require "shellwords"
require "readline"

module CoralBackup
  class FileSelector
    attr_reader :files

    def initialize
      @files = []
    end

    def add_file(filename)
      if FileTest.exist?(filename)
        expanded_filename = File.expand_path(filename)
        @files << File.expand_path(expanded_filename)
        warn expanded_filename
      else
        raise Errno::ENOENT, filename
      end
    end

    def self.select
      file_selector = new
      Readline.completion_proc = Readline::FILENAME_COMPLETION_PROC
      while buf = Readline.readline("> ")
        expanded = Shellwords.split(buf)
        warn "WARNING: #{expanded.length} files are being added:" unless expanded.length == 1

        expanded.each do |ex|
          begin
            file_selector.add_file(ex)
          rescue Errno::ENOENT => e
            warn e
          end
        end
      end

      file_selector.files.uniq
    end


    def self.single_select
      file_selector = new
      Readline.completion_proc = Readline::FILENAME_COMPLETION_PROC
      file_added = false
      while !file_added && buf = Readline.readline("> ")
        expanded = Shellwords.split(buf)
        warn "WARNING: #{expanded.length} files are being added:" unless expanded.length == 1
        expanded.each do |ex|
          begin
            file_selector.add_file(ex)
          rescue Errno::ENOENT => e
            warn e
          else
            file_added = true
          end
        end
      end

      raise "Wrong number of files (#{file_selector.files.length} for 1)" unless file_selector.files.length == 1

      file_selector.files[0]
    end
  end
end