ebook_extract

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

# Script inputs a Fulcrum monograph metadata CSV file and a
# list of ebooks and validates the title text found
# within the ebook with the title in the metadata.

require 'optparse'
require 'ostruct'
require 'os'

# Determine the root directory of the code base.
script_dir = File.expand_path(File.dirname(__FILE__))
root_dir = File.dirname(script_dir)

require_relative File.join(root_dir, "lib", "logger")

script_logger = UMPTG::Logger.create(logger_fp: STDOUT)

# Process the script parameters.
options = OpenStruct.new
options.extract_cover = false
options.page_num_list = []
option_parser = OptionParser.new do |opts|
  opts.banner = "Usage: #{File.basename(__FILE__)} [-c] [-p <page_num>] <ebook_file> [<ebook_file>..]"
  opts.on('-c', '--cover', 'Extract cover') do |c|
    options.extract_cover = true
  end
  opts.on('-p', '--page <page_num>', 'Extract page number') do |page_num|
    options.page_num_list << page_num
  end
  opts.on_tail('-h', '--help', 'Print this help message') do
    script_logger.info(opts)
    exit 0
  end
end
option_parser.parse!(ARGV)
if ARGV.count < 1
  script_logger.info(option_parser.help)
  exit 0
end
ebook_file_list = ARGV

unless options.extract_cover or options.page_num_list.count > 0
  script_logger.info("no pages specified to extract")
  exit(0)
end

require 'fileutils'
require 'csv'
require 'origami'

require_relative File.join(root_dir, 'lib', 'epub')

ebook_file_list.each do |ebook_file|
  ebook_file = File.expand_path(ebook_file)
  unless File.file?(ebook_file)
    script_logger.error("file \"#{File.basename(ebook_file)}\" does not exist.")
    next
  end
  script_logger.info("processing file \"#{File.basename(ebook_file)}\"")

  case File.extname(ebook_file)
  when '.epub'
    epub = UMPTG::EPUB::Archive.new(epub_file: ebook_file)
    if options.extract_cover
      if epub.cover.nil?
        script_logger.warn("no cover found.")
      else
        cover_file = File.join(File.dirname(ebook_file), File.basename(ebook_file, ".*") + File.extname(epub.cover.name))
        FileUtils.remove(cover_file) if File.exist?(cover_file)
        epub.cover.extract(cover_file)
        script_logger.info("wrote cover #{cover_file}")
      end
    end
    unless options.page_num_list.empty?
      script_logger.info("EPUB page extraction not implemented.")
    end
  when '.pdf'
    pdf = Origami::PDF.read(ebook_file, lazy: true)
  else
    script_logger.error("unknown ebook type #{}. Skipping.")
    next
  end
  STDOUT.flush
end