muse-dl/src/pdftk.cr

70 lines
2.0 KiB
Crystal

require "process"
require "file"
require "./fetch"
require "./errors/*"
module Muse::Dl
class Pdftk
PDFTK_BINARY_NAME = "pdftk"
@binary = "/usr/sbin/pdftk"
@tmp_file_path : String
getter :binary
def initialize(tmp_file_path : String)
@tmp_file_path = tmp_file_path
possible_binary = Process.find_executable(Pdftk::PDFTK_BINARY_NAME)
if possible_binary
@binary = possible_binary
else
puts "Could not find pdftk binary, exiting"
Process.exit(1)
end
end
def execute(args : Array(String))
Process.run(@binary, args)
end
def strip_first_page(input_file : String)
output_pdf = File.tempfile("muse-dl-temp", ".pdf")
execute [input_file, "cat", "2-end", "output", output_pdf.path]
File.rename output_pdf.path, input_file
end
def add_bookmark(input_file : String, title : String)
output_pdf = File.tempfile("muse-dl-temp", ".pdf")
bookmark_text_file = File.tempfile("muse-dl-chapter-tmp", ".txt")
bookmark_text = <<-END
BookmarkBegin
BookmarkTitle: #{title}
BookmarkLevel: 1
BookmarkPageNumber: 1
END
File.write(bookmark_text_file.path, bookmark_text)
execute [input_file, "update_info", bookmark_text_file.path, "output", output_pdf.path]
# Cleanup
bookmark_text_file.delete
File.rename output_pdf.path, input_file
end
def stitch(output_file : String, chapter_ids : Array(String))
# Do some sanity checks on each Chapter PDF
chapter_ids.each do |id|
raise Muse::Dl::Errors::MissingChapter.new unless File.exists? Fetch.chapter_file_name(id, @tmp_file_path)
raise Muse::Dl::Errors::CorruptFile.new unless File.size(Fetch.chapter_file_name(id, @tmp_file_path)) > 0
end
# Now let's stitch them together
chapter_files = chapter_ids.map { |id| Fetch.chapter_file_name(id, @tmp_file_path) }
args = chapter_files + ["cat", "output", output_file]
execute args
# TODO: Validate final file here
end
end
end