Script that converts iTerm themes to Alacritty

iterm_theme_to_alacritty.rb

#!/usr/bin/env ruby
# frozen_string_literal: true

# USAGE:
# curl https://gist.github.com/stankec/.../iterm_theme_to_alacritty.rb > iterm_theme_to_alacritty.rb
# chmod +x iterm_theme_to_alacritty.rb
# ./iterm_theme_to_alacritty.rb path/to/your/theme.itermcolors
#
# This will output the config to the terminal
#
# NOT RECOMENDED, but you can also write to the config by passing 'write' as the
# second argument.
# E.g:
# ./iterm_theme_to_alacritty.rb path/to/your/theme.itermcolors write

require 'rubygems'
require 'bundler'
require 'yaml'

# Install dependencies
begin
  require 'plist'
rescue LoadError
  # gemfile <<-G
  #   source "https://rubygems.org"
  #   gem "plist"
  # G

  # bundle 'install --deployment'

  # retry
  puts 'Run `gem install plist` first'
  exit(1)
end

LOOKUP_PATHS = [
  "#{Dir.home}/.config/alacritty/alacritty.yml"
].freeze

def write?
  ARGV[1] == 'write'
end

existing_configs = LOOKUP_PATHS.select { |path| File.exist?(path) }
config_path = existing_configs.first

if write? && config_path.nil?
  puts 'No Alacritty config found!'
  exit(1)
end

iterm2_theme_path = ARGV[0] || ''

unless File.exist?(iterm2_theme_path)
  puts "iTerm2 theme not found! Searched '#{iterm2_theme_path}'"
  exit(1)
end

begin
  theme = Plist.parse_xml(iterm2_theme_path)
rescue
  puts "'#{iterm2_theme_path}' is not a validiTerm2 theme!"
  exit(1)
end

class Theme
  class Color
    attr_accessor :color

    def initialize(color)
      @color = color
    end

    def red
      color['Red Component'].to_f
    end

    def green
      color['Green Component'].to_f
    end

    def blue
      color['Blue Component'].to_f
    end

    def formatted_hex
      "0x#{hex}"
    end

    def hex
      [
        hex_component(red),
        hex_component(green),
        hex_component(blue)
      ].join('')
    end

    def hex_component(float)
      (float * 255).to_i.clamp(0, 255).to_s(16)
    end
  end

  attr_accessor :theme

  def initialize(theme)
    @theme = theme
  end

  def ansi_color(i)
    color("Ansi #{i} Color")
  end

  def background
    color('Background Color')
  end

  def foreground
    color('Foreground Color')
  end

  def cursor_text
    color('Cursor Text Color')
  end

  def cursor
    color('Cursor Color')
  end

  private

  def color(key)
    to_color(theme[key])
  end

  def to_color(color)
    return unless color
    Color.new(color)
  end
end

theme = Theme.new(theme)

begin
  config = (write? && YAML.load_file(config_path)) || {}
rescue
  puts 'Invalid Alacritty config format!'
  exit(1)
end

colors = {
  primary: {
    background: theme.background.formatted_hex,
    foreground: theme.foreground.formatted_hex
  },
  cursor: {
    text: theme.cursor_text.formatted_hex,
    cursor: theme.cursor.formatted_hex
  },
  normal: {
    black: theme.ansi_color(0).formatted_hex,
    red: theme.ansi_color(1).formatted_hex,
    green: theme.ansi_color(2).formatted_hex,
    yellow: theme.ansi_color(3).formatted_hex,
    blue: theme.ansi_color(4).formatted_hex,
    magenta: theme.ansi_color(5).formatted_hex,
    cyan: theme.ansi_color(6).formatted_hex,
    white: theme.ansi_color(7).formatted_hex
  },
  bright: {
    black: theme.ansi_color(8).formatted_hex,
    red: theme.ansi_color(9).formatted_hex,
    green: theme.ansi_color(10).formatted_hex,
    yellow: theme.ansi_color(11).formatted_hex,
    blue: theme.ansi_color(12).formatted_hex,
    magenta: theme.ansi_color(13).formatted_hex,
    cyan: theme.ansi_color(14).formatted_hex,
    white: theme.ansi_color(15).formatted_hex
  }
}

def stringify_keys(hash)
  case hash
  when Array then hash.map { |e| stringify_keys(e) }
  when Hash then Hash[hash.map { |k, v| [k.to_s, stringify_keys(v)] }]
  else hash
  end
end

config['colors'] = stringify_keys(colors)

def write_config(cfg)
  File.open(config_path, 'w') do |f|
    f.write(cfg.to_yaml)
  end
rescue
  puts 'Unable to write Alacritty config!'
  exit(1)
end

def print_config(cfg)
  puts cfg.to_yaml
end

case ARGV[1]
when 'write' then write_config(config)
when nil then print_config(config)
end

puts 'Done!'