class IMAPProcessor

# File lib/imap_processor.rb, line 78
def self.add_move
  @@options[:MoveTo] = nil

  @@extra_options << proc do |opts, options|
    opts.on(      "--move=MAILBOX",
            "Mailbox to move message to",
            "Default: #{options[:MoveTo].inspect}",
            "Options file name: :MoveTo") do |mailbox|
      options[:MoveTo] = mailbox
    end
  end
end

# File lib/imap_processor.rb, line 339
def initialize(options)
  @options = options
  @verbose = options[:Verbose]
  @boxes = options[:Boxes]
  Net::IMAP.debug = options[:Debug]
end

# File lib/imap_processor.rb, line 118
  def self.process_args(processor_file, args,
                        required_options = {}) # :yield: OptionParser
    @@opts_file_name = File.basename processor_file, '.rb'
    @@opts_file_name = "imap_#{@@opts_file_name}" unless
      @@opts_file_name =~ /^imap_/
    opts_file = File.expand_path "~/.#{@@opts_file_name}"

    if required_options then
      required_options.each do |option, (default, message)|
        raise ArgumentError,
              "required_options message is missing for #{option}" if
          default.nil? and message.nil?
      end
    end

    defaults = [{}]

    if File.exist? opts_file then
      unless File.stat(opts_file).mode & 077 == 0 then
        $stderr.puts "WARNING! #{opts_file} is group/other readable or writable!"
        $stderr.puts "WARNING! I'm not doing a thing until you fix it!"
        exit 1
      end

      defaults = Array(YAML.load_file(opts_file))
    end

    defaults.map { |default|
      options = default.merge @@options.dup

      options[:SSL]        = true unless options.key? :SSL
      options[:Username] ||= ENV['USER']
      options[:Root]     ||= nil
      options[:Verbose]  ||= false
      options[:Debug]    ||= false

      required_options.each do |k,(v,_)|
        options[k]       ||= v
      end

      op = OptionParser.new do |opts|
        opts.program_name = File.basename $0
        opts.banner = "Usage: #{opts.program_name} [options]\n\n"

        opts.separator ''
        opts.separator 'Connection options:'

        opts.on_tail("-h", "--help", "Show this message") do
          puts opts
          exit
        end

        opts.on("-H", "--host HOST",
                "IMAP server host",
                "Default: #{options[:Host].inspect}",
                "Options file name: :Host") do |host|
          options[:Host] = host
        end

        opts.on("-P", "--port PORT",
                "IMAP server port",
                "Default: The correct port SSL/non-SSL mode",
                "Options file name: :Port") do |port|
          options[:Port] = port
        end

        opts.on("-s", "--[no-]ssl",
                "Use SSL for IMAP connection",
                "Default: #{options[:SSL].inspect}",
                "Options file name: :SSL") do |ssl|
          options[:SSL] = ssl
        end

        opts.on(      "--[no-]debug",
                "Display Net::IMAP debugging info",
                "Default: #{options[:Debug].inspect}",
                "Options file name: :Debug") do |debug|
          options[:Debug] = debug
        end

        opts.separator ''
        opts.separator 'Login options:'

        opts.on("-u", "--username USERNAME",
                "IMAP username",
                "Default: #{options[:Username].inspect}",
                "Options file name: :Username") do |username|
          options[:Username] = username
        end

        opts.on("-p", "--password PASSWORD",
                "IMAP password",
                "Default: Read from ~/.#{@@opts_file_name}",
                "Options file name: :Password") do |password|
          options[:Password] = password
        end

        authenticators = Net::IMAP.authenticators
        auth_types = authenticators.keys.sort.join ', '
        opts.on("-a", "--auth AUTH", auth_types,
                "IMAP authentication type override",
                "Authentication type will be auto-",
                "discovered",
                "Default: #{options[:Auth].inspect}",
                "Options file name: :Auth") do |auth|
          options[:Auth] = auth
        end

        opts.separator ''
        opts.separator "IMAP options:"

        opts.on("-r", "--root ROOT",
                "Root of mailbox hierarchy",
                "Default: #{options[:Root].inspect}",
                "Options file name: :Root") do |root|
          options[:Root] = root
        end

