The "Programming Problem": Chess Moves

Write an application that takes as input:
The name of a chess piece (King, Queen, Bishop, Knight, Rook, Pawn)
A starting digit, 0 to 9
As output the program should produce a list of all the legal phone numbers that can be generated by moving the piece around a standard phone pad, starting from the given digit. You should also supply the total number of different phone numbers that are produced for the case of a Queen starting on digit '5'.

A legal phone number has the following requirements:
Must be 10 digits long
Can contain only digits (no * or #)
The phone pad layout is:

  1 2 3
  4 5 6
  7 8 9
  * 0 #

But be careful, a legal move is defined as any move that would normally be legal for the piece in chess, with the following additions:
Staying in place is a legal move for all pieces
When a Pawn reaches the top row, it becomes a Queen
For the case where the piece is a Pawn, starting on one of the bottom two rows (i.e. any of the digits 7, 8, 9 and 0), the Pawn may move either one or two spaces forward, but only the first time it moves.

Installation

1) git clone git@github.com:Boltmade/Phonepad-Chess.git
2) cd Phonepad-Chess
3) bundle install
4) ruby main.rb