module Rbnotes::Commands

  ##
  # Imports a existing file which specified by the argument as a note.
  #
  # A timestamp is generated referring to the birthtime of the given
  # file.  If birthtime is not available on the system, uses mtime
  # (modification time).
  #
  # When the option, "-m" (or "--use-mtime") is specified, uses mtime
  # instead of birthtime.
  #
  # Occasionally, there is another note which has the same timestmap
  # in the repository.  Then, tries to create a new timestamp with a
  # suffix.  Unluckily, when such timestamp with a suffix already
  # exists, tries to create a new one with increasing suffix.  Suffix
  # will be "001", "002", ..., or "999".  In worst case, all suffix
  # might have been already used.  Then, abandons to import.

  class Import < Command

    def description             # :nodoc:
      "Import a file as a note"
    end

    ##
    # :call-seq:
    #     execute([PATHNAME], Rbnotes::Conf or Hash) -> nil

    def execute(args, conf)
      @opts = {}
      while args.size > 0
        arg = args.shift
        case arg
        when "-m", "--use-mtime"
          @opts[:use_mtime] = true
        else
          args.unshift(arg)
          break
        end
      end

      file = args.shift
      unless file.nil?
        st = File::Stat.new(file)
        time = nil
        if @opts[:use_mtime]
          time = st.mtime
        else
          time = st.respond_to?(:birthtime) ? st.birthtime : st.mtime
        end

        stamp = Textrepo::Timestamp.new(time)
        puts "Import [%s] (timestamp [%s]) ..." % [file, stamp]

        repo = Textrepo.init(conf)
        content = nil
        File.open(file, "r") {|f| content = f.readlines(chomp: true)}

        count = 0
        while count <= 999
          begin
            repo.create(stamp, content)
            break               # success to create a note
          rescue Textrepo::DuplicateTimestampError => _
            puts "A text with the timestamp [%s] has been already exists" \
                 " in the repository." % stamp

            repo_text = repo.read(stamp)
            if content == repo_text
              # if the content is the same to the target file,
              # the specified file has been already imported.
              # Then, there is nothing to do.  Just exit.
              puts "The note [%s] in the repository exactly matches" \
                   " the specified file." % stamp
              puts "It seems there is no need to import the file [%s]." % file
              break
            else
              puts "The text in the repository does not match the" \
                   " specified file."
              count += 1
              stamp = Textrepo::Timestamp.new(stamp.time, count)
              puts "Try to create a note again with a new " \
                   "timestamp [%s]." % stamp
            end
          rescue Textrepo::EmptyTextError => _
            puts "... aborted."
            puts "The specified file is empty."
            break
          end
        end
        if count > 999
          puts "Cannot create a text into the repository with the" \
               " specified file [%s]."  % file
          puts "For, the birthtime [%s] is identical to some notes" \
               " already exists in the reopsitory." % time
          puts "Change the birthtime of the target file, then retry."
        else
          puts "... Done."
        end
      else
        puts "not supecified FILE"
        super
      end
    end

    def help                    # :nodoc:
      puts <<HELP
usage:
    #{Rbnotes::NAME} import [-m|--use-mtime] FILE

Imports a existing file which specified by the argument as a note.

A timestamp is generated referring to the birthtime of the given file.
If birthtime is not available on the system, use mtime (modification
time).
HELP
    end
  end
end