[posX][posY] == 1
#space_available += 1 if player_array[posX][posY] == 0
while check < ship_size && #space_available < ship_size
case direction
when 'north' then posX -= 1
when 'east' then posY += 1
when 'south' then posX += 1
when 'west' then posY -= 1
end
#space_available += 1 if posX.between?(0, 4) && posY.between?(0, 4)
#ship_present += 1 if posX.between?(0, 4) && posY.between?(0, 4) && player_array[posX][posY] == 1
check += 1
end
#space_available == ship_size && #ship_present == 0
end
def ship_placement(ship_size, player_array, posX, posY, direction)
steps = 0
while steps < ship_size && #ship_present == 0 && #space_available == ship_size
player_array[posX][posY] = 1
case direction
when 'north' then posX -= 1
when 'east' then posY += 1
when 'south' then posX += 1
when 'west' then posY -= 1
end
steps += 1
end
puts "The ship of size #{ship_size} is placed."
end
# Generation of the player boards
array1 = [[0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0]]
array2 = [[0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0]]
# A player wins when he/she reaches 7 points (2 ships each to place on their grid : a small ship (3x1 side) and a large one (4x1 size))
solution = 7
# We set the number of points at 0 at the start of the game
points_p1 = 0
points_p2 = 0
#Starting of the game and printing the board
while true do
puts 'Welcome soldiers!'
puts 'To start the game, enter "start". To quit, enter "stop":'
starting = gets.chomp
puts "\n"
case starting.downcase
when 'start'
puts 'Enter the first name of the first player:'
name_p1 = gets.chomp.to_s
puts "\n"
puts 'Enter the first name of the second player:'
name_p2 = gets.chomp.to_s
puts "\n"
puts "--- PLACEMENT OF THE SIZE 3 SHIP OF #{name_p1.upcase} ---"
while true
while true
puts 'Enter LINE number (between 1 and 5):'
placement_row = gets.chomp.to_i-1
break if placement_row.between?(0, 4)
end
while true
puts 'Enter COLUMN number (between 1 and 5):'
placement_column = gets.chomp.to_i-1
break if placement_column.between?(0, 4)
end
while true
puts "Enter ship direction (north, east, south ou west)"
orientation = gets.chomp.downcase
break if %w(north east south west).include? orientation
end
if check_obstacle(3, array1, placement_row, placement_column, orientation)
ship_placement(3, array1, placement_row, placement_column, orientation)
break
else
puts "Unable to place. Please try again."
end
end
puts "--- PLACEMENT OF THE SIZE 4 SHIP OF #{name_p1.upcase} ---"
while true
while true
puts 'Enter LINE number (between 1 and 5):'
placement_row = gets.chomp.to_i-1
break if placement_row.between?(0, 4)
end
while true
puts 'Enter COLUMN number (between 1 and 5):'
placement_column = gets.chomp.to_i-1
break if placement_column.between?(0, 4)
end
while true
puts "Enter ship direction (north, east, south ou west)"
orientation = gets.chomp.downcase
break if %w(north east south west).include? orientation
end
if check_obstacle(4, array1, placement_row, placement_column, orientation)
ship_placement(4, array1, placement_row, placement_column, orientation)
break
else
puts "Unable to place. Please try again."
end
end
###############################################################
puts "--- PLACEMENT OF THE SIZE 3 SHIP OF #{name_p2.upcase} ---"
while true
while true
puts 'Enter LINE number (between 1 and 5):'
placement_row = gets.chomp.to_i-1
break if placement_row.between?(0, 4)
end
while true
puts 'Enter COLUMN number (between 1 and 5):'
placement_column = gets.chomp.to_i-1
break if placement_column.between?(0, 4)
end
while true
puts "Enter ship direction (north, east, south ou west)"
orientation = gets.chomp.downcase
break if %w(north east south west).include? orientation
end
if check_obstacle(3, array2, placement_row, placement_column, orientation)
ship_placement(3, array2, placement_row, placement_column, orientation)
break
else
puts "Unable to place. Please try again."
end
end
puts "--- PLACEMENT OF THE SIZE 4 SHIP OF #{name_p2.upcase} ---"
while true
while true
puts 'Enter LINE number (between 1 and 5):'
placement_row = gets.chomp.to_i-1
break if placement_row.between?(0, 4)
end
while true
puts 'Enter COLUMN number (between 1 and 5):'
placement_column = gets.chomp.to_i-1
break if placement_column.between?(0, 4)
end
while true
puts "Enter ship direction (north, east, south ou west)"
orientation = gets.chomp.downcase
break if %w(north east south west).include? orientation
end
if check_obstacle(4, array2, placement_row, placement_column, orientation)
ship_placement(4, array2, placement_row, placement_column, orientation)
break
else
puts "Unable to place. Please try again."
end
end
while points_p1 < solution || points_p2 < solution
puts "--- #{name_p1.upcase}'S TURN ---"
while true
puts 'Enter LINE number (between 1 and 5):'
row_p1 = gets.chomp.to_i-1
break if row_p1.between?(0, 4)
end
while true
puts 'Enter COLUMN number (between 1 and 5):'
column_p1 = gets.chomp.to_i-1
break if column_p1.between?(0, 4)
end
# Shot fired!
case array1[row_p1][column_p1]
when 1
board1[row_p1][column_p1] = 'X'
array1[row_p1][column_p1] = 'X'
points_p1 += 1
when 0
board1[row_p1][column_p1] = '-'
array1[row_p1][column_p1] = '-'
when 'X', '-'
puts 'Square already played.'
