Aruuz StateMachine Implementation

state_machine_class.rb

module Aruuz
  class StateMachine
    TRANSITIONS = {
      "hindi": {
        "-": [2, 4, -1, 0, 5, -1, 7, -1],
        "=": [1, 0, 3, -1, 6, 1, -1, 0]
      },
      "zamzama": {
        "-": [1, 2, -1, -1],
        "=": [3, -1, 0, 0]
      },
      "orig_hindi": {
        "-": [-1, 2, 3, -1],
        "=": [1, 0, -1, 1]
      }
    }

    def self.next_state meter, input, cur_state
      return -1 if cur_state < 0
      TRANSITIONS[meter][input][cur_state] || -1
    end
  end
end

# This is how it will be accessed
Aruuz::StateMachine.next_state "hindi", "-", 1
# => 4

state_machine_instance.rb

module Aruuz
  class StateMachine
    attr_reader :state
    @@transitions = {
      "hindi": {
        "-": [2, 4, -1, 0, 5, -1, 7, -1],
        "=": [1, 0, 3, -1, 6, 1, -1, 0]
      },
      "zamzama": {
        "-": [1, 2, -1, -1],
        "=": [3, -1, 0, 0]
      },
      "orig_hindi": {
        "-": [-1, 2, 3, -1],
        "=": [1, 0, -1, 1]
      }
    }

    def initialize meter
      @trans = @@transitions[meter]
      @state = 0
    end

    def next_state input
      @state = @trans[input][@state] || -1 unless @state < 0
    end
  end
end

# This is how it will be accessed
sm = Aruuz::StateMachine.new "hindi"
# => 0
sm.state
# => 0
sm.next_state "-"
# => 2
sm.state
# => 2