Add the GameOfLife module API for generating universes and running them

2 files changed, 121 insertions, 3 deletions

diff --git a/CLI/ruby/lib/game_of_life.rb b/CLI/ruby/lib/game_of_life.rb
index 7f70933..f8eba24 100644
--- a/CLI/ruby/lib/game_of_life.rb
+++ b/CLI/ruby/lib/game_of_life.rb
@@ -1,11 +1,61 @@
 # frozen_string_literal: true
 
 require "game_of_life/version"
+require "game_of_life/plane"
 require "game_of_life/universe"
 require "game_of_life/cell"
 
+# Game of Life module entry point
 module GameOfLife
-  class Error < StandardError; end
+  class << self
+    # Generate a universe based on the options (from an input file/URI) or using a random/passed seed
+    # This method also sets the Classes/Modules constants for the run defining the options for
+    # Cell (Dead/Live) state representations, and the delay introduced after rendering each universe/generation
+    # and the banner for the info/options
+    #
+    # @param options [Hash] CLI options to generate initial conditions
+    # @option options [String | nil] "input" path to a local file or URL to open
+    # @option options [Numeric] "seed" number to use if no "input" is provided (defaults to random)
+    # @option options [Numeric] "width" of the universe
+    # @option options [Numeric] "height" of the universe
+    # @option options [Numeric] "delay" introduced after each cycle
+    # @option options [String] "live-cell" representation
+    # @option options [String] "dead-cell" representation
+    # @return [GameOfLife::Universe] populated with the parsed input/seed
+    def generate(options)
+      # Define the constants for Cell representation
+      GameOfLife::Cell.const_set(:LIVE_CELL, options["live-cell"])
+      GameOfLife::Cell.const_set(:DEAD_CELL, options["dead-cell"])
+      # Define the constant used for delay
+      GameOfLife.const_set(:DELAY, options["delay"].to_f)
+
+      banner = options["input"] ? "Input: #{options['input']}" : "Seed: #{options['seed']}"
+      # Define the constant used for banner info
+      GameOfLife.const_set(:BANNER, banner)
+
+      return GameOfLife::Generators::Input.new(options) if options["input"]
+      GameOfLife::Generators::Seed.new(options)
+    end
+
+    # The infinite running loop for rendering the current state of a universe
+    # and then evolving it and repeating.
+    def run(universe)
+      Kernel.loop do
+        GameOfLife.render(universe)
+        universe.evolve!
+      end
+    end
+
+    # Private method to do the terminal screen/scrollback buffer cleaning
+    # and rendering of the current universe/banner info
+    # based on the delay configured by the user
+    def render(universe)
+      puts "\33c\e[3J" # Clears the screen and scrollback buffer.
+      puts universe.to_s
+      puts BANNER
+      sleep(DELAY / 1000.0)
+    end
+  end
 
   # Generators module for generating the universe initial state
   module Generators
diff --git a/CLI/ruby/spec/game_of_life_spec.rb b/CLI/ruby/spec/game_of_life_spec.rb
index 5c93709..b4c1710 100644
--- a/CLI/ruby/spec/game_of_life_spec.rb
+++ b/CLI/ruby/spec/game_of_life_spec.rb
@@ -1,7 +1,75 @@
 # frozen_string_literal: true
 
 RSpec.describe GameOfLife do
-  it "has a version number" do
-    expect(GameOfLife::VERSION).not_to be nil
+  describe ".generate" do
+    let(:options) do
+      {
+        "live-cell" => "L",
+        "dead-cell" => "D",
+        "delay" => 100,
+        "width" => 10,
+        "height" => 20,
+        "seed" => 500,
+      }
+    end
+
+    context "with options['input']" do
+      before { options["input"] = "./file.txt" }
+
+      it "defines configurations constants" do
+        expect(described_class::Cell).to receive(:const_set).with(:LIVE_CELL, "L")
+        expect(described_class::Cell).to receive(:const_set).with(:DEAD_CELL, "D")
+        expect(described_class).to receive(:const_set).with(:DELAY, 100.0)
+        expect(described_class).to receive(:const_set).with(:BANNER, "Input: ./file.txt")
+
+        allow(described_class::Generators::Input).to receive(:new)
+        described_class.generate(options)
+      end
+
+      it "calls Generators::Input.new" do
+        allow(described_class::Cell).to receive(:const_set)
+        allow(described_class).to receive(:const_set)
+
+        expect(described_class::Generators::Input).to receive(:new).with(options)
+        described_class.generate(options)
+      end
+    end
+
+    context "without options['input']" do
+      before { options["seed"] = 1337 }
+
+      it "defines configurations constants" do
+        expect(described_class::Cell).to receive(:const_set).with(:LIVE_CELL, "L")
+        expect(described_class::Cell).to receive(:const_set).with(:DEAD_CELL, "D")
+        expect(described_class).to receive(:const_set).with(:DELAY, 100.0)
+        expect(described_class).to receive(:const_set).with(:BANNER, "Seed: 1337")
+
+        allow(described_class::Generators::Seed).to receive(:new)
+        described_class.generate(options)
+      end
+
+      it "calls Generators::Seed.new (and raises error)" do
+        allow(described_class::Cell).to receive(:const_set)
+        allow(described_class).to receive(:const_set)
+
+        expect { described_class.generate(options) }.to raise_error(NotImplementedError)
+      end
+    end
+  end
+
+  describe ".run" do
+    let(:universe) { GameOfLife::Universe.new(width: 3, height: 3) }
+
+    it "calls universe#evolve! and #{described_class}.run" do
+      # allow kernel loop tiwce
+      allow(Kernel).to receive(:loop).and_yield.and_yield
+
+      expect(described_class).to receive(:render).with(universe).twice
+      expect(universe).to receive(:evolve!).twice
+
+      described_class.run(universe)
+    end
   end
+
+  describe.pending ".render"
 end