next
end
puts "\n"
puts '--------------'
display_board(board1)
puts '--------------'
puts '----------------------'
puts "#{name_p1} has #{points_p1} point#{"s" if points_p1 > 1}."
puts '----------------------'
puts "\n"
break if points_p1 == solution
puts "--- #{name_p2.upcase}'S TURN ---"
while true
puts 'Enter LINE number (between 1 and 5):'
row_p2 = gets.chomp.to_i-1
break if row_p2.between?(0, 4)
end
while true
puts 'Enter COLUMN number (between 1 and 5):'
column_p2 = gets.chomp.to_i-1
break if column_p2.between?(0, 4)
end
# Shot fired!
case array2[row_p2][column_p2]
when 1
board2[row_p2][column_p2] = 'X'
array2[row_p1][column_p1] = 'X'
points_p2 += 1
when 0
board2[row_p2][column_p2] = '-'
when 'X', '-'
next
end
puts "\n"
puts '--------------'
display_board(board2)
puts '--------------'
puts '----------------------'
puts "#{name_p2} has #{points_p2} point#{"s" if points_p2 > 1}."
puts '----------------------'
puts "\n"
break if points_p2 == solution
end
puts "Congratulations #{name_p1}, you have destroyed all the enemy ships!" if points_p1 == solution
puts "Congratulations #{name_p2}, you have destroyed all the enemy ships!" if points_p2 == solution
puts "\n"
break
when 'stop'
puts 'See you soon!'
break
else
puts 'Please make a choice between "start". To exit, enter "stop".'
puts "\n"
end
end

Answer 1

As David mentions in his comment, you really want to make use of Ruby's object oriented features.
Here are some components I put together and some example usage. (Seemed like a fun exercise ... I guess I got carried away.)
class ShipPoint
attr_reader :row, :column, :owner
attr_accessor :hit
def initialize(row,column, owner)
#row = row
#column = column
#owner = owner
#hit = false
end
def to_s
#hit ? "X" : owner.label
end
end
class Ship
attr_reader :points, :name
attr_accessor :owner
def initialize(row:, column:, size:, direction:, name: nil, owner: nil)
#name = name
#owner = owner
case direction
when "north"
#points = (0...size).map { ShipPoint.new(row - _1, column, self) }
when "south"
#points = (0...size).map { ShipPoint.new(row + _1, column, self) }
when "east"
#points = (0...size).map { ShipPoint.new(row, column + _1, self) }
when "west"
#points = (0...size).map { ShipPoint.new(row, column - _1, self) }
end
end
def sunk?()
#points.all? {_1.hit}
end
def column_range()
Range.new(*#points.minmax_by {_1.column}.map {_1.column})
end
def row_range()
Range.new(*#points.minmax_by {_1.row}.map {_1.row})
end
def point(row,column)
#points.find {_1.row == row && _1.column == column}
end
def label()
return #name[0] if #name
owner.ships.index(self).to_s
end
end
class Board
attr_reader :range, :ships
def initialize(size=5)
#range = Range.new(0, size-1)
#content = Array.new(size) {Array.new(size)}
#ships = []
end
def add_ship(ship)
placeable = range.cover?(ship.column_range) && range.cover?(ship.row_range) && ship.points.all? {available?(_1.row, _1.column)}
if placeable
ship.owner = self
#ships << ship
ship.points.each {|p| #content[p.row][p.column] = ship}
else
puts "ship is unplaceable"
end
end
def to_s
display = ""
#content.each_index do |row|
row_display = ""
#content[row].each_index do |column|
location = #content[row][column]
row_display << (location ? location.point(row,column).to_s : ".")
end
display << "#{row_display}\n"
end
display
end
def available?(row, column)
#content[row][column].nil?
end
def target(row:,column:)
ship = #content[row][column]
point = ship&.point(row,column)
point&.hit = true
sunk = ship&.sunk?
all_sunk = #ships.all? {_1.sunk?}
case
when all_sunk then "all sunk"
when sunk then "Sunk: #{ship.name}"
when point&.hit then :hit
else :miss
end
end
end
b1 = Board.new
b2 = Board.new
s1 = Ship.new(row: 0, column: 1, size: 4, direction: "north")
s2 = Ship.new(row: 0, column: 1, size: 4, direction: "south", name: "Battle Ship")
s3 = Ship.new(row: 0, column: 1, size: 4, direction: "east")
s4 = Ship.new(row: 0, column: 1, size: 4, direction: "west")
s5 = Ship.new(row: 4, column: 0, size: 3, direction: "east")
b1.add_ship(s1)
b1.add_ship(s2)
b1.add_ship(s3)
b1.add_ship(s4)
b1.add_ship(s5)
puts b1
puts "result = #{b1.target(row: 0, column: 0)}"
puts "result = #{b1.target(row: 0, column: 1)}"
puts "result = #{b1.target(row: 1, column: 1)}"
puts "result = #{b1.target(row: 2, column: 1)}"
puts "result = #{b1.target(row: 3, column: 1)}"
puts "result = #{b1.target(row: 4, column: 0)}"
puts "result = #{b1.target(row: 4, column: 1)}"
puts "result = #{b1.target(row: 4, column: 2)}"
puts b1