# frozen_string_literal: true

require 'pry-byebug'
require 'singleton'
require 'LittleWeasel'

require_relative 'keyboard_char'
require_relative 'keyboard_key'
require_relative 'keyboard_input'
require_relative 'keyboard_key_evaluator'

module MonkeyEngine
  class MonkeyKeyboardEnUs
    include Singleton

    attr_reader :keys, :left_keys, :right_keys

    def initialize
      LittleWeasel.configure do |config|
        config.max_dictionary_file_megabytes = 7
      end

      @keys = [
        # Row 1 of 5
        KeyboardKey.make_key('`', '~', :left, 1),
        KeyboardKey.make_key('1', '!', :left, 1),
        KeyboardKey.make_key('2', '@', :left, 1),
        KeyboardKey.make_key('3', '#', :left, 1),
        KeyboardKey.make_key('4', '$', :left, 1),
        KeyboardKey.make_key('5', '%', :left, 1),
        KeyboardKey.make_key('6', '^', :left, 1),
        KeyboardKey.make_key('7', '&', :right, 1),
        KeyboardKey.make_key('8', '*', :right, 1),
        KeyboardKey.make_key('9', '(', :right, 1),
        KeyboardKey.make_key('0', ')', :right, 1),
        KeyboardKey.make_key('-', '_', :right, 1),
        KeyboardKey.make_key('=', '+', :right, 1),
        KeyboardKey.make_key(:del, :del, :right, 1),

        # Row 2 of 5
        KeyboardKey.make_key(:tab, :tab, :left, 2),
        KeyboardKey.make_key('q', 'Q', :left, 1),
        KeyboardKey.make_key('w', 'W', :left, 1),
        KeyboardKey.make_key('e', 'E', :left, 1),
        KeyboardKey.make_key('r', 'R', :left, 1),
        KeyboardKey.make_key('t', 'T', :left, 1),
        KeyboardKey.make_key('y', 'Y', :left, 1),
        KeyboardKey.make_key('u', 'U', :right, 1),
        KeyboardKey.make_key('i', 'I', :right, 1),
        KeyboardKey.make_key('o', 'O', :right, 1),
        KeyboardKey.make_key('p', 'P', :right, 1),
        KeyboardKey.make_key('', '{', :right, 1),
        KeyboardKey.make_key('', '}', :right, 1),
        KeyboardKey.make_key('\\', '|', :right, 1),

        # Row 3 of 5
        KeyboardKey.make_key(:caps, :caps, :left, 3),
        KeyboardKey.make_key('a', 'A', :left, 1),
        KeyboardKey.make_key('s', 'S', :left, 1),
        KeyboardKey.make_key('d', 'D', :left, 1),
        KeyboardKey.make_key('f', 'F', :left, 1),
        KeyboardKey.make_key('g', 'G', :left, 1),
        KeyboardKey.make_key('h', 'H', :right, 1),
        KeyboardKey.make_key('j', 'J', :right, 1),
        KeyboardKey.make_key('k', 'K', :right, 1),
        KeyboardKey.make_key('l', 'L', :right, 1),
        KeyboardKey.make_key(';', ':', :right, 1),
        KeyboardKey.make_key('\'', '"', :right, 1),
        KeyboardKey.make_key(:enter, :enter, :right, 2),

        # Row 4 of 5
        KeyboardKey.make_key(:shift, :shift, :left, 5),
        KeyboardKey.make_key('z', 'Z', :left, 1),
        KeyboardKey.make_key('x', 'X', :left, 1),
        KeyboardKey.make_key('c', 'C', :left, 1),
        KeyboardKey.make_key('v', 'V', :left, 1),
        KeyboardKey.make_key('b', 'B', :left, 1),
        KeyboardKey.make_key('n', 'N', :right, 1),
        KeyboardKey.make_key('m', 'M', :right, 1),
        KeyboardKey.make_key(',', '<', :right, 1),
        KeyboardKey.make_key('.', '>', :right, 1),
        KeyboardKey.make_key('/', '?', :right, 1),
        KeyboardKey.make_key(:shift, :shift, :right, 5),

        # Row 5 of 5
        KeyboardKey.make_key(:space, :space, :left, 2),
        KeyboardKey.make_key(:space, :space, :right, 2)
      ]

      @left_keys = []
      @right_keys = []

      @keys.each do |key|
        # Separate the keys on the left side of the keyboard...
        if key.keyboard_key_section == :left
          key.keyboard_key_weight.times do
            left_keys.push(key)
          end
        end

        # Separate the keys on the right side of the keyboard...
        next unless key.keyboard_key_section == :right

        key.keyboard_key_weight.times do
          right_keys.push(key)
        end
      end

      @keys.freeze
      @keys_left.freeze
      @keys_right.freeze

      @en_us_dictionary = create_dictionary
    end

    def get_keyboard_input
      keyboard_input = KeyboardInput.new

      left_keys = @left_keys
      right_keys = @right_keys

      keys = left_keys.zip(right_keys).flatten.compact.shuffle

      keyboard_key_evaluator = KeyboardKeyEvaluator.new

      # Take the keys until we hit a key that terminates a word...
      keyboard_input.input = keys.take_while do |key|
        !keyboard_char_ends_word?(key.keyboard_char.char)
      end.filter_map { |key| keyboard_key_evaluator.get_char(key) }

      # Keep going until we get something...
      keyboard_input = get_keyboard_input if keyboard_input.input.empty?
      keyboard_input.is_word = en_us_dictionary.word_results(keyboard_input.input_to_s).success?

      keyboard_input
    end

    # Returns true if the character causes a word termination.
    def keyboard_char_ends_word?(char)
      [:tab, :enter, :space, '.'].include?(char)
    end

    private

    attr_accessor :en_us_dictionary

    def create_dictionary
      dictionary_manager = LittleWeasel::DictionaryManager.new
      en_us_key = LittleWeasel::DictionaryKey.new(language: :en, region: :us)
      en_us_dictionary = dictionary_manager.create_dictionary_from_file(
        dictionary_key: en_us_key, file: "dictionaries/#{en_us_key}.txt"
      )
      en_us_dictionary.add_preprocessors(word_preprocessors: [LittleWeasel::Preprocessors::EnUs::CapitalizePreprocessor.new])
      en_us_dictionary.add_filters(word_filters: [LittleWeasel::Filters::EnUs::SingleCharacterWordFilter.new])

      en_us_dictionary
    end
  end
end