Retrieve and process an icon for a local or App Store app

grabicon.rb

#!/usr/bin/env ruby -W1
# frozen_string_literal: true

# Mac only
#
# Usage: grabicon.rb SEARCH TERMS [%[small|medium|large] [@[mac|ios|iphone|ipad]]
# If the search terms match a local app, that app's icon will be extracted and converted to PNG
# If the search terms don't match a local app, iTunes will be searched
# If the search terms end with "mac", "iphone", "ipad", or "ios", iTunes will be searched for a match
#
# If an iOS app is retrieved from iTunes, its corners will be automatically rounded and padding will be
# added to the resulting image.
#
# Requires that ImageMagick be installed (brew install imagemagick)

%w[net/http cgi json fileutils optparse].each do |filename|
  require filename
end

# Size of icon
DEFAULT_SIZE = 512

# Icon retrieval
class GrabIcon
  attr_reader :icon

  def initialize(terms)
    @terms = terms
    @icon = if terms =~ /@(ios|ipad|iphone)\b/i
              find_itunes_icon
            else
              appdir = find_app_dir
              if appdir
                retrieve_local_icon(appdir)
              else
                find_itunes_icon
              end
            end
  end

  def appdirs
    [
      '/System/Applications/',
      '/Developer/Applications/',
      '/Developer/Applications/Utilities/',
      '/Applications/Utilities/',
      '/Applications/Setapp/',
      '/Applications/'
    ]
  end

  def find_app_dir
    appdir = nil
    app = @terms.gsub(/ *(@(mac|i(os|phone|pad))|%(s(m(all)?)?|m(ed(ium)?)?|l(g|arge)?|\d+))/, '').gsub(/\s+/, ' ').strip
    appdirs.filter do |dir|
      if File.exist?(File.join(dir, "#{app}.app"))
        appdir = dir
      elsif File.exist?(File.join(dir, "#{app}.localized/#{app}.app"))
        appdir = File.join(dir, "#{app}.localized/")
      end
    end
    appdir
  end

  def size
    case @terms
    when /%l/
      512
    when /%m/
      256
    when /%s/
      128
    when /%(\d+)/
      Regexp.last_match(1).to_i
    else
      DEFAULT_SIZE
    end
  end

  def retrieve_local_icon(appdir)
    app = @terms.gsub(/ *(@(mac|i(os|phone|pad))|%(s(m(all)?)?|m(ed(ium)?)?|l(g|arge)?|\d+))/, '').gsub(/\s+/, ' ').strip
    icon = `defaults read "#{appdir}#{app}.app/Contents/Info" CFBundleIconFile`.strip.sub(/\.icns$/, '')

    outfile = File.join(File.expand_path('~/Desktop'), "#{app}_icon.png")
    cmd = [
      "/usr/bin/sips -s format png --resampleHeightWidthMax #{size}",
      %("#{File.join(appdir, "#{app}.app", "Contents/Resources/#{icon}.icns")}"),
      %(--out "#{outfile}")
    ]
    `#{cmd.join(' ')}`
    warn "Wrote PNG to #{outfile}."
    outfile
  end

  def define_entity
    case @terms
    when /\biphone\b/i
      'software'
    when /\bmac\b/i
      'macSoftware'
    else
      'iPadSoftware'
    end
  end

  def find_itunes_icon
    @entity = define_entity
    search = @terms.gsub(/ *(@(mac|i(os|phone|pad))|%(s(m(all)?)?|m(ed(ium)?)?|l(g|arge)?|\d+))/, '').gsub(/\s+/, ' ').strip
    url = "http://itunes.apple.com/search?term=#{CGI.escape(search)}&entity=#{@entity}"
    pp url
    res = Net::HTTP.get_response(URI.parse(url)).body
    begin
      json = JSON.parse(res)
      pp json
      icon_url = json['results'][0]['artworkUrl512']
      retrieve_itunes_icon(icon_url, search)
    rescue StandardError
      raise 'Invalid JSON returned'
    end
  end

  def retrieve_itunes_icon(icon_url, app)
    url = URI.parse(icon_url)
    filename = "#{app.gsub(/[^a-z0-9]+/i, '-')}.#{icon_url.match(/\.(jpg|png)$/)[1]}"
    outfile = File.join(File.expand_path('~/Desktop'), filename)

    res = Net::HTTP.get_response(url)
    File.open(outfile, 'w+') { |f| f.puts res.body }
    warn "Wrote iTunes search result to #{outfile}."
    process_ios_image(outfile, DEFAULT_SIZE) unless @entity == 'macSoftware'
    outfile
  rescue StandardError
    raise 'Failed to write icon from iTunes search.'
  end

  def round_corners(filename, size, round = 0.2)
    round = (size * round).round.to_s
    target = filename.sub(/\.\w+$/, '_round.png')
    cmd = [
      "convert -size #{size}x#{size} xc:none -fill white -draw 'roundRectangle 0,0 #{size},#{size} #{round},#{round}'",
      filename,
      '-compose SrcIn -composite',
      target
    ]
    `#{cmd.join(' ')} &> /dev/null`
    target
  end

  def process_ios_image(filename, size = 512)
    target = round_corners(filename, size, 0.205)
    reduced = size - (size * 0.10)
    reduced_rect = "#{reduced}x#{reduced}"

    `convert -bordercolor 'rgba(0,0,0,0)' -border 50x50 -resize #{reduced_rect} #{target} #{target} &> /dev/null`

    FileUtils.rm(filename)
    filename.sub!(/\.\w+$/, '.png')
    FileUtils.mv(target, filename)
    filename
  rescue StandardError
    raise 'Error rounding corners'
  end
end

optparse = OptionParser.new do |opts|
  opts.banner = "Usage: #{File.basename(__FILE__)} 'APP NAME/SEARCH TERM' SLUG"

  opts.on('-h', '--help', 'Display this screen') do
    puts opts
    exit
  end
end

optparse.parse!

icon = GrabIcon.new(ARGV.join(' ').sub(/\.app$/, ''))
puts icon.icon