chncode book downloader

crop.rb

require 'thread'
require 'logger'
require 'fileutils'

dir_name = ARGV[0] || '707-kindle'
NTHREADS = 4
$logger = Logger.new STDERR

puts "Resizing all images..."

$task_queue = []
entries = Dir.glob("#{dir_name}/**/*")
entries.each_with_index do |f, i|
  next unless f[/^[^_]*.gif$/]
  $task_queue << "#{f}"
end

def work
  threads = []
  task_queue = $task_queue.clone
  mutex = Mutex.new
  1.upto(NTHREADS).each do
    threads << Thread.new do
      file_name = nil
      while
        mutex.synchronize {
          file_name = task_queue.shift
        }
        break if file_name.nil?
        yield file_name
      end
    end
  end
  threads.each {|t| t.join}
end

# work do |file_name|
#  $logger.debug file_name
#   %x( convert #{file_name} -resize 800x #{file_name} )
# end

max_height = 600
backward_line_height = 20
work do |file_name|
  / (\d+)x(\d+) / =~ %x( identify #{file_name} )
  width = Regexp.last_match(1).to_i
  height = Regexp.last_match(2).to_i
  $logger.debug "#{width}, #{height}"
  crop_at = 0
  count = 0

  while true
    FileUtils.mkdir_p "output/#{file_name[/.*\//]}"
    cmd = %( convert #{file_name} -crop "#{width}x#{max_height}+#{0}+#{crop_at}" +repage output/#{file_name}_#{'%02d' % count}.gif )
    $logger.debug cmd
    %x( #{cmd} )
    crop_at = crop_at + max_height - backward_line_height
    break if crop_at > height
    count += 1
  end
end

download.rb

require 'mechanize'
require 'logger'

class Downloader
  def initialize(bookid, pageid)
    @agent = Mechanize.new { |agent|
      agent.user_agent_alias = 'Windows Mozilla'
    }

    @log = Logger.new(STDERR)
    @bookid = bookid
    @pageid = pageid
    Dir.exists?(bookid.to_s) or Dir.mkdir(bookid.to_s)
  end

  def parse_and_download(url)
    body = @agent.get(url).body
    @log.debug "Chapter #{url}"
    chapter = body[/\<title\>\D*(\d+).*\<\/title\>/, 1]
    images = body.scan(/\<img src=\"(.*?)\".*?class="imagecontent">/).flatten
    images.each do |url|
      @log.debug "Downloading #{url}"
      file_name = url[/\d+\.gif/]
      file_path = "#{@bookid}/#{chapter}/#{file_name}"
      Dir.exists? "#{@bookid}/#{chapter}" or Dir.mkdir "#{@bookid}/#{chapter}"
      unless File.exists?(file_path) and File.stat(file_path).size > 10
        @agent.get(url).save_as(file_path)
      end
    end
    body[/next_page = \"(.*)\"/, 1]
  end

  def download_all
    url = "http://www.chncode.com/bs/0/#{@bookid}/#{@pageid}.html"
    while true
      next_page = parse_and_download(url)
      break if next_page.nil? or next_page[/index\.html/]
      url = "http://www.chncode.com/bs/0/#{@bookid}/#{next_page}"
    end
  end
end

bookid = 707
pageid = 1627866

Downloader.new(bookid, pageid).download_all

To make a zip pack for every chapter, enter output/ and hit

ls -1 | xargs -I{} zip -0 -r '{}'.zip '{}'