        opts.on("-b", "--boxes BOXES", Array,
                "Comma-separated list of mailbox names",
                "to search",
                "Default: #{options[:Boxes].inspect}",
                "Options file name: :Boxes") do |boxes|
          options[:Boxes] = boxes
        end

        opts.on("-v", "--[no-]verbose",
                "Be verbose",
                "Default: #{options[:Verbose].inspect}",
                "Options file name: :Verbose") do |verbose|
          options[:Verbose] = verbose
        end

        opts.on("-n", "--noop",
                "Perform no destructive operations",
                "Best used with the verbose option",
                "Default: #{options[:Noop].inspect}",
                "Options file name: Noop") do |noop|
          options[:Noop] = noop
        end

        opts.on("-q", "--quiet",
                "Be quiet") do
          options[:Verbose] = false
        end

        if block_given? then
          opts.separator ''
          opts.separator "#{self} options:"

          yield opts, options if block_given?
        end

        @@extra_options.each do |block|
          block.call opts, options
        end

        opts.separator ''

        opts.banner << <<-EOF

Options may also be set in the options file ~/.#{@@opts_file_name}

Example ~/.#{@@opts_file_name}:
\tHost=mail.example.com
\tPassword=my password

        EOF

      end # OptionParser.new do

      op.parse! args.dup

      options[:Port] ||= options[:SSL] ? 993 : 143

      # HACK: removed :Boxes -- push down
      required_keys = [:Host, :Password] + required_options.keys
      if required_keys.any? { |k| options[k].nil? } then
        $stderr.puts op
        $stderr.puts
        $stderr.puts "Host name not set" if options[:Host].nil?
        $stderr.puts "Password not set"  if options[:Password].nil?
        $stderr.puts "Boxes not set"     if options[:Boxes].nil?
        required_options.each do |option_name, (_, missing_message)|
          $stderr.puts missing_message if options[option_name].nil?
        end
        exit 1
      end

      options
    } # defaults.map
  end

# File lib/imap_processor.rb, line 314
def self.run(args = ARGV, &block)
  client = nil
  multi_options = process_args args

  multi_options.each do |options|
    client = new(options, &block)
    client.run
  end
rescue Interrupt
  exit
rescue SystemExit
  raise
rescue Exception => e
  $stderr.puts "Failed to finish with exception: #{e.class}:#{e.message}"
  $stderr.puts "\t#{e.backtrace.join "\n\t"}"

  exit 1
ensure
  client.imap.logout if client and client.imap
end

# File lib/imap_processor.rb, line 350
def capability imap, res = nil
  return imap.capability unless res

  data = res.data

  if data.code and data.code.name == 'CAPABILITY' then
    case data.code.data
    when Array then
      data.code.data
    when String then
      data.code.data.split ' '
    else
      raise ArgumentError, "unknown type: #{data.code.data.class}"
    end
  else
    imap.capability
  end
end

# File lib/imap_processor.rb, line 377
def connect(host = @options[:Host],
            port = @options[:Port],
            ssl = @options[:SSL],
            username = @options[:Username],
            password = @options[:Password],
            auth = @options[:Auth]) # :yields: Connection
  imap = Net::IMAP.new host, port, ssl, nil, false
  log "Connected to imap://#{host}:#{port}/"

  capabilities = capability imap, imap.greeting

  log "Capabilities: #{capabilities.join ', '}"

  auth_caps = capabilities.select { |c| c =~ /^AUTH/ }

  if auth.nil? then
    raise "Couldn't find a supported auth type" if auth_caps.empty?
    auth = auth_caps.first.sub(/AUTH=/, '')
  end

  # Net::IMAP supports using AUTHENTICATE with LOGIN, PLAIN, and
  # CRAM-MD5... if the server reports a different AUTH method, then we
  # should fall back to using LOGIN
  if %w( LOGIN PLAIN CRAM-MD5 XOAUTH2 ).include?( auth.upcase )
    auth = auth.upcase
    log "Trying #{auth} authentication"
    res = imap.authenticate auth, username, password
    log "Logged in as #{username} using AUTHENTICATE"
  else
    log "Trying to authenticate via LOGIN"
    res = imap.login username, password
    log "Logged in as #{username} using LOGIN"
  end

  # CAPABILITY may have changed
  capabilities = capability imap, res

  connection = Connection.new imap, capabilities

  if block_given? then
    begin
      yield connection
    ensure
      connection.imap.logout
    end
  else
    return connection
  end
end

# File lib/imap_processor.rb, line 431
def create_mailbox name
  log "LIST #{name}"
  list = imap.list '', name
  return if list
  log "CREATE #{name}"
  imap.create name unless noop?
end

# File lib/imap_processor.rb, line 442
def delete_messages uids, expunge = true
  log "DELETING [...#{uids.size} uids]"
  imap.store uids, '+FLAGS.SILENT', [:Deleted] unless noop?
  if expunge then
    log "EXPUNGE"
    imap.expunge unless noop?
  end
end

# File lib/imap_processor.rb, line 463
def each_message(uids, type) # :yields: TMail::Mail
  parts = mime_parts uids, type

  uids = []

  each_part parts, true do |uid, message|
    mail = TMail::Mail.parse message

    begin
      success = yield uid, mail

      uids << uid if success
    rescue => e
      log e.message
      puts "\t#{e.backtrace.join "\n\t"}" unless $DEBUG # backtrace at bottom
      log "Subject: #{mail.subject}"
      log "Message-Id: #{mail.message_id}"
      p mail.body if verbose?

      raise if $DEBUG
    end
  end

  uids
end

# File lib/imap_processor.rb, line 493
def each_part(parts, header = false) # :yields: uid, message
  parts.each do |uid, section|
    sequence = ["BODY[#{section}]"]
    sequence.unshift "BODY[#{section}.MIME]" unless section == 'TEXT'
    sequence.unshift 'BODY[HEADER]' if header

    body = imap.fetch(uid, sequence).first

    sequence = sequence.map { |item| body.attr[item] }

    unless section == 'TEXT' and header then
      sequence[0].sub!(/\r\n\z/, '')
    end

    yield uid, sequence.join
  end
end

# File lib/imap_processor.rb, line 514
def log(message)
  return unless @verbose
  $stderr.puts "# #{message}"
end

# File lib/imap_processor.rb, line 528
def mime_parts(uids, mime_type)
  media_type, subtype = mime_type.upcase.split('/', 2)

  structures = imap.fetch uids, 'BODYSTRUCTURE'

  structures.zip(uids).map do |body, uid|
    section = nil
    structure = body.attr['BODYSTRUCTURE']

    case structure
    when Net::IMAP::BodyTypeMultipart then
      parts = structure.parts

      section = parts.each_with_index do |part, index|
        break index if part.media_type == media_type and
                       part.subtype == subtype
      end

      next unless Integer === section
    when Net::IMAP::BodyTypeText, Net::IMAP::BodyTypeBasic then
      section = 'TEXT' if structure.media_type == media_type and
                          structure.subtype == subtype
    end

    [uid, section]
  end.compact
end

# File lib/imap_processor.rb, line 560
def move_messages uids, destination, expunge = true
  return if uids.empty?
  verb = expunge ? "MOVE" : "COPY"
  log "%s %d uids to %s:" % [verb, uids.size, destination]

  begin
    imap.copy uids, destination unless noop?
  rescue Net::IMAP::NoResponseError
    unless noop? then
      create_mailbox destination
      imap.copy uids, destination
    end
  end

  delete_messages uids, expunge
end

# File lib/imap_processor.rb, line 604
def noop?
  options[:Noop]
end

# File lib/imap_processor.rb, line 580
def show_messages(uids)
  return if uids.nil? or (Array === uids and uids.empty?)

  fetch_data = 'BODY.PEEK[HEADER.FIELDS (DATE FROM TO SUBJECT)]'
  messages = imap.fetch uids, fetch_data
  fetch_data.sub! '.PEEK', '' # stripped by server

  messages ||= []

  messages.each do |res|
    puts res.attr[fetch_data].delete("\r").gsub(/^/, "  ")
  end
end

# File lib/imap_processor.rb, line 597
def verbose?
  @verbose
end