#!/usr/bin/ruby -wKU
#
# mailshears, to prune unused mail directories.
#
# Mail users for virtual hosts are stored in SQL, and managed by
# Postfixadmin. However, the physical directories are handled by
# Postfix/Dovecot and are left untouched by Postfixadmin. This is good
# for security, but comes at a cost: Postfixadmin can't remove a
# user's mail directory when his or her account is deleted.
#
# This program compares the list of filesystem users with the ones
# in the database. It outputs any users that exist in the
# filesystem, but not the database.
#

# Define a usage string using the program name.
exe = File.basename($PROGRAM_NAME)
usage = "#{exe} [prune | rm <target> | mv <src> <dst>]"

# Defaults
mode_name = 'prune'
mode = :prune

# Now, if a mode was supplied, it should be in ARGV[0].
if ARGV.length() > 0
  mode_names = ['prune', 'rm', 'mv']
  if mode_names.include?(ARGV.first().downcase()) then
    # Peel the mode name off the head of the list.
    mode_name = ARGV.shift()
  end
end

if mode_name == 'rm' then
  mode = :rm
elsif mode_name == 'mv' then
  mode = :mv
end

# Need this before referencing ExitCodes.
require 'mailshears'

# Since we removed both the executable name and the mode name (if it
# existed) from ARGV, what remains should be the required
# arguments.
if (mode == :prune and (ARGV.length() != 0)) or
    (mode == :rm and (ARGV.length() < 1))   or
    (mode == :mv and (ARGV.length() != 2))   then
  puts "ERROR: missing (or extra) command-line arguments."
  puts "Usage: #{usage}"
  Kernel.exit(ExitCodes::BAD_COMMAND_LINE)
end

cfg = Configuration.new()

# Load each of the plugins that we'll need.
cfg.plugins.each do |plugin_file|
  require "#{mode_name}/plugins/#{plugin_file}"
end

# And the runners.
require "#{mode_name}/#{mode_name}_runner"
require "#{mode_name}/#{mode_name}_dummy_runner"

def make_header(plugin_name)
  # The header that we output before the list of domains/users.
  # Just the path of this script, the current time, and the plugin name.
  exe = File.basename($PROGRAM_NAME)
  header = "#{exe}, "

  current_time = Time.now()
  if current_time.respond_to?(:iso8601)
    # Somehow this method is missing on some machines.
    header += current_time.iso8601.to_s
  else
    # Fall back to whatever this looks like.
    header += current_time.to_s
  end

  header += ' (Plugin: ' + plugin_name + ")\n"
  header += '-' * header.size # Underline the header.

  return header
end


plugin_module = nil

if mode == :rm then
  plugin_module = RmPlugin
elsif mode == :mv then
  plugin_module = MvPlugin
else
  # Safe, catch-all default
  plugin_module = PrunePlugin
end


# Buffer the output so that we can avoid printing the informational
# header when no plugins produce output.
require 'stringio'
output_buffer = StringIO.new()
$stdout = output_buffer

plugin_module.run(cfg, *ARGV)

# Restore stdout, and print the header plus whatever the plugins
# produced if they produced anything. If they didn't, we avoid
# printing the header.
$stdout = STDOUT
if output_buffer.size > 0 then
  puts make_header(plugin_module.to_s())
  puts output_buffer.string()